GB801795A - Improvements in or relating to copolymerisation - Google Patents

Abstract

Unsaturated polyesters are copolymerized with unsaturated monomers, e.g. styrene, vinyl acetate and methyl methacrylate, in the presence of a cobalt compound selected from cobalt compounds of tautomerically reacting keto-enol compounds, cobalt carbonyl, cobalt alcoholates and cobalt salts of alkoxo acids, in amount sufficient to inhibit surface tackiness in the resulting polymer. Specified cobalt compounds are those of ethyl acetoacetate, formyl acetone, acetyl acetone and diethyl malonate, cobalt butylate and the cobalt salt of the reaction product of aluminium butylate and butyl alcohol. The alcoholates and alkoxo salts are preferably stabilized by reacting with tautomerically reacting keto-enol compounds, e.g. those listed above. The unsaturated polyesters may be prepared from maleic, fumaric, muconic, phthalic, succinic, adipic, sebacic and suberic acids and anhydrides and ethylene glycol, polyethylene glycols, propylene glycol, trimethylene glycol, 1:2-, 1:3-, 2:3- and 1:4-butanediol and 1:4-butenediol, optionally together with glycerol and trimethylolpropane, at least one of the components being unsaturated. Pigments, filters and extenders may be added and polymerization effected in the presence of a catalyst, e.g. benzoyl peroxide, to give castings and coatings.