Phosphine-catalysed, michael addition-curable sulphur-containing polymer compositions

The technical field to which the invention relates.

The present invention relates to phosphine catalyzed compositions containing sulfur-containing prepolymers with terminal groups, which are Michael acceptors, and prepolymers with terminal thiol groups. Phosphine-catalyzed compositions cure at room temperature to produce cured sealants that have properties that are acceptable for use in aerospace sealing materials.

The level of technology

Sealants used in aerospace and other areas should meet the requirements for mechanical, chemical and environmental properties. Sealants can be applied to various surfaces, including metal surfaces, primers, intermediate coatings, finished coatings, and aged coatings. In sealants, such as those described in US N 6,172,179, an amine catalyst is used to produce a cured product. Such systems, as a rule, are cured within 2-12 hours and, although they possess acceptable resistance to fuel and heat resistance for many applications, improved characteristics of the cured product are in demand.

Michael's addition reactions for curing are often used in acrylic-based polymer systems and, as disclosed in US 3,138,573, have been adapted for use in polysulfide compositions. The use of Michael's addition reaction to cure sulfur-containing polymers not only leads to cured sealants with a higher curing rate and improved performance, including resistance to fuel and heat resistance, but also provides a sealant with improved physical properties, such as relative elongation. The use of the Michael addition reaction for sulfur-containing polymer compositions suitable for sealants in aerospace applications is disclosed in US 13 / 529,237, filed June 21, 2012, which is fully incorporated by reference.

The compositions disclosed in US 13 / 529,237 use one or more basic catalysts, such as amine catalysts. In the presence of a suitable base such as 1,8-diazabicycloundec-7-ene (DBU), the Michael thiol addition reaction is very fast and the curing time is usually less than 2 hours. Without a suitable basic catalyst, the Michael reaction between, for example, a thiol-terminated polythioether and a Michael acceptor is slow, ensuring viability, for example, depending on temperature, from several days to several weeks. Reaction mechanisms for the Michael thiol addition reaction are disclosed by Chan et al., 2010 Macromolecules, 43, 6381-6388.

In practice, the above compositions can be prepared as two-part compositions, in which the thiol-terminated sulfur-containing prepolymer and the Michael acceptor are in the form of separate components, with an amine catalyst in one or both components, and the two parts are mixed shortly before use. . For example, if the catalytic amine is a tertiary amine, the amine catalyst may be in one or both components, and if the catalytic amine is a primary or secondary amine, the amine catalyst may be included only in the component with a thiol-terminated sulfur-containing prepolymer. Alternatively, the base catalyst may be provided as a third component, and a component containing a sulfur-containing thiol-terminated prepolymer, component, containing Michael acceptors, and a component containing a base catalyst, can be mixed immediately before use. However, as soon as the components are mixed, the Michael addition reaction takes place and, depending at least partially on temperature and on the type of amine catalyst, the viability is limited to less than 2 hours. In addition, when the composition begins to cure, it is difficult to control the reaction rate in order to take advantage of the complex chemical processes that occur after applying the sealant to the surface. on temperature and on the type of amine catalyst, pot life is limited to less than 2 hours. In addition, when the composition begins to cure, it is difficult to control the reaction rate in order to take advantage of the complex chemical processes that occur after applying the sealant to the surface. on temperature and on the type of amine catalyst, pot life is limited to less than 2 hours. In addition, when the composition begins to cure, it is difficult to control the reaction rate in order to take advantage of the complex chemical processes that occur after applying the sealant to the surface.

Michael addition reactions for curing, catalyzed by appropriate bases, such as primary or secondary amines, are used in aerospace sealants. For example, Michael’s acceptor end-prepolymers suitable for sealants in aerospace applications are disclosed in the US application entitled “Fuel-resistant urethane-containing prepolymers with Michael end-groups, and their compositions Keledjian, Ito and Lin filed together with This application, US 13/923941, filed June 21, 2013 and US 14/065499, filed October 29, 2013, each of which is fully incorporated by reference. Sulfur-containing prepolymers with terminal Michael acceptors,

Tertiary phosphines are known to catalyze Michael addition reactions. Michael addition reactions for curing coating compositions using tertiary phosphines as catalysts are described, for example, in US 2010/0068393. Phosphines as a catalyst provide fast cure for a few seconds, even at room temperature, and therefore can be useful for spray coatings.

Summary of Invention

Phosphine-catalyzed compositions are disclosed that contain sulfur-containing polymers with Michael-acceptor end groups, which provide cured sealants with properties that are acceptable for use of sealants in aerospace applications.

In accordance with the first aspect, compositions are disclosed that include a sulfur-containing prepolymer with terminal groups that are Michael acceptors, a sulfur-containing prepolymer with terminal thiol groups; and phosphine catalyst.

In the second aspect, disclosed are methods for using a composition comprising a sulfur-containing prepolymer with terminal groups that are Michael acceptors, a sulfur-containing prepolymer with terminal thiol groups; and a phosphine catalyst, comprising applying the composition to a substrate; and curing the composition to obtain a cured sealant.

Brief description of the drawing

FIG. 1 is a graph showing the hardness (Shore A) of a composition comprising a polythioether with a terminal group of di (vinylsulfonyl) alkanol, a combination of polythioethers with terminal thiol groups and 0.04% of the mass. trioctylphosphine during curing at room temperature.

We now turn to some embodiments of the compositions and methods. The disclosed embodiments are not intended to limit the scope of the claims. On the contrary, the claims are intended to cover all alternatives, modifications and equivalents.

The implementation of the invention

For the purposes of the following description, it should be understood that the embodiments proposed by the present invention may suggest various alternative embodiments and sequence of steps, unless otherwise indicated. In addition, with the exception of examples, or unless otherwise indicated, all numbers expressing, for example, the quantities of ingredients used in the description and the claims, should be understood as being preceded in all cases by the term "about." Accordingly, unless otherwise indicated, the numerical parameters presented in the following description and appended claims are approximate and may vary depending on the properties desired. At least, but not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims,

Although the numerical ranges and parameters defining the broad scope of the invention are approximate, the numerical values ​​indicated in the specific examples are presented as accurately as possible. However, any numerical value essentially contains certain errors that inevitably arise from the standard deviation found in their respective measurements.

In addition, it should be understood that any numerical range given in the description implies the inclusion of all subranges covered by it. For example, the range "1-10" is intended to include all subranges between (and including) the specified minimum value of about 1 and the specified maximum value of about 10, that is, having a minimum value equal to or more than about 1 and a maximum value equal to or less about 10. Also in this application the use of "or" means "and / or", unless specifically indicated otherwise, although "and / or" may be explicitly used in some cases.

A dash ("-") that is not between two letters or characters is used to indicate the covalent bond point of a substituent or between two atoms. For example, the chemical group -CONH₂ covalently bonded to another chemical moiety through a carbon atom. In some cases, the expression "- *" is used to designate a connection point.

"Alcanarene" refers to a hydrocarbon group having one or more aryl and / or arenediyl groups and one or more alkyl and / or alkanediyl groups, where aryl, arenediyl, alkyl and alkanediyl are defined in the description. In some embodiments, each aryl and / or arenediyl group (s) is C_6-12, WITH_6-10 and in some embodiments, phenyl or benzenediyl. In some embodiments, each alkyl and / or alkanediyl group (s) is C_1-6, WITH_1-4, WITH_1-3 and in some embodiments methyl, methanediyl, ethyl or ethane-1,2-diyl. In some embodiments, the alkanarene group is C_4-18 alkanarene, C_4-16 alkanarene, C_4-12 alkanarene, C_4-8 alkanarene, C_6-12 alkanarene, C_6-10 alkanarene and in some implementations C_6-9 alkanarene. Examples of alkanarene groups include diphenylmethane.

“Alkanarendiyl” refers to the biradical of the alkanarene group. In some embodiments, the alkane quenyl group is C_4-18 alkanarendiyl, C_4-16 alkanarendiyl, C_4-12 alkanarendiyl, C_4-8 alkanarendiyl, C_6-12 alkanarendiyl, C_6-10 alkanarendiyl and in some implementations With_6-9 alkanarendiyl. Examples of alkane-diene groups include diphenylmethane-4,4'-diyl.

“Alcandiyl” refers to a biradical of a saturated, branched or unbranched, acyclic hydrocarbon group having, for example, 1-18 carbon atoms (C_1-18), 1-14 carbon atoms (C_1-14), 1-6 carbon atoms (C_1-6), 1-4 carbon atoms (C_1-4) or 1-3 carbon atoms (С_1-3). It should be borne in mind that branched alkanediyl has at least three carbon atoms. In some embodiments, alkanediyl is C_2-14 alkanediyl, C_2-10 alkanediyl, C_2-8 alkanediyl, C_2-6 alkanediyl, C_2-4 alkanediyl and in some implementations C_2-3 alkanediyl. Examples of alkanediyl groups include methanediyl (—CH₂-), ethane-1,2-diyl (-CH₂CH₂-), propane-1,3-diyl and iso-propane-1,2-diyl (for example, -CH₂CH₂CH₂- and-CH (CH₃) CH₂-), butane-1,4-diyl (-CH₂CH₂CH₂CH₂-), pentane-1,5-diyl (-CH₂CH₂CH₂CH₂CH₂-), hexane-1,6-diyl (-CH₂CH₂CH₂CH₂CH₂CH₂-), heptane-1,7-diyl, octane-1,8-diyl, nonan-1,9-diyl, decane-1,10-diyl, dodecane-1.12-diyl, etc.

“Alkancycloalkane” refers to a saturated hydrocarbon group having one or more cycloalkyl and / or cycloalkanediyl groups and one or more alkyl and / or alkanediyl groups, where cycloalkyl, cycloalkanediyl, alkyl and alkanediyl are defined in the description. In some embodiments, each cycloalkyl and / or cycloalkanediyl group (s) is C_3-6, WITH_5-6 and in some embodiments, cyclohexyl or cyclohexanediyl. In some embodiments, each alkyl and / or alkanediyl group (s) is C_1-6, WITH_1-4, WITH_1-3 and in some embodiments methyl, methanediyl, ethyl or ethane-1,2-diyl. In some implementations, the alkalcycloalkane group is C_4-18 alkancycloalkane, C_4-16 alkancycloalkane, C_4-12 alkancycloalkane, C_4-8 alkancycloalkane, C_6-12 alkancycloalkane, C_6-10 alkanecycloalkane and in some implementations With_6-9 alkancycloalkane. Examples of alkane cycloalkane groups include 1,1,3,3-tetramethylcyclohexane and cyclohexylmethane.

“Alkancycloalkanediyl” refers to the biradical of the alkancycloalkane group. In some embodiments, the alkancycloalkanediyl group is C_4-18 alkancycloalkanediyl, C_4-16 alkancycloalkanediyl, C_4-12 alkancycloalkanediyl, C_4-8 alkancycloalkanediyl, C_6-12 alkancycloalkanediyl, C_6-10 alkancycloalkanediyl and in some implementations C_6-9 alkancycloalkanediyl. Examples of alkane cycloalkanyl groups include 1,1,3,3-tetramethylcyclohexane-1,5-diyl and cyclohexylmethane-4,4'-diyl.

"Alkenyl" refers to a group having the structure -CR = CR₂where the alkenyl group is a terminal group and is linked to a larger molecule. In such implementations, each R can be selected, for example, from hydrogen and C_1-3-alkyl In some embodiments, each R is hydrogen and an alkenyl group has the structure —CH = CH₂.

“Alkoxy” refers to the group —OR, where R is alkyl as defined herein. Examples of alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy, and n-butoxy. In some embodiments, the alkoxy group is C_1-8 alkoxy, C_1-6 alkoxy, C_1-4 alkoxy and in some implementations C_1-3 alkoxy.

"Alkyl" refers to a mono radical of a saturated, branched or unbranched acyclic hydrocarbon group, including, for example, 1-20 carbon atoms, 1-10 carbon atoms, 1-6 carbon atoms, 1-4 carbon atoms, or 1-3 carbon atoms. It should be borne in mind that branched alkyl has at least three carbon atoms. In some implementations, the alkyl group is C_1-6 alkyl, C_1-4 alkyl and in some implementations C_1-3 alkyl. Examples of alkyl groups include methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-hexyl, n-decyl, tetradecyl, and the like. In some implementations, the alkyl group is_1-6 alkyl, C_1-4 alkyl and in some implementations C_1-3 alkyl. It should be borne in mind that branched alkyl has at least three carbon atoms.

“Aryl” refers to a monovalent aromatic hydrocarbon radical obtained by removing one hydrogen atom from one carbon atom of the original aromatic ring system. Aryl includes 5- and 6-membered carbocyclic aromatic rings, for example benzene; bicyclic ring systems in which at least one ring is carbocyclic and aromatic, for example naphthalene, indane and tetralin; and tricyclic ring systems in which at least one ring is carbocyclic and aromatic, for example, fluorene. Aryl includes polycyclic systems with at least one carbocyclic aromatic ring, condensed with at least one carbocyclic aromatic ring, cycloalkyl ring or heterocycloalkyl ring. For example, aryl includes 5- and 6-membered carbocyclic aromatic rings fused to a 5- or 7-membered heterocycloalkyl ring containing one or more heteroatoms selected from N, O, and S. For such condensed bicyclic systems in which only one of the cycles represents is a carbocyclic aromatic ring, the point of attachment may be in the carbocyclic aromatic ring or heterocycloalkyl ring. Examples of aryl groups include those derived from acenaphthylene, acephenanthrilene, anthracene, azulene, benzene, chrysene, coronene, fluoranthene, fluorene, hexacene, hexafene, hexaline, asyme indacene, simm indacene, indan, indene, naphthalene, octazene, octane, heximene, heximene, asymme indidecene, symm indacene, indane, indene, indene, naphthalene, octazene, octane, hexafene, hectalene, heximene, fluxylene octalene, ovaline, penta-2,4-diene, pentacene, pentalene, pentafen, perylene, phenalene, phenanthrene, pisena, pleianene, pyrene, pyrantran, rubicin, triphenylene, trinaphthalene, etc. In some embodiments, an aryl group may have from 6 to 20 carbon atoms, and in some embodiments, from 6 to 12 carbon atoms. Aryl, however, does not include or partially coincides with heteroaryl, separately defined in this description. Therefore, a polycyclic system in which one or more carbocyclic aromatic rings are condensed with a heterocycloalkyl aromatic cycle is heteroaryl, rather than aryl, as defined herein. In some embodiments, the aryl group is phenyl. A polycyclic system in which one or more carbocyclic aromatic rings are condensed with a heterocycloalkyl aromatic cycle is heteroaryl, rather than aryl, as defined herein. In some embodiments, the aryl group is phenyl. A polycyclic system in which one or more carbocyclic aromatic rings are condensed with a heterocycloalkyl aromatic cycle is heteroaryl, rather than aryl, as defined herein. In some embodiments, the aryl group is phenyl.

“Arylalkyl” refers to an acyclic alkyl radical in which one of the hydrogen atoms bonded to a carbon atom is replaced by an aryl group. Examples of arylalkyl groups include benzyl, 2-phenylethan-1-yl, 2-phenylethen-1-yl, naphthylmethyl, 2-naphthylethan-1-yl, 2-naphthylene-1-yl, naphtobenzyl, 2-naphtofenyl etn-1-yl and etc. Where specific alkyl moieties are provided, the arylalkanyl, arylalkenyl or arylalkynyl nomenclature is used. In some embodiments, the arylalkyl group is C_7-16 arylalkyl, for example, for example, the alkanyl alkenyl or alkynyl moiety of the arylalkyl group is C_1-6 and the aryl moiety is C_6-10. In some embodiments, the arylalkyl group is C_7-9 arylalkyl, where the alkyl part is a_1-3 alkyl, and the aryl part is phenyl. In some embodiments, the arylalkyl group is C_7-16 arylalkyl, C_7-14 arylalkyl, C_7-12 arylalkyl, C_7-10 arylalkyl, C_7-8 arylalkyl and in some implementations benzyl.

"Cycloalkanediyl" refers to the biradical of a saturated monocyclic or polycyclic hydrocarbon group. In some embodiments, the cycloalkanediyl group is C_3-12 cycloalkanediyl, C_3-8 cycloalkanediyl, C_3-6 cycloalkanediyl and in some implementations C_5-6 cycloalkanediyl. Examples of cycloalkanyl groups include cyclohexane-1,4-diyl, cyclohexane-1,3-diyl and cyclohexane-1,2-diyl.

"Cycloalkyl" refers to a saturated monocyclic or polycyclic hydrocarbon monoradical group. In some embodiments, the cycloalkyl group is C_3-12 cycloalkyl, C_3-8 cycloalkyl, C_3-6 cycloalkyl and in some implementations With_5-6 cycloalkyl.

"Heteroalkanediyl" refers to an alkanediyl group in which one or more of the carbon atoms is replaced by a heteroatom, such as N, O, S, or P. In some embodiments, the heteroalkoalkyldiyl heteroatom is selected from N and O.

"Heteroalkanediene" refers to an alkanediridyl group in which one or more of the carbon atoms is replaced by a heteroatom, such as N, O, S, or P. In some embodiments, the heteroatom of the heteroalkanarendiyl is selected from N and O.

"Heterocycloalkanediyl" refers to a cycloalkanediyl group in which one or more of the carbon atoms is replaced by a heteroatom, such as N, O, S, or P. In some heterocycloalkanediyl embodiments, the heteroatom is selected from N and O.

"Obtained" refers to a functional group or fragment obtained by reaction with another reactive functional group or fragment. For example, a fragment, -CH₂-CH₂-S- can be obtained by the reaction of the alkenyl group -CH = CH₂ with a thiol group —SH. Similarly, the -S- fragment can be obtained by the reaction of -SH with a group that can react with thiol groups. In some embodiments, the group —R′— is obtained by reacting the group —R with a reactive group. In some implementations, the fragment -R 'is obtained by the reaction of compound R with a reactive group.

The core of a sulfur-containing prepolymer or adduct refers to a fragment that forms a sulfur-containing prepolymer or adduct without terminal functional groups. For example, the core of a sulfur-containing prepolymer or adduct having the structure: R^f-RR^fwhere each r^f represents a fragment comprising a terminal functional group, is -R-.

The core of a diisocyanate refers to a fragment that forms a diisocyanate without isocyanate groups. For example, the core of a diisocyanate having the structure O = C = NRN = C = O is represented by -R-.

"Michael acceptor" refers to an activated alkene, such as an alkenyl group adjacent to an electron-acceptor group, such as ketone, halogen, carbonyl (-CO), nitro (-NO₂), nitrile (-CN), alkoxycarbonyl (-COOR), phosphonate (-PO (OR)₂), trifluoromethyl (-CF₃), sulfonyl (-SO₂-), trifluoromethanesulfonyl (-SO₂CF₃), or p-toluensulfonyl (-SO₂-C₆H_four-CH₃). In some embodiments, the Michael acceptor group is selected from vinyl ketone, vinyl sulfone, quinone, enamine, ketimine, oxazolidine, and acrylate. In some embodiments, the Michael acceptor or the Michael acceptor group does not include acrylates. Other examples of Michael acceptors are disclosed in Mather et al., Prog. Polym. Sci. 2006, 31, 487-531, and include acrylate esters, acrylonitrile, acrylamides, maleimides, alkyl methacrylates, cyanoacrylates. Other Michael acceptors include vinyl ketones, α, β-unsaturated aldehydes, vinyl phosphonates, acrylonitrile, vinyl pyridines, some azo compounds, β-keto acetylenes, and acetylene ethers. In some embodiments, the Michael acceptor group is derived from vinyl sulfone and has the structure of formula (1):

<img file="RU2672103C2_D0001.tif" he="7" wi="107" img-format="jpg" img-content="undefined" />

in which R is independently selected from hydrogen, fluorine and C_1-3 alkyl. In some embodiments, R is hydrogen. In some embodiments, the Michael acceptor or Michael acceptor group does not include acrylates. A "Michael acceptor compound" refers to a compound comprising at least one Michael acceptor. In some embodiments, the Michael acceptor compound is divinyl sulfone, and the Michael acceptor group is vinyl sulfonyl (-S (O)₂-CH = CH₂).

A "Michael acceptor compound" refers to a compound comprising at least one Michael acceptor. In some embodiments, the Michael acceptor compound is divinyl sulfone, and the Michael acceptor group is vinyl sulfonyl, for example, (-S (O)₂-CH = CH₂). Other examples of Michael acceptors are disclosed in Mather et al., Prog. Polym. Sci. 2006, 31, 487-531, and include acrylate esters, acrylonitrile, acrylamides, maleimides, alkyl methacrylates, cyanoacrylates. Types of compounds that act as Michael acceptors include cyanides, quinones, nitroalkenes, acrylonitriles, acrylates, methanstats, cyrdenes, quinones, nitroalkenes, acrylonitriles, acrylates, methanstats, cyrdenes, quinones, nitroalkenes, acrylonitriles, acrylates, methanstats, cyrmes, quinones, nitroalkenes, acrylonitriles, acrylates, methanstats, cyrmes, quinones, nitroalkenes, acrylonitriles, acrylates, methanstats, cyrmes, quinones, nitroalkenes, acrylonitriles, acrylates, methacrylates, and cents. , dialkyl vinylsulfonate and vinyl sulfones. Other Michael acceptors include vinyl ketones, α, β-unsaturated aldehydes, vinyl phosphonates, acrylonitrile, vinyl pyridines, some azo compounds, β-keto acetylenes, and acetylene ethers. In some embodiments, the Michael acceptor compound is divinyl sulfone, and the Michael acceptor group is vinyl sulfonyl, i.e. -S (O)₂-CH = CH₂. In some embodiments, the Michael acceptor compound is a bis (vinyl sulfonyl) alkanol, and the Michael acceptor group is 1- (ethylene sulfonyl) -n- (vinyl sulfonyl) alkanol, i.e. -CH₂-CH₂-S (O)₂-R^ten-CH (OH) -R^ten-S (O)₂-CH = CH₂, and in some embodiments, 1- (ethylenesulfonyl) -3- (vinylsulfonyl) propan-2-ol (-CH₂-CH₂-S (O)₂-CH₂-CH (-OH) -CH₂-S (O)₂-CH = CH₂).

Also well known are Michael acceptors, having more than one Michael acceptor group. Examples include diacrylates such as ethylene glycol diacrylate and diethylene glycol diacrylate, dimethacrylates such as ethylene glycol methacrylate and diethylene glycol methacrylate, bismaleimides such as N, N '- (1,3-phenylene) dialimimide and 1,1' - (methylene di-4,1-phenylene) bismaleimide, vinyl sulfones, such as divinyl sulfone and 1,3-bis (vinyl sulfonyl) -2-propanol, etc. In some embodiments, the Michael acceptor group has the structure of formula (1a) or formula (1b):

<img file="RU2672103C2_D0002.tif" he="6" wi="160" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0003.tif" he="6" wi="160" img-format="jpg" img-content="undefined" />

where each r^ten independently selected from C_1-3alkandiyl

A “metal ligand” refers to an ion or molecule that binds to a metal atom and potentially other atoms, to form a coordination complex. The bond between the metal and or atoms usually involves the transfer of one or more electron pairs to the metal and the nature of the bond may be covalent or ionic. The metal ligands of the present invention are capable of forming coordination complexes with aerospace surfaces, such as aluminum and titanium surfaces, which can be oxidized. In the case of oxidized surfaces, the ligand for the metal can form a coordination complex with a metal such as Al (III) and oxygen atoms. The coordination complex can increase the adhesion of a coating or sealant to a metal or oxidized metal surface.

Metal ligands can be incorporated into the prepolymer backbone. Such reactive ligands for the metal may be commercially available or may be obtained, including the appropriate reactive substituent groups, using methods known to those skilled in the art. Examples of sulfur-containing polymers, including ligands for the metal, are disclosed in US 13/923903, filed June 21, 2013, and US 14/065554, filed October 29, 2013, each of which is incorporated by reference in its entirety.

Hydroxypyridinones include groups such as 3-hydroxy-4-pyridinone and 3-hydroxy-2-pyridinone, having the structure of formula (3a) or formula (3b), respectively:

<img file="RU2672103C2_D0004.tif" he="45" wi="39" img-format="jpg" img-content="undefined" /><img file="RU2672103C2_D0005.tif" he="39" wi="40" img-format="jpg" img-content="undefined" />

where R is an organic group, such as an alkyl group. The ligand for the metal is a derivative of hydroxypyridinone, comprising a hydroxypyridinone group and one or more reactive functional groups, such as thiol terminal groups.

"Acetylacetonate group" refers to a group of structure:

<img file="RU2672103C2_D0006.tif" he="19" wi="32" img-format="jpg" img-content="undefined" />

In some embodiments, acetylacetonate refers to a metal chelating agent comprising an acetylacetonate ligand and one or more reactive functional groups. In some embodiments, one or more reactive functional groups may interact with a thiol group, such as an epoxy group, an alkenyl group, a Michael acceptor group, or a group containing a saturated carbon atom with a substitutable group that is well suited for nucleophilic substitution, such as, for example, -Cl, -Br, -I, -OSO₂CH₃ (mesilate), -OSO₂-C₆H_four-CH₃ (tosylate), etc.

"Quinones" refers to compounds having a fully conjugated cyclic structure of a dione, obtained from aromatic compounds by transforming an even number of -CH = groups into -C (= O) - groups with the necessary rearrangement of double bonds. Examples of quinones include 1,2-benzoquinone, 1,4-benzoquinone, 1,4-naphthaloquinone and 9,10-anthraquinone. The quinone group may be a ligand for a metal.

"Maleimide" refers to a compound having a maleimide group:

<img file="RU2672103C2_D0007.tif" he="36" wi="27" img-format="jpg" img-content="undefined" />

Bismaleimide refers to a compound having two maleimide groups, where two maleimide groups are bonded to nitrogen atoms through a linker. Sulfur-containing prepolymers with terminal maleimide groups are described in US 14 / 065,499, filed October 29, 2013, which is incorporated by reference in its entirety.

The terminal bismaleimide fragment refers to a fragment having a terminal maleimide group. In some embodiments, the terminal maleimide group is derived from a bismaleimide, such as a compound having a structure of formula (4a):

<img file="RU2672103C2_D0008.tif" he="34" wi="114" img-format="jpg" img-content="undefined" />

where r¹⁵ is a divalent organic radical, and the end group has the structure of formula (4b):

<img file="RU2672103C2_D0009.tif" he="34" wi="109" img-format="jpg" img-content="undefined" />

and is referred to herein as the 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1 H-pyrrole-2,5-dione group. In some embodiments, the terminal maleimide group is prepared from 1,1 ′ - (methylene di-4,1-phenylene) bismaleimide of formula (5a), also referred to as 1,1 ′ - (methylene bis (4,1-phenylene) bis (1H-pyrrole -2,5-dione) and the terminal group has the structure of formula (5b):

<img file="RU2672103C2_D0010.tif" he="35" wi="124" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0011.tif" he="33" wi="123" img-format="jpg" img-content="undefined" />

In some embodiments, the maleimide group includes a 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrol-2,5-dione group. In some embodiments, all terminal maleimide groups may be the same and in some embodiments, at least some of the terminal maleimide groups are different.

Other examples of compounds having two or more maleimide groups include ethylene bismaleimide; 1,6-bismaleimidohexane; 2,4-dimaleimidotoluene, N, N'-1,3-phenylenedimaleimide; 1,4-bis (maleimido) butane trimethylene bismaleimide; p, p'-dimaleimidophenylmethane; pentamethylene bismaleimide-1H-pyrrole-2,5-dione; 1,1 '- (1,8-octanediyl) bis-1H-pyrrole-2,5-dione, 1,1' - (1,7-heptanediyl) bis-4,4'-dithiobis (phenyl maleimide); methylenebis (N-carbamylmaleimide), 1,9-bis (maleimide) nonane; 1,1'-decane-1,10-diylbis (1H-pyrrole-2,5-dione); O-phenylenediamine dimaleimide, bis (N-maleimidomethyl) ether; 1,5-bis (maleimide) -2-methylpentane; N, N'-1,4-phenylenedimaleimide; 1,1 '- (2-methyl-1,3-phenylene) bis (1H-pyrrole-2,5-dione); Kerimid 601 resin; tetrakis- (N-2-aminoethylmaleimide); 1- (2,5-dimethylphenyl) pyrrole-2,5-dione; SureCN331305, SureCN349749 or 1,1'-diphenyl-4,4 '

"Bis (sulfonyl) alkanol" refers to a compound of the general formula R^eight-S (O)₂-R^ten-CH (-OH) -R^ten-S (O)₂-R^eightwhere each r^eight represents a fragment having a reactive functional group; and every r^ten independently selected from C_1-3 alcandiyl. In some embodiments, each R^eight includes a terminal group that reacts with a thiol group, such as, for example, an alkenyl group, an epoxy group, a group that is a Michael acceptor, or a group that includes a saturated carbon atom with a substitutable group that is well suited for nucleophilic substitution, such as, for example, - Cl, -Br, -I, -OSO₂CH₃ (mesilate), -OSO₂-C₆H_four-SN₃ (tosylate), etc. In some implementations, the bis (sulfonyl) alkanol may be a bis (vinylsulfonyl) alkanol comprising terminal alkenyl groups. In some embodiments, the bis (sulfonyl) alkanol may be a bis (vinylsulfonyl) alkanol, wherein R^eight includes a terminal alkenyl group, such as a compound having the formula CH₂= CH-S (O)₂-R^ten-CH (-OH) -R^ten-S (O)₂-CH = CH₂. In some embodiments, the bis (vinylsulfonyl) alkanol is 1,3-bis- (vinylsulfonyl) -2-propanol. In some embodiments, a compound containing a bis (sulfonyl) alkanol can be obtained by reacting a bis (vinylsulfonyl) alkanol with a compound having a reactive terminal functional group and an end group that reacts with the terminal alkenyl groups of a bis (vinylsulfonyl) alkanol, such as a thiol group or epoxy group. In such embodiments, a bis (sulfonyl) alkanol may have the structure R^eight'-CH₂-CH₂-S (O)₂-R^ten-CH (-OH) -R^ten-S (O)₂-CH₂-CH₂-R^eight'where each r^eight'represents a fragment obtained by the reaction of compounds with terminal alkenyl groups of bis (vinylsulfonyl) alkanol.

As used herein, “polymer” refers to oligomers, homopolymers, and copolymers that may or may not be cured. Unless otherwise indicated, the molecular weight is the number average molecular weight for polymeric materials, denoted by "Mn", determined, for example, by gel permeation chromatography using a polystyrene standard by a method known in the art.

"Prepolymers" refer to polymers before curing. In general, the prepolymers prepared in the present invention are liquid at room temperature. "Adducts" may refer to prepolymers that are functionalized with a reactive end group; however, the prepolymers may also contain a terminal functional group. Thus, the terms prepolymer and adduct are used interchangeably. The term adduct is often used to refer to a prepolymer, which is an intermediate in the sequence of reactions used to make the prepolymer.

"Polythioether" refers to a compound that includes at least two thioether bonds, i.e. "-CR₂-S-CR₂- "groups. In addition to at least two thioether groups, the polythioethers of the present invention may include at least two acetal and / or ketal groups, for example, at least two -O-CR₂—O— groups where each R is independently selected from hydrogen, C_1-6 alkyl, C_7-12 phenylalkyl substituted With_7-12 phenylalkyl, C_6-12 cycloalkylalkyl substituted With_6-12 cycloalkylalkyl, C_3-12 cycloalkyl substituted With_3-12 cycloalkyl, C_6-12 aryl and substituted C_6-12 aryl In some embodiments, such compounds are prepolymers or adducts. Suitable polythioethers are disclosed, for example, in US 6,172,179, which is fully incorporated by reference.

"Substituted" refers to a group in which one or more hydrogen atoms are each independently substituted with the same or different substituent (s). In some embodiments, the substituent is selected from halogen, —S (O)₂OH, -S (O)₂, -SH, -SR, where R is C_1-6 alkyl, -COOH, -NO₂-NR₂where each R is independently selected from hydrogen and C_1-3 alkyl, -CN, C = O, C_1-6 alkyl, -CF₃, -OH, phenyl, С_2-6 heteroalkyl, C_5-6 heteroaryl, C_1-6 alkoxy and -COR, where R is C_1-6 alkyl. In some embodiments, a substituent is selected from —OH, —NH₂and C_1-3 alkyl.

We now turn to some implementations of compositions, including sulfur-containing prepolymers with terminal groups that are Michael acceptors, sulfur-containing thiol-terminal prepolymers and phosphine catalysts, and methods of using such compositions. The disclosed embodiments are not intended to limit the scope of the claims. On the contrary, the claims are intended to cover all alternatives, modifications and equivalents.

The compositions of the present invention include a sulfur-containing prepolymer with terminal Michael acceptor groups, a sulfur-containing thiol-terminated prepolymer, and a phosphine catalyst. In some embodiments, the phosphine catalyst comprises a controlled release phosphine catalyst. A compound having at least two end groups that react with Michael acceptor groups includes a sulfur-containing thiol-terminated prepolymer, such as a thiol-terminated polythioether prepolymer. A compound having at least two Michael acceptor groups includes a sulfur-containing prepolymer with end groups that are Michael acceptors, such as a prepolymer of a polythioether with terminal groups that are Michael acceptors.

Michael addition reactions can be used in various ways to produce curable compositions. For example, curable compositions prepared in accordance with the present invention may include (a) a thiol-terminated sulfur-containing prepolymer and a Michael-containing sulfur prepolymer with end groups; (b) a thiol-terminated sulfur-containing prepolymer, a low molecular weight polythiol, and a Michael-acceptor-terminated sulfur-containing prepolymer; or (c) a thiol-terminated sulfur-containing prepolymer, a sulfur-containing prepolymer with Michael acceptor end groups, and a low molecular weight compound having at least two Michael acceptor groups; and (d) a thiol-terminated sulfur-containing prepolymer,

Sulfur-containing prepolymers with terminal Michael acceptor groups and sulfur-containing thiol-terminated polymers can be obtained from polythioethers, polysulfides, sulfur-containing polyformals, or a combination of these.

In some embodiments, low molecular weight polythiols and low molecular weight Michael acceptors have an average molecular weight of less than about 400 Daltons and in some embodiments, less than about 1000 Daltons.

Suitable thiol-terminated sulfur-containing prepolymers include thiol-terminated polythioethers, thiol-terminated polysulfides, thiol-terminated sulfur-containing polyformals, and combinations thereof.

In some implementations, the thiol-terminated sulfur-containing prepolymer includes thiol-terminated polythioether comprising a backbone with the structure of formula (6):

<img file="RU2672103C2_D0012.tif" he="9" wi="134" img-format="jpg" img-content="undefined" />

in which, every r^one independently selected from C_2-10 n-alkanediol group, C_3-6 branched alkanediyl group, C_6-8 cycloalkanediyl group, C_6-10 alkanecycloalkanyl group, heterocyclic group, group - [(- CHR³-)_R-X-]_q- (CHR³)_r- in which each r³ selected from hydrogen and methyl;

every r² independently selected from C_2-10 n-alkanediol group, C_3-6 branched alkanediyl group, C_6-8 cycloalkanediyl group, C_6-14 alkane cycloalkanyl group, heterocyclic group and - [(- CH₂-)_p-X-]_q- (CH₂)_r- groups;

each X is independently selected from O, S, and -NH-, -N (-CH₃) -;

m is in the range of 0-50;

n is an integer of 1-60;

p is an integer of 2-6;

q is an integer of 1-5; and

r is an integer of 2-10.

[059] In some implementations of the prepolymer of formula (6) R^one represents - [- (CHR³)_s-X-]_q- (CHR³)_r-, where each X is independently selected from -O- and -S-. In some embodiments, where R^one represents - [- (CHR³)_s-X-]_q- (CHR³)_r-, each X is -O- and in some implementations, each X is -S-.

In some implementations of the prepolymer of formula (6), R^one represents - [- (CH₂)_s-X-]_q- (CH₂)_r-, where each X is independently selected from -O- and -S-. In some embodiments, where R^one represents - [- (CH₂)_s-X-]_q- (CH₂)_r-, each X is -O- and in some implementations, each X is -S-.

In some embodiments, R^one in the formula (6) is - [(- CH₂-)_R-X-]_q- (CH₂)_r-, where p is 2, X is O, q is 2, r is 2, R² is ethanediyl, m is 2 and n is 9.

In some implementations of formula (6), each R^one is a derivative of dimercaptodioxaoctane (DMDO) and in some embodiments, each R^one is a derivative of dimercaptodiethyl sulfide (DMDS).

In some embodiments of formula (6), each m is independently an integer of 1-3. In some embodiments, each m is the same and is 1, 2, and in some embodiments 3.

In some embodiments of Formula (6), n is an integer of 1-30, an integer of 1-20, an integer of 1-10, and in some embodiments, an integer of 1-5. In addition, in some implementations, n can be any integer from 1 to 60.

In some embodiments of formula (6), each p is independently selected from 2, 3, 4, 5, and 6. In some embodiments, each p is the same and is 2, 3, 4, 5, or 6.

In some embodiments, the thiol-terminated sulfur-containing prepolymer includes a thiol-terminated polythioether prepolymer. Examples of thiol-terminated polythioether prepolymers are disclosed, for example, in US 6,172,179. In some embodiments, the thiol-functional polyethioether adduct includes Permapol^® P3.1E, supplied by PRC-DeSoto International Inc., Sylmar, CA.

In some embodiments, a thiol-terminated sulfur-containing prepolymer includes a thiol-terminated polythioether prepolymer selected from a thiol-terminated polythioether prepolymer of the formula (7a), a polythioether prepolymer of the thiol-terminus of formula (7b), and their combination

<img file="RU2672103C2_D0013.tif" he="9" wi="136" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0014.tif" he="8" wi="149" img-format="jpg" img-content="undefined" />

in which, R^one independently selected from C_2-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-14 alkancycloalkandiyl, C_5-8 heterocycloalkandiyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r-,

Where

s is an integer of 2-6;

q is an integer of 1-5;

r is an integer of 2-10;

every r³ independently selected from hydrogen and methyl; and

each X is independently selected from -O-, -S-, -NR-, and -N (-CH₃) -;

every r² independently selected from C_1-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-14 alkancycloalkanediyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r-, where s, q, r, R³ and X are as defined for R^one;

m is an integer of 0-50;

n is an integer of 1-60; and

p is an integer of 2-6.

B is the core of a z-valent, polyfunctionalizing agent B (-V)_z, wherein,

z is an integer of 3-6; and

each V is a fragment that includes a terminal group that reacts with a thiol group; and

each -V- is obtained by the reaction of -V with thiol.

In some embodiments, in formula (7a) and formula (7b), R^one represents - [(- CH₂-)_R-X-]_q- (CH₂)_r-, where p is 2, X is O, q is 2, r is 2, R² is ethanediyl, m is 2 and n is 9.

In some implementations in the formula (7a) and formula (7b) R^one selected from C_2-6 alkandiyl and - [- (CHR³)_s-X-]_q- (CHR³)_r.

In some implementations in the formula (7a) and formula (7b) R^one is - [- (CHR³)_s-X-]_q- (CHR³)_r and in some embodiments, X is -O-, and in some embodiments, X is -S-.

In some implementations in the formula (7a) and formula (7b), where R^one - [- (CHR³)_s-X-]_q- (CHR³)_rp is 2, r is 2, q is 1 and X is -S-; in some embodiments, where p is 2, q is 2, r is 2 and X is —O—; and in some embodiments, p is 2, r is 2, q is 1 and X is -O-.

In some implementations of formula (7a and formula (7b), where R^one - [- (CHR³)_s-X-]_q- (CHR³)_reach r³ is hydrogen and in some embodiments, at least one R³ is methyl.

In some implementations of formula (7a) and formula (7b), all R^one the same, and in some implementations, at least one R^one to others.

Various methods can be used to obtain polythioethers with thiol terminal groups of formula (7a) and formula (7b). Examples of suitable polythioethers with thiol terminal groups and methods for their preparation are described in US 6,172,179 from column 2, line 29 to column. 4, line 22; from column 6, line 39 to column 10, line 50; and from column 11, line 65 to column. 12, line 22, the cited portions of which are incorporated by reference. Such polythioethers with thiol terminal groups can be difunctional, that is, linear polymers having two terminal thiol groups, or polyfunctional, that is, branched polymers having three or more terminal thiol groups. Acceptable thiol terminal polythioethers are commercially available, for example, Permapol^® P3.1E, manufactured by PRC-DeSoto International Inc., Sylmar, CA.

A thiol-terminated sulfur-containing prepolymer may include a mixture of various thiol-terminated sulfur-containing prepolymers and a thiol-terminated sulfur-containing prepolymers may have the same or different functionality. In some embodiments, the thiol-terminated sulfur-containing prepolymer has an average functionality of 2-6, 2-4, 2-3, and in some embodiments, 2.05-2.5. For example, a thiol-terminated sulfur-containing prepolymer may be selected from a thiol-terminated difunctional sulfur-containing prepolymer, a trifunctional thiol-terminated sulfur-containing prepolymer, and combinations thereof.

In some embodiments, thiol-terminated polythioether can be obtained by reacting a polythiol and a diene, such as divinyl ether, and appropriate amounts of reagents used to prepare the thiolea-terminated polythioethers selected to produce thiol end groups. Thus, in some cases (n or&gt; n, for example, n + 1) moles of a polythiol, such as dithiol or a mixture of at least two different dithiols and about 0.05-1 mol, for example, 0.1-0 , 8 moles of polyfunctionalizing agent may be brought into contact with (n) moles of a diene, such as divinyl ether, or mixtures of at least two different dienes, such as divinyl ether. In some embodiments, the polyfunctionalizing agent is present in the reaction mixture in an amount

The reaction used to obtain a thiol-terminated polythioether prepolymer can be catalyzed by a free radical catalyst. Suitable free radical catalysts include azo compounds, for example, azobisitrile compounds such as azobis (isobutyronitrile) (AIBN); organic peroxides, such as benzoyl peroxide and tert-butyl peroxide; and inorganic peroxides, such as hydrogen peroxide. The reaction can also be carried out by irradiation with ultraviolet light in the presence or absence of a radical initiator / photosensitizer. Ion catalysis methods can also be used, using inorganic or organic bases, for example, triethylamine.

Suitable thiol-terminated polythioether prepolymers can be prepared by reacting divinyl ether or a mixture of divinyl ethers with an excess of dithiol or mixtures of dithiols. Thus, in some embodiments, thiol-terminated polythioether includes a reaction product of reagents, including:

(a) a dithiol of formula (8):

<img file="RU2672103C2_D0015.tif" he="7" wi="57" img-format="jpg" img-content="undefined" />

wherein,

R^one selected from C_2-6 alkanediyl, С_6-8 cycloalkandiyl, C_6-10 alkancycloalkandiyl, C_5-8 heterocycloalkandiyl and - [- (CHR³)_s-X-]_q- (CHR³)_r-; wherein,

every r³ independently selected from hydrogen and methyl;

each X is independently selected from -O-, -S-, -NH-, -NR-, and -N (-CH₃) -;

s is an integer of 2-6;

q is an integer of 1-5; and

r is an integer of 2-10; and

(b) divinyl ether of formula (9):

<img file="RU2672103C2_D0016.tif" he="8" wi="133" img-format="jpg" img-content="undefined" />

wherein,

every r² independently selected from C_1-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-14 alkancycloalkanediyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r- in which s, q, r, R³ and X is as defined above;

m is an integer of 0-50;

n is an integer of 1-60; and

p is an integer of 2-6.

and in some embodiments, the reagents may include (c) polyfunctional compounds, such as polyfunctional compound B (-V)_zwhere B, -V and z are defined above.

In some embodiments, dithiols suitable for use in preparing thiol-terminated polythioesters include compounds of formula (8), other dithiols disclosed in the description, or combinations of dithiols disclosed in the description. In some implementations, the dithiol has the structure of formula (8):

<img file="RU2672103C2_D0017.tif" he="8" wi="107" img-format="jpg" img-content="undefined" />

wherein,

R^one selected from C_2-6 alkanediyl, С_6-8 cycloalkandiyl, C_6-10 alkancycloalkandiyl, C_5-8 heterocycloalkandiyl and - [- (CHR³)_s-X-]_q- (CHR³)_r-; wherein,

every r³ independently selected from hydrogen and methyl;

each X is independently selected from -O-, -S-, -NH-, -NR-, and -N (-CH₃) -;

s is an integer of 2-6;

q is an integer of 1-5; and

r is an integer of 2-10

In some implementations, the dithiol of formula (8) R^one is - [- (CHR³)_s-X-]_q- (CHR³)_r-.

In some embodiments, a dithiol of formula (8), X is selected from —O— and —S—, and thus - [- (CHR³)_s-X-]_q- (CHR³)_r- in the formula (8) is - [- (CHR³)_s-O-]_q- (CHR³)_r- or - [- (CHR³)_s-S-]_q- (CHR³)_r-. In some embodiments, p and r are equal, for example, when p and r are both equal to two.

In some implementations, the dithiol of formula (8), R^one selected from C_2-6 alkandiyl and - [- (CHR³)_s-X-]_q- (CHR³)_r-.

In some implementations, the dithiol of formula (8), R^one is - [- (CHR³)_s-X-]_q- (CHR³)_r- and in some implementations X is -O-, and in some implementations X is -S-.

In some embodiments, where R^one is - [- (CHR³)_s-X-]_q- (CHR³)_r-, s is 2, r is 2, q is 1, and X is -S-; In some embodiments, where s is 2, q is 2 and r is 2 and X is -O-; and in some embodiments, s is 2, r is 2, q is 1, and X is -O-.

In some embodiments, where R^one means - [- (CHR³)_s-X-]_q- (CHR³)_r- each r³ is hydrogen and in some implementations at least one R³ is methyl.

In some implementations of formula (8), each R^one is a derivative of dimercaptodioxaoctane (DMDO) and in some embodiments of the invention each R^one is a derivative of dimercaptodiethyl sulfide (DMDS).

In some embodiments of Formula (8), each m is independently an integer of 1-3. In some embodiments, each m is the same and is 1, 2, and in some embodiments 3.

In some embodiments of formula (8), n is an integer of 1-30, an integer of 1-20, an integer of 1-10, and in some embodiments, an integer of 1-5. In addition, in some implementations, n can be any integer 1-60.

In some embodiments of formula (8), each p is independently selected from 2, 3, 4, 5, and 6. In some embodiments, each p is the same and is 2, 3, 4, 5, or 6.

Examples of suitable dithiols include, for example, 1,2-ethanedithiol, 1,2-propandithiol, 1,3-propandithiol, 1,3-butanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,3-pentanedithiol, 1 5, pentanal 3-oxapentane and the combination of the above substances. Dithiol may have one or more side groups selected from the lower (for example, C_1-6) an alkyl group, a lower alkoxy group, and a hydroxyl group. Suitable alkyl side groups include, for example, C_1-6 linear alkyl, C_3-6 branched alkyl, cyclopentyl and cyclohexyl.

Other examples of suitable dithiols include dimercaptodiethylsulfide (DMDS) (in formula (8), R^one is - [(- CH₂-)_s-X-]_q- (CH₂)_r-, in which s is 2, r is 2, q is 1 and X is -S-); dimercaptodioxaoctane (DMDO) (in the formula (16) R^one is - [(- CH₂-)_s-X-]_q- (CH₂)_r-, in which s is 2, q is 2, r is 2 and X is -O-); and 1,5-dimercapto-3-oxapentane (in the formula (16) R^one is - [(- CH₂-)_s-X-]_q- (CH₂)_r-, in which s is 2, r is 2, q is 1 and X is -O-). Dithiols can also be used, which include both a heteroatom in the carbon backbone and side alkyl groups such as methyl groups. Such compounds include, for example, methyl-substituted DMDS, such as HS-CH₂CH (CH₃) -S-CH₂CH₂-SH, HS-CH (CH₃) CH₂-S-ch₂CH₂-SH and dimethyl-substituted DMDS, such as HS-CH₂CH (CH₃) -S-CHCH₃CH₂-SH and HS-CH (CH₃) CH₂-S-ch₂CH (CH₃) -SH.

Divinyl ethers suitable for the preparation of polythioesters include, for example, the divinyl ethers of formula (9):

<img file="RU2672103C2_D0018.tif" he="7" wi="91" img-format="jpg" img-content="undefined" />

where r² in formula (9) is selected from C_2-6 n-alkanediol group, C_3-6 branched alkanediyl group, C_6-8 cycloalkanediyl group, C_6-10 alkancycloalkanediyl group and - [(- CH₂-)_s-ABOUT-]_q- (- CH₂-)_r-, in which s is an integer 2-6, q is an integer 1-5, and r is an integer 2-10. In some implementations divinyl ether of the formula (9), R² is C_2-6 n-alkanediol group, C_3-6 branched alkanediyl group, C_6-8 cycloalkanediyl group, C_6-10 alkanecycloalkanyl group and in some implementations - [(- CH₂-)_s-O-]_q- (- CH₂-)_r-.

Suitable divinyl ethers include, for example, compounds having at least one hydroxyalkanediyl group, for example, 1-4 hydroxyalkandiyl group, i.e. compounds in which m in formula (9) is an integer in the range of 1-4. In some embodiments, m in formula (9) is an integer in the range of 2-4. You can also use commercially available mixtures of divinyl ethers, which are characterized by a non-integer average value of the number of hydroxyalkanediyl units per molecule. Thus, m in formula (9) can also take the values ​​of rational numbers in the range of 0-10.0, for example, 1.0-10.0, 1.0-4.0, or 2.0-4.0.

Examples of suitable vinyl esters include divinyl ether, ethylene glycol divinyl ether (EG-DVE) (R² in formula (9) is ethanediyl and m is 1), butanediol divinyl ether (BD-DVE) (R² in formula (9) is butanediyl and m is 1), divinyl ether of hexanediol (HD-DVE) (R² in formula (9) is hexanediyl and m is 1), diethylene glycol divinyl ether (DEG-DVE) (R² in formula (9) is ethanediyl and m is 2) triethylene glycol divinyl ether (R² in formula (9) is ethanediyl and m is 3), tetraethylene glycol divinyl ether (R² in formula (9) is ethanediyl and m is 4), cyclohexanedimethanol divinyl ether, polytetrahydrofuryl divinyl ether; trivinyl ether monomers such as trimethylolpropane trivinyl ether; tetrafunctional ester monomers such as pentaerythritol tetravinyl ether; and combinations of two or more monomers of esters, such as polyvinyl ethers. The polyvinyl ether can have one or more side groups selected from alkyl groups, hydroxyl groups, alkoxy groups, and amino groups.

In some embodiments, divinyl ethers in which R² in formula (9) is C_3-6 branched alkanediyl, can be obtained by the interaction of polyhydroxy compounds with acetylene. Examples of divinyl ethers of this type include compounds in which R² in formula (9), is an alkyl-substituted methanediyl group, such as —CH (CH₃) -, for which R² in formula (9) is ethanediyl and m is 3 or alkyl substituted ethanediyl.

Other suitable divinyl esters include compounds in which R² in formula (9), is polytetrahydrofuryl (poly-THF) or polyoxyalkanediyl, such as those with an average of about 3 monomeric units.

Two or more types of polyvinyl ether monomers of formula (9) may be used. Thus, in some embodiments, two dithiols of formula (8) and one polyvinyl ether monomer of formula (9), one dithiol of formula (8) and two polyvinyl ether monomers of formula (9), two dithiols of formula (8) and two monomers of divinyl ether of formula (9), and more than two compounds of one or both of formulas (8) and (9), can be used to obtain different polythioethers with terminal thiol groups.

In some embodiments, the polyvinyl ether monomer comprises from 20 to less than 50 mole percent of the reagents used to make thiol-terminated polythioether, and in some embodiments, from 30 to less than 50 mole percent.

In some embodiments of the present invention, the relative amounts of dithiols and divinyl esters are selected to produce polythioethers having terminal thiol groups. Thus, a dithiol of formula (8) or a mixture of at least two different dithiols of formula (8) can be reacted with a divinyl ether of formula (9) or a mixture of at least two different divinyl ethers of formula (9) in relative amounts such that the molar ratio of thiol groups to alkenyl groups was more than 1: 1, for example, 1.1-2.0: 1.0.

The reaction between dithiols and divinyl ethers and / or polythiols and polyvinyl ethers can be catalyzed by a free radical catalyst. Suitable free radical catalysts include, for example, azo compounds, for example azobisonitriles, such as azo bis (isobutyronitrile) (AIBN); organic peroxides, such as benzoyl peroxide and tert-butyl peroxide; and inorganic peroxides, such as hydrogen peroxide. The catalyst may be a free radical catalyst, an ionic catalyst, or ultraviolet radiation. In some implementations, the catalyst does not include acidic or basic compounds and does not give acidic or basic compounds during decomposition. Examples of free radical catalysts include azo-type catalyst, such as Vazo^®-57 (Du Pont), Vazo^®-64 (Du Pont), Vazo^®-67 (Du Pont), V-70^® (WAKO Specialty Chemicals) and V-65B^® (WAKO Specialty Chemicals). Examples of other free radical catalysts are alkyl peroxides, such as tert-butyl peroxide. The reaction can also be carried out by irradiation with ultraviolet light or without a cationic photoinitiator fragment.

Thiol-terminated polythioethers can be prepared by combining at least one dithiol of formula (8) and at least one divinyl ether of formula (9), followed by the addition of an appropriate catalyst, and carrying out the reaction at a temperature of 30-120 ° C, for example, 70-90 ° C for 2-24 hours, for example, 2-6 hours.

In accordance with this disclosure, thiol-terminated polythioethers may include a polyfunctional polythioether with thiol endgroups, i.e. may have an average functionality of more than 2.0. Suitable polyfunctional thiol-terminated polythioethers include, for example, those that have the structure of formula (10):

<img file="RU2672103C2_D0019.tif" he="7" wi="149" img-format="jpg" img-content="undefined" />

in which z has an average value of more than 2.0 and in some embodiments, a value between 2 and 3, a value of 2-4 and a value of 3-6, and in some embodiments, an integer of 3-6.

Polyfunctionalizing agents suitable for use in the preparation of such polyfunctional thiol-terminated polymers include trifunctionalizing agents, i.e. compounds where z is 3. Suitable trifunctionalizing agents include, for example, triallyl cyanurate (TAC), 1,2,3-propantrythiol, isocyanurate-containing trithiols and their combinations, as disclosed in US 2010/0010133 in paragraphs [0102] - [0105], the cited part of which is incorporated by reference, and isocyanurates, as disclosed, for example, in US 2011/0319559, which is fully incorporated by reference y. Other suitable polyfunctionalizing agents include trimethylolpropane trivinyl ether and polythiols described in US 4,366,307. 4609762; and 5225472, each of which is fully incorporated by reference. Mixtures of polyfunctionalizing agents can also be used. As a result, polythioethers can have a wide range of average functionality. For example, trifunctionalizing agents can provide an average functionality of 2.05-3.0, for example 2.1-2.6. Wider ranges of average functionality can be achieved using tetrafunctional or polyfunctionalizing agents with a higher number of functional groups. Functionality can also be determined using factors such as stoichiometry, as understood by those skilled in the art.

Polysulfides refer to prepolymers that contain one or more sulfide bonds, i.e. -S_x- bonds, where x is 2-4, in the main polymer chain and / or in the lateral positions of the prepolymer chain. In some embodiments, the polysulfide prepolymer will have two or more sulfur-sulfur bonds. Suitable polysulfides are commercially supplied, for example, by Akzo Nobel and Toray Fine Chemicals under the names Thiokpl-LP and Thioplast^®. Thioplast^® products are available in a wide range of molecular weights, for example, from less than 1,100 to more than 8,000, with a molecular weight that is the average molecular weight in grams per mole. In some cases, the polysulfide has a number average molecular weight of 1000-4000 daltons. Examples of suitable polysulfides are disclosed, for example, in US 4,623,711.

Thiol-terminated sulfur-containing polyformal prepolymers used in aerospace sealant applications are disclosed, for example, in US 2012/0234205 and in US 2012/0238707, each of which is fully incorporated by reference.

In some embodiments, a thiol-terminated sulfur-containing prepolymer comprises a thiol-terminated sulfur-containing prepolymer containing a ligand for a metal in which a metal ligand is included in the prepolymer backbone. Sulfur-containing prepolymers containing a ligand for a metal are disclosed in US 14/065554, filed October 29, 2013, US. 13/923903, filed June 21, 2013, and US 13/923941, filed June 21, 2013, each of which is fully incorporated by reference.

Sulfur-containing prepolymers with end groups that are Michael acceptors have at least two terminal unsaturated groups that are activated for Michael addition, such as activated unsaturated groups that serve as Michael acceptors.

Sulfur-containing prepolymers with end groups that are Michael acceptors include at least two terminal groups that are Michael acceptors. In some embodiments, the sulfur-containing prepolymer with Michael acceptor end groups may be difunctional and in some embodiments may have more than 2 functionality, for example, 3, 4, 5, or 6. The sulfur-containing prepolymer with Michael acceptor end groups may include a mixture sulfur-containing prepolymers with end groups that are Michael acceptors with different functionality, characterized by an average functionality of 2.05-6, 2,1-4, 2,1-3, 2,2-2,8 and in some embodiments 2,4- 2.6. Sulfur-containing prepolymer with Michael accepting end groups has at least two end groups, are Michael acceptors, and in some embodiments, has two groups that are Michael acceptors, 3, 4, 5, or 6 groups that are Michael acceptors. A sulfur-containing prepolymer with Michael acceptor end groups may include a combination of adducts having a different number of end groups that are Michael acceptors, characterized, for example, by an average Michael acceptor functionality of 2.05-6, 2,1-4, 2,1- 3, 2.2-2.8 and in some embodiments 2.4-2.6.

Suitable sulfur-containing prepolymers with Michael acceptor end groups include Michael-acceptor polythioethers with Michael end groups, Michael acceptor end-groups with Michael acceptors, Michael-containing sulfur-containing polyforms and end groups, and combinations thereof. For example, any of the polythioethers, polysulfides, and sulfur-containing polyformals suitable for use as thiol-terminated sulfur-containing prepolymers can also be used in the backbone for the sulfur-containing prepolymer with Michael acceptors.

Sulfur-containing prepolymers with Michael accepting end groups suitable for use in aerospace sealant applications are disclosed, for example, in US 13 / 923,941, filed June 21, 2013, US 14/065499 filed October 29, 2013 and US 13/923941, each of which is fully incorporated by reference.

In some embodiments, the sulfur-containing prepolymer with Michael acceptor end groups includes a polythioether with Michael end acceptor groups.

In some embodiments, the sulfur-containing prepolymer with Michael acceptor end groups includes a polythioether with Michael end acceptor groups, including:

(a) a main chain comprising the structure of the formula (6):

<img file="RU2672103C2_D0020.tif" he="7" wi="146" img-format="jpg" img-content="undefined" />

in which (i) each R^one independently selected from C_2-10 n-alkanediol group, C_3-6 branched alkanediyl group, C_6-8 cycloalkanediyl group, C_6-10 alkane cycloalkanyl group, heterocyclic group, - [(- CHR³-)_p-X-]_q(CHR³)_r-groups in which each R³ independently selected from hydrogen and methyl; (ii) each R² independently selected from C_2-10 n-alkanediol group, C_3-6 branched alkanediyl group, C_6-8 cycloalkanediyl group, C_6-14 alkane cycloalkanyl group, heterocyclic group and - [(- CH₂-)_p-X-]_q(CH₂)_r- groups; (iii) each X is independently selected from O, S, and -NR⁶- groups in which R⁶ selected from H and the methyl group; (iv) m is in the range of 0-50; (v) m is an integer of 1-60; (vi) p is an integer of 2-6; (vii) q is an integer of 1-5; and (viii) r is an integer of 2-10; and

(b) at least two end groups that are Michael acceptors.

In some implementations of the compounds of formula (6) R^one is - [(- CHR³-)_p-X-]_q(CHR³)_r-, in which each X is independently selected from -O- and -S-. In some embodiments, where R^one is - [(- CHR³-)_p-X-]_q(CHR³)_r-, each X is -O- and in some implementations, each X is -S-.

In some implementations of the compounds of formula (6) R^one is - [(- CH₂-)_p-X-]_q(CH₂)_r-, where each X is independently selected from -O- and -S-. In some embodiments, where R^one is - [(- CH₂-)_p-X-]_q(CH₂)_r-, each X is -O- and in some implementations, each X is -S-.

In some embodiments, R^one in the formula (6) is - [(- CH₂-)_p-X-]_q(CH₂)_r-, where p is 2, X is O, q is 2, r is 2 R² is ethanediyl, m is 2, and n is 9.

In some implementations, the sulfur-containing prepolymer with Michael accepting end groups includes a polythioether of formula (11a), a polythioether with end groups that are Michael acceptor, formula (11b), or a combination of them:

<img file="RU2672103C2_D0021.tif" he="8" wi="150" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0022.tif" he="8" wi="150" img-format="jpg" img-content="undefined" />

in which:

every r^one independently selected from C_2-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-10 alkancycloalkandiyl, C_5-8 heterocycloalkanediyl - [(- CHR³-)_s-X-]_q- (- CHR³-)_r- where

s is an integer of 2-6;

q is an integer of 1-5;

r is an integer of 2-10;

every r³ independently selected from hydrogen and methyl; and

each X is independently selected from -O-, -S-, -NR-, and -N (-CH₃) -;

every r² independently selected from C_1-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-14 alkancycloalkanediyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r-, where s, q, r, R³ and X are as defined for R^one;

m is an integer of 0-50;

n is an integer of 1-60; and

p is an integer of 2-6.

B is the core of a z-valent, polyfunctionalizing agent B (-V)_z, wherein,

z is an integer of 3-6; and

each V is a group that includes a terminal group that reacts with a thiol group; and

each -V'- is obtained by the reaction of -V with thiol.

every r⁶ independently is a group that includes the end group, which is Michael acceptor.

In some embodiments, in formula (11a) and formula (11b), R^one is - [(- CH₂)_p-X-]_q(CH₂)_r-, where p is 2, X is -O-, q is 2, r is 2, R² is ethanediyl, m is 2, n is 9.

In some implementations of formula (11a) and formula (11b) R^one selected from C_2-6 alkandiyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r-.

In some implementations of formula (11a) and formula (11b), R^one is - [(- CHR³-)_s-X-]_q- (- CHR³-)_r- and in some implementations X is -O-, and in some implementations X is -S-.

In some implementations of formula (11a) and formula (11b), where R^one is - [(- CHR³-)_s-X-]_q- (- CHR³-)_r-, p is 2, r is 2, q is 1 and X is -S-; in some embodiments, where p is 2, q is 2, r is 2 and X is —O—; and in some embodiments, p is 2, r is 2, q is 1 and X is -O-.

In some implementations of formula (11a) and formula (11b), where R^one is - [(- CHR³-)_s-X-]_q- (- CHR³-)_r- each r³ is hydrogen and in some implementations at least one R³ is methyl.

In some embodiments, the adducts of formula (11a) and formula (11b) are all R^one the same and in some implementations at least one R^one is different.

In some embodiments, each -V includes an alkenyl-terminated group.

A sulfur-containing prepolymer with a terminal group that is Michael’s acceptor may be any suitable group that is Michael’s acceptor. In some embodiments, the end Michael acceptor group is derived from bis (vinylsulfonyl) alkanol and in some embodiments derived from bismaleimide.

In some implementations of the prepolymers of formula (11a) and formula (11b), each R⁶ derived from bismaleimide, such as 1,1 '- (methylenebis (4,1-phenylene) bis (1H-pyrrole-2,5-dione) In some embodiments, each R⁶ obtained from ethylene bismaleimide, 1,6-bismaleimidohexane, 2,4-dimaleimidotoluene, N, N'-1,3-phenylenedimaleimide; 1,4-bis (maleimido) butane trimethylene bismaleimide; p, p'-dimaleimidophenylmethane; pentamethylene bismaleimide-1H-pyrrole-2,5-dione; 1,1 '- (1,8-octanediyl) bis-1H-pyrrole-2,5-dione, 1,1' - (1,7-heptanediyl) bis-4,4'-dithiobis (phenyl maleimide); methylenebis (N-carbamylmaleimide), 1,9-bis (maleimide) nonane; 1,1'-decane-1,10-diylbis (1H-pyrrole-2,5-dione); O-phenylendimaleimide, bis (N-maleimidomethyl) ether, 1,5-bis (maleimide) -2-methyl-pentane, N, N'-1,4-phenylenedimaleimide; 1,1 '- (2-methyl-1,3-phenylene) bis (1H-pyrrole-2,5-dione); Kerimid 601 resins; tetrakis (N-2-aminoethylmaleimide); 1- (2,5-dimethylphenyl) pyrrole-2,5-dione; SureCN331305; SureCN349749, or 1,1'-diphenyl-4,4'-diylbis (1H-pyrrole-2,5-dione).

In some embodiments of a sulfur-containing prepolymer with Michael accepting end groups, the prepolymer includes at least two end-maleimide groups.

Michael acceptor groups are well known in the art. In some embodiments, the Michael acceptor group includes an activated alkene, such as an alkenyl group adjacent to an electron acceptor group, such as enone, nitro, halogen, nitrile, carbonyl, or nitro. In some embodiments, the Michael acceptor group is selected from vinyl ketone, vinyl sulfone, quinone. In some embodiments, the Michael acceptor group includes a bis (sulfonyl) alkanol group, for example, the 1- (ethylene sulfonyl) -N- (vinylsulfonyl) alkanol group and in some embodiments the 1- (ethylene sulfonyl) -3- (vinyl sulfonyl) propane group 2-ola. In some implementations, all groups that are Michael acceptors may be the same and in some embodiments, at least

In some embodiments, the sulfur-containing prepolymers with Michael accepting end groups may include at least two end groups of 1- (ethylene sulfonyl) -N- (vinylsulfonyl) alkanol, for example, two terminal groups of 1- (ethylene sulfonyl) -N- ( vinylsulfonyl) alkanol, 3, 4, 5 or 6 terminal groups of 1- (ethylene sulfonyl) -N- (vinylsulfonyl) alkanol. A sulfur-containing prepolymer with Michael accepting end groups may include a combination of adducts having a different number of terminal 1- (ethylene sulfonyl) -N- (vinyl sulfonyl) alkanol groups, characterized, for example, by an average functionality of 1- (ethylene sulfonyl) -N- (vinyl sulfonyl) ) alkanol 2.05-6, 2.1-4, 2.1-3, 2.2-2.8 and in some embodiments 2.4-2.6.

In some embodiments, the Michael acceptor group is derived from vinyl sulfone and has the structure of formula (12):

<img file="RU2672103C2_D0023.tif" he="7" wi="124" img-format="jpg" img-content="undefined" />

in which each r^sixteen independently selected from hydrogen and C_1-3 alkyl. In some embodiments of Formula (12), each R¹³ is hydrogen. In some embodiments, a bis (sulfonyl) alkanol containing polythioether with terminal Michael acceptor groups can be prepared, for example, by reacting a thiol-terminated bis polychlorothiol alkanol with a compound that has a Michael (alkonyl) alkanol, and a thiol reactive group, such as divinyl sulfone, in the presence of a phosphine catalyst. Reactions and compounds, Michael acceptor / polythioethers described in US 13 / 529,237, filed June 21, 2012, which is fully incorporated by reference.

In some embodiments, the Michael acceptor group is derived from a bis (sulfonyl) alkanol and has the structure of formula (13a) or formula (13b):

<img file="RU2672103C2_D0024.tif" he="7" wi="160" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0025.tif" he="6" wi="160" img-format="jpg" img-content="undefined" />

where each r^ten independently selected from C_1-3 alcandiyl.

In some embodiments, each -V includes an alkenyl-terminated group.

In some implementations of the adducts of formula (11) and formula (11a), each R⁶ independently selected from vinyl ketone, vinyl sulfone and quinone. In some implementations, all the groups that are Michael acceptors may be the same and in some embodiments, at least some of the groups that are Michael acceptors are different.

In some embodiments, each R⁶ independently is a bis (sulfonyl) alkanol group.

In some implementations of the adducts of formula (11) and formula (11a) each R⁶ independently derived from bis (sulfonyl) alkanol and has the structure of formula (13a) or formula (13b):

<img file="RU2672103C2_D0026.tif" he="8" wi="147" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0027.tif" he="6" wi="147" img-format="jpg" img-content="undefined" />

where each r^ten independently selected from C_1-3 alcandiyl.

In some embodiments of a sulfur-containing prepolymer with Michael accepting end groups, the prepolymer includes at least two vinylsulfonyl end groups.

In some implementations, the sulfur-containing prepolymer with Michael accepting end groups may have at least two vinyl sulphonyl end groups and in some embodiments, at least two terminal 1- (ethylenesulfonyl) -N- (vinylsulfonyl) alkanol groups.

In some embodiments, a compound having a Michael acceptor group and a group that reacts with end groups of a sulfur-containing polymer may be a bis (sulfonyl) alkanol having the formula R — CH₂-CH₂-S (O)₂-R^ten-CH (-OH) -R^ten-S (O)₂-CH = CH₂where R is a fragment having a terminal group that reacts with the terminal groups of the sulfur-containing polymer; and every r^ten independently selected from C_1-3 alcandiyl. In some embodiments, the bis (vinyl) alkanol is a bis (vinylsulfonyl) alkanol.

The sulfur-containing maleimide adducts of the present invention include at least two terminal maleimide groups. Sulfur-containing prepolymers and adducts include, for example, polythioethers, polysulfides, sulfur-containing polyformals, and combinations thereof. Examples of suitable polythioethers are disclosed, for example, in US 6,123,179. Examples of suitable polysulfides are disclosed, for example, in US 4,623,711. In some embodiments, the sulfur-containing maleimide adduct may be difunctional and in some embodiments, may have a functionality of more than 2, for example, 3, 4, 5, or 6. A sulfur-containing maleimide adduct may include a mixture of sulfur-containing maleimide adducts having different functionalities characterized by an average functionality of 2.05- 6, 2.1-4, 2.1-3, 2.2-2.8, and in some embodiments 2.4-2.6. Sulfur-containing maleimide adducts have, at least two terminal maleimide groups and in some embodiments have two terminal groups 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrol-2, 5-dione, in some embodiments, more than two terminal groups, for example, 3, 4, 5 or 6 terminal groups of 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione. The sulfur-containing maleimide adduct may comprise a combination of adducts having a different number of terminal groups of 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione characterized, for example, by an average functionality of 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrol-2,5-dione 2.05-6 , 2.1-4, 2.1-3, 2.2-2.8 and in some embodiments 2.4-2.6. 5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione, in some embodiments, more than two end groups, for example, 3, 4, 5 or 6 end groups 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione. The sulfur-containing maleimide adduct may comprise a combination of adducts having a different number of terminal groups of 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione characterized, for example, by an average functionality of 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrol-2,5-dione 2.05-6 , 2.1-4, 2.1-3, 2.2-2.8 and in some embodiments 2.4-2.6. 5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione, in some embodiments, more than two end groups, for example, 3, 4, 5 or 6 end groups 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione. The sulfur-containing maleimide adduct may comprise a combination of adducts having a different number of terminal groups of 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione characterized, for example, by an average functionality of 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrol-2,5-dione 2.05-6 , 2.1-4, 2.1-3, 2.2-2.8 and in some embodiments 2.4-2.6.

The double bond of maleimides can react with thiol groups at pH 6.5-7.5 and is more reactive than (meth) acrylates. At neutral pH, the reaction of maleimides with thiols is approximately 1000 times faster than the reaction of maleimides with amines. Improved compositions derived from maleimide resins have suitable thermomechanical stability and anti-flammability.

In some implementations, the sulfur-containing prepolymer with an end maleimide group includes a maleimide prepolymer of a polythioether characterized by a polythioether having at least two end maleimide groups, such as, for example, at least two end groups 1- (4- (4- ( 3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione.

In some embodiments, the Michael end acceptor groups are selected from 1,3-bis (vinylsulfonyl-2-propanol, 1,1 '- (methylenedi-4,1-phenylene) bismaleimide, or a combination thereof.

In some implementations of the prepolymers of formula (8a) and formula (8b), each R⁶ independently prepared from bismaleimide. In some embodiments, all terminal maleimide fragments may be the same, and in some embodiments, at least some terminal maleimide fragments are different. In some embodiments, each R⁶ is 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrole-2,5-dione.

In some embodiments, the sulfur-containing maleimide adduct includes a polythioether maleimide adduct, comprising:

(a) a main chain comprising the structure of the formula (6):

<img file="RU2672103C2_D0028.tif" he="9" wi="134" img-format="jpg" img-content="undefined" />

in which (i) each R^one independently selected from C_2-10 n-alkanediol group, C_3-6 branched alkanediyl group, C_6-8 cycloalkanediyl group, C_6-10 alkane cycloalkanyl group, heterocyclic group, - [(- CHR³-)_p-X-]_q(CHR³)_r-groups in which each R³ independently selected from hydrogen and methyl; (ii) each R² independently selected from C_2-10 n-alkanediol group, C_3-6 branched alkanediyl group, C_6-8 cycloalkanediyl group, C_6-14 alkane cycloalkanyl group, heterocyclic group and - [(- CH₂-)_p-X-]_q(CH₂)_r- groups; (iii) each X is independently selected from O, S, and -NR⁶- groups in which R⁶ selected from H and methyl group; (iv) m is in the range of 0-50; (v) n is an integer of 1-60; (vi) p is an integer of 2-6; (vii) q is an integer of 1-5; and (viii) r is an integer of 2-10; and

(b) at least two end groups that are Michael acceptors.

In some implementations of the compounds of formula (6) R^one is - [(- CHR³-)_p-X-]_q(CHR³)_r-, where each X is independently selected from -O- and -S-. In some embodiments, where R^one is - [(- CHR³-)_p-X-]_q(CHR³)_r-, each X is -O- and in some implementations, each X is -S-.

In some implementations of the compounds of formula (6) R^one is - [(- CH₂-)_p-X-]_q(CH₂)_r-, where each X is independently selected from -O- and -S-. In some embodiments, where R^one is - [(- CH₂-)_p-X-]_q(CH₂)_r-, each X is -O- and in some implementations, each X is -S-.

In some embodiments, R^one in the formula (6) is - [(- CH₂-)_p-X-]_q(CH₂)_r-, where p is 2, X is O, q is 2, r is 2, R² is ethanediyl, m is 2, n is 9.

The terminal maleimide group has the structure of formula (12):

<img file="RU2672103C2_D0029.tif" he="34" wi="98" img-format="jpg" img-content="undefined" />

The terminal bismaleimide fragment refers to a fragment having a terminal maleimide group. In some embodiments, the terminal maleimide group is derived from bismaleimide, such as a compound having a structure of formula (4a):

<img file="RU2672103C2_D0030.tif" he="34" wi="110" img-format="jpg" img-content="undefined" />

in which r^ten is a divalent organic moiety and the end group has the structure of formula (4b):

<img file="RU2672103C2_D0031.tif" he="33" wi="110" img-format="jpg" img-content="undefined" />

and is referred to in the description of the group 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrol-2,5-dione. In some embodiments, the terminal maleimide group is obtained from 1,1 ′ - (methylene di-4,1-phenylene) bismaleimide of formula (5a), also called 1,1 ′ - (methylenebis (4,1-phenylene) bis (1H-pyrrol- 2,5-dione), and the end group has the structure of formula (5b):

<img file="RU2672103C2_D0032.tif" he="33" wi="123" img-format="jpg" img-content="undefined" />

In some embodiments, the maleimide group includes a 1- (4- (4- (3-yl-2,5-dioxopyrrolidin-1-yl) benzyl) phenyl) -1H-pyrrol-2,5-dione group. In some embodiments, all terminal maleimide groups may be the same and in some embodiments, at least some of the terminal maleimide groups are different.

Other examples of compounds having two or more maleimide groups include ethylene bismaleimide; 1,6-bismaleimidohexane; 2,4-dimaleimidotoluene, N, N'-1,3-phenylenedimaleimide; 1,4-bis (maleimido) butane trimethylene bismaleimide; p, p'-dimaleimidophenylmethane; 1H-pyrrole-2,5-dione pentamethylene bismaleimide; 1,1 '- (1,8-octanediyl) bis-1H-pyrrole-2,5-dione, 1,1' - (1,7-heptanediyl) bis-4,4'-dithiobis (phenyl maleimide); methylenebis (N-carbamylmaleimide), 1,9-bis (maleimide) nonane; 1,1'-decane-1,10-diylbis (1H-pyrrole-2,5-dione); O-phenylenediamine-indimide, bis (N-maleimidomethyl) ether; 1,5-bis (maleimide) -2-methyl-pentane; N, N'-1,4-phenylenedimaleimide; 1,1 '- (2-methyl-1,3-phenylene) bis (1H-pyrrole-2,5-dione); Kerimid 601 resins; tetrakis- (N-2-aminoethylmaleimide); 1- (2,5-dimethylphenyl) pyrrole-2,5-dione; SureCN331305, SureCN349749; or 1,1'-diphenyl-4,4 '

To obtain a sulfur-containing prepolymer with Michael accepting end groups, a sulfur-containing polymer, such as described in the application, can be brought into contact with a compound having a Michael acceptor group and a group that reacts with the sulfur-containing prepolymer end groups.

In some embodiments, the Michael acceptor group is selected from vinyl ketone, vinyl sulfone, maleimide, and quinone. In some embodiments, the Michael acceptor group is vinyl ketone and in some embodiments vinyl sulfone, such as that derived from divinyl sulfone. In some embodiments, in which a compound having a Michael acceptor group is derived from divinyl sulfone, the sulfur-containing polymer may be thiol-terminated, such as thiol-terminated polythioether, thiol-terminated polysulfide or a combination thereof.

In some embodiments, the Michael acceptor group is a bis (sulfonyl) alkanol, such as a group derived from a bis (vinylsulfonyl) alkanol. In some embodiments, in which a compound having a Michael acceptor group is derived from a bis (vinylsulfonyl) alkanol, the sulfur-containing polymer may be with thiol-terminated groups, such as thiol-terminated polythioether, thiol-terminated polysulfide, or a combination of these.

The reaction between the sulfur-containing polymer and the compound having a Michael acceptor group and a group that can react with the end group of the sulfur-containing polymer can be carried out in the presence of a suitable catalyst.

In some embodiments, compositions of the present invention include a catalyst, such as an amine catalyst. For example, in some implementations, in which the sulfur-containing polymer has terminal thiol groups, and the compound is a dysfunctional Michael acceptor, the reaction can take place in the presence of an amine catalyst. Examples of suitable amine catalysts include, for example, triethylenediamine (1,4-diazabicyclo [2.2.2] octane, DABCO), dimethylcyclohexylamine (DMCHA), dimethylethanolamine (DMEA), bis (2-dimethylaminoethyl) ether, N-ethylmorpholine, triethylamine, 1,8-Diazabicyclo [5.4.0] undecen-7 (DBU), pentamethyldiethylenetriamine (PMDETA), benzyldimethylamine (BDMA), N, N, N'-trimethyl-N'-hydroxyethyl-bis (aminoethyl) ether, and N ' - (3- (dimethylamino) propyl) -N, N-dimethyl-1,3-propanediamine.

In some embodiments, the sulfur-containing prepolymer with Michael acceptor end groups includes a urethane-containing prepolymer with Michael end acceptor groups. Urethane-containing prepolymers with end groups that are Michael acceptors are disclosed in the US patent application entitled "Fuel-resistant Urethane-containing prepolymers with end groups that are Michael acceptors and their compositions" on behalf of Keledjian, Ito and Lin, filed simultaneously with this application, which is completely included by reference.

Urethane-containing prepolymers with Michael accepting end groups include urethanes introduced into the main chain of the sulfur-containing prepolymer. Acceptor Urethane-containing prepolymers with Michael accepting end groups are suitable for creating hardened sealants with increased tensile strength.

For some applications, urethane-containing prepolymers with end groups that are Michael acceptors are an improvement over the previously disclosed sulfur-containing prepolymers with end groups that are Michael acceptors, such as those described in US 13 / 529,237 and 13 / 659,152. Cured sealants obtained from urethane-containing prepolymers with end groups that are Michael acceptors are characterized by increased tensile strength and surface adhesion compared to sulfur-containing prepolymers with end groups that are Michael acceptors disclosed in these applications. Increased tensile strength is believed to be obtained by incorporating urethane segments into the polymer backbone, and improved surface adhesion is believed

Urethane-containing prepolymers with Michael acceptor end groups include a urethane- and sulfur-containing backbone with terminal isocyanate groups, which are additionally substituted by Michael acceptor groups.

Urethane-containing prepolymers with terminal Michael acceptor groups include polythioethers, polysulfides, and combinations thereof.

It should be understood that urethane-containing prepolymers with Michael accepting end groups can be synthesized in several ways. The functional groups of the precursors can be adapted and selected for a particular chemical reaction. For example, in some embodiments, it may be appropriate for the sulfur-containing prepolymer to include thiol or hydroxyl functional groups. In embodiments where the sulfur-containing prepolymer has functional hydroxyl groups, the diisocyanate can directly interact with the sulfur-containing prepolymer. In implementations in which the precursor of the sulfur-containing prepolymer has terminal thiol groups, thiol groups can be substituted with a compound with hydroxyl functional groups to obtain a sulfur-containing prepolymer with terminal hydroxyl groups,

In some embodiments, a urethane-containing prepolymer with Michael acceptor end groups includes a urethane-containing prepolymer with Michael end acceptor, formula (13a), a urethane-containing prepolymer with Michael acceptor end groups, formula (13b), or a combination of these:

<img file="RU2672103C2_D0033.tif" he="13" wi="160" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0034.tif" he="14" wi="160" img-format="jpg" img-content="undefined" />

in which,

w is an integer of 1-100;

every r¹³ independently includes C_2-10 alkanediyl;

every r²⁰ independently includes a diisocyanate core;

every r^thirty independently includes at least one end group that is a Michael acceptor;

every r⁵⁰ independently includes a core of sulfur-containing prepolymer;

every r⁶⁰ independently includes a fragment having the structure of formula (14):

<img file="RU2672103C2_D0035.tif" he="7" wi="150" img-format="jpg" img-content="undefined" />

B represents the core of a z-valent polyfunctionalizing agent B (-V)_z, wherein,

z is an integer of 3-6; and

each V is a fragment that includes a terminal group that reacts with a thiol group; and

each -V'- is obtained by the reaction of -V with thiol.

In some embodiments, each R⁵⁰ is obtained from a polythioether and has the structure of formula (6):

<img file="RU2672103C2_D0036.tif" he="9" wi="134" img-format="jpg" img-content="undefined" />

wherein,

every r^one independently selected from C_2-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-14 alkancycloalkandiyl, C_5-8 heterocycloalkandiyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r-,

Where

s is an integer of 2-6;

q is an integer of 1-5;

r is an integer of 2-10;

every r³ independently selected from hydrogen and methyl; and

each X is independently selected from -O-, -S-, -NR- and -N (CH₃) -;

every r² independently selected from C_1-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-14 alkancycloalkanediyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r-, where s, q, r, R³ and X are as defined for R^one;

m is an integer of 0-50;

n is an integer of 1-60; and

p is an integer of 2-6.

In some embodiments, a urethane-containing prepolymer with Michael acceptor end groups is prepared by reacting a sulfur-containing prepolymer with thiol end groups, hydroxyvinyl ether, diisocyanate and 1,3-bis (vinylsulfonyl) -2-propanol (HO-CH (-CH₂-S (O)₂-CH = CH₂)₂), and optionally polyfunctionalizing agent. Thus, in some embodiments, a urethane-containing prepolymer with terminal Michael acceptor groups includes the structure of formula (15a), formula (15b), or combinations thereof.

<img file="RU2672103C2_D0037.tif" he="14" wi="160" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0038.tif" he="14" wi="160" img-format="jpg" img-content="undefined" />

in which each r¹³each r²⁰each r⁵⁰each r⁶⁰, w, z, B, and each -V'- are as defined in the description. In some implementations of formula (15a) and formula (15b), each R⁵⁰ has the structure of formula (6).

In some implementations of the prepolymers of formula (13a) and formula (13b), each R^thirty, includes the terminal maleimide group, and in some embodiments, the terminal bismaleimide group.

In some implementations, the urethane-containing prepolymer with Michael accepting end groups includes the reaction product of reagents, including the isocyanate-terminated urethane-containing adduct, and a compound that includes the isocyanate-reactive group and at least one Michael acceptor. In some implementations, urethane-containing prepolymers with Michael acceptor end groups of the present invention include the reaction product of reagents comprising an isocyanate-terminated urethane-containing adduct and a compound comprising a group that reacts with an isocyanate and at least one Michael acceptor group; and at least one ligand for the metal.

In some embodiments, a urethane-containing prepolymer with Michael acceptor end groups can be obtained by reacting an urethane-containing adduct with an isocyanate end group with a compound having at least one Michael acceptor group, and optionally a metal ligand group, and a group reactive with an isocyanate group, such as a hydroxy group. The reaction can take place at an appropriate temperature, for example, 50-100 ° C, for a suitable period of time, for example, 0.5-5 hours, in the presence of a suitable catalyst, such as dibutyl tin dilaurate.

In some embodiments, an urethane-containing adduct with terminal isocyanate groups includes an adduct of an urethane-containing polythioether with terminal isocyanate groups, an urethane-containing adduct of polysulfide with terminal isocyanate groups, or a combination thereof.

In some implementations, urethane-containing prepolymers with Michael acceptor end groups of the present invention may be blocked by a fragment having a group that reacts with an isocyanate and at least one Michael acceptor group. In some implementations, the terminal fragment further includes a ligand for the metal.

Groups reactive with isocyanate groups include hydroxyl groups, amino groups and thiol groups.

Michael acceptor groups are well known in the art. In some embodiments, the Michael acceptor group includes an activated alkene, such as an alkenyl group adjacent to an electron acceptor group, such as enone, nitro, halogen, nitrile, carbonyl, or nitro. In some embodiments, the Michael acceptor group is selected from vinyl ketone, vinyl sulfone, quinone, enamine, ketimine, aldimine, and oxazolidine. In some implementations, each of the groups that are Michael acceptors may be the same and in some embodiments, at least some of the groups that are Michael acceptors are different.

In some embodiments, the Michael acceptor group is vinyl sulfone, such as divinyl sulfone.

In some embodiments, each side chain of a urethane-containing prepolymer with terminal groups that are Michael acceptors may have 1-4 terminal groups that are Michael acceptors. In some embodiments, each side chain of a urethane-containing prepolymer with end groups that are Michael acceptors includes one end group that is Michael acceptors. In some embodiments, each side chain of a urethane-containing prepolymer with end groups that are Michael acceptors includes two end groups that are Michael acceptors.

In some implementations of formula (13a) and formula (13b), each R^thirty derived from bis (vinylsulfonyl) alkanol and has the structure of formula (16):

<img file="RU2672103C2_D0039.tif" he="8" wi="138" img-format="jpg" img-content="undefined" />

in which each r^ten is C_2-4-alcanidhplom.

In some embodiments, a compound containing an isocyanate-reactive group and at least one Michael acceptor group includes a bis (vinylsulfonyl) alkanol.

In some embodiments, the compound includes a hydroxyl group, and at least one group that is a Michael acceptor.

In some embodiments, urethane-containing prepolymers with Michael acceptor end groups of the present invention are blocked by a compound having a group that reacts with the isocyanate, at least one Michael acceptor group, and at least one ligand for the metal.

In some embodiments, the metal ligand is able to coordinate with the surface of aerospace technology.

In some embodiments, the compound includes a hydroxyl group and two vinylsulfonyl groups.

Particularly suitable compounds that include the two Michael acceptor groups, the metal ligand and the hydroxyl group are bis (vinylsulfonyl) alkanols. The terminal vinylsulfonyl groups are Michael acceptors, the bis (sulfonyl) groups serve as ligand for the metal and the hydroxyl group can react with the isocyanate groups of the urethane-containing adduct with the terminal isocyanate groups.

In some embodiments, a compound comprising a group that reacts with an isocyanate, at least one Michael acceptor group, and at least one ligand for a metal includes a bis (vinylsulfonyl) alkanol, and in some embodiments 1,3-bis ( Vinyl sulfonyl) -2-propanol.

In some implementations, urethane-containing prepolymers with Michael acceptor end groups of the present invention have terminal fragments comprising at least one Michael acceptor group and optionally at least one ligand for the metal and bound to the prepolymer isocyanate groups urethane bond.

Thus, in some embodiments, a Michael acceptor / ligand compound for a metal includes a reactive hydroxyl group capable of reacting with the isocyanate end groups of the precursor of the urethane-containing adduct with the isocyanate end groups.

In a previous paper, the inventors have shown that the introduction of metal ligands into the main chain of a sulfur-containing prepolymer and / or the presence of a terminal metal ligand for a sulfur-containing prepolymer can improve the adhesion of coatings and sealants on metal surfaces formed using metal-ligand prepolymers.

Bis (sulfonyl) alkanols are one type of metal ligand that can be incorporated into the polymer backbone or form an end group, for example, a sulfur-containing prepolymer to improve surface adhesion. Other metal ligands may also be incorporated into the polymer backbone to improve surface adhesion. In some embodiments, for example, for aerospace application of sealants, metal ligands may be selected from a ligand capable of coordinating aluminum, alumina, Al (III), anodized aluminum, titanium, titanium oxide, and / or Alodine® surfaces. A ligand for a metal can form a bidentate, tridentate or higher order coordination complex with surface atoms.

Ligands for metal and, in particular, ligands for aluminum (III) include rigid Lewis bases, such as —OH, —PO_four, -SO_four, -COOH, -C = O, and -NH₂ groups that are able to donate electrons to vacant metal orbitals. The main donor groups effective in forming multidentate coordination complexes with aluminum (III) include anions of aliphatic monohydroxy acids, catecholates, anions of aromatic hydroxy acids, 3-hydroxy-4-pyridinones, hydroxamates, and 3-hydroxy-2-pyridinones. Stable are complexes of aluminum (III) with multidentate ligands having negative oxygen as electron donors. A ligand for a metal may form a polydentate complex, such as a bidentate or tridentate complex with a metal.

In some embodiments, a functional group that is a ligand for a metal is derived from a chelating agent selected from bis (sulfonyl) alkanoyl, hydroxypyridinone and acetylacetonate.

Examples of a chelating agent for aluminum, aluminum oxide and Al (III) include 2,3-dihydroxybenzoic acid, 5-nitrosalicylate, 3-hydroxy-4-pyridinone, 3-hydroxy-2-pyridinone, 2-2'-dihydroxyazobenzene, 8 -oxyquinoline, oxylate, malonate, citrate, iminodiacetic acid, picolinic acid, maltol, kojic acid, N, N'-diacetic acid (EDTA), N- (2-hydroxy) ethylenediaminetetraacetic acid (GEDTC), ethylenediamine-α-ethylenediaminetetraacetic acid (GEDTC), ethylenediamine-α-ethylenediaminetetraacetic acid (HEDTC), ethylenediamine-α-ethylenediaminetetraacetic acid (HEDTA), ethylenediamine-α-DTA, ethylenediamine-α-diamine-ethylenediaminetetraacetic acid (HEDTA), ethylenediamine-α-EDTA, ethylenediamine-α-ethylenediaminetetratic acid α-bis (2-hydroxyphenylacetic acid (EDDHA), and N, N'-bis (hydroxybenzyl) ethylenediamine-N, N'-diacetic acid (HBED), acetoacetic acid, acetylaceto nat, catecholate, hydroxamate and quinone Other chelating agents for aluminum and aluminum oxide are disclosed, for example, in Yokel, Coordination Chemistry Reviews 2002, 228, 97-113; and in Martell et al., Coordination Chemistry Reviews 1996, 149, 311- 328.

Examples of ligands for metallic titanium or titanium oxide include H₂ABOUT₂, acetylacetonate (CH₂(COCH₃)₂), EDTA, trans-1,2-cyclohexanediaminetetraacetic acid, glycol ether diamine tetraacetic acid (GEDTA, (CH₂OCH₂CH₂N (CH₂COOH)₂)₂), diethylenetriaminepentaacetic acid (DTPA, HOOCH₂N (CH₂CH₂N (CH₂COOH)₂)₂), nitrilotriacetic acid (NTA, N (CH₂COOH)₃, salicylic acid, lactic acid, acetylacetonate, triethanolamine, and combinations thereof.

In some implementations, the ligand for the metal includes at least two heteroatomic groups capable of coordinating with the aluminum (III) surface. In some implementations, the ligand for the metal includes at least two heteroatomic groups selected from -OH, -PO_four-R (O)₂-, -SO_four, -S (O)₂-, -COOH, -C = O, -NH₂, -NH-, and a combination of any of the above.

In some embodiments, the functional group in the form of a ligand for a metal includes a moiety selected from formula (17a), formula (17b), formula (17c), formula (17d), formula (17e), and combinations of these:

<img file="RU2672103C2_D0040.tif" he="7" wi="126" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0041.tif" he="6" wi="127" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0042.tif" he="7" wi="138" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0043.tif" he="7" wi="126" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0044.tif" he="8" wi="113" img-format="jpg" img-content="undefined" />

in which —X— is independently selected from —C (O) - or —S (O)₂-; each s is independently selected from 1, 2 and 3; and R^five is C_1-3 alkanediyl. In some embodiments, each X is —C (O) - and each s is 1; and in some embodiments, each X is -S (O)₂- and each s is equal to 1.

In some embodiments, the ligand for the metal includes bis (sulfonyl) alkanoyl, hydroxypyridinone, quinone, acetylacetonate, or a combination thereof.

In some embodiments, an urethane-containing adduct with terminal isocyanate groups includes an adduct of an urethane-containing polythioether with terminal isocyanate groups, an adduct of an urethane-containing polysulf with terminal isocyanate groups, or a combination thereof.

In some embodiments, an urethane-containing adduct with terminal isocyanate groups includes an urethane-containing adduct with terminal isocyanate groups of formula (18a), a urethane-containing adduct with terminal isocyanate groups of formula (18b), or a combination of these:

<img file="RU2672103C2_D0045.tif" he="13" wi="160" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0046.tif" he="14" wi="160" img-format="jpg" img-content="undefined" />

in which,

w is an integer of 1-100;

every r¹³ independently includes C_2-10 alkanediyl;

every r²⁰ independently includes a diisocyanate core;

every r^thirty independently includes at least one end group that is a Michael acceptor;

every r⁵⁰ independently includes a core of sulfur-containing prepolymer;

every r⁶⁰ independently includes a fragment having the structure of formula (14):

<img file="RU2672103C2_D0047.tif" he="8" wi="147" img-format="jpg" img-content="undefined" />

B represents the core of a z-valent polyfunctionalizing agent B (-V)_z, wherein,

z is an integer of 3-6; and

each V is a fragment that includes a terminal group that reacts with a thiol group; and

each -V'- is obtained by the reaction of -V with thiol.

In some embodiments of formulas (18a) and (18b), each R⁵⁰ derived from a polythioether. For example, in some embodiments, each R⁵⁰ has the structure of formula (6):

<img file="RU2672103C2_D0048.tif" he="8" wi="135" img-format="jpg" img-content="undefined" />

wherein

every r^one independently selected from C_2-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-14 alkancycloalkandiyl, C_5-8 heterocycloalkandiyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r- where

s is an integer of 2-6;

q is an integer of 1-5;

r is an integer of 2-10;

every r³ independently selected from hydrogen and methyl; and

each X is independently selected from -O-, -S-, -NR-, and where R is selected from hydrogen and methyl;

every r² independently selected from C_1-10 alkanediyl, С_6-8 cycloalkandiyl, C_6-14 alkancycloalkanediyl and - [(- CHR³-)_s-X-]_q- (- CHR³-)_r-, where s, q, r, R³ and X are as defined for R^one;

m is an integer of 0-50;

n is an integer of 1-60; and

p is an integer of 2-6.

In some embodiments of formulas (18a) and (18b), w is an integer of 2-50, and in some embodiments, 2-20.

In some embodiments, an urethane-containing adduct with terminal isocyanate groups includes the reaction product of reagents, including a sulfur-containing adduct with terminal hydroxyl groups, and a diisocyanate.

In some implementations, the sulfur-containing adduct with terminal hydroxyl groups and the diisocyanate interact in a molar ratio such that the urethane-containing adduct with terminal isocyanate groups includes alternating units of the sulfur-containing fragment and the diisocyanate. In some embodiments, an urethane-containing adduct with terminal isocyanate groups includes the reaction product of reagents, including Permapol® 3.1E with terminal hydroxyl groups, and a diisocyanate, such as cycloaliphatic diisocyanate.

Urethane-containing adducts with terminal isocyanate groups can be synthesized by reacting, for example, a diisocyanate with a sulfur-containing adduct with corresponding terminal groups, such as, for example, a sulfur-containing adduct with terminal hydroxyl groups at a suitable temperature, for example, 50-100 ° C for a suitable time, for example , 1-4 hours in the presence of a free radical catalyst, such as 2,2'-azobis (2-methylbutyronitrile). Specialists in this field can determine the appropriate reaction conditions.

In some embodiments, the sulfur-containing adducts of the present invention include terminal hydroxyl groups, which react with isocyanate groups and can directly react with a polyisocyanate, such as diisocyanate, to produce urethane-containing adducts with terminal isocyanate groups, suitable for making urethane-containing prepolymers with a combination of a subject that is used by the developers and a group of developers who are subject to a group or a group of developers. according to the present invention.

In some implementations, the sulfur-containing adduct can be functionalized to obtain groups sufficiently reactive with isocyanate groups. For example, in some embodiments, sulfur-containing thiol-terminated adducts provide suitable precursors for the formation of urethane-containing prepolymers with Michael-acceptor end groups of the present invention. In some embodiments, a thiol-terminated sulfur-containing adduct can interact with a compound having a group that is reactive with respect to the alkenyl group and the hydroxyl group. Examples of such compounds include vinyl esters of hydroxy acids.

In some embodiments, a hydroxyl-terminated sulfur-containing adduct includes an hydroxyl-terminated polythioether adduct, such as an hydroxyl-terminated polythioether adduct of the formula (19a), a hydroxyl-terminated polythioether adduct of the formula (19b), or a combination of these.

<img file="RU2672103C2_D0049.tif" he="8" wi="142" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0050.tif" he="18" wi="141" img-format="jpg" img-content="undefined" />

in which R^oneR², m, n and p are defined in the description, and each R⁶ represents a fragment comprising a terminal hydroxyl group.

In some embodiments, each R⁶ derived from hydroxyvinyl ether and has the structure of formula (20):

<img file="RU2672103C2_D0051.tif" he="8" wi="125" img-format="jpg" img-content="undefined" />

where r¹³ is C_2-10 alkanediyl. In some embodiments, R¹³ is - (CH₂)_four-.

Urethane-containing adducts with terminal isocyanate groups can be obtained by reacting a polyisocyanate with a sulfur-containing adduct that includes terminal groups that react with isocyanate groups, such as terminal hydroxyl groups. The polyisocyanate can be difunctional, p-functional, where n is an integer of 3-6 or a combination of both. In some embodiments, the polyisocyanate is difunctional and is called a diisocyanate. The diisocyanate can be aliphatic, alicyclic or aromatic.

Examples of suitable aliphatic diisocyanates include, 1,6-hexamethylene diisocyanate, 1,5-diisocyanato-2-methylpentane, methyl 2,6-diisocyanatohexanoate, bis (isocyanatomethyl) cyclohexane, 1,3-bis (isocyanatomethyl) cyclohexane, 2,2, 4-trimethylhexane-1,6-diisocyanate, 2,4,4-trimethylhexane-1,6-diisocyanate, 2.5 (6) -bis (isocyanatomethyl) cyclo [2.2.1.] Heptane, 1,3,3- trimethyl-1- (isocyanatomethyl) -5-isocyanatocyclohexane, 1,8-diisocyanato-2,4-dimethyloctane, octahydro-4,7-methano-1H-indyndimethyldiisocyanate and 1,1'-methylenebis (4-isocyanatocyclohexane) and 4, 4-methylenedicyclohexyl diisocyanate) (H12MDI). Examples of suitable aromatic diisocyanates include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,6-toluene diisocyanate (2,6-TDI), 2,4-toluene diisocyanate (2,4-TDI), a mixture of 2,4-TDI and 2,6-TDI, 1,5-diisocyanatonaphthalene, diphenyloxide-4,4'-diisocyanate, 4,4 '

Examples of suitable alicyclic diisocyanates of which may be selected diisocyanates include isophorone diisocyanate, cyclohexane diisocyanate, metiltsiklogeksandiizotsianat, bis (isocyanatomethyl) cyclohexane, bis (isocyanatocyclohexyl) methane, bis (isocyanatocyclohexyl) -2,2-propane, bis (isocyanatocyclohexyl) -1,2 -ethane, 2-isocyanatomethyl-3- (3-isocyanatopropyl) -5-isocyanatomethyl-bicyclo [2.2.1] heptane, 2-isocyanatomethyl-3- (3-isocyanatopropyl) -6-isocyanatomethyl-bicyclo [2.2.1] heptane , 2-isocyanatomethyl-2- (3-isocyanatopropyl) -5-isocyanatomethyl-bicyclo [2.2.1] g ptan, 2-isocyanatomethyl-2- (3-isocyanatopropyl) -6-isocyanatomethyl-bicyclo [2.2.1] heptane, 2-isocyanatomethyl-3- (3-isocyanatopropyl) -6- (2-isocyanatoethyl) bicyclo [2.2.1 ] heptane, 2-isocyanatomethyl-2- (3-isocyanatopropyl) -5- (2-isocyanatoethyl) bicyclo [2.2.

Examples of suitable aromatic diisocyanates in which the isocyanate groups are not directly bonded to the aromatic ring include, but are not limited to, bis (isocyanatoethyl) benzene, α, α, α ', α'-tetramethylxylene diisocyanate, 1,3-bis (1-isocyanato -1-methylethyl) benzene, bis (isocyanatobutyl) benzene, bis (isocyanatomethyl) naphthalene, bis (isocyanatomethyl) diphenyl ether, bis (isocyanatoethyl) phthalate and 2,5-di (isocyanatomethyl) furan. Aromatic diisocyanates containing isocyanate groups bonded directly to the aromatic ring include phenylene etilfenilendiizotsianat, izopropilfenilendiizotsianat, dimetilfenilendiizotsianat, detilfenilendiizotsianat, diizopropilfenilendiizotsianat, naphthalene, metilnaftalindiizotsianat, biphenyl, 4,4'-diphenylmethane diisocyanate, bis (3-methyl-4-isocyanatophenyl) methane,

Other examples of suitable diisocyanates include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,6-toluene diisocyanate (2,6-TDI), 2,4-toluene diisocyanate (2,4-TDI), a mixture of 2,4-TDI and 2,6-TDI, 1,5-diisocyanatonaphthalene, diphenyloxide-4,4'-diisocyanate, 4,4'-methylenediphenyl diisocyanate (4,4-MDI), 2,4'-methylenediphenyl diisocyanate (2,4-MDI), 2 , 2'-diisocyanatodiphenylmethane (2,2-MDI), diphenylmethane diisocyanate (MDI), 3,3'-dimethyl-4,4'-biphenylenisisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, 1 - [(( 2,4-diisocyanatophenyl) methyl] -3-isocyanato-2-methylbenzene, 2,4,6-triisopropyl-m-phenylene diisocyanate, 4,4-methyl ditsiklogeksildiizotsianat (H12MDI), and combinations thereof.

Additional examples of suitable aromatic diisocyanates include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,6-toluene diisocyanate (2,6-TDI), 2,4-toluene diisocyanate (2,4-TDI), a mixture of 2,4-TDI and 2,6-TDI, 1,5-diisocyanatonaphthalene, diphenyloxide-4,4'-diisocyanate, 4,4'-methylenediphenyl diisocyanate (4,4-MDI), 2,4'-methylenediphenyl diisocyanate (2,4-MDI), 2,2'-diisocyanatodiphenylmethane (2,2-MDI), diphenylmethane diisocyanate (MDI), 3,3'-dimethyl-4,4'-biphenylenisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, 1- [ (2,4-Diisocyanatophenyl) methyl] -3-isocyanato-2-methylbenzene and 2,4,6-triisopropyl-m-phenyl edeisocyanate.

Urethane-containing adducts with terminal isocyanate groups can be obtained, for example, by reacting a sulfur-containing adduct with terminal hydroxyl groups, such as a hydroxy-terminal polythioether of formula (12a) and formula (12b) with a compound with a terminal isocyanate group and a group that can react with the ends the hydroxyl groups of the polythioethers of formula (19a) and formula (19b), such as diisocyanate.

In some implementations, urethane-containing polythioether adducts with terminal isocyanate groups can be prepared, for example, by reacting the polythioether adduct with terminal hydroxyl groups of formula (19a) or formula (19b) with a diisocyanate, such as TDI, Isonate ™ 143L (diphenylmethanediococyansthenate, and an anhydrometocyanmate) process.^® N3400 (1,3-diazetidin-2,4-dione, 1,3-bis (6-isocyanatohexyl) -), IDPI (isophorone diisocyanate), or Desmodur^® W (H12MDI) optionally in the presence of a catalyst, such as dibutyl tin dilaurate in an organic solvent, such as benzoyl chloride, at a temperature of about 70-80 ° C to obtain the corresponding urethane-containing adduct of a polythioether with terminal isocyanate groups of the formula (13a), (13b), (15a ) and (15b).

In some implementations, the fragment-C (= O) -NH-R²⁰-NH-C (= O) - can be obtained from a diisocyanate of the formula (21):

<img file="RU2672103C2_D0052.tif" he="8" wi="87" img-format="jpg" img-content="undefined" />

In some embodiments, a hydroxyl-terminated sulfur-containing adduct includes the reaction product of reagents, including a thiol-terminated sulfur-containing adduct and hydroxyvinyl ether.

In some embodiments, a thiol-terminated sulfur-containing prepolymer includes a thiol-terminated polythioether prepolymer, a thiol-terminated polysulfide prepolymer, or a combination thereof.

Suitable thiol-terminated sulfur-containing prepolymers for use in preparing Michael-acceptor urethane-containing prepolymers with end groups include any thiol-terminated sulfur-containing polymers of formula (6), formula (7a) and formula (7b).

In some embodiments, a hydroxyl-terminated sulfur-containing adduct can be obtained by reacting a thiol-terminated sulfur-containing adduct with hydroxyvinyl ether.

In some embodiments, hydroxyvinyl ethers can be used to functionalize a sulfur-containing thiol-terminated adduct with a group that reacts with an isocyanate group. In some implementations, hydroxy-functionalized vinyl ether has the structure of formula (22):

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in which t is an integer of 2-10.

Examples of suitable hydroxyl-functional vinyl esters suitable for reaction with sulfur-containing thiol-terminated prepolymers include 1,4-cyclohexanedimethyl monovinyl ether, 1-methyl-3-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, and a combination thereof. In some embodiments, the hydroxy functional vinyl ester is 4-hydroxybutyl vinyl ether.

In some embodiments, urethane-containing prepolymers with end groups that are Michael acceptors can be obtained by a three-step reaction. The sequence of reactions includes the preparation of an urethane-containing adduct with terminal isocyanate groups, followed by blocking terminal isocyanate groups by a Michael's multifunctional acceptor. Specialists in this field of technology it is clear that other chemical reactions can be used for the synthesis of the disclosed urethane-containing prepolymers with terminal groups, which are Michael acceptors. For example, instead of using a thiol-terminated sulfur-containing prepolymer, a sulfur-containing alkenyl-containing prepolymer can be used and is associated with a polyisocyanate diamine. Thus, appropriate synthesis methods, starting materials and intermediates provided

In the first stage, a thiol-terminated sulfur-containing adduct can be reacted with hydroxyvinyl ether to produce a hydroxyl-terminated sulfur-containing adduct. The reaction can be carried out at elevated temperature in the presence of a free radical initiator.

In the second stage, a sulfur-containing adduct with hydroxyl end groups can be reacted with a polyisocyanate, such as a diisocyanate, to produce an urethane-containing adduct with end isocyanate groups. The reaction can be carried out at elevated temperature in the presence of a tin-based catalyst.

In the third stage, an urethane-containing adduct with terminal isocyanate groups can be brought into contact with a polyfunctional Michael acceptor to produce a polyfunctional urethane-containing prepolymer with terminal Michael-acceptors of the present invention. The reaction can be carried out at elevated temperature in the presence of a tin-based catalyst.

An example of a suitable reaction sequence is as follows:

<img file="RU2672103C2_D0054.tif" he="77" wi="160" img-format="jpg" img-content="undefined" />

<img file="RU2672103C2_D0055.tif" he="15" wi="124" img-format="jpg" img-content="undefined" />

where r¹³R²⁰R^thirtyR⁵⁰ and R⁶⁰ defined in the description. An exemplary reaction sequence is shown in FIG. 1. The sequence of reactions shown above and in FIG. 1 (indicated by Fig. Is in another application - 1611433), begins with the reaction of dithiol. In some embodiments, the reaction may begin with a reaction of a polythiol, such as tritiol, or a mixture of polythiols, such as a combination of dithiols and tritiols.

The compositions of the present invention include one or more phosphine catalysts, such as tertiary phosphine based catalysts.

In some implementations of the invention, the phosphine catalyst has the structure of formula (23):

<img file="RU2672103C2_D0056.tif" he="7" wi="124" img-format="jpg" img-content="undefined" />

where r^oneR² and R³ each is independently selected from C_1-12 alkyl substituted With_1-12 alkyl, C_6-12 aryl, substituted With_6-12 aryl, C_3-12 cycloalkyl substituted With_3-12 cycloalkyl, C_6-12 arylalkyl and substituted C_6-12 arylalkyl. In some embodiments, R^oneR² and R³ independently selected from C_1-6 alkyl and hydroxy-substituted C_1-6 alkyl. In some embodiments, R^oneR² and R³ independently selected from C_1-6 alkyl and in some embodiments n-hydroxyl-substituted C_1-6 alkyl.

In some implementations, the phosphine catalyst comprises a trisubstituted phosphine, having at least one batchwhich is an alkyl group. The remaining phosphine substituents may be any combination of aryl, cycloalkyl and / or alkyl groups. For example, two phosphine substituents may be alkyl groups having four or more carbon atoms, often six or more carbon atoms, and one substituent may be an aryl group. Alternatively, all three substituents may be alkyl groups, such as alkyl groups having six or more carbon atoms. Suitable examples include tributyl phosphine catalyst, triizobutilfosfin, tri-tert-butylphosphine, trioctylphosphine, tris (2,4,4-trimethylpentyl) phosphine, tritsiklopentilfosfin, tricyclohexylphosphine, tri-n-oktilfosfin, tri-n-dodetsilfosfin, triphenylphosphine and dimetilfenilfosfin.

In some implementations, a suitable phosphine catalyst includes hydroxy-substituted C_1-6 alkyl phosphine catalyst, where each R^oneR² and R³ has a structure BUT- (CH₂)_n- where n is an integer of 1-6. In some embodiments, the phosphine catalyst is selected from tris (2-hydroxyethyl) phosphine, tris (3-hydroxypropyl) phosphine, tris (4-hydroxybutyl) phosphine, tris (5-hydroxypentyl) phosphine, and tris (6-hydroxyhexyl) phosphine.

Phosphine catalysts are commercially available or can be obtained in accordance with standard synthesis methods, such as the Grignard reactions of alkyl halides with phosphorus trichloride or the catalytic addition of alkenes to phosphine.

The phosphine catalyst can be used in an amount sufficient to allow the reactive functional groups in the reaction mixture to flow or accelerate. The amount may vary depending on the chemical composition of the reagents used, but as a rule, the amount of trisubstituted phosphine used in the method of the present invention is 0.1-10 weight percent relative to the total mass of solid resin in the reaction mixture.

The compositions of the present invention may additionally include one or more compounds that are Michael acceptors, and / or one or more polythiols.

When the composition includes a polyfunctional monomeric Michael acceptor, any suitable monomeric Michael acceptor having at least two Michael acceptor groups, such as, for example, divinyl sulfone or other Michael acceptors, including any disclosed in the description, can be used.

The compound, which is a polyfunctional Michael acceptor, has at least two groups, the Michael acceptor. Michael's multifunctional acceptor may have an average functionality of 2-6, 2-4, 2-3 Michael acceptors and 2.05-2.5 in some implementations. In some embodiments, the Michael polyfunctional acceptor is difunctional, such as, divinyl ketone and divinyl sulfone. A Michael acceptor compound with more than two functionality can be obtained by reacting a compound having a Michael acceptor group and a group that reacts with end groups of a polyfunctionalizing agent, such as those described in the description, using appropriate reaction conditions.

In some implementations, where a compound that is a Michael acceptor is used, the molecular weight of the Michael acceptor is less than 600 Daltons, less than 400 Daltons, and in some embodiments, less than 200 Daltons.

In some implementations, the connection, which is the Michael acceptor, is about 0.5-20% of the mass. composition, about 1-10 wt.%, about 2-8 wt.%, about 2-6% of the mass. and in some embodiments, about 3-5% by weight, where% by weight. given relative to the total weight of dry solids in the composition.

The polythiol may be a small molecule, such as a compound having a molecular weight of less than 400 daltons, a prepolymer, or a combination thereof. For example, the polythiol may be a dithiol of formula (16), such as, for example, DMDO, a polythiol of formula (18), or a combination of these.

The compositions of the present invention may include one or more additional components suitable for use in aerospace sealants and the choice and amount depends, at least in part, on the desired characteristics of the cured sealant under the conditions of use.

In some embodiments, the compositions of the present invention comprise one or more than one adhesion promoter. One or more adhesion promoters may be present in an amount of 0.1-15% by weight. composition, less than 5% of the mass., less than 2% of the mass. and in some implementations, less than 1% of the mass. relative to the total weight of the dry composition. Examples of adhesion promoters include phenolic resins such as Methylon® phenolic resins, and organosilanes, for example, epoxy, mercapto or amino functional silanes, such as Silquest® A-187 and Silquest® A-1100. Other suitable adhesion promoters are known in the art.

The compositions of the present invention may include one or more different types of filler. Suitable fillers include conventional fillers of the prior art, including inorganic fillers such as carbon black and calcium carbonate (CaCO₃), silica, polymer powders and lightweight fillers. Suitable lightweight fillers include, for example, the fillers described in US 6,525,168. In some implementations, the composition comprises 5-60% of the mass. filler or combination of fillers, 10-50% of the mass. and in some implementations 20-40% of the mass. relative to the total dry weight of the composition. The compositions of the present invention may additionally include one or more dyes, thixotropic additives, accelerators, flame retardants, adhesion promoters, solvents, masking agents, or a combination of these. As can be seen, the fillers and additives used in the composition can be chosen to be compatible with each other, as well as with the polymer component, the hardener and the catalyst.

In some embodiments, the compositions of the present invention include low density filler particles. In accordance with the use of the description of the low density with reference to such particles means that the specific gravity of the particles is not more than 0.7, in some implementations not more than 0.25 and in some implementations not more than 0.1. Suitable lightweight filler particles often fall into two categories - microspheres and amorphous particles. The specific gravity of the microspheres may be in the range of 0.1-0.7, and include, for example, polystyrene foam, polyacrylate and polyolefin microspheres, and silica microspheres with a particle size in the range of 5-100 μm and a specific weight of 0.25 (Eccospheres®). Other examples include alumina / silica microspheres with a particle size in the range of 5-300 μm and a specific gravity of 0.7 (Fillite®), aluminum silicate microspheres with a specific gravity of about 0.45-0.7 (Z-Light®), calcium carbonate microspheres coated with polyvinylidene copolymer, specific gravity 0.13 (Dualite® 6001AE), and calcium carbonate microspheres coated with acrylonitrile copolymer such as Dualite® E135, having an average particle size of about 40 microns and a specific weight of 0.135 g / cu. cm (Henkel). Fillers suitable for snowing the specific gravity of the composition include, for example, hollow microspheres, such as Expancel® microspheres (supplied by AkzoNobel) or Dualite® low density polymeric microspheres (supplied by Henkel). In some implementations, the compositions of the present invention include lightweight filler particles comprising an outer surface coated with a thin layer, for example, the particles described in US 2010/0041839 in paragraphs [0016] - [0052],

In some embodiments, the low density filler is less than 2% by weight. composition, less than 1.5% by weight, less than 1.0% by weight, less than 0.8% by weight, less than 0.75% by weight, less than 0.7% by weight and in some implementations less than 0.5% of the mass. composition, where% of the mass. given relative to the total dry weight of the solid composition.

Examples of electrically non-conductive fillers include materials such as, but without limitation, calcium carbonate, mica, polyamide, colloidal silicon dioxide, molecular sieve powder, microspheres, titanium dioxide, chalk, alkaline shales, cellulose, zinc sulfide, heavy spar, alkaline earth oxides alkaline earth hydroxides, etc. Fillers also include materials with a wide band gap, such as zinc sulfide and inorganic barium compounds. In some implementations, the electrically conductive base composition may include some amount of electrically non-conductive filler in the range of 2-10% by weight. relative to the total weight of the main composition and in some embodiments, it may be 3-7% by weight. In some implementations, the composition of the curing agent may include some amount of electrically non-conductive filler in the range of less than 6% of the mass. and in some implementations, 0.5% -4% of the mass. relative to the total weight of the composition curing agent.

Low density fillers can reduce the specific gravity of the composition. In some embodiments, the specific gravity of the composition is 0.8-1, 0.7-0.9, 0.75-0.85, and in some embodiments it is 0.8. In some embodiments, the specific gravity of the composition is less than about 0.9, less than about 0.8, less than about 0.75, less than about 0.7, less than about 0.65, less than about 0.6, and in some embodiments less than about 0 55

In some embodiments, the compositions of the present invention comprise an electrically conductive filler. Electrical conductivity and electromagnetic interference / interference shielding can be imparted to the composition by introducing conductive materials into the polymer. Conductive elements may include, for example, metallic or metallized particles, fabrics, nets, fibers, and combinations thereof. The metal may be, for example, in the form of fibers, particles, flakes or spheres. Examples of metals include copper, nickel, silver, aluminum, tin, and steel. Other conductive materials that can be used for shielding from electromagnetic interference / radio interference of polymer compositions include conductive particles or fibers, including carbon or graphite. Conductive polymers such as polythiophenes, polypyrroles, polyaniline, poly (p-phenylene) vinylene,

Fillers used for imparting electrical conductivity and shielding electromagnetic interference / radio interference of polymer compositions are well known in the art. Examples of electrically conductive fillers include electrically conductive fillers based on noble metals, such as pure silver; noble-metal noble metals such as silver plated with gold; noble-metal non-noble metals, such as silver-plated copper, nickel or aluminum, for example silver-clad cores of aluminum particles or copper particles coated with platinum; noble metal coated glass, plastic or ceramics, such as silver-plated glass microspheres, aluminum or plastic microspheres broken by the noble metal; mica; and other similar conductive fillers with noble metals. Non-precious metal materials can also be used and include, for example, non-precious metals coated with non-precious metals, such as copper-coated iron particles or nickel-coated copper; non-noble metals, such as copper, aluminum, nickel, cobalt; non-precious metal coated non-precious metals such as nickel-plated graphite and non-metallic materials such as carbon black and graphite. Combinations of electrically conductive fillers can also be used to achieve the desired conductivity, EMI shielding, hardness, and other properties suitable for a particular application. such as copper-coated iron particles or nickel-plated copper; non-noble metals, such as copper, aluminum, nickel, cobalt; non-precious metal coated non-precious metals such as nickel-plated graphite and non-metallic materials such as carbon black and graphite. Combinations of electrically conductive fillers can also be used to achieve the desired conductivity, EMI shielding, hardness, and other properties suitable for a particular application. such as copper-coated iron particles or nickel-plated copper; non-noble metals, such as copper, aluminum, nickel, cobalt; non-precious metal coated non-precious metals such as nickel-plated graphite and non-metallic materials such as carbon black and graphite. Combinations of electrically conductive fillers can also be used to achieve the desired conductivity, EMI shielding, hardness, and other properties suitable for a particular application.

The shape and size of the electrically conductive fillers used in the compositions of the present invention may be of any suitable shape and size to provide shielding from the hindrances / radio interference of the cured composition. For example, fillers can be of any shape that is commonly used in the manufacture of electrically conductive fillers, including spherical, flakes, plates, particles, powder, irregular, fibers, and the like. In some of the sealant compositions of the present invention, the base composition may include graphite with a Ni-coating in the form of particles, powder, or flakes. In some implementations, the amount of graphite with Ni-coating in the main composition may be 40-80% of the mass. and in some implementations may be 50-70% of the mass. relative to the total mass of the main composition. In some embodiments, the electrically conductive filler may comprise Ni fiber. Ni fiber can have a diameter in the range of 10-50 microns and a length in the range of 250-750 microns. The main composition may include, for example, the amount of Ni fiber in the range of 2-10% by weight. and in some implementations, 4-8 wt.%, relative to the total mass of the main composition.

Carbon fibers, in particular, graphitized carbon fibers, can also be used to impart electrical conductivity to the compositions of the present invention. Carbon fibers, formed by the method of pyrolysis in the vapor phase and graphitized by heat treatment, and which are hollow or solid with a fiber diameter in the range from 0.1 micron to several microns, have high electrical conductivity. As described in US 6,184,280, carbon microfiber, nanotubes or carbon fibrils having an outer diameter of less than 0.1 μm to tens of nanometers can be used as electrically conductive fillers. An example of graphitized fiber suitable for conductive compositions of the present invention includes PANEX® 30MF (Zoltek Companies, Inc., St. Louis, Mo), a round fiber with a diameter of 0.921 μm,

The average particle size of the electrically conductive filler may be in the range suitable for imparting electrical conductivity to the polymer-based composition. For example, in some embodiments, the particle size of one or more fillers may be 0.25-250 microns and in some embodiments may be 0.25-75 microns and in some embodiments, it may be 0.25-60 microns. In some implementations, the composition of the present invention may include Ketjen Black EC-600 JD (Akzo Nobel, Inc., Chicago, IL), electrically conductive carbon black, characterized by the absorption of iodine 1000-11500 mg / g (test method J0 / 84 -5) and pore volume 480-510 cm³/ 100 g (by absorption DBP, KTM 81-3504). In some embodiments, the conductive carbon black filler is Black Pearls 2000 (Cabot Corporation, Boston, Mass.).

In some embodiments, electrically conductive polymers may be used to impart or modify the electrical conductivity of the compositions of the present invention. Polymers having sulfur atoms included in aromatic groups or adjacent to double bonds, for example, in polyphenylene sulfide and polythiophene, are known to be electrically conductive. Other electrically conductive polymers include, for example, polypyrroles, polyaniline, poly (p-phenylene) vinylene, and polyacetylene. In some embodiments, the sulfur-containing polymers forming the base composition can be polysulfides and / or polythioethers. Thus, sulfur-containing polymers can include sulfur-containing aromatic groups and a sulfur atom adjacent to conjugated double bonds, such as vinylcyclohexene-dimercaptooxoctane,

The compositions of the present invention may include more than one electrically conductive filler and several electrically conductive fillers may be the same or different in material and / or shape. For example, a sealant composition may include electrically conductive Ni fibers and electrically conductive graphite with nickel coating in the form of powder, particles, or flakes. The number and type of electrically conductive filler can be selected to obtain a sealant composition which, when cured, has a surface resistance of the layer (four-point resistance) less than 0.50 Ω / cm² and in some embodiments, the surface resistance of the layer is less than 0.15 Ω / cm². The number and type of filler can also be chosen to provide effective shielding for electromagnetic interference / radio interference in the frequency range from 1 MHz to 18 GHz of the hole sealed by the sealant composition of the present invention.

Corrosion caused by the formation of micropairs of dissimilar metal surfaces and conductive compositions of the present invention can be minimized or prevented by adding corrosion inhibitors to the composition and / or selecting appropriate conductive fillers. In some embodiments, the corrosion inhibitors include strontium chromate, calcium chromate, magnesium chromate, and combinations thereof. US 5,284,888 and US 5,270,364 disclose the use of aromatic triazoles to inhibit corrosion of aluminum and steel surfaces. In some embodiments, a consumable oxygen scavenger such as Zn may be used as a corrosion inhibitor. In some implementations, the corrosion inhibitor may be less than 10% of the mass. the total mass of the conductive composition. In some implementations, the corrosion inhibitor may be 2-8% of the mass. the total mass of the conductive composition. Corrosion between dissimilar metal surfaces can also be minimized or prevented by choosing the type, amount, and properties of the conductive fillers included in the composition.

In some implementations, the sulfur-containing prepolymers with end groups that are Michael acceptors, and thiol-terminated prepolymers make up about 50-90% by weight. composition, about 60-90% wt., about 70-90% of the mass. and in some implementations, about 80-90% of the mass. composition, where% of the mass. are given relative to the total dry weight of the composition.

The compositions of the present invention can be used, for example, in sealing compositions, coatings, sealants and priming compositions. Sealant includes a composition that can provide a film that can withstand operating conditions, such as humidity and temperature, and at least partially block the transfer of materials, such as water, fuel, and other liquids and gases. The coating composition includes a coating that is applied to the surface of the substrate, for example, to improve the properties of the substrate, such as appearance, adhesion, wettability, corrosion resistance, wear resistance, resistance to fuel and / or abrasion resistance. The casting composition includes a material used in electronic units to provide resistance to shocks and vibrations and to exclude ingress of moisture and corrosive substances.

In some implementations, compositions, such as sealants, can be made in the form of multi-component compositions, such as two-component compositions, in which one package includes one or more components, including at least two end groups that react with Michael accepting groups, and the second package includes one or more Michael acceptors. Additives and / or other materials may be added to any package as necessary. Two packs can be combined and mixed before use. In some embodiments, the viability of the combined composition is at least 12 hours, at least 24 hours, at least 48 hours, and in some embodiments more than 48 hours.

In two-component compositions, one or more phosphine catalysts with controlled release can be included in any component or in both components. In some implementations, the controlled release catalyst may be a third component that is mixed with a thiol-terminated sulfur-containing prepolymer and a sulfur-containing Michael-acceptor prepolymer, prior to use. In some embodiments, the compositions are provided as a single component composition. Such one-component compositions are maintained and stored under conditions such that the controlled release catalyst is not substantially released. For example, a composition comprising a photosensitive catalyst may be protected from UV radiation, a catalyst released by moisture,

Compositions, including sealants of the present invention, may be applied to any of various substrates. Examples of substrates on which the composition may be applied include metals such as titanium, stainless steel and aluminum, which may be anodized, primed, organic coated or chromate coated; epoxy; urethane material; graphite; composite fiberglass; Kevlar®; acrylic materials; and polycarbonates. In some embodiments, the compositions of the present invention may be applied to a coating on a substrate, such as a polyurethane coating.

The compositions of the present invention can be applied directly to the surface of the substrate or to the sublayer using any suitable coating method known to those skilled in the art.

In addition, methods have been proposed for sealing the opening using the composition of the present invention. These methods include, for example, applying a composition of the present invention to a surface to seal a hole and curing the composition. In some embodiments, a method of sealing a hole includes (a) applying a sealant composition of the present invention to one or more surfaces defining a hole, (b) combining the surfaces defining a hole, and (c) curing the sealant to obtain a sealed hole.

In some embodiments, methods of using the composition of the present invention include applying the composition to a substrate; and curing the composition to obtain a cured sealant. In some implementations, methods for using the composition of the present invention include applying the composition to a substrate in which the phosphine catalyst comprises an encapsulated controlled-release phosphine catalyst; activation of the phosphine catalyst; and curing to obtain a cured sealant.

In some embodiments, the composition may be cured under ambient conditions, ambient conditions refer to a temperature of 20-25 ° C and atmospheric humidity. In some embodiments, the composition may be cured under conditions covering a temperature of 0-100 ° C and a humidity of 0-100% relative humidity. In some embodiments, the composition may be cured at a higher temperature, for example, at least 30 ° C, at least 40 ° C, and in some embodiments, at least 50 ° C. In some implementations, the composition may be cured at room temperature, for example, 25 ° C. In some embodiments, the composition may be cured by exposure to actinic radiation, such as ultraviolet radiation. As will also be clear

In some implementations, the composition achieves curing without tack-free in less than about 1 hour, less than about 2 hours, less than about 4 hours, less than about 6 hours and in some implementations less than about 412 hours, after the useful life of the composition.

The formation time of a suitable seal using the curable compositions of the present invention may depend on several factors, as can be understood by those skilled in the art and as determined by the requirements of the applicable standards and specifications. In general, the adhesive strength of the curable compositions of the present invention is achieved within 24-30 hours, and 90% of the total adhesive strength is achieved in 2-3 days after mixing and applying to the surface. In general, the full adhesive strength, as well as other properties of the cured compositions of the present invention, will be fully achieved within 7 days after mixing and applying a curable several surfaces defining the opening, (b) combining the surfaces defining the opening,

In some embodiments, methods of using the composition of the present invention include applying the composition to a substrate; and curing the composition to obtain a cured sealant. In some implementations, methods for using the composition of the present invention include applying the composition to a substrate in which the phosphine catalyst comprises an encapsulated controlled-release phosphine catalyst; activation of the phosphine catalyst; and curing to obtain a cured sealant.

In some embodiments, the composition may be cured under ambient conditions, ambient conditions refer to a temperature of 20-25 ° C and atmospheric humidity. In some embodiments, the composition may be cured under conditions covering a temperature of 0-100 ° C and a humidity of 0-100% relative humidity. In some embodiments, the composition may be cured at a higher temperature, for example, at least 30 ° C, at least 40 ° C, and in some embodiments, at least 50 ° C. In some implementations, the composition may be cured at room temperature, for example, 25 ° C. In some embodiments, the composition may be cured by exposure to actinic radiation, such as ultraviolet radiation. As will also be clear

In some implementations, the composition achieves curing without tack-free in less than about 1 hour, less than about 2 hours, less than about 4 hours, less than about 6 hours and in some implementations less than about 412 hours, after the useful life of the composition.

The formation time of a suitable seal using the curable compositions of the present invention may depend on several factors, as can be understood by those skilled in the art and as determined by the requirements of the applicable standards and specifications. In general, the adhesive strength of the curable compositions of the present invention is achieved within 24-30 hours, and 90% of the total adhesive strength is achieved in 2-3 days after mixing and applying to the surface. In general, full adhesion strength, as well as other properties of the cured compositions of the present invention, will be fully achieved within 7 days after mixing and applying a curable medium in JRF type 1. Other properties, ranges and / or threshold values ​​may be suitable for other applications of sealants .

In some implementations, therefore, the compositions of the present invention are resistant to fuel. In accordance with the use in the description of the term "resistant to fuel" means that the composition, when applied to a substrate and cured, can provide a cured product, for example, a sealant, the volume percent swelling of which is not more than 40%, in some cases not more than 25%, in some cases no more than 20%, in other cases no more than 10%, after immersion for one week at 140 ° F (60 ° C) and ambient pressure in a standard reactive liquid (JRF) type I in accordance with methods similar to those described in ASTM D792 (American public and for Testing and Materials) or AMS 3269 (specifications for aerospace materials). JRF Type I reactive standard fluid, used to determine the resistance to fuel, has the following composition: toluene: 28 ± 1% vol .; cyclohexane (technical): 34 ± 1% vol .; isooctane: 38 ± 1% vol .; and tertiary dibutyl disulfide: 1 ± 0,005% vol. (see AMS 2629, published July 1, 1989, § 3.1.1, etc., available at SAE (Society of Automotive Engineers)).

In some embodiments, the compositions of the present invention provide a cured product, for example in the form of a sealant, with a tensile elongation of at least 100% and a tensile strength of at least 400 psi when measured in accordance with the procedure described in AMS 3279 , § 3.3.17.1, test method AS5127 / 1, § 7.7.

In some embodiments, the compositions give a cured product, for example, a sealant with an overlap joint strength at shear of more than 200 psi, for example at least 220 psi, at least 250 psi and, in some cases, at least 400 psi, at measurement in accordance with the procedure described in SAE AS5127 / 1 paragraph 7.8.

In some implementations, the cured sealant comprising the composition of the present invention meets or exceeds the requirements for aerospace sealants provided for by AMS 3277.

Openings are also disclosed, including openings of aerospace vehicles sealed with compositions of the present invention.

In some embodiments, the electrically conductive sealant composition of the present invention has the following properties, measured at room temperature after being kept at 500 ° F for 24 hours: surface resistivity is less than 1 Ω / square, tensile strength is more than 200 psi, relative elongation is more than 100% , and 100% cohesive failure, measured in accordance with MIL-C-27725.

In some embodiments, the cured sealant of the present invention has the following properties after curing for 2 days at room temperature, 1 day at 140 ° F, and one day at 200 ° F: dry hardness 49, tensile strength of 428 psi and relative elongation of 266% ; and after 7 days in JRF, hardness 36, tensile strength of 312 psi and an elongation of 247%.

In some embodiments, the compositions of the present invention are characterized by a Shore A hardness (7 days of cure) of more than 10, more than 20, more than 30, and in some embodiments more than 40; tensile strength greater than 10 psi, more than 100 psi, more than 200 psi, and in some embodiments more than 500 psi; relative lengthening more than 100%), more than 200%, more than 500%) and in some implementations more than 1000%; and swelling after exposure to JRF (7 days) less than 20%.

Examples

The embodiments of the present invention are further illustrated by the following examples, which describe the synthesis, properties, and applications of some sulfur-containing prepolymers with Michael-acceptor end groups, thiol-terminated prepolymers and phosphine catalysts. It will be obvious to those skilled in the art that many modifications of both materials and methods can be made without departing from the scope of the present invention.

Example 1

Synthesis of polythioether prepolymer with thiol terminal groups

Triallyl cyanurate (6.0 pounds) and dimercaptodioxaoctane (DMDO) (169 pounds) are loaded into a 50 gallon reactor. The reactor is equipped with a stirrer, gas inlet and a thermometer. Start mixing. The reactor is rinsed with dry nitrogen. The reaction mixture is heated to 76 ° C. A solution of the radical initiator Vazo®-67 in diethylene glycol divinyl ether (126 pounds) is introduced into the reaction mixture for 2 hours while maintaining the temperature at 66-76 ° C. After adding divinyl ether, the temperature of the reaction mixture is raised to 84 ° C. The reaction mixture is cooled to 74 ° C and at intervals of 1 hour, nine portions of Vazo® 67 (a total of 0.2 pounds) are added while maintaining the temperature at 74-77 ° C. The reaction mixture is then heated at 100 ° C for 2 hours, cooled to 80 ° C and pumped out at 68-80 ° C / 5-7 mm Hg. within 1, 75 hours to obtain polymer with thiol end; in groups.

Example 2

Synthesis of prepolymer with vinyl sulfone end groups

A thiol-terminated prepolymer of Example 1 (3332.4 g), divinyl sulfone (260.53 g), toluene (417.08 g) and Polycat® 8 (1.80 g supplied by Air Products and Chemicals) are loaded into a five-liter round bottom flask equipped with a mechanical stirrer and a thermocouple. The mixture is stirred for 5 hours. The mixture is then heated to 95 ° C under vacuum to remove toluene and Polycat® 8 to obtain a polythioether prepolymer with vinyl sulfone end groups.

Example 3

Sealant recipe

The vinyl sulfone terminal polystyrene prepolymer of Example 2 (8.40 g), T-5314 (13.00 g, thiol end prepolymer supplied by PRC-DeSoto International, Inc., Sylmar, CA), and Cytop® 208 (0 , 0642 g, trihydroxypropylphosphine (supplied by Cytec) is loaded into a 60 gram plastic container. The mixture is stirred in a high-speed mixer for 60 seconds at 2300 rpm. The mixture is stored in a container. After four days, the mixture cures to 15 units of Shore hardness.

Comparative example 4

Sealant recipe

The prepolymer of example 2 (8.40 g) and T-5314 (13.00 g, thiol-terminated prepolymer supplied by PRC-DeSoto International, Inc., Sylmar, CA) are loaded into a 60 gram plastic container. The mixture is stirred in a high-speed mixer for 60 seconds at 2300 rpm. The mixture is stored in a container. After 10 days, the mixture remained pasty and uncured.

Example 5

Catalyzed Michael Attachment Curing Composition is prepared by combining polythioethers with thiol end groups (222.12 g, Permapol 3.1E, supplied by PRC-DeSoto International), HB-40 (5.29 g) and tung oil (2.84 g). 24.2 g of the polythioether composition are combined with 0.04% by weight. trioctylphosphine and then mixed with 0.80 g of vinyl sulfone. The sample of material is distributed and cured at room temperature. The hardness measured during curing is shown in FIG. one.

Finally, it should be noted that there are alternative ways to implement the implementations disclosed in the description. Accordingly, the present embodiments should be considered illustrative, and not restrictive. In addition, the claims should not be limited to the parameters specified in the application, and provides the right to the full extent of the claims and their equivalents.