GB855025A - Improvements in and relating to polymerisable epoxide compositions - Google Patents

Abstract

A polymerizable composition comprises o, m or p-divinyl benzene dioxide and a polycarboxylic acid anhydride in an amount having 0,2 to 3 carboxyl equivalents per epoxy group; a polycarboxylic acid compound may also be present in amount having up to 1 carboxyl group per epoxy group, the total number not exceeding 3 and the acid always providing fewer carboxyl equivalents than the anhydride. The compositions are converted to hard, infusible resins by heating to 25 to 250 DEG C., if desired in the presence of catalysts. The polycarboxylic anhydrides may be of the formula XCO.O.CO, where X is 2 or more carbon atoms connected by single or double bonds and which may contain hydroxyl, nitro, chloro, iodo, bromo, and cyclic groups, as well as interconnecting oxydicarbonyl groups. Mixtures of anhydrides may be used. Many examples are given. The poly carboxylic acids are of the same classes and the acid compounds include poylhydric alcohol esters which contain more than one carboxyl group per molecule. The catalysts include mineral acids, sulphuric acids, metal halide Lewis acids, alkali metal hydroxides and amines, including aminophenols. They may be added as solutions in organic solvents. The uncured or partially cured compositions may be dissolved in solvents, e.g. xylene, methyl isobutyl ketone, butyl, ethyl and amyl acetates and toluene, particularly for applying surface coatings which are subsequently heat cured. In the examples, the dioxides are mixtures of the three isomers containing ethyl styrene oxide as main impurity. The hardeners are phthalic, succinic, glutonic, polyadipic and chlorendic anhydrides, mixtures of phthalic anhydric and sebacic acid, maleic anhydride and adipic acid, polyadipic anhydride and maleic acid, and of glutaric acid and the adduct of 1 mol of glycerol with 3 mols of succinic anhydride.