GB729883A - Improvements in or relating to copolymerizable compositions - Google Patents

Abstract

A copolymerizable composition comprises (1) a polyglycidyl ester of a polycarboxylic acid, (2) an a ,b -unsaturated polycarboxylic acid or anhydride and (3) styrene or a derivative. In a modification ingredients (1) and (2) may be partially polymerized. The esters may be derived from phthalic, oxalic, malonic, succinic, glutaric, sebacic, adipic, pimelic, suberic, azelaic, tricarballylic, citric, tartaric, malic, maleic, fumaric, aconitic and itaconic acids (see Group IV (b)), and ingredient (2) may be maleic, fumaric, aconitic or itaconic acid. Styrenes specified are styrene, a -methyl-, a -ethyl-, a -chloro-, o-methyl-, m-propyl-, p-ethyl-, o-, m- and p-chloro-, 2,4-dimethyl-, 2,5-dimethyl-, 3,4-diethyl-, 2,5-dichloro- and 3,5-dichlorostyrenes and mixtures. The polymerization may be carried out with heating alone (example 1) but is preferably effected in the presence of a catalyst such as t.-butyl hydroperoxide or di-t.-butyl- or methyl ethyl ketone-peroxide. In examples the curing is carried out in two stages and examples 2 and 3 include as a further ingredient a polyester derived from maleic and phthalic anhydrides, propylene glycol and pentaerythritol. The products are tough and of low shrinkage.ALSO:Polyglycidyl esters of polycarboxylic acids are prepared by reaction of reactive halohydrins, such as epichlorohydrin, epibromohydrin, epiiodohydrin and epifluorohydrin, with alkali or alkaline-earth salts of the polycarboxylic acids. In particular dipotassium phthalate and epichlorohydrin are reacted at 105-110 DEG C. with a quaternary ammonium salt as catalyst. The potassium chloride produced and excess epichlorohydrin are removed to give diglycidyl phthalate which is purified by vacuum distillation. Other polycarboxylic acids specified are oxalic, malonic, succinic, glutaric, sebacic, adipic, pimelic, suberic, azelaic, tricarballylic, citric, tartaric, malic, maleic, fumaric, aconitic and itaconic. The polyglycidyl esters may be polymerized with a ,b -unsaturated polycarboxylic acids and styrene or its derivatives (see Group IV (a)).