Studies on thermal degradation of epoxy resins by high-resolution pyrolysis-gas chromatography

Abstract

The optimum pyrolytic conditions for thermosetting epoxy resin samples were first empirically studied. On the basis of the optimized pyrolytic conditions, epoxy prepolymers and epoxy resin samples cured with and without curing agents, such as diamine and dicarboxylic acid anhydride, were studied using high-resolution pyrolysis-gas chromatography. In addition to some intact prepolymer molecules, various degradation products characteristic of the prepolymers, up to diglycidyl ether of bisphenol A, were detected on the pyrograms of the prepolymers. On the other hand, various phenols characteristic of the prepolymers and a variety of pyrolyzates characteristic of the reacted curing agents, including intact dicarboxylic acid anhydride, were observed on the programs of the cured resin samples. The potential of this technique for studying the curing process of the epoxy resins is discussed.