Patent GB-691908-A (GB)
Title: Polymerization process
IPC: C08F12/04
Filed: 1949-09-21
Abstract: Polymers and copolymers of vinyl aryl compounds are made, e.g as beads, by polymerizing in bulk, solution or aqueous emulsion or suspension, in the presence of a mixture of catalysts comprising a benzoyl-type peroxide and at least one compound selected from t-butyl perbenzoate, di-t-butyl diperphthalate and 2,2-di - (t - butyl - peroxy) - butane, by heating at 25-95 DEG  C. until at least 60 per cent converversion has been effected and subsequently completing the polymerization at 100-150 DEG  C.  The polymerizable mixture may contain a plasticizer.  The aryl monomer may be styrene, vinyl naphthalene, o-, m-, or p-chlorostyrene, dichlorostyrenes, trichlorostyrenes, fluorostyrenes, vinyl chloronaphthalene, p-chloro-p-vinyl diphenyl, methyl styrenes, dimethyl styrenes, ethyl styrenes, isopropyl styrenes, vinyl methyl naphthalenes, divinyl benzenes, phenyl styrenes, phenethyl styrenes, tolyl styrenes, cyclohexyl styrenes, dicyano styrenes, trifluormethyl styrenes, cyanomethyl styrenes, methoxymethyl styrenes, or acetoxyethyl styrenes.  The other monomer may be vinyl chloride or fluoride; vinylidene chloride or fluoride; acrylic acid, methacrylic acid, chloroacrylic acid, beta-cyano-acrylic acid; methyl or ethyl acrylate or methacrylate, methyl chloroacrylate, fluorophenyl acrylate, methyl beta-cyano-acrylate; acrylamide, methacrylamide, chloroacrylamide, beta - cyano - acrylamide; acrylonitrile, methacrylonitrile, chloroacrylonitrile, fumaronitrile; methylene-malonic esters; acrolein, methacrolein; allyl methyl ketone, allyl ethyl ketone; allyl chloride; allyl methyl ether, allyl ethyl ether, methallyl ethyl ether, allyl phenyl ether; allyl acetate, allyl propionate, allyl acrylate, methallyl acrylate, diallyl phthalate, diallyl oxalate, diallyl succinate; diallyl ether, diallyl ketone, dimethallyl ketone; dimethyl or diethyl maleate or fumarate, di-isopropyl maleate; dimethyl or diethyl citraconate; divinyl ether, vinyl methyl ether, vinyl phenyl ether; divinyl ketone, vinyl methyl ketone, acrylophenone and mixtures.  Plasticizers mentioned are butyl and beta-butoxy-ethyl stearates, methyl and amyl oleates, cyclohexyl stearate, dicapyryl sebacate, dimethyl, dibutyl, and diamyl phthalates, dibenzyl maleate, betaphenoxyethyl benzoate, beta-(3-chloro-2-xenoxy) - ethyl levulinate, beta - ethoxyethyl - 2-chloro - phenoxy - acetate, beta - butoxyethyl phenoxy-acetate, chlorinated diphenyl ether, cyclohexyl chlorinated diphenyl ether, betaphenoxyethyl fumarate, 1,3-di-(4-t-butyl-phenoxy)-isobutane, ethyl lactate salicylate, diphenyl, polyisobutylene, alpha-methyl styrene polymers, dimers and trimers of styrene, chlorinated waxes, chlorinated diphenyl, ohlcrinated naphthalene, and 1,2 - bis - (4 - chlorophenyl) ethane.  Specified peroxides are benzoyl, chlorobenzoyl, bromobenzoyl, fluorobenzoyl, alkoxy-benzoyl, alkyl-benzoyl, phthaloyl and naphthoyl peroxides.  The polymerization in aqueous media may be effected in the presence of calcium hydroxy hexaphosphate, sodium oleate, or the sodium salt of sulphonated dodecyl benzene.  Specifications 604,544 and 690,124 are referred to.