GB678216A - Improvements in or relating to the polymerisation of vinyl-type compounds - Google Patents

Abstract

Polymers and copolymers of ethylenically unsaturated monomers are made by polymerizing in the presence of catalysts consisting of the organic per-esters of non-aromatic carboxylic acids containing at least one tertiary alkyl percarboxylic acid ester group, the carbonyl group of which is linked to another carbonyl group either directly or via only one carbon atom. The polymerization may be carried out in bulk, solution or emulsion in the presence or absence of emulsifying agents, in acid, neutral, but preferably alkaline media, using heat and/or light, in a batchwise or continuous manner, under atmospheric, superatmospheric or subatmospheric pressure, in the absence of oxygen or in an atmosphere of the monomer. Before or during emulsion polymerization various ingredients may be added such as emulsion stabilizers, e.g. polysaccharides, gum arabic, soluble starch, dextrine, plasticizers, e.g. dioctyl phthalate, and glycerol monoleate, lubricants, dyes, pigments and fillers. Specified catalysts are t-butyl beta-keto perpropionate or pervalerate, t-amyl beta-keto, gamma-ethyl percaproate, t-butyl monoperoxalate, t-hexyl monopermalonate, t-hexyl, monopermethylmalonate, O,O - tert - butyl O-methyl or O-ethyl monoperoxalate, O,O-tertamyl O-butyl monopermalonate, t-butyl diperoxalate, t-amyl dipermalonate, t-hexyl dipermethylmalonate, t-butyl methyl diperoxalate, t-butyl butyl dipermalonate, di-tert-butyl diperoxalate, and di-tert-amyl dipermethyl-malonate, di-t-butyl dipermalonate, di-t-butyl diperoxalate, di-t-butyl monopermalonate, di-t-butyl dipermethylmalonate, t-butyl beta-keto perbutyrate and mixtures. Specified monomers are butadiene-1,3, 2,3-dimethylbutadiene-1,3, butadiene-3,4-carbonate, piperylene, isoprene, chloroprene, styrene, alpha-methyl styrene, dichlorostyrene, 4-methyl- and 4-butyl styrene, vinyl naphthalene, vinyl phenol, acrylic and alpha-alkyl acrylic acids, methyl or propyl acrylate, methyl or butyl methacrylate, vinylidene chloride or bromide, vinyl chloride or bromide, acrylonitrile and methacrylonitrile, vinyl acetate, chloracetate, benzoate, valerate, or caproate, divinyl succinate, divinyl adipate, vinyl allyl phthalate, vinyl methallyl pimelate, vinyl methyl glutarate, vinyl acrylate or crotonate or methacrylate, vinyl ethyl or butyl or allyl ether, vinyl butyl or ethyl ketone, allyl acetate, allyl butyrate, diallyl phthalate, diallyl adipate, diallyl succinate, allyl chloride, methallyl chloride, allyl acrylate, allyl crotonate, methallyl methacrylate, and diethyl fumarate or maleate. The emulsifying agent may be sodium or potassium myristate, laurate, palmitate, oleate, stearate, rosinate or hydroabietate, sodium lauryl sulphate, potassium stearyl sulphate, sodium lauryl sulphonate, potassium stearyl sulphonate, sodium cetyl sulphonate, sulphonated mineral oil and ammonium salt thereof, lauryl amine hydrochloride and stearyl amine hydrobromide. During emulsion a mildly alkaline condition may be maintained by the addition of compounds such as trisodium phosphate, sodium carbonate, sodium bicarbonate, tetrasodium pyrophosphate, disodium-hydrogen phosphate or calcium carbonate. Specification 612,331 is referred to.