GB836220A - Improvements in the polymerisation of unsaturated compounds - Google Patents

Abstract

Ethylenically - unsaturated compounds are polymerized or copolymerized using, as polymerization initiator, hydroxylamine-O-sulphonic acid or its derivatives from which it is readily split off, e.g. the sodium salt or potassium formaldoxime sulphonate. The unsaturated compound may be vinylidene chloride, vinyl chloride, acetate or propionate, acrylonitrile, styrene, acrylic acid or its salts or esters, e.g. methyl or ethyl acrylate, acrylamide, vinyl ethers, divinyl benzene, vinyl pyridine, C-vinylimidazole, C-vinylbenzimidazole, N-vinyl pyrrolidone, N-vinyl carbazole, N-vinyl imidazole, N-vinyl benzimidazole, vinyl sulphonic acid esters, maleic acid esters, e.g. diethyl maleate, maleic anhydride or methyl methacrylate or derivatives of the above, e.g. the quaternary ammonium salt of N-vinyl imidazole and dimethyl sulphate or dichlorbutane. There may be used in conjunction with the hydroxylamine-O-sulphonic acid initiator oxidizing agents and/or, reducing agents. The oxidizing agent may be benzoyl or cyclohexanone peroxide, cumene hydoperoxide, peracetic acid, hydrogen peroxide, persulphates, chromates or permanganates. The reducing agent may be sodium bisulphite, formamidine sulphinic acid, formaldehyde sodium sulphoxylate or a sulphite, hydrosulphite, sulphide, thiosulphate, mercaptan, or an amine. There may also be used in conjunction with the above initiator copper, iron, zinc or tin metals or their oxides and salts such as potassium pyrophosphate, potassium chromate, sodium dithionite, sodium ferrous or manganous sulphate, lead acetate, cuprous chloride, titanium trichloride or chromium or alkaline earth metal salts or complexes such as hexabenzoato - tri - ferri - monobenzoate. The polymerization may be carried out in aqueous or organic solution, e.g. in dimethyl formamide, bulk or emulsion, e.g. using an ethylene oxidesperm oil alcohol adduct as emulsifying agent, and within a specified pH range.