Polyurethane-polysiloxane-polyoxyalkylene copolymers with reduced ing properties

92~ Mo-16 5 9 -E POLYURETHANE-POLYSILOXANE-POLYOXYALKYLENE COPOLYMERS HAVING REDUCED BURNING PROPERTIES Background of the Invention The instant invention relates to a process for the production of new, branched polysiloxane-polyoxyalkylene copolymers and to their use as stabilizers in the production of polyurethane plastics.

Polysiloxane-polyoxyalkylene copolymers (herein-after abbreviated to "PPC") are known and used as stabilizers and cell regulators in the production of foams made by the diisocyanate polyaddition process. Because of their particular chemical structure (i.e., strongly hydrophobic, generally `` branched polysiloxanes are chemically attached in a variety -~ of different ways to polyoxyalkylene ethers differing from ` 15 one another in their hydrophilicity), products of this type are able to reduce the surface tension of a foamable mixture to a relatively large extent. As a result, the cells in the process of formation are stabilized during the foaming reaction, so that the blowing gas which is formed during the reaction or which is already present in the mix ture develops its full effect and foams having a strictlyreproducible density are obtained. In addition, PPC's also , improve the homogeneity of the cell structure, and favorably influence the mechanical properties of the foams.

Accordingly, PPC's which are used in both rigid and flexible foams and in both polyester and polyether foams, are important constituents of any foaming formulation. Thus, because of the large number of variants in the foaming ,' ~ ~ LeA 16,777 ~ / .

~o~ process, an equally large number of PPC's are known and used. In spite of this, the generally known compounds to date are not able to solve every problem in the polyurethane foam area. Thus, in the production of foams from polyalkylene glycol ethers and simple polyisocyanates, such as tolylene diisocyanate, the use of PPC is equally as important as, for example, the use of tin catalysts because the foamable mixtures are of a very low viscosity and have to be stabilized if a pore structure is to be obtained.

According to more recent discoveries (see, e.g., German Offenlegungsschrift 2,129,922), the PPC's currently in use adversely affect the burning properties of the foams, i.e., the foams are inflammable. It can be shown that any reduction in the concentration of PPC is accompanied by an improve ment in burning properties and, thus, an optimum in burningproperties is obtained when no PPC at all is used. Since as mentioned above, polyalkylene glycol ether foam formulations based on the conventional isocyanates have to be stabilized, it is necessary in the absence of PPC to take specific measures,for example, through the use of modified polyisocyanates of higher functionality and viscosi~y (see, e.g., German Offenlegungsschrift 1,929,034 and 2,002,064).

;~ However, these particular measures make the foaming process ` relatively complex and uneconomical. Accordingly, there still exists the problem of finding PPC's which do not adversely affect the burning properties of polyether polyurethane foams, but which nevertheless show the required stabilizing and cell-regulating effect.

Surprisingly, this problem is solved by the polysiloxane-polyoxyalkylene copolymers made available by the ~ LeA 16,777 -2B~ ;

1~69'~ present invention.

Description of the Invention The present invention relates to a new, simple and hence highly economical process for the production of PPC's differing widely in their structure and showing a i ~ variety of different properties, and to the use thereof as stabilizers and cell regulators in the production of polyurethane foams.

The PPC's produced in accordance with the present invention have a high ~tabilizing capacity for polyether olyurethane foam mixtures and also improve the : flameproof properties thereof. .

The process of the instant invention broadly comprises reacting organopolysiloxanes corresponding to the general formula:

. _ z _ Z :- .

H-Y-R- - Si-O - _ Si-R-Y-H : .

z æ ~ ', . :

wherein m rapresents an integer of from 1 to 100, Z, which may be the same or different, represents a Cl-C5 alkyl radical, C6-C15 aryl radical, a siloxyl or a siloxanyl radical or the group -R-Y-H, R represent~ a Cl-C6 alkylene radical, optionally aontaining one or more hetero atoms, ï ~ "~' " ; O Y repreaent~ -NR'-, -O-, -C-O- or -S- and R' represents a hydrogen atom or a C1-C6 alkyl or C5-C~ cycloalkyl radical; .

LeA 16,777 -3_ :

. . - ':

' ' ' . . . ,; .

z~z with polyisocyanates in an equivalent ratio NCO:YH of _ 2.

The NCO-containing addition products thus obtained are heated at from about 110 to about 160C whereby they are branched.

The resulting relatively high molecular weight and branched NCO-containing addition products are then reacted with monofunctional polyethers corresponding to the general formula: .

R"~(CnH2n)x~H wherein n represents an integer of from 2 to 4, x represents an integer of from 1 to 100 and R" represents a monofunctional Cl-C20 hydrocarbon radical optionally containing oxygen or nitrogen as hetero atoms, in an NCO:OH ratio of from about 0.8 to about 1.2.

The present invention also relates to the use of .. . . .

the polysiloxanepolyoxyalkylene copolymers obtained by this process as foam stabilizers and cell regulators which improve the flameproof properties of the foams in which they are incorporated.

The polysiloxanes which may be used in accordance with the present invention are known and are described, for example, in German Auslegeschriften 1,114,632; 1,190,176 and 1,248,287.

These polysiloxanes contain at least two carbo- ~ functional groups which are attached to silicon and which contain isocyanate-reactive hydrogen atoms.

The carbofunc- .tional groups are preferably aliphatic Cl-C6 hydrocarbon radicals (optionally contalning hetero atoms), which contain at least one hydroxyl, carboxyl mercapto or primary or ; LeA 16,777 - -4- : :

.

~, -. :

l~69~æ secondary amino group.

The following are spec:ific examples of such carbofunctional radicals:

hydroxymethyl -CH20H hydroxybutyl -~CH2)40H ~-hydroxyethyloxymethyl . -CH2--0-CH2-CH2-oH ~-hydroxyethyl mercaptomethyl -CH2-S-CH2-CH2-OH ~,y-dihydroxypropyl mercaptomethyl ~ -CH2_S_cH2_cHoH-cH2oH . ,, ~ mercaptomethyl 15 -CH2SH ~-mercaptoethyl mercaptomethyl --CH2--S-CH2-CH2--SH ` ~-carboxyethyl -cH2-cH2-cooH aminomethyl . CH2 NH2 ` ~-aminobutyl .

`'~ --(CH2) 4-NH2 n-butylaminomethyl -CH2-NH-C4Hg ~nd .

cyclohexylaminomethyl CH2 NH C6N11 ' . , .

.

LeA 16,777 ~5~ ~ .

10~ The organopolysiloxanes may be obtained by known methods.

For example, the particularly suitable hydroxymethyl polysiloxanes may be obta:ined by directly reacting bromomethyl polysiloxanes with a:Lcoholic potassium hydroxide.

4-amino-butyl polysiloxanes may be obtained by hydrogenating the readily obtainable nitriles.

The corresponding carboxyl derivatives may be obtained by hydroly~ing the cyanoalkyl silicon compounds.

Aminomethyl siloxanes may be obtained by aminating the halogen methyl silicon compounds with ammonia or primary amines.

In many cases, the functional groups are first introduced into low molecular weight siloxanes. The thusobtained products are then converted into polysiloxanes of higher molecular weight by the known aquilibration reaction.

` 15 It is preferred to use polysiloxanes containing at least two and preferably from 6 to 30 siloxane groups and having molecular weights of from 194 to 20,000, preferably from 800 to 3000.

Other preferred polysiloxanes are substantially linear organofunctional polysiloxanes and those containing terminal hydroxy groups or amino groups~ , Suitable polyfunctional organopolysiloxanes are ` described, for example, in French Patent 1,291,937 and in ~ ;

German Auslegeschrift 1,114,632.

The fc~llowing are specific examples of organo functional polysiloxanes which are suitable for use in the process accordimg to the present invention:

Ho-cH2-si~cH3)2-olsi~cH3)2-o]12 Si(CH3)2 CH2OH LeA 16,777 -6 . . .

~l~)69ZL~ HO-CH-CH2-[si(cH3)2-o]ll-si(cH3)2 2 , 2 CH3 3 2 Si(CH3)2-O-si(cH3)2-cH2-oH 2 ( 3~2 [si(CH3)2-O]60-si(cH3)2-cH2-oH n-C4Hg-NH-cH2-si(cH3)2-o-[si(cH3)2 ]18 , ( 3 2 CH2 -NH-n-C 4H ., or 3 r . 3 1 / 3 ~ c6Hll-NH-cH2-si-o- si-o ~ l -si - O si (CH3)2 ... .

CH3 CH3 60 \ CH2-NH-C6Hll CH2-NH-C6H The organopolysiloxanes which are particularly preferred for use in accordance with the present invention correspond to the general ~ormula:

I10-Cli2-~ 0-~ C112-0~ CH3 CH J m = 6 to 30 They may be obtained in known manner by reacting 1,1,3,3 : tetramethyl-1,3-hydroxymethyl disiloxane corresponding to the formula~ ,, .:

CH3 CH3 HO-H2C-Si-O-Si-cH2-OH : "'' :

with octamethyl cyclotetrasiloxane in the presence of sul- :

phuric acid or by~the process according to German Auslegeqchrift 1,236,505.

~ : ', ' ',' ' LeA 16,777 -7- . : ~ 9242 According to the present invention, the carbofunctional oryanopolysiloxanes are reacted with polyisocyanates in an equivalent ratio between NC0-groups and isocyanatereactive hydrogen atoms of at least 2, and pre~erably of 5 from 2 to ~ and, most preferably,, of from 2.2 ~o 3.

Isocyanates suitable for use in accordance with the present invention include any aliphatic, cycloaliphatic, araliphatic and aromatic polyisocyanates of the type generally known and described, for example, by W.

Siefken in Justus Liebigs Annalen der Chemie 562, pages 75 to 136.

Specific examples include ethylene diisocyanate; 1,4tetramethylene diisocyanate; l,~-hexamethylene diisocyanate;

1,12-dodecane diisocyanate; cyclobutane-1,3-diisocyanate;

cyclohexane-1,3- and -1,4-diisocyanate and mixtures of the isomers; 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl cyclohexane (German Auslegeschrift 1,202,785); 2,4- and : 2,6-hexahydrotolylene diisocyanate and mixtures of the isomers; hexahydro-1,3- and/or -1,4-phenylene diisocyanate;

perhydro-2,4'- and/or -4,4'-diphenyl methane diisocyanate; : ` 1,3- and 1,4-phenylene diisocyanate; 2,4- and 2,6-tolylene ~;

diisocyanate and mixtures of the isomers; diphenyl methane- ` ` :

2,4'- and/or -4~4'-diisocyanate; naphthylene-1,5diisocyanate; txiphenyl methane-4,4',4"-triisocyanate; poly- ..

phenyl-polymethylene-polyisocyanates of the type obtained by condensing aniline with formaldehyde, followed by ph~osgenation, and de~3cribed for example in British Patents :

874,430 and 848,671; and the like. ::

. . ..

As a rule, it is pre~erred to use readily available polyisocyanates such as 2,4- and 2,6-tolylene diiso- :

cyanate and mixtures of the isomers ("TDI"); polyphenylLeA 16,777 : -8- . 242 polymethylene-polyisocyanates of the type obtained by condensing aniline with formaldehyde, followed by phosgenation ~MDI); 1,6-hexamethylene diisocyanate (HDI); and 1isocyanato-3,3,5-trimethyl-5-isocyanatomethyl cyclohexane (IPDI~.

In general, the foam stabilizers according to the present invention are produced by initially introducing the polyisocyanates and subsequently adding the organopolysiloxanes.

However, it is, of course, possible initially to introduce the organopolysiloxanes and then to add the polyisocyanates to the reaction mixture.

According to the present invention, organo metallic compounds, more especially organo tin compounds, may be used as catalysts for acce~erating the reaction.

Preferred organo tin compounds are tin(II)salts of carboxylic acids, such as tin(II)acetate, tin(II)octoate, tin(II)ethyl hexoate and tin(II)laurate, and dialkyl tin salts of carboxylic acids, such as dibutyl tin diacetate, dibutyl tin dilaurate, dibutyl tin maleate or dioctyl tin diacetate. ;~ Further representatives of catalysts suitable for use in accordanc:e with the present invention and information on the way in which the catalysts function may be found in Vieweg and Hochtlen's Kunststoff Hanc~uch, Vol. `~ VII, Carl-Hanser-Verlag, Munich 1966, pages 96 to 102.

The catalysts are generally used in a quantity of from about O.OOl to 10%, by weight, based on the total weight of the reaction mixture.

LeA 16,777 _9_ ~: . , , ~0~9;~42 According to the present invention, it is also possible to use reaction retarders, for example, acidreacting compounds, such as hydrochloric acid or organic acid halides.

According to the present invention, it is necessary, especially in cases where the organopolysiloxanes used still contain alkalis or weakly alkaline reacting substances from their production, to add acid-reacting substances, such as hydrochloric acid, sulphuric acid, ptoluene sulphonic acid, _-toluene sulphonic acid methyl ester or benzoyl chloride, in quantities of from 0.1 to 2%, by weight, preferably from 0.05 to 0.1%, b~y weight, based on the quantity of the siloxane compound, to the reaction mixtures before the reaction with the polyisocyanates.

After the first stage of the reaction in the process according to the present invention, the NCO-containing ;

addition products are heated whereby branched products are obtained.

In this heat treatment, the mixtures are generally heated over a period of from 4 to 20 hours, preferably from 6 to 10 hours, at a temperature of from about 110 to 160C and preferably at a temperature of from 140 to 150C.

Water je~ vacuu~ ifi then pre~erably applied at approximately 1503C until a vacuum of about 14 Torr is reached.

Volatile constituents, consisting predominantly of octamethyl cyclotetrasiloxane and excess polyisocyanate, distill o~f in thiS vacuum.

.;

The ~heat treatment of the reaction products of organopolysiloxanes and polyisocyanates which is carried out in the process according to the present invention results in the development of branchings through allophaLeA 16,777 -10 , ' .~ .:

nate, biuret and/or isocyanurate groups.

Thereafter, the products have an average functionality (number of free NCOgroups) of preferably from about 3 to 4.

In a third stage, the relatively high molecular weight, branched NCO-containing addition products obtained in the second stage are reacted with monofunctional polyethers corresponding to the following general formula:

' ':

R''-(OCnH2n)X-oH wherein .

n represents an integer of from 2 to 4, x represents an integer of from 1 to 100, preferably from 15 to 50, and R" represents a monofunctional Cl-C20, preferably C4-C~2, hydrocarbon radical optionally containing oxygen or nitrogen as hetero atoms;

.. . .. .

in an NCO:OH ratio of from 0.8 to 1.2, preferably in an NCO:OH ratio of about 1, at a temperature of from about 30 to 150C and, preferably, at a temperature of from 100 to 130~C.

According to the present invention, catalyst3, e9pecially organometallic compounds and, with par~icular preference organotin compounds, may also be added during this stage-of the reaction.

According to the present invention, it :is of advantage particularly in cases where no catalysts were used in the first stage of the reaction, i.e. during reaction of the polysiloxanes with the diisocyanates, to catalyze this third stage of the reaction with organotin compounds.

LeA 16,777 9~42 According to the present invention, it is particularly preferred to use monofunctional polyethers which have been produced by the polymerization of a mixture of ethylene oxide and propylene oxide (molar ratio 1:9 to 9:1) on alkanols, preferably butanol, as starter.

Preferred organotin compounds are again tin(II) salts of carboxylic acids, such as tin(II)acetate, tin(II) octoate, tin(II)ethyl hexoate and tin(II)laurate, and also - the dialkyl tin salts of carboxylic acids, such as dibutyl tin diacetate, dibutyl tin dilaurate, dibutyl tin maleate or dioctyl tin diacetate.

The catalysts are again generally added in a quantity of from about 0.001 to 10%, by weight, based on the mixture as a whole.

' After the catalyst has been added, a gentle exothermic reaction is observed, the previously hazy mixture of the reaction components becomes transparent.

In order to complete the reaction, the reaction mixture is maintained at approximately lQ0C for about another hour.

.

After cooling, foam stabilizers having viscosities at 25C of, in general, from 2000 to 80,000 cP are obtained, depending upon the type of starting components used.

.::~, The relatively high viscosity of the stabilizers produced in acc:ordance with the present invention is often a disadvantage for machine processing into foam formulations.

Accordingly, th~e end products of the process according to the pre3ent inYention are preferably used in solution in solvent~ which do not affect the activi~y of the stabilizer.

LeA 16,777 -12 . ~.

. .

ii92~2 Generally, it is preferred to use water-soluble diluents.

Polyethers having terminal primary OH-groups corresponding to the following general formula are particularly suitable:

R [ ~Cn'2nJx ] k .

5wherein n represents an integer of from 2 to 4, x represents an integer of from 1 to 100, preferably from 15 to 50, ~"' represents a k-functional hydrocarbon having from 2 to 1020 carbon atoms, and . ( .

k represents an integer of from 2 to 8. ~ ~ , .. .

By mixing the stabilizers with polyethers of this ~.

type in a quantitative ratio of from 2:1 to 1:4, and prefer- ~.

ably fro~ 1:1 to 1:2, stabilizer solutions are obtained :

having viscosities of from approximately 1000 to 3000 cP/ 25~C. ..

: It is extremely surprising that these mixtures ~: - of the foam stabilizers according to the present invention : with polyethers are almost as active in their stabilizing and cell-regulating properties as an equivalent quantity of the pure end product of the process according to the present invention (cf.

Examples 2 and 3).

.

. ~he polyether diluents suitable according to the instant invention, generally contain from 2 to 8 and prefer~ ably 2 or 3 hydroxyl groups are generally known and may be obtained, for example, by the polymerization of epoxide~ - LeA 16,777 -13- :

~ - '.:, ~.

.:: ..

2~2 such as ethylene oxide, propylene oxide, butylene oxide, ~tetrahydrofuran, styrene oxide or epichlorohydrin, on their own, for example, in the presence of BF3, or by the addition of these epoxides, optionally in admixture or successively, with starter components containing reactive hydro- gen atoms, such as water, alcohols or amines, such as ethylene glycol, 1,3- or 1,2-propylene glycol, 1,4-butane diol, trimethylol propane, 4,4'-dihydroxy diphenyl propane, aniline, ammonia, ethanolamine or ethylene diamine.

It is also possible in accordance with the present invention to use sucrose polyethers of the type described, for example, in German Auslegeschriften 1,176,358 and 1,064,938.

In many cases, it is preferred to use polyethers of the type which contain predominant amounts of primary OH-groups (up to 90%, by weight, based on all the OH-groups present in the polyether).

Polyethers modified by vinyl polymers, of the type obtained, for example, by polymerizing styrene and acrylonitrile in the presence of polyethers (U.S.

Patents 3,383,351; 3,304,273; 3,523,093; 3,110,695; German Patent 1,152,536) are also suitable, as are polybutadienes con-taining OH-groups.

:, .

It i~, of course, preferred to use liquid polyhydroxyl compounds of extremely low viscosity as solvent.s for the products obtained by the process according to the present inventiLon. ~ The production of foams using the stabilizers according to the present invention is carried out in known manner by react:ing polyisocyanates (for example of the type described above) with compounds containing two or more ~' isocyanate-reac~tive hydrogen atoms (generally polyethers or ~ LeA 16,777 -14- ~ , :, . ~ .~..

.'h polyesters having from 2 to 8 hydroxyl groups and a molecular weight of from 500 to 10,000) in the presence of blowing agents and, optionally, catalysts (cf. for example, Vieweg and Hochtlen's Kunststoff-Handbuch, Vol. VII, Carl-HanserVerlag, Munich, 1966; Saunders-Frisch: Polyurethanes, Chemistry and Technology, Interscience P~blishers, New YorkLondon, 1962).

The foam stabilizers are generally added to the foamable mixture in a quantity of from 0.4 to 2.0~, by weight, and preferably in a quantity of from 0.5 to 1.5~, by weight based on the total weight of the foamable reaction mixture.

The ~,~'-bis-(hydroxymethyl)-polydimethyl siloxanes used in the Examples were produced in accordance with German Auslegeschrift 1,236,505.

The following are specific, nonlimiting examples which are provided to illustrate the enumerated principles described herein.

All parts are by weight unless otherwise lndicated.

.

'. ~' ; , LeA 16,777 -15 :

- :: ......... ~ - . .. . .

~9'~4;2 EXAMPLE 1(a) Production of stabilizer 50 g of ~-toluene sulphonic acid methyl ester are added at room temperature to 77.88 kg of ~,~'-bis-(hydroxymethyl)-polydimethyl siloxane (OH number 78). I'he mixture is then heated under nitrogen to 70C. 22.12 kg of a mixture of 2,4- and 2,6-tolylene diisocyanate (80:20) are then added to the mixture at that temperature.

Under the effect of the exothermic reaction which begins immediately, the contents of the vessel undergo an increase in temperature to from 100 to 110C.

The mixture is then heated to 150C and maintained at that temperature for 6 hours.

Water jet -;

vacuum is then applied until, finally, a vacuum of 14 Torr is reached. 756 g of volatile constituents, consisting predominantly of octamethyl cyclotetrasiloxane, distill off.

After the heat treatment and vacuum treatment the prepol~ner has an NCO-content of 4.55%.

The contents of the vessel are left to cool to 130C. 282 kg of a polyether is added.

The polyether is based on propylene oxide and ethylene oxide in a mixing ratio of 50:50 ~O~ number 21.5), and is started on n; butanol in the presence of catalytic quantities of sodium :...., : ~ alcoholate.

Aft:er homogenization of the components 0.05% of tin(II)ethyl hexoate is added based on the mixture as a whole.

After the catalyst has been added, a gentle exothermic reaction i9 observed and the previously hazy mixture of the comp~onents becomes clear.

To complete the reaction, the mixture 18 maintained at 100C for a perlod ; - of one hour.

The ~tabilizer then formed ha~ a viscosity of LeA I6,777 -16 ' ', - ' ' . .

~o~ 41,800 cP/25C and a refractive index n20 of 1.4615.

EXAMPLE l(b) Production of a machine-processible stabilizer solution:

The high viscosity of the stabilizer produced in accordance with Example l(a) is reduced simply by mixing the stabilizer with a 1,3-propylene glycol-started polyether, in which propylene oxide and ethylene oxide in a mixing ratio of 50:50 have been polyadded in the presence of catalytic quantities of sodium alcoholate (OH number 56).

Mixing is carried out in a mixing ratio ~y wei~ht Qf~lizer to "solvent polyether" of 1:2.

The solution has a viscosity of 1780 cP/25C and is eminently suitable for machine processing.

.

EXAMPLE 2~a) Production of a polyurethane-polyurea foam using the stabilizer according to Example l(a):

100 parts, by weight, of the polyether described below are thoroughly mixed with 0.2 part, by weight, of triethylene diamine and 0.25 part, by weight, of the tin(II) salt of 2-ethyl caproic acid. 1.2 parts, by weight, of the ~ stabilizer and 4 parts, by weight of water are then added.

50 parts, by we~ight, of tolylene diisocyanate (80% of 2,4and 20~ of 2,6-isomer) are then added to thi~ mixture, followed by thorough mixing with a high-speed stirrer.

After a cream time of' 10 seconds, foam formation begins and a white, flexible~, elastic open- and fine-pored polyurethanepolyurea foam i~ formed.

LeA 16,777 -17 .

~o~ z The polyether used for producing the polyurethanepolyurea foam was produced as fo:Llows:

Propylene oxide was first subjected to polyaddition onto a mixture of trimethylol propane and propylene glycol in the presence of catalytic quantities of sodium alcoholate.

Ethylene oxide was polyadded in a second stage.

The liquid polyether contains primary and secondary hydroxyl groups and has an OH number of 49, an average molecular weight of 3200 and an average functionality of 2.78.

EXAMPLE 2(b) Production of a polyurethane-polyurea foam using the stabilizer solution according to Example l(b):

100 parts, by weight, of the polyether (OH number 49) used in Example 2(a) are thoroughly mixed with 0.2 part, by weight, of triethylene diamine, 0.25 part, by weight, of the tin(II)salt of 2-ethyl caproic acid, 1.2 parts, by weight, of the ~tabilizer solution and 4 parts, by weight, of water. 50 parts, by weight, of tolylene diisocyanate (80~ of 2,4- and 20~ of 2,6-isomer) are ~tirred into thi9 mixture~uJing a high-9peed stirrer.

After a ~; cream time of 10 seconds, foam formation begins and a white, ~ . .

flexible, elastic, open- and fine-pored polyurethanepolyurea foam is formed in the same way as in Example 2(a).

EXAMPLE 3 Production of a Iself-extinguishing polyurethane-polyurea foam using the stab1lizer solution described in Example l(b):

100 pa~ets by weight of the polyether described in LeA 16,777 -18 ' .

.

Z~2 Example 2(a), 3.0 parts by weight of water, 0.10 part by weight of ethyl diethanolamine, C).22 part by weight of tin octoate and 5 parts by weight of tris-(2,3-dibromopropyl)phosphate as flameproofing agent are thoroughly mixed. 0.6 part by weight of stabilizer (three different foams were produced with three different stabilizers) are added to the resulting mixture, followed by the introduction of 40.7 parts by weight of tolylene diisocyanate (80% of 2,4- and 20% of 2,6-isomer).

The mixture was then thoroughly stirred using a high-speed stirrer.

Foams having the characteristics described below are obtained, depending upon ` the particular stabilizer used.

LeA 16,777 -19- - .

.

- . ~.

~)6~4~ : Commercial Stabilizer Commercial polyether- of Example polyetherpolysiloxane l(b) polysiloxane stabilizer flame proof(B 2730* of ing stabili Goldschmidt zer (B3640* : AG Essen, Goldschmidt Germany~ AG Essen, Germany) __ _ Rise time [sec.] 140 131 138 ._ Gel time [sec.] 53 46 39 _ _ . _ . .

Density 3 (DIN 53420)[kg/m ) 37 32 34 _ ~ : 15 Tensile strength (DIN 53571)[KPa] 90 110 100 Elongation at break (DIN 53571)[%] 140 270 230 _ _ Compression hardness at 40% (DIN 53577)[KPa]5.00 3.34/3.43 3.. 63 ._. ._ Compression set at 90%.4.1 3.7 3.6 `~ .. . _ ..

.. .... __ Flameproof testing in accordance. with ASTM D 1692 - 68 .

Average charred length . 64 48 47 .__ ~, : Average extinguishing .

time 51 34 39 .'.~ .. . __ .. _ Average burning rate _ _ : . .. _ Assessment SE SE SE .

After 22 hours ageing in hot air (140C): .

. . .

~ Average charrecl length: (115) 46 ._ .. _ 30 Average extinguishing .

. time 106 27 ~ ~ ._ : .

~ *Trademarks ..

LeA 16,777 -20''E~ .

... . . .

242 Standard Stabilizer Standard Commercial- of Example Commercialgrade sta- l(b) grade flame bilizer proofing (OS 20*; stabilizer Bayer) (B3640*;

: Goldschmidt AG Essen) _ Average burning rate 76 _ 94 _ 10 Assessment Br. . SE Br , After 5 days ageing at 90C/95% relative humidity ., Average charred length _ 47 Average extinguishing ~ time _ 27 :. 15 Average burning rate. 59 _ 87 Assessment Br SE Br After 5 hours ageing at 120C in a steam autoclave:

.

. j . _._ I Average.charred length 72 . 3.8 40 Average extinguishing ~` 20 time ................... . 6.8. . . .. . 2.8. . . 3.3 . .

, Average burning rate ... ......... .. ........ . . .... ......

Assessment - SE SE SE ...... ... .. -.... .... -... ... -.................. ... ....... ..........

. ...................... ..... ....

, : :

SE = self-extinguishing Br = burning *Trademarks ., .

1 .

. .

' LeA 16,777 -21 i. ..... . . . ., .. , . ., ~ . ...... .

~C~69~4~ EXA~LE 4 50 g of ~-toluene sulphonic acid methyl ester are added under nitrogen at room temperature to 69.4 kg of the organopolysiloxane of Example 1, followed by the addition at 70C of 30.6 kg of 4,4'-diisocyanatodiphenyl methane.

Under the effect of the exothermic reaction which begins immediately, the contents of the vessel undergo an increase ~ in temperature to from approximately 100 to 110C.

The - mixture is then heated to 150C and maintained at that temperature for 7.5 hours. A water jet vacuum is then applied until finally a vacuum of 14 Torr is reached.

Approx- ;

imately 620 g volatile constituents, consisting predominantly of octamethyl cyclotetrasiloxane, distill off.

The prepolymer formed has an NCO-content of 5.04~.

The contents of the vessel are left to cool to from 120 to 130C, followed -~ by the addition of 311 kg of the n-butanol-started poly- ether of Example 1 and then, after homogenization of the components, by the addition of 0.05 % of tintII)ethyl hexo- :

ate, based on thé mixture as a whole.

After the activator has been added, a gentle èxothermic reaction is observed ;

and the previously hazy mixture o~ the components becomes clear.

In order to complete the reaction, the mixture is maintained at 100C for 1 hour.

Thereafter, the stabilizer has a viscosity of 41,900 cP/25C.

After the stabilizer has been mixed~with the polyether described in Example l(b) in a mixing ratio of 1:2, a stabilizer solution having a viscosity of 1750 cP/75C is obtained.

., .

; EXAMPLES 5 - 14 ,- General Procedure:

LeA 16,777 -22 ~0692~;~ 0.05~ of p-toluene sulphonic acid methyl ester tbased on the total quantity~ are added at room temperature to 100 g of ~ bis-(hydroxymethyl)-polydimethyl siloxane, followed by the introduction at 70C of the specified quantity of polyisocyanate (NCO:OH-ratio >2).

The mixture is then heated to the temperature indicated and left at that temperature for 5 and 6 hours. A water jet vacuum ~ is then applied until finally a vacuum of 14 Torr is reached.

After vacuum treatment for 1 hour, the NCO-number of the prepolymer is determined.

The mixture is left to cool to 130C, followed by addition of the specified quantity of the monofunctional polyether (NCO:OH-ratio = 1) and then, after homogenization of the components, by the addition of 0.05% of tin(II) ethyl hexoate, based on the mixture as a whole.

In order to complete the reaction, the mixture is maintained at 100C for 1 hour.

The final stabilizers have the viscosities indicated.

The monofunctional polyether used was obtained by the polyaddition of alkylene oxide/propylene oxide in a mixing ratio of 1:1 onto n-butanol.

., .~ .

~- ' .

: . ;' .

.

,~ :

~ ..

LeA 16,777 -?3 .. . . .

., .

- ~06i~ N ~1 U O O O O O O O O O O :

O ~P O O O O O ~ O O~ R 8 ~ ~ 1~ ~ u~ ~ ~ ~ ~ ~ ~ ~ D~ ~ O ~r u~ ~D ~ ~ O~ a~ ~r u~ ~ C~ _I ~1 N ~ ~ _~0 ~olo~ _ ____ _ ~S~ ~ Lr~ In ~ . .. , :: `, ' 0 C) ~ a~ ~1 oo ,_1 ~ ~ ~7 ~D ~ 0 o ~ o ~a o ~ cr~ ~ er ~ O~ ~ Ln ~D S~ Ul O ~ ~ ~ _1 ~1 ~ ~ ~ ~ ~1 ~1 U~ Sl~a) ~ _ Q) ~' C~ OD ~0 ~r co ~ er 1~ ~r ~ ~ . ~ ~1 ~ _1 ~i r~i ~i 00 ,_i ~ O ~1 ~ ~ N t`~ ~`I ~1 : :, O~oC) '~''' Ul 1~ ~ 1/~ O O O O O I` O ~ O~ ~ ~D U~ U~ U7 _1 U~ I~ ~P : .

O ~ ~ ~1 ~ ~ t` 1~ CO 1~ el~ l' ,0 ~ ___ ~ t~ 11~ ~' ' I ~ C.) 00 CO r~ t` N ~ ~) ~ cr~ CO O ~ ~Z 0~ ~ ~O CC~ I~ I~ O tl~ ~ O Z~ P ~ ~r ~ ~ ~ ~ r~ ~r t~l ~1 .. _ . _ __ : .: .

~O I O IS~ U~ Il') ~) U~ IS~ ~D 11) ~D ~O , ~`, ' ....

.. _ _ . _ . . .

~ ~ O O O O O O O O O O . , .

O C~ 1~ Lf) U') 11~ Il') Il') 11~ Lt~ 11~ 11~ __ ___ _l -1 -1.............. ~ _ -1. ", ,.-.. - .

u~ o a) cO co 1~ c~ OD CO OC~ CO CO Ct~ .` ~ ~ I~ ~ t~ r~ I~ ~ I~ ~ _l ~ .

,` ~ ~ ~ _ _ . _ ,' ~ 0 ~ o 1~ ~ ~ ~n Il~ _l ~D ~ t~l X .,1 --~ o~ u~ ~ ~ ~D ~9 ~r x ~ N ~ ~--' t~l N ~1 ~1 ~ ~ ~r N _I 1~ ~ .

., . ,_.___ ..... . __ _ _ I~ ~ ~ .~.

rl ~ ~ ~3 ~ H H H ~! ~ H H .;

Q~ _ . . _ _ ___ ~ ' X Z 11~ ~ ~ OD Cl~ O _I N LeA 16, 777 -24.. ...

' . . ".

: , .~ . , . -. . . - - . , . , . - . . . z~z ~:

EXAMPLE 15 1.6 g of p-toluene sulphonic acid methyl ester are added at room temperature to 2460 g of ~,~'-bis-(hydroxymethyl)-polydimethyl siloxane (OH-number 78), followed by the introduction under nitrogen at 70C of 700 g of tolylene diisocyanate (80 ~ of 2,4- and 20% of 2,6-isomer).

Under the effect of the exothermic reaction which begins immediately, the mixture undergoes an increase in temperature to form 100 to 110C.

The mixture is then heated to 150C and maintained at that temperature for 6 hours. A vacuum is then applied until finally a vacuum of 14 Torr is reached.

50 g of octamethyl cyclotetrasiloxane and excess tolylene diisocyanate distill off.

Therea~ter, the prepolymer has an NCO-content of 4.4~ and a viscosity of 3140 cP/25C. 3100 g of the siloxane prepolymer obtained in this way are then mixed with 9000 g of a butanol-started polyether (OH-number 18.B) in which ethylene oxide/propylene oxide in a mixing ratio of 70:30 were initially polyadded in the presence of catalytic quantities of sodium alcoholate, followed in a second stage by the polyaddition of ethylene oxide, the re!3ulting mixture heated from 90 to 100C and 10 ml of tin (II)octoate added. ~o complete the reaction, the mixture is stirred unlder nitrogen for 1 hour at from 90 to 100C.

The NCO-~ree stabilizer has a viscosity of 75,000 cPj2SoC.

' The high viscosi~y of the stabilizer is reduced .

by mixing with the polyether described in Example l(b) and by the proces!3 described in Example l(b) in a mixing ratio o~ 1:2 between stabilizer and "solvent polyethern. ~he solution then has a viscosity of 1800 cP/25C.

- ~ LeA 16,777 -25 , , : . :.:

2~Z EXAMPLE 16 Production of a polyester-polyurethane foam:

100 parts, by weight, of a polyester having an OH- number of 60 and an acid number of at most 1.5, produced from adipic acid, diethylene glycol and trimethylol propane, 3 parts, by weight, of water, 1.0 parts, by weight, of ethyl :

diethanolamine, 40 parts, by weight, of tolylene diisocyanate ~ (80~ of 2,4- and 20% of 2,6-isomer) and 1.5 parts, by weight, :

: of the foam stabilizer of Example 15 are thoroughly mixed using a high-speed stirrer.

Foams having the following . .

characteristics are obtained:

density (kg/m3) 38 : tensile strength (KPa) 160 elongation at break (%) 140 compression hardness at 40% (~Pa) 7.0 compression set at 50% 3.8 EXAMPLE 17 .` .

Production of a hydrophilic polyether polyurethane foam:

100 parts, by weight, of a glycerol-started poly~ 20 ether, in which propylene oxide was first polyadded in the - presence o catalytic quantities of sodium alcoholate, fol~ .~ lowed in a second stage by the polyaddition of ethylene . oxide ~OH-num~er 26; average functionality 3; average molecu- . . .:

. . .

lar weight 6500), 3 parts by weight, of water, 0.25 part, . ~ 25 by weight, o~ dlmethyl benzyl~mine, 0.4 part by weight of ~ - .

tin(II)octoate, 35.6 parts, by weight, of tolylene diisocya- .. - nate ~65% of 2,4- and 35% of 2,6-isomer) and 0.8 part, by weight, of the foam stabilizer of Example 15 are thoroughly : . .

LeA 16,777 -26- :~ .

, : : . :.

....

.. . . .

~0gj9242 mixed using a high-speed stirrer. ~ foam having the following characteristics is obtained:

density (kg/m3) 32 tensile strength tKPa) 98 elongation at break (%) 390 compression hardness at 40% (KPa) 5.0 compression set at 90% 8.20 tensile strength, wet (KPa) 58.9 elongation at break, wet (%) 175 , ": ' LeA 16,777 -27~