EPOXY RESIN, PROCESS FOR ITS PRODUCTION AND PROCESS FOR PRODUCING EPOXY FOAM.

摘要

This improved epoxy resin is represented by general formula (I) where R1 is H or an alkyl gp.; R2 and R3 are H, low-number C alkyl gp. or phenyl gp., independently; R2 and R3 can combine with each other to form a ring contg. a common carbon atom; X is a low-number C alkyl gp. or halogen atom; m is a number representing the number of substits. except H and lies between 0 and 4; n is 0-5. R1 is pref. H. R2 and R3 are pref. CH3 gps.; m is pref. zero. The epoxy resin is produced by the reaction of an oligocarbonate with an epihalohydrin followed by a ring-closure reaction, and removal of the hydrogen halide by the addn. of alkali. The epoxy foam is produced by reacting, at 120-240 deg.C in the presence of a catalyst, polyepoxy having two or more epoxy gps. with a carbonate oligomer having phenol-type hydroxy gps. at its ends. The polyepoxy cpds. are bisphenol A, tetrabromobisphenol A, polyphenol gps., hydroquinone, phthalic acid, etc.