GB755183A - Improvements in and relating to the polymerization of unsaturated compounds - Google Patents

Abstract

Monomeric ethylenically unsaturated organic compounds are polymerized in an aqueous medium at a pH of less than 6 and in the absence of oxygen or of peroxy compounds, the aqueous medium containing an initiator combination comprising in the aqueous phase under the conditions of polymerization: (a) at least 0.6 millimol., per litre of water, of an oxidizable anion consisting of one or more bisulphites or acetone-addition products of bisulphites; (b) at least 0.123 millimol., per litre of water, of trivalent iron; and (c) at least 0.6 equivalent, per mol. of trivalent iron, of an anion consisting of one or more of the following: fluoride, sulphate, thiocyanate, citrate, oxalate, phosphate, metaphosphate, pyrophosphate, tripolyphosphate, acetate or gluconate. The monomers may be one or more of ethylene, propylene, isobutylene, ethyl acrylate, ethyl, butyl, octadecyl, cyclohexyl, methoxymethyl, beta-diethylaminoethyl or chloroethyl methacrylate, acrylonitrile, methacrylic acid or anhydride, alpha-chloroacrylic acid, vinyl chloride, fluoride, acetate, propionate, stearate, laurate, or chloroacetate, vinylidene chloride, fluoride or fluorochloride, styrene, para-chloro styrene, vinyl naphthalene, vinyl pyridine, methyl vinyl ketone, vinyl ethyl ether, vinyl isobutyl ether, tetrafluoroethylene, trifluoromonochloroethylene, trifluoroethylene, 1,1 - dichloro - 2,2 - difluoroethylene, butadiene, 2 - chloro, 2 - fluoro - or 2 - phenoxy-butadiene, ethylene glycol, diethylene glycol, triethylene glycol or tetraethylene glycol dimethacrylate, diethylene glycol or decamethylene glycol diacrylate; glyceryl triacrylate, allyl methacrylate, methallyl methacrylate, crotyl acrylate, diallyl maleate, carbonate, adipate, fumarate or phthalate, divinyl succinate or adipate, divinyl benzene, hexafluoropropylene, octafluoroisobutylene, perfluoroheptane-1, maleic anhydride or dimethyl maleate. The trivalent iron (b) may be present in the form of a salt of an anion (c) such as ferric fluoride, sulphate, thiocyanate, oxalate or citrophosphate or ferric ammonium citrate. The aqueous reaction medium may contain acidic buffers such as acid sodium phosphate or sodium hydrogen sulphate and dispersing or emulsifying agents such as sodium alkyl sulphates, long chain alkyl aryl polyether alcohols, sodium isopropyl naphthalene sulphonate, fatty acid soaps, ionizable fluoroalkyl compounds as described in Specification 689,400, or a stabilizing agent for the polymer dispersion such as cetane, white mineral oil or paraffin wax as described in Specification 673,443. The process of the invention may be modified to produce telomers in the presence of a chain-transfer agent such as carbon tetrachloride, chloroform, methanol, ethanol, isopropanol, isobutyric acid, methyl propionate or dioxolane. Reference has been directed by the Comptroller to Specification 636,232.