Process for the production of acrylic resins and their use.

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

0001This invention relates generally to a composition of acrylic resins for coatings, adhesives, etc. and to a process for synthesis of the resins.

DESCRIPTION OF THE PRIOR ART

0002A large variety of acrylic coating compositions are known. Low solids coatings, i.e., those containing about 18 to 40 wt% solids and the balance solvents, have heretofore been developed in which the resins themselves are characterized by high molecular weights, e.g., molecular weights in the range of 20,000 to 40,000. Such high solvent concen­trations are required with these high molecular weight resins in order to supply flowability and other properties necessary for ease in applying a uniform coating. Due to strict air pollution regulations, pollution abatement of solvents is of paramount importance. To this end, the industry has expended much effort in an attempt to develop electrostatically sprayable coatings containing high solids contents; that is, coatings having a lower amount of solvents in order to satisfy pollution regulations. Attempts to achieve high solids coatings by merely using more of the conventional high molecular weight resins in the coatings have not been successful since the increased solids content using these resins results in an un­acceptably high viscosity, and often the larger amounts of the resins cannot themselves be dissolved.

0003Efforts at developing a "super solvent" for these conventional high molecular weight resins have also not proved to be successful. One prior art approach has been to formulate coatings containing low mole­cular weight resins (e.g., of about 1,000 to 7,000 weight average molecular weight) would be desirable in high solids coatings in order to reduce the amount of solvents necessary in the blending for coating appli­cations and, hence, the pollution difficulties associated with the solvents themselves. After appli­cation of the coatings to a surface, the coatings are cured to form a polymeric network of higher molecular weight and enhanced physical properties. These high solids acrylic coatings are useful as exterior finish for automobiles, trucks, metal furniture, and as an appliance finish.

0004K. K. Mitra, "Electrostatic Application of Paint", <u style="single">Paint India</u>, vol. 29, no. 9, pp. 52-56 (1979) indicates that while non-polar solvents (aliphatic and aromatic hydrocarbons chlorinated solvents, terpenes, etc.) can be employed in electrostatically sprayable paints to increase bulk and resistivity, polar sol­vents are used to control resistivity. The polar group is said to include ketones, alcohols, esters, ethers, ether alcohols, and nitro paraffins, etc. The non-polar group is said to include aliphatic and aromatic hydrocarbons, chlorinated solvents, terpenes, etc.

0005Also illustrative of prior art, high solids acrylic resins are those disclosed in U.S. Patent 4,276,212 and in European Patent Applications 27,719; 29,594 and 29,683.

0006Solvents which are indicated to be typical in these references (e.g., those mentioned in European Patent Application 29,594) are: Toluene, xylene, butyl acetate, acetone, methyl isobutyl ketone, methyl amyl ketone, methyl ethyl ketone, butyl alcohol and other aliphatic, cycloaliphatic and aromatic hydrocarbons, esters, ethers, ketones, and alcohols.

0007In a brochure entitled "Hexyl Acetate for the Coatings Industry" (Enjay Chemical Company), published prior to 1980, use of hexyl acetate as coating solvent in certain specific low solids acrylic coating compositions; in urethane coatings; in nitro-­cellulose coatings; and in baking enamels was disclosed.

0008U.S. Patents 4,075,242 and 4,276,432 disclose the preparation of acrylic-based resins by use of polymerization media containing certain high boiling solvents and disclose the use of ethylene and propylene as co-monomers.

0009European Patent 29,339 discloses the formation of bifunctional copolymers in which the monomers comprise from 5 to 25 wt% of monoethyleni­cally unsaturated monomers having a glycidyl func­tionality, from 5 to 25% of monoethylenically unsaturated monomers having hydroxy functionality and 90 to 70 wt% of other monoethylenically unsaturated monomers, with acrylates as well as mixtures of acrylates and vinyl hydrocarbons being preferred. Only monovinyl aromatic hydrocarbons are particularly indicated as useful (e.g., styrene, alpha-methyl styrene, vinyl toluene, t-butyl styrene and chloro­styrene).

0010U.S. Patent 4,369,296 relates to the production of methyl methacrylate homopolymers (or copolymers with certain copolymerizable vinyl monomers; e.g., styrene and alkyl-substituted styrene) in the presence of from 0.01 to 10 wt% of enol ethers derived from aliphatic or cycloaliphatic aldehydes and ketones.

0011U.S. Patent 3,271,375 relates to the use, in combination with a free radical polymerizable materi­al, of certain unsaturated heterocyclic organic compounds as molecular weight regulators. The prior art has sought to control the degree of polymerization via chain transfer content (in the preparation of acrylic oligomers for high solids coating resins) by use of relatively inactive solvents such as alkyl aromatics, high boiling ethers and benzyl alcohol. D. Rhum, et al., <u style="single">J. Coatings Tech'n.</u> Vol. 55, no. 703, 75-79 (August 1983).

0012U.S. Patent 4,532,294 relates to the preparation of acrylic copolymer resins employing polymerization solvents comprising certain alkanoic acid alkyl esters for copolymerization of hydroxy-­substituted alkyl (meth)acrylate and non-hydroxy substituted alkyl (meth)acrylate monomers, and in optional presence of additional monomers comprising monovinyl aromatic hydrocarbons. Among the non-­hydroxy substituted alkyl (meth)acrylate monomers which may be employed are (meth)acrylates as well as mixtures of acrylates and vinyl hydrocarbons.

0013U.S. Patent 3,926,925 relates to novel interpolymers containing an olefin (an alpha-olefin, a 2-alkyl-1-olefin and a vinyl aromatic) polar monomers, such as an alkyl acrylate, and a fumarate ester or a maleic acid derivative which are prepared with a catalyst system of an alkyl aluminum halide and an organic peroxide. U.S. Patent 3,959,225 relates to a thermally-staged process for preparing alternating interpolymers of one or more polar monomers and one or more mono or polyolefins in which a polar monomer-­Lewis Acid complex is reacted with an olefin in the presence of an active oxygen compound. The olefins disclosed as useful in U.S. Patent 3,959,225 are certain Type I olefins and Type III olefins.

0014U.S. Patent 3,968,148 relates to oligomers of (i) about 10 to 90 wt% of 1-alkene; (ii) about 1 to 45 wt% of a straight or branched chain alkyl acrylate or (meth)acrylate in which the alkyl group contains 8 to 34 carbon atoms; and (iii) 1 to about 35 wt% of an acrylic acid, ester or nitrile, or a mixture of such acids, esters, nitriles, and amido and amino deriva­tives.

SUMMARY OF THE INVENTION

0015According to one aspect of the present invention, improved low molecular weight acrylic copolymer resins capable of cross-linking are provided by free-radical co-polymerization of a mixture of (i) at least one member selected from the group consisting of (meth)acrylic acid and hydroxy-substituted alkyl (meth)acrylates, (ii) at least one non-hydroxy substituted monomer selected from the group consisting of vinyl aromatic hydrocarbons and lower alkyl esters of methacrylic acid, and (iii) at least one alpha­olefin having from 7 to 20 carbon atoms per molecule. These low molecular weight acrylic resins are parti­cularly useful as components in adhesives and in high solids acrylic coatings suitable for electrostatic spraying.

0016Low molecular weight acrylic copolymers find extensive application in coatings, adhesives, etc. The polymers are synthesized by free-radical co-­polymerization of monomers selected from the group comprising esters of acrylic and (meth)acrylic acids, styrene and its homologues, monomers bearing func­tional groups such as hydroxylalkyl acrylates and (meth)acrylates, acrylic and (meth)acrylic acids, glycidyl acrylate and (meth)acrylate, etc. in organic solvents.

0017We have found that all or at least a significant proportion of the alkyl acrylates, such as ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate, which are used in coating resins to regulate Tg and impart flexibility to the coating films, can be substituted by C₇-C₂₀ alpha-olefins. This substitu­tion can result in a reduction of molecular weight, improvement in color of the polymer solutions, and also potential improvement in the polymer's hydrpho­bocity, along with other important polymer properties.

DETAILED DESCRIPTION OF THE INVENTION

0018The oligomers of this invention will comprise: (i) from about 5 to 45 wt% and preferably from about 10 to 35 wt%, at least one of the group consisting of (meth)acrylic acid and hydroxy-­substituted alkyl (meth)acrylate monomers (Monomer A), (ii) from about 20 to 80 wt%, preferably from about 25 to 70 wt%, of the non-hydroxy monomer selected from the group consisting of vinyl aromatic hydrocarbons and lower alkyl ester of methacrylic acid (Monomer B), (iii) from about 1 to 55 wt%, preferably from about 5 to 45 wt%, and more preferably from about 10 to 40 wt%, at least one alpha-olefin having a total of from 7 to 20 carbon atoms (Monomer C), and (iv) from about 0 to 64 wt%, preferably from about 0 to 54 wt%, and more preferably from 0 to 40 wt%, of the non-hydroxy monomer selected from the group of alkyl esters of acrylic acid (Monomer D), with the proviso that Monomers A and B be employed in a combined amount of at least 35 wt%, preferably from about 45 to 90 wt%, and most preferably from about 55 to 80 wt%, of the total monomer mixture, and with the further proviso that Monomers C and D be employed in a combined amount of less than 65 wt%.

0019The alpha-olefins suitable in this invention as a component of the polymerization mixture comprise normally liquid aliphatic alpha-olefins having from 7 to 20 carbon atoms per molecule, and preferably from 8 to 16 carbon atoms per molecule. The term "normally liquid", when applied herein to such olefins, is intended to refer to olefins which are in the liquid state at ambient conditions (25°C, 1 atm). Suitable aliphatic alpha-olefins are branched and straight chain olefins with terminal olefinic unsaturation, and comprise compounds of the formula (I): <chemistry id="chem0001" num="0001"><img file="EP0225809A2_D0001.tif" /></chemistry> wherein Y¹, X¹ and X² are the same or different and are H or alkyl of from 1 to 17 carbon atoms, with the proviso that Y, X¹ and X² moieties contain a total of from 4 to 17 carbon atoms, preferably from 5 to 13 carbon atoms, more preferably from 6 to 11 carbon atoms, and most preferably from 7 to 9 carbon atoms.

0020A preferred class of olefins for use in this invention are aliphatic alpha-olefins of the formula (II): <chemistry id="chem0002" num="0002"><img file="EP0225809A2_D0002.tif" /></chemistry> wherein Y² is H or alkyl of from 1 to 5 carbon atoms and wherein X³ and X⁴ are the same or different and are H or alkyl of from 1 to 11 carbon atoms, with the proviso that the Y², X³ and X⁴ moieties contain a total of from 5 to 11 carbon atoms.

0021Such alkyl groups of formulae (I) and (II) may be branched or straight chained, and exemplary thereof are methyl, ethyl, n-butyl, iso-butyl, sec­butyl, tert-butyl, n-pentyl, iso-pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl, and the like. Exem­plary of suitable aliphatic alpha-olefins, therefore, are 1-heptene, 3-ethyl-1-pentene, 1-octene, 3-methyl-­1-heptene, 4-propyl-1-heptene, 1-nonene, 2-methyl-1-­heptene, 1-decene, 1-undecene, 1-dodecene, the terminally unsaturated tridecenes, tetradecenes, pentadecenes and hexadecenes, and the like. Such alkyl groups of formulae (I) and (II) may also be phenyl-substituted; e.g., phenyl methyl, 2-phenyl ethyl, 3-phenyl butyl and the like.

0022The selected alpha-olefin will preferably be characterized by a normal boiling point (i.e., at 1 atm) of at least about 100°C, more preferably from about 115 to 250°C, and more preferably from about 150 to 200°C. The alpha-olefin will also preferably be substantially free of water and trace metals, as dis­cussed below for the polymerization solvent, when the resins to be formed are intended for use as a component of electrostatic spray coatings.

0023Particularly preferred are mixed aliphatic alpha-olefins conventionally produced by ethylene oligomerization (i.e., the ethylene growth reaction).

0024The hydroxy-substituted alkyl (meth)acrylates which can be employed as Monomer A comprise members selected from the group consisting of the following esters of acrylic or methacrylic acid and aliphatic glycols: 2-hydroxy ethyl acrylate; 3-chloro-2-hydroxypropyl acrylate; 1-hydroxy-2-­acryloxy propane; 2-hydroxypropyl acrylate; 3-hydroxy­propyl acrylate; 2,3-dihydroxypropyl acrylate; 2-hydroxy-butyl acrylate; 4-hydroxybutyl acrylate; diethylene-glycol mono-acrylate; 5-hydroxypentyl acrylate; 6-hydroxyhexyl acrylate; triethyleneglycol mono-acrylate; 7-hydroxyheptyl acrylate; 1-hydroxy-2-­methacryloxy propane; 2-hydroxy-propyl methacrylate; 3-hydroxypropyl methacrylate; 2,3-dihydroxypropyl methacrylate; 2-hydroxybutyl methacrylate; 3-hydroxy­butyl methacrylate; 2-hydroxyethyl methacrylate; 4-hydroxybutyl methacrylate; 3,4-dihydroxybutyl methacrylate; 5-hydroxypentyl methacrylate; 6-hydroxyhexyl methacrylate; 1,3-dimethyl-3-­hydroxybutyl methacrylate; 5,6-dihydroxyhexyl methacrylate; and 7-hydroxyheptyl methacrylate. Although one of ordinary skill in the art will recog­nize that many different hydroxy-substituted alkyl (meth)acrylates including those listed above could be employed, the preferred hydroxy functional monomers for use in the resin of this invention are hydroxy-­substituted (meth)acrylates, meaning alkyl acrylates and methacrylates having a total of 5 to 7 carbon atoms, i.e., esters of C₂-C₃ dihydric alcohols and acrylic or methacrylic acids.

0025Most preferably, the hydroxy-substituted alkyl (meth)acrylate monomer comprises a compound of the formula (III): <chemistry id="chem0003" num="0003"><img file="EP0225809A2_D0003.tif" /></chemistry> wherein R⁴ is hydrogen or methyl and R⁵ and R⁶ are independently selected from the group consisting of hydrogen and alkyl of from 1 to 6 carbon atoms. Illustrative of these particularly suitable hydroxy-­substituted alkyl (meth)acrylate monomers are 2-hydroxy ethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate and 2-hydroxypropyl methacrylate.

0026The Monomer A can also comprise (meth)acrylic acid; i.e., acrylic acid or methacrylic acid, or a mixture thereof alone or together with any of the aforementioned hydroxy-substituted alkyl (meth)acrylate monomers.

0027The non-hydroxy monomers (Monomer B) comprise at least one member selected from the group consisting of vinyl aromatic hydrocarbon monomers and alkyl methacrylate monomers.

0028The vinyl aromatic hydrocarbons comprise monovinyl aromatic hydrocarbons containing from 8 to 12 carbon atoms and halogenated derivatives thereof having halo-substituted aromatic moieties (including styrene, alpha-methyl styrene, vinyl toluene, <u style="single">t</u>-butyl styrene, chlorostyrene and the like).

0029The non-hydroxy substituted alkyl methacrylate monomers which may be employed are meth­acrylates (as before, meaning esters of methacrylic acids). Preferred non-hydroxy unsaturated monomers are esters of C₁-C₄ monohydric alcohols and meth­acrylic acid, e.g., methylmethacrylate, ethylmeth­acrylate, butylmethacrylate, etc.

0030Particularly preferred are alkyl methacrylate monomers selected from the group consist­ing of monomers of the formula (IV): <chemistry id="chem0004" num="0004"><img file="EP0225809A2_D0004.tif" /></chemistry> wherein R⁷ is alkyl of from 1 to 3 carbon atoms. Particularly preferred are ethyl methacrylate and methyl methacrylate.

0031The non-hydroxy substituted alkyl acrylate monomers which may be employed as Monomer D are alkyl esters of acrylic acids. Preferred non-hydroxy alkyl acrylates are esters of C₁-C₄ monohydric alcohols and acrylic acid, e.g., methyl acrylate, ethyl acrylate, butyl acrylate, and the like.

0032The monomer mixture can additionally include optional monomers such as vinyl chloride, vinylidene chloride, acrylonitrile, methacrylonitrile, and vinyl acetate.

0033The total monomer mixture utilized in the polymerization process step will comprise (a) from about 5 to 45 wt%, and preferably from about 10 to 35 wt%, of Monomer A, (b) from about 20 to 80 wt%, pre­ferably from about 25 to 70 wt% of Monomer B, and (c) from about 1 to 55 wt%, more preferably from about 5 to 45 wt%, and most preferably from about 10 to 40 wt%, of the above alpha-olefins, and (d) from 0 to 64 wt%, and preferably from 0 to 54 wt%, of Monomer D, in addition to any optional monomers (discussed above). Generally, Monomer B will comprise a mixture of (1) an alkyl methacrylate in an amount of from about 0 to 80 wt%, more preferably from about 15 to 50 wt%, of the total monomer mixture, and (2) a monovinyl aromatic hydrocarbon (e.g., styrene and alpha-methyl styrene) which will be employed in an amount of from about 0 to 80 wt%, preferably from about 10 to 40 wt% of the total monomer mixture. Monomer A will typically com­prise a mixture of (1) a hydroxy-substituted alkyl meth-acrylate of formula III, which will be present in an amount of from about 5 to 45 wt%, more preferably from about 8 to 30 wt%, of the total monomer mixture, and (2) acrylic acid or methacrylic acid which will be employed (alone or together) in an amount from about 0 to 20 wt%, more preferably from about 1 to 15 wt%, of the total monomer mixture. However, the total amount of Monomers A and B should be at least 35 wt%, prefer­ably from about 45 to 90 wt%, and most preferably from about 55 to 80 wt%, of the total monomer mixture, and the total amount of Monomers C and D should be less than 65 wt%, preferably from about 10 to 55 wt%, and most preferably from about 20 to 45 wt%, of the total monomer mixture.

0034The remaining above-mentioned monomers may be present in an amount of up to 30 wt%, more typi­cally from 3 to 10 wt%, of the monomer mixture, where employed.

0035The organic polymerization solvents which can be employed comprise at least one member selected from the group consisting of ketones, ethers, glycols, glycol ethers, esters, keto ethers, ether esters, alcohols, nitro-substituted paraffins, aromatic solvents and halocarbon solvents. The organic moiety to which the ketone, and ether functional groups can be attached includes alkyl, typically about C₁ to C₂₀, preferably about C₁ to C₁₀, most preferably about C₁ to C₅ alkyl; aryl, typically about C₆ to C₁₄, prefer­ably about C₆ to C₁₀, most preferably C₆ aryl; cyclo­alkyl, typically about C₄ to C₂₀, preferably about C₆ to C₁₂, most preferably about C₆ to C₁₀ cycloalkyl; aralkyl and alkaryl wherein the alkyl and aryl groups thereof are described above. Suitable keto ethers include molecules of the formula (V): <chemistry id="chem0005" num="0005"><img file="EP0225809A2_D0005.tif" /></chemistry> wherein T¹ and T² are each hydrocarbyl containing from 1 to 10 carbon atoms, and T³ is straight or branched chain alkyl of from 1 to 6 carbon atoms. Illustrative of such keto ethers are CH₃C(O)CH₂CH₂OCH₂CH₃; C₃H₇C(O)CH₃H₆OC₃H₇; CH₃C(O)CH₂C(OCH₃)(CH₃)CH₃; CH₃C(O)CH₂C(OC₂H₅)(CH₃)CH₃; C₂H₅C(O)CH₂CH₂OC₄H₉; and the like. Nitro-paraffinic solvents include NO₂-­substituted alkanes of 2 to 5 carbon atoms. Halo­carbon solvents include chloro- and fluoro-substituted saturated hydrocarbons. Alcohol solvents include alkanols of 4 to 10 carbon atoms, and phenyl-­substituted alkanols of 7 to 10 carbon atoms. Ether alcohols include alkoxy-substituted alkanols of from 3 to 8 carbon atoms. Glycol solvents include di-hydroxy substituted alkanes of from 2 to 6 carbon atoms. Glycol ether solvents include compounds of the formula Rʹ-O-Rʺ wherein Rʹ is alkyl of from 1 to 6 carbon atoms, and Rʺ is hydroxy-substituted alkyl of from 2 to 6 carbon atoms.

0036Suitable ester solvents comprise normally liquid C₁ to C₁₃ alkyl esters of alkanoic acids having from 2 to 7 carbon atoms. Prepared ester solvents are those selected from the group consisting of compounds having the formula (VI): R¹ - <img file="EP0225809A2_D0006.tif" /> - O - R² (VI) wherein R¹ is a straight or branched chain alkyl of from 1 to 6 carbon atoms, and R² is a straight or branched chain alkyl of from 1 to 13 carbon atoms, with the proviso that R¹ and R² together contain from 6 to 17 carbon atoms, and mixtures thereof. The "R¹" group can also comprise C₂ to C₇ alkyl having one carbon replaced by an ether oxygen (e.g., C₂H₅-O-C₂H₄-, C₃H₇-O-C₂H₄, C₂H₅-O-C₃H₆-, and the like). Exemplary of such ester solvents are butyl acetates, hexyl acetates, pentyl acetates, pentyl propionates, isobutyl isobutyrate, heptyl acetates, methyl pentanoates, ethyl pentanoates, pentyl pentanoates, ethyl hexanoates, butyl hexano­ates, ethyl neopentanoate, methyl neoheptanoate, octyl acetates, nonyl acetates, decyl acetates, undecyl acetates, dodecyl acetates, tridecyl acetates and the like. Exemplary of esters wherein the carboxylic acid moiety is derived from an ether-containing acid (e.g., acids which are alkoxy-substituted) are ethyl 3-ethyoxypropionate, butyl 3-butoxypropionate, methyl 2-methoxyacetate, methyl 3-methoxypropionate, propyl 3-propoxypropionate and the like.

0037Especially preferred ester solvents of this invention are normally liquid esters selected from the group consisting of compounds of the formula (VII): <chemistry id="chem0006" num="0006"><img file="EP0225809A2_D0007.tif" /></chemistry> wherein R³ is a straight or branched-chain alkyl having from 5 to 13 carbon atoms, and mixtures thereof. Exemplary of such preferred ester solvents herein are pentyl acetates, hexyl acetates, heptyl acetates, octyl acetates, nonyl acetates, decyl acetates, undecyl acetates, dodecyl acetates, and tridecyl acetates. The term "normally liquid esters" as used herein is intended to refer to esters which are in the liquid state at ambient conditions (25°C, 1 atm).

0038Suitable ketone solvents include methyl amyl ketone, methyl isobutyl ketone, methyl propyl ketone, isophorone, cyclohexanone, diethyl ketone, dibutyl ketone, methyl isopropyl ketone, methyl sec­butylketone, benzophenone, mixtures thereof, and the like. Suitable ether solvents include dibutyl ether, tetrahydrofuran, anisole, dioctyl ether, 1,2-­dimethoxyethane, 1,4-dimethoxybutane. Suitable halocarbon solvents include 1,1,2-trichloroethane, tetrachloroethane and the like. Suitable nitroparaf­finic solvents include nitropropane and nitroethane. Suitable alcohols include 2-ethyl hexanol, diacetone alcohol, phenethyl alcohol, benzyl alcohol, amyl alcohols, hexyl alcohols, heptyl alcohols, and the like. Suitable glycol ethers, esters and mixed ether and ester solvents include ethylene glycol diacetate, propylene glycol diacetate, Cellosolve® acetate (registered trademark of the Union Carbide Corporation), butyl Cellosolve, Cellosolve, the Carbitols® (registered trademark of the Union Carbide Corporation), methoxy propyl acetate, ethoxy propyl acetate and the like. Suitable aromatic solvents comprise alkyl-substituted benzenes of the formula (VIII): <chemistry id="chem0007" num="0007"><img file="EP0225809A2_D0008.tif" /></chemistry> wherein p is an integer of from 1 to 4, and X is in each instance in which it appears independently selected from the group consisting of straight and branched-chain alkyl of from 1 to 4 carbon atoms.

0039Illustrative of suitable alkyl-substituted benzene solvents for use in the solvent blends of this invention are ethyl benzene, isopropyl benzene, <u style="single">n</u>-propyl benzene, 1-methyl-3-ethylbenzene, 1-methyl-4-­ethylbenzene, 1,3,5-trimethylbenzene, 1-methyl-2-­ethylbenzene, 1,2,4-trimethylbenzene, isobutylbenzene, <u style="single">sec</u>-butylbenzene, 1-methyl-3-isopropylbenzene, 1-methyl-4-isopropylbenzene, 1,2,3-trimethylbenzene, 1-methyl-2-isopropylbenzene, 1,3-diethylbenzene, 1-methyl-3-<u style="single">n</u>-propylbenzene, <u style="single">n</u>-butylbenzene, 1,4-­diethylbenzene, 1,3-dimethyl-5-ethylbenzene, 1,4-­dimethyl-2-ethylbenzene, 1,3-dimethyl-4-ethylbenzene, 1,2-dimethyl-4-ethylbenzene, 1,2,4,5-tetramethyl­benzene, 1,2,3,5-tetramethylbenzene and the like, toluene, xylene, cumene, alkyl-substituted benzenes in which the alkyl substituent comprises a total of at least 2 carbon atoms when the benzene ring is mono­alkyl substituted and of at least 3 carbon atoms when the benzene ring is substituted by two or more alkyl groups, and aromatic groups distributed by a cyclic aliphatic ring (e.g., tetrahydronaphthalene), and mixtures of the foregoing.

0040The aromatic solvent component can also contain up to about 50 wt%, preferably less than about 40 wt%, and more preferably up to about 25 wt%, of other hydrocarbon solvents such as C₆ to C₁₁ aromatic solvents not satisfying the definition of formula III above, as well as C₆ to C₁₁ saturated aliphatic and cycloaliphatic hydrocarbons.

0041Especially preferred such polymerization solvents comprise from about 60 to 90 wt% of an organic solvent (e.g., a normally liquid ester of formula VI) and from about 10 to 40 wt% of an aromatic solvent of formula VIII.

0042The polymerization solvents are preferably characterized by a normal boiling point (at 25°C, 1 atm) of at least about 100°C, more preferably from about 115 to 250°C, and most preferably from about 150 to 200°C. In addition, when the polymers of the present invention are intended for use as a component of electrostatic spray coatings, the polymerization solvents are preferably substantially free of water (more preferably having a water content of less than 0.5 wt%) and trace metals (more preferably having a trace metals content of less than 0.004 wt%), and are characterized by a resistivity of at least 15 megohms, as determined by Ransburg resistivity meter.

0043In preparing the polymers of this invention, the selected monomers, including the desired hydroxy-­substituted alkyl (meth)acrylate, non-hydroxy substituted alkyl (meth)acrylate and alpha-olefin, together with any modifying or other monomers, may be mixed and reacted by conventional free radical ini­tiated polymerization in the selected polymerization solvent in such proportions as to obtain the copolymer desired. A large number of organic, free radical initiators are known in the art and are suitable for the purpose. These include: benzoyl peroxide; lauryl peroxide; <u style="single">t</u>-butyl-hydroperoxide; acetylcyclohexyl­sulfonyl peroxide; di-isobutyryl peroxide; <u style="single">t</u>-butyl-­peroxypivalate; decanoyl peroxide; azobis-(2-methyl­propionitrile); 2-<u style="single">t</u>-butylazo-2-cyanobutane; tertiary butyl perbenzoate, dicumyl peroxide, ethyl 3,3-(t-­amylperoxy)butyrate, ethyl 3,3-di(t-butylperoxy) butyrate, t-butyl cumyl peroxide, and di(butyl cumyl) peroxide, and di-t-butyl peroxide, and other dialkyl peroxides, peroxy ketals, and peroxyesters.

0044The total monomer mixture to be employed in preparing the polymers according to the process of this invention will generally comprise from about 30 to 95 wt%, preferably from about 50 to 90 wt%, of the total mass of monomers and solvent passed to the poly­merization reaction vessel. Thus, the polymerization solvent will generally comprise from about 5 to 70 wt%, preferably from about 10 to 50 wt%, of the total mass of monomers and solvent passed to the polymeriza­tion vessel. The quantity of free radical initiators employed as catalyst in the reaction can also vary widely and will generally be present in an amount of from about 0.5 to 10 wt% of the total monomer compo­nents charged to the reaction mixture.

0045The conditions of temperature and pressure for conducting the polymerization reaction can vary widely. Generally, the polymerization will be conducted at a temperature of from about 100 to 240°C (and preferably from about 130 to 210°C) at atmos­pheric pressure. Pressures of from about 10 to 500 psig are entirely suitable, although higher or lower pressures can be employed. The polymerization reac­tion can be carried out in any of the conventional equipment employed by the industry for such reactions. Thus, the reaction vessel can comprise a stirred reactor in which an inert atmosphere (e.g., N₂, Ar) is maintained during the polymerization to avoid reac­tions with gaseous oxygen which compete, or interfere, with the desired polymerization reaction. However, the improved high solids resins of the present inven­tion can also be formed by a polymerization conducted in the presence of air, thereby providing a polymeri­zation process which is not critically sensitive to equipment leaks or malfunctions whereby air enters into conventional process equipment.

0046In order to form resins of improved color, it is preferred that the polymerization be conducted in the substantial absence of conjugated olefinic impurities comprising conjugated diolefins, internally unsaturated monoolefins in which the olefinic double bond is conjugated with an aromatic ring (e.g., as in indene); and internally unsaturated monoolefins which are alpha, beta unsaturated ketones, esters, amides and acids. More preferably, the polymerization mix­ture contains less than 100 ppm of such conjugated olefinic impurities.

0047The polymerization process can be carried out batchwise, semi-continuously, or continuously. The monomers and solvent system can be premixed or passed separately to the polymerization vessel alone, or in combination with the free radical initiators and other components. In addition, the components of the polymerization solvent may be premixed with each other or with any other material to be charged (e.g., with any of the monomers) or may be fed separately to the vessel.

0048The method of addition of the monomers can vary as described above, and is important in determin­ing the final polymer composition. More specifically, the amount of alpha-olefin which is incorporated into the polymer is dependent upon the method of monomer addition. Since the reactivity of the alpha-olefin is much less than the reactivity of the other monomers, a high concentration of the alpha-olefin relative to the other monomers in the reaction zone is beneficial for incorporation of a significant amount of alpha-olefin into the polymer structure. Accordingly, when high alpha-olefin incorporation is desired, it is desirable to combine a large portion of the alpha-olefin with the mass of the polymerization solvent and introduce this solution to the reaction vessel separately from and prior to the introduction of the remaining monomers (e.g., Monomers A, B, and D and the balance of the alpha-olefin monomer). Depending on the desired amount of alpha-olefin incorporation into the polymer, the initial amount of alpha-olefin combined with the polymerization solvent can be adjusted, with the balance of the alpha-olefin combined with the other monomers. Generally, the higher the amount of alpha-olefin initially added to the polymerization solvent, the greater the alpha-olefin incorporation into the polymer structure.

0049Another method to increase the alpha-olefin incorporation into the polymer is to increase the addition time of the other monomers, thereby increas­ing the relative concentration of the alpha-olefin relative to the other monomers.

0050In one embodiment of the process of this invention, substantially all of the solvent is added to the reaction flask and is heated to the desired reaction temperature. At this point, an addition of substantially all (i.e., at least about 80 wt%) of the monomer is begun. Minor amounts of one or more of the monomers; i.e., up to about 20 weight percent of the total monomer weight may be placed in the reaction vessel with the solvent. The addition is carried out over at least about 30 minutes. Not all of the monomers need be mixed together; rather, separate additions of different monomers or different ratios of different monomers, may be used. Preferably, the addi­tion time should be in the range of about 1 to 15 hours, most preferably 2 to 10 hours.

0051In a preferred embodiment of the process of this invention, from about 10 to 100 wt% (and more preferably from at least about 80 wt%, and most preferably at least about 90 wt%) of the alpha-olefin monomer is combined with the mass of the polymeriza­tion solvent and introduced to the reaction vessel separately from (and preferably prior to) the intro­duction of the remaining monomers (e.g., Monomers A, B and D, and the balance of the alpha-olefin monomer), and the balance of the alpha-olefin is charged to the reaction vessel along with the other such monomers.

0052The initiators which are utilized in the instant invention may be either mixed with the monomer or added separately over the general period of the monomer addition. In view of the high reaction tem­perature involved, addition of any major amount of the initiator to the solvent prior to the addition of the monomer will be of little or no effect.

0053Addition times of both initiators and monomers may vary and the various monomers may be added over regular periods of time, periodically, or over gradually increasing or decreasing periods of time, as long as the total amount of monomer addition is substantially within the ranges indicated.

0054The initiator should be added to the reaction over at least 30 minutes and preferably over the same or longer period of time that Monomers A, B and D are added. This can be accomplished, for example, by introducing the initiator to the reaction vessel simultaneously with the monomer feed, followed by the introduction of an additional amount of the initiator (generally from about 5 to 30 wt% of the total initiator to be charged) with stirring, to bring the polymerization of any remaining monomers to com­pletion. Initiator levels should vary from about 0,5 percent to 10 percent, based on the total monomer weight, preferably 0.5 to 5 percent.

0055The time for which the polymerization reaction is allowed to proceed can also vary widely and will generally range from about 0.5 to 15 hours, preferably from about 1 to 10 hours.

0056Reaction temperature should be maintained within the desired temperature ranges following monomer addition for a time sufficient to cause con­version of all the monomer to polymer. This is usually measured by determining the solids content of the reaction mixture by measuring the amount of sol­vent that evaporates, when test samples are held for the desired time at the selected temperature (e.g., for about 20 minutes at 220°C). The term "solids content" does not refer to whether the polymer pre­pared herein is liquid or solid in nature, but rather refers to the amount of material which is left behind after the evaporation at the selected conditions. Thus, the term "solids content" is synonymous with the term "percent non-volatile matter" or "percent NVM" at the selected conditions.

0057At this point, the reaction solvent may be removed by either increasing the heat or applying a vacuum or both. It is preferred that vacuum be utilized in addition to heat to minimize heat degrada­tion of the polymer. Alternatively, and more prefer­ably, the solvent can remain with the polymer resins for formulation of coatings therefrom, as will be described more completely below.

0058The acrylic resins produced by the process of this invention are preferably liquid in nature and characterized by weight average molecular weights (M_w) from abut 800 to 15,000, and more preferably from about 1,000 to 10,000, and most preferably from about 1,000 to 8,000. Also, the acrylic resins produced by the process of this invention are preferably charac­terized by number average molecular weights (M_n) falling within a range of from about 500 to 8,000, and more preferably from about 700 to 5,500, and by M_w/M_n ratios of from about 2 to 5, and more typically from about 2 to 4. Furthermore, the acrylic resins of the present invention will be preferably characterized by kinemmatic viscosities at 65% NVM of up to 10,000 cs, and more preferably from 100 to 5,000 cs (as deter­mined by ASTM D445). These acrylic resins can then be employed in the formulation of coatings with or with­out the addition of other solvents. The components of such coating compositions formulated using these acrylic resins can be any of the conventional cross-­linking agents, catalysts, antioxidants, UV absorbers and stabilizers, surface modifiers, wetting agents as well as pigments. These materials are conventional and a more complete description thereof is not neces­sary for a full understanding of this invention. For example, illustrative conventional UV absorbers and stabilizers are illustrated by those discussed in European Patent Application 29,594.

0059The coatings prepared by use of the acrylic resins of this invention can be applied to substrates, such as automobiles and the like, using conventional methods known to the art, such as roller coating, spray coating, electrostatic spray coating, dipping or brushing. Of course, the particular application tech­nique will depend on the particular substrate to be coated and the environment in which the coating operation is to take place. A particularly preferred technique for applying the high solids compositions, particularly when applying the same to automobiles as top coats, is spray coating through the nozzle of a spray gun.

0060In accordance with another embodiment of the present invention, an improved method for formulating a high solids acrylic resin coating, intended for use in electrostatic spray applications, is provided wherein the acrylic resin, which is formed by conven­tional techniques or by use of the aforementioned improved polymerization process, is formulated into a high solids coating by use of a cutting solvent com­prising a mixture of any of the above-discussed solvents, with or without one or more of the alpha-­olefins of formula (I). The coating composition is preferably formulated to contain high solids (that is, at least about 50 wt% solids) and preferably from about 50 to 90 wt% solids, and most preferably from about 55 to 80 wt% solids.

0061As with the previously discussed embodiment of this invention, the acrylic resin coatings of this invention can be employed in combination with any of the conventional cross-linking agents, catalysts, anti-oxidants, UV absorbers and stabilizers, surface modifiers, wetting agents and pigments which are known in the art. These materials, again, are conventional and a more complete description thereof is not neces­sary for full understanding of this invention. For example, illustrative conventional UV absorbers and stabilizers are those illustrated by the discussion of European Patent Application 29,594 and by the surface modifiers and pigments described in European Patent Application 29,339, the disclosures of which are hereby incorporated by reference.

0062The novel coating compositions of this invention can be applied to a variety of substrates such as metal, wood, glass, and plastics such as polystyrene, polyurethane and copolymers of styrene, by any of the usual application methods such as by spraying, electrostatic spraying, dipping, brushing, flow coating, rolling and the like. Most preferably, the novel coating compositions of this invention are applied by electrostatic spraying.

0063The thus-formed coatings can be air-dryed or baked. The resulting coating is preferably from about 0.2 to 3 mils thick, and preferably 0.4 to 2.5 mils thick, and can be rubbed or polished in accordance with conventional techniques, if desired, to improve smoothness or apparent gloss or both.

0064After the novel coating composition is applied, the coating is preferably cured at about 80 to 250°C for about 1 to 45 minutes.

0065While the acrylic resins of this invention have been described above for use in coatings, it will also be understood that such low molecular weight resins may be used in any of a varied number of end applications. For example, they may be used as plas­ticizers for rigid, inflexible polymeric systems. In addition, they may be utilized in combination with conventional curing agents to form films and plastic articles, and as binders and sizers. Examples of the curing agents which may be utilized for preparing cross-linked polymeric products include polyepoxides, di-isocyanates and urea-aldehyde, benzoguanamine­aldehyde, or melamine-aldehyde condensation products and the like. Particularly desired are the melamine-­formaldehyde condensation products, such as polymethoxymethyl melamines, preferably the hexa­methoxymethyl melamines. When melamine-formaldehyde or urea-formaldehyde curing agents are utilized, it is preferred that an acid catalyst (such as butyl acid phosphate, paratoluene sulfonic acid, naphthalene sulfonic acid, naphthalene di-sulfonic acids and dodecyl benzene sulfonic acid [as described in U.S. Patents 3,979,478 and 4,075,176], and amine salts of any of the foregoing) be employed to increase the cure rate.

0066The process and compositions of this invention can be further illustrated by reference to the following examples, wherein parts are by weight unless otherwise indicated.

0067In the Examples, unless otherwise indicated, the following test procedures or devices were used for determining the corresponding properties: <tables id="tabl0001" num="0001"><img file="EP0225809A2_D0009.tif" /></tables>

0068The hexylacetate and heptylacetate used in the Examples were products of an esterification reac­tion between acetic acid and the corresponding hexyl or heptyl alcohol. The alcohol precursors themselves were formed in a commercial oxo reaction and each comprised a mixture of normal- and iso-alcohols. (Similar results would be achieved if pure normal- or iso-hexyl or heptyl alcohols were used.)

0069In the Examples, AROMATIC™ 100 solvent (manufactured by Exxon Company U.S.A.) comprised a narrow-cut aromatic solvent containing about 40 wt% trimethyl benzenes, 35 wt% methyl ethyl benzenes, 10 wt% propyl and isopropyl benzenes, 3 wt% ethyl dimethyl benzenes, 2 wt% methyl (n- and iso-) propyl benzenes, 2 wt% diethyl benzenes, &lt;1 wt% each of mono butyl benzenes and tetramethyl benzenes, 6 wt% xylenes and minor amounts of ethyl benzene, C₁₀ and C₁₁ saturates and unknowns. AROMATIC™ 150 solvent (manu­factured by Exxon Company U.S.A.) comprised a narrow-cut aromatic solvent containing about 23 wt% tetra-methyl benzenes, 22 wt% ethyl dimethyl benzenes, 15 wt% mono-, di- and tri-methyl indanes, 8 wt% diethyl benzenes, 8 wt% naphthalene, 5 wt% trimethyl benzenes, 2 wt% indane, and about 1 wt% or less of methyl ethyl benzenes, propyl benzenes, methyl propyl benzenes, butyl benzenes, hexyl benzenes, indene, methyl naphthalenes, xylenes, and unknowns.

0070Number average molecular weights (M_n) and weight average molecular weights (M_w) were found by gel permeation, with a polystyrene standard (using a Waters GPC-1 instrument).

0071Non-volatile matter (NVM) measurements were made by mixing a weighed sample of the product resin-­polymerization solution with sufficient toluene to produce a 10:90 wt:wt resin product solution:toluene mixture and thereafter casting a thin film (about 0.05 mm) which was baked one hour at 150°C in air, followed by weighing the residual material.

EXAMPLE 1

0072To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 688g of heptylacetate together with 344g of 1-decene. Nitrogen was continuously blown into the apparatus at a slow rate. The solvent plus 1-decene was heated over a 0.5 hour period to 160°C polymerization temperature. A mixed liquid feed, comprising a blend of 240g styrene, 1136g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid, and the initiator, 24g of tert­butyl peroxide were placed into a separate one gallon container. The monomer plus initiator solution was pumped to the reaction flask over a 187 minute period at 160°C with continual stirring and N₂ flow. After the addition was complete, the reaction mixture was stirred for an additional 23 minutes at 160°C. Then an additional 12g tert-butyl peroxide was added and the mixture stirred at 160°C temperature for another 1.5 hours. The reaction mixture then was cooled with stirring and analyzed. The resin formed had:

0073Viscosity (cps) 21,000 Color (Pt/Co) 30.0 Mn 5,700 Mw 14,700 Mw/Mn 2.6 % 1-decene in polymer 12.4 1-decene conversion, % ∼ 100

0074This example has demonstrated essentially complete incorporation of 1-decene into the copolymer.

EXAMPLE 2

0075To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 1032g of heptyl acetate solvent. N₂ was slowly blown into the apparatus continually. The solvent was heated over a 0.5 hour period to 160°C polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 896g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl meth­acrylate, 64g of acrylic acid, 240g 1-decene, and the initiator, 24g of tert-butyl peroxide, were placed into a separate one gallon container. The monomer plus initiator solution was pumped to the reaction flask over a 180 minute period at 160°C with continual stirring and N₂ flow. After the monomer blend was added, the reaction mixture was stirred an additional 60 minutes at the polymerization temperature. Then an additional 12g tert-butyl peroxide was added and the mixture stirred at 160°C temperature for another 1.5 hours. The reaction mixture then was cooled with stirring and analyzed. The resin formed had:

0076NVM (%) 68.1 Viscosity (cps) 8,100 Color (Pt/Co) 35 Mn 3,690 Mw 10,390 Mw/Mn 2.8 % 1-decene in polymer 7.0 1-decene conversion 69.6

0077This example has demonstrated reduced incorporation 1-decene in copolymer when 1-decene was mixed with the monomer feed.

EXAMPLE 3

0078To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 778g of heptyl acetate solvent N₂ was slowly blown into the apparatus continually. The solvent was heated over a 0.5 hour period to 160°C polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 896g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl meth­acrylate, 64g of acrylic acid, and 240g of 1-decene, was placed into a separate one gallon container and 36g of t-butyl perbenzoate initiator in 254g heptyl acetate solvent was placed in a separate container. The monomer feed and initiator solutions were separately pumped to the reaction flask at 160°C with continual stirring and N₂ flow. The monomer addition time was 187 minutes and the initiator addition time was 240 minutes. When the addition was complete, the reaction mixture was stirred an additional hour at 160°C. Then the reaction mixture was cooled and analyzed. The resin formed had:

0079NVM (%) 67.5 Viscosity (cps) 11,750 Color (Pt/Co) 20 Mn 2,100 Mw 10,400 Mw/Mn 5 % 1-decene in polymer 6.2 1-decene conversion, % 61

EXAMPLE 4

0080To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 994g heptyl acetate solvent together with 200g of 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene were heated over a 0.5 hour period to 160°C polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid, 300g 1-decene, and the initiator, 48g tert-butyl peroxide, were placed into a one gallon container. This monomer plus initiator solution was pumped to the reaction flask at 160°C with continual stirring and N₂ flow. The initial rate of addition was approximately 500 ml over a 30 minute period, followed by the balance of the amount over 165 min­utes. After the monomer blend was added, the reaction mixture was stirred for an additional 30 minutes at the polymerization temperature. Then a second charge containing 12g tert-butyl peroxide initiator in 38g Aromatic™ 150 solvent and 50g heptyl acetate was added to the reaction flask over a 70 minute period at 160°C, with continual stirring and N₂ flow. When the second addition was complete, the reaction mixture was stirred an additional 30 minutes at 160°C. The reac­tion mixture was then cooled with stirring and analyzed. The resin formed had:

0081NVM (%) 64.3 Viscosity (cps) 2,130 Color (Pt/Co) 14 Mn 2,660 Mw 7,470 Mw/Mn 2.8 % 1-decene in polymer 12.8 1-decene conversion, % 57.3

EXAMPLE 5

0082To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 944g heptyl acetate solvent together with 200g of 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene were heated over a 0.5 hour period to 160°C polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid, 300g 1-decene, and the initiator, 48g tert-butyl peroxide, were placed into a separate one gallon container. The monomer plus initiator solution was pumped to the reaction flask over a 300 minute period at 160°C with continual stirring and N₂ flow. The initial rate of addition was approximately 500 ml over a 30 minute period, followed by the balance of the amount over 270 minutes. After the addition was completed, the reaction mixture was stirred an additional 30 minutes. Then a second charge containing 12g tert-butyl peroxide initiator in 38g Aromatic™ 150 and 50g heptyl acetate was added to the flask over a 75 minute period at 160°C with con­tinual stirring and N₂ flow. When the second addition was complete, the reaction mixture was stirred an additional 30 minutes at 160°C, and then cooled and analyzed. The resin formed had:

0083NVM (%) 64.8 Viscosity (cps) 1,640 Color (Pt/Co) 20 Mn 1,860 Mw 6,280 Mw/Mn 3.4 % 1-decene in polymer 13.4 1-decene conversion 60.8

EXAMPLE 6

0084To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 944g heptyl acetate solvent together with 100g 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene was heated over a 0.5 hour period to 160°C polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid, 400g 1-decene, and the initiator, 48g butyl peroxide, were placed into a one gallon container. The monomer plus initiator solution was pumped to the reaction flask over a 288 minute period at 160°C with continual stirring and N₂ flow. The initial rate of addition was approximately 633 ml over a 38 minute period, followed by the balance of the amount over 250 minutes. After the addition was com­pleted, the reaction mixture was stirred an additional 30 minutes. Then a second charge containing 12g tert-butyl peroxide initiator in 38g Aromatic™ 150 solvent and 50g heptyl acetate was added to the flask over a 70 minute period at 160°C with continual stirring and N₂ flow. When the second addition was complete, the reaction mixture was stirred an addi­tional 30 minutes at 160°C, and then cooled and analyzed. The resin formed had:

0085NVM (%) 63.5 Viscosity (CPS) 1,050 Color (PT/CO) 16.5 Mn 2,610 Mw 5,260 Mw/Mn 2.0 % 1-decene in polymer 11.6 1-decene conversion 51.7

EXAMPLE 7

0086o a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 994g heptyl acetate solvent together with 100g of 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene was heater over a 0.5 hour period to 165 polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid, 400g of 1-decene, and the ini­tiator, 48g of tert-butyl peroxide, were placed into one gallon container. The monomer plus initiator solution was pumped to the reaction flask over a 360 minute period at 165°C with continual stirring and N₂ flow. The initial rate of addition was approximately 1,000 ml over a 60 minute period, followed by the balance of the amount over 300 minutes. After the addition was complete, the reaction mixture was stirred an additional 30 minutes. Then a second charge containing 12g tert-butyl peroxide initiator in 38g Aromatic™ 150 solvent and 50g heptyl acetate was added to the flask over a 75 minute period at 165°C with continual stirring and N₂ flow. When the second addition was complete, the reaction mixture was stirred and additional 30 minutes at 165°C, and then cooled and analyzed. The resin formed had:

0087NVM (%) 63.9 Viscosity (cps) 980 Color (Pt/Co) 18.5 Mn 2,130 Mw 6,210 Mw/Mn 2.9 % 1-decene in polymer 12.2 1-decene conversion 54.5

EXAMPLE 8

0088To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 944g heptyl acetate solvent together with 100g of 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene were heated over a 0.5 hour period to 160°C polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid, 400g of 1-decene, and the ini­tiator, 48g of tert-butyl peroxide, were placed into a one gallon container. The monomer plus initiator solution was pumped to the reaction flask over a 345 minute period at 160°C with continual stirring and N₂ flow. The initial rate of addition was approximately 1,000 ml over a 60 minute period, followed by the balance of the amount over 285 minutes. After the addition was completed, the reaction mixture was stirred an additional 30 minutes. Then a second charge containing 12g tert-butyl peroxide initiator in 38g Aromatic™ 150 solvent and 50g heptyl acetate was added to the flask over a 70 minute period at 160°C with continual stirring and N₂ flow. When the second addition was complete, the reaction mixture was stirred an additional 30 minutes at 160°C, and then cooled and analyzed. The resin formed had:

0089NVM (%) 64.8 Color (Pt/Co) 19 Mn 2,930 Mw 8,820 Mw/Mn 3.6 % 1-decene in polymer 13.4 1-decene conversion 60.8

EXAMPLE 9

0090To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirred (made of 316 stainless steel) and a thermometer, was charged 832g heptyl acetate solvent together with 300g 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene were heated over a 0.5 hour period to 170°C polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid, and 200g 1-decene were placed into a separate one gallon container and 60g of tert-­butyl peroxide as initiator in 100g Aromatic™ 150 solvent and 100g heptyl acetate solvent was placed in a separate container. The monomer feed and initiator solutions were separately pumped to the reaction flask at 170°C with continual stirring and N₂ flow. The monomer mixture was added at the rate of about 1,000 ml during the first 1/2 hour, and the rest at the rate of 250 ml/hr over 330 minutes. The initiator solution was added continuously over a 480 minute period time period. The reaction mixture then was cooled with stirring and analyzed. The resin formed had:

0091NVM (%) 66.9 Viscosity (cps) 740 Color (Pt/Co) 17.5 % 1-decene in polymer 16.1 1-decene conversion 75.5

0092This example has demonstrated essentailly complete incorporation of 1-decene into the copolymer.

EXAMPLE 10

0093To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 832g heptyl acetate solvent together with 300g 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene were heated over a 0.5 hour period to 170°C polymerization temperature. The mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid and 200g 1-decene were placed into a one gallon container and 60g of tert-butyl peroxide as initiator in 100g of Aromatic™ 150 solvent and 100g of heptyl acetate solvent was placed in a separate container. The monomer feed and initiator solutions were separately pumped to the reaction flask at 170°C with continual stirring and N₂ flow. The monomer mixture was added at the rate of about 1,000 ml/hour during the first 1 hour, and the rest at the rate of 250 ml/hour over a 230 minute time period. The ini­tiator solution was added continuously over a 415 minute time period. The reaction mixture then was cooled with stirring and analyzed. The resin formed had:

0094NVM (%) 66.5 Viscosity (cps) 1,000 Color (Pt/Co) 16 Mn 5,700 Mw 14,700 Mw/Mn 2.6 % 1-decene in polymer 15.6 1-decene conversion 72.7

EXAMPLE 11

0095To a four-necked, five liter found bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 832g heptyl acetate solvent together with 400g of 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene were heated over a 0.5 hour period to 170°C polymerization temperature. A mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid and 100g 1-decene were placed into a separate one gallon container and 60g of tert-butyl peroxide as initiator in 100g of Aromatic™ 150 solvent and 100g heptyl acetate solvent was placed in a separate container. The monomer feed and initiator solutions were separately pumped to the reaction flask at 170°C with continual stirring and N₂ flow. The monomer mixture was added at the rate of about 1,000 ml/hour during the first one hour, and the rest at the rate of 250 ml/hour over a 215 minute time period. The initiator was added continuously over a 410 minute time period. The reaction mixture then was cooled with stirring and analyzed. The resin formed had:

0096NVM (%) 66.5 Viscosity (cps) 1,060 Color (Pt/Co) 18.5 % 1-decene in polymer 15.6 1-decene conversion 72.7

EXAMPLE 12

0097To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 672g heptyl acetate solvent together with 400g of 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus decene were heated over a 0.5 hour period to 170°C polymerization temperature. The mixed monomer feed, comprising a blend of 400g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid and 100g 1-decene were placed into a separate one gallon container and tert-butyl peroxide in initiator in 100g Aromatic™ 150 and 100g heptyl acetate solvent was placed in a separate con­tainer. The monomer feed and initiator solutions were separately pumped to the reaction flask at 170°C with continual stirring and N₂ flow. The monomer mixture was added at the rate of about 1,000 ml/hour during the first hour and the rest at the rate of 250 ml/hour over a 225 minute time period. The initiator solution was added continuously over a 405 minute time period, and therefore stirring at polymerization was con­tinued. The reaction mixtures then was cooled with stirring and analyzed. The resin formed had:

0098NVM (%) 69.7 Viscosity (cps) 3,300 Color (Pt/Co) 17.9 Mn 2,130 Mw 7,680 Mw/Mn 3.6 % 1-decene in polymer 12.9 1-decene conversion 62.9

EXAMPLE 13

0099To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 944g heptyl acetate solvent together with 200g 1-hexadecene. N₂ was slowly blown into the apparatus continually. The solvent plus hexadecene were heated over a 0.5 hour period to 160°C polymerization tem­perature. The mixed monomer feed, comprising a blend of 240g styrene, 636g of butyl acrylate, 480g each of 2-hydroxyethyl methacrylate and methyl methacrylate, 64g of acrylic acid, 300g of 1-decene, and the ini­tiator, 48g tert-butyl peroxide, were placed into a one gallon container. The monomer plus initiator solution was pumped to the reaction flask over a 300 minute period at 160°C with continual stirring and N₂ flow. The initial rate of addition was approximately 500 ml over a 30 minute period, followed by the balance of the amount over 270 minutes. After the addition was completed the reaction mixture was stirred an additional 30 minutes. Then a second charge containing 12g tert-butyl peroxide initiator in 38g Aromatic™ 150 solvent and 50g heptyl acetate was added to the flask over a 75 minute period at 160°C with continued stirring and N₂ flow. When the second addition was complete, the reaction mixture was stirred an additional 30 minutes at 160°C, and then cooled and analyzed. The reaction mixture was then cooled with stirring. The resin formed had:

0100NVM (%) 65.1 Viscosity (cps) 2,600 Color (Pt/Co) 18.5 Mn 2,670 Mw 7,670 Mw/Mn 2.6 % 1-decene in polymer 62.9 1-decene conversion 13.8

0101This example has demonstrated essentially complete incorporation of 1-decene into the copolymer.

COMPARATIVE EXAMPLE 14

0102The procedure of Example 11 was repeated using a monomer mixture comprising 240g styrene, 636g butyl acrylate, 480g 2-hydroxyethyl methacrylate, 480g methyl methacrylate, 64g acrylic acid and 100g decane (instead of 1-decene), and using 50g tertiary butyl peroxide initiator in 840g heptyl acetate to which 400g decane was added in the reaction vessel prior to feeding the monomer mixture. The polymerization was carried out in the following sequence at polymeriza­tion conditions: monomer mixture added over 305 minutes time period; continued stirring; additional initiator feed (10g tertiary butyl peroxide in 30g AROMATIC 150™ solvent) begun at 310 minutes and con­cluded at 365 minutes; stirred for additional 30 minutes, for a total polymerization time of 395 minutes.

0103Phase separation of the polymer and solvent phases was observed throughout the reaction, and the lower resin phase was observed to be cloudy with suspended resin solids distributed in the lower layer.

EXAMPLE 15

0104To a four-necked, five liter round bottomed flask fitted with a one liter dropping funnel, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 512g of hexyl acetate as polymerization sol­vent, together with 128g of 2,4,4-trimethyl-1-pentene (TMP) monomer. Air was blown into the apparatus at the rate of 8cc/min, and stirring at 250 RPM was com­menced. The solvent was heated over a 0.5 hour period to 140°C. A blend of 480.0g styrene, 480.0g butyl acrylate, 240.0g 2-hydroxyethyl methacrylate and 6 wt% of t-butyl perbenzoate as initiator (based on total weight of the monomers and initiator), was placed in the dropping funnel and added to the polymerization solvent with stirring and at the metered air-flow over a three hour period. Temperature was maintained between 138-145°C. After all the monomer blend was added, the reaction mixture was stirred for an addi­tional 30 minutes at 140°C. At this point a final amount of 6.0g of t-butyl perbenzoate in 6.0g of hexyl acetate was added slowly and the mixture stirred at 140°C for a final two hours.

0105The data thereby obtained indicated the polymer resin so produced had a Pt/Co color of 20, a viscosity of 3700 cps, and contained 69.1% NVM. The TMP conversion was 51%, and there was 4.9 wt% TMP incorporated into the polymer.

0106When this experiment was repeated without the TMP monomer, the resulting resin had a Pt/Co color of 28, a resin viscosity of 2880 cps, and only 65.7% NVM.

EXAMPLE 16

0107To a four-necked, five liter round bottomed flask fitted with two liquid feed tubes, a water jacketed reflux condenser, an air driven stirrer (made of 316 stainless steel) and a thermometer, was charged 650g of heptyl acetate solvent together with 1195g of 1-decene. N₂ was slowly blown into the apparatus continually. The solvent plus dodecene were heated over a 0.5 hour period to 160°C polymerization tem­perature. The mixed monomer feed, comprising a blend of 1140g of methyl methacrylate, and 360g of acrylic acid were placed into a one gallon container and 65g of tert-butyl peroxide as initiator in 20g heptyl acetate and 80g Aromatic™ 100 solvent was placed in a separate 200 ml container. The monomer feed and initiator solutions were separately pumped to the reaction flask at 160°C with continual stirring and N₂ flow. The monomer mixture was added at the rate of about 250 ml/hour over 340 minutes. The initiator solution was added continuously over a 400 minute period of time. The reaction mixture then was cooled with stirring and analyzed. The resin formed had:

0108NVM (%) 63.9 Viscosity (cps) 14,200 1-decene conversion 55.4 % 1-decene in polymer 30.0

0109It will be obvious that various changes and modifications may be made without departing from the invention and it is intended, therefore, that all matter contained in the foregoing description shall be interpreted as illustrative only and not limitative of the invention.