CROSS-LINKING OF BISEPOXIDE WITH DIVALENT METAL-SALTS OF P-AMINOBENZOIC ACID AND DIAMINE

Cross-linking of bisepoxide with divalent metal salts of p-aminobenzoic acid and 4,4'-diaminodiphenylmethane (4,4'-methylenedianiline) was investigated. As the bisepoxide, bisphenol A diglycidyl ether was used. Mg and Ca were used as the divalent metal. The metal salts showed catalytic activities for the cross-linking reaction and also for etherification of epoxy groups. In this case, the salt containing Ca with the lower electronegativity exhibited higher catalytic activities than that containing Mg. Hence, the cross-linking reaction was supposed to proceed via an ionic mechanism. As for the physical properties of the cured resins, compressive strength was higher in the metal-containing cured resins than in the resin without metal. Heat-distortion temperature showed a tendency to decrease with increase in the metal content. However, glass transition temperature determined by dynamic mechanical properties were not influenced by the metal content. The metal-containing cured resins exhibited low weight gain and changes in dimension and external appearance against boiling water. In addition, thermal decomposition was accelerated by the incorporated metal.