Synthesis of Polymers by Using Divalent Metal Salts of Mono(hydroxyethyl) Phthalate: Metal-Containing Three-Dimensional Polyesters from Metal Salts,Pyromellitic Dianhydride,and Epoxides

Syntheses of metal-containing three-dimensional polyesters were investigated by the reactions of divalent metal salts of mono(hydroxyethyl) phthalate-pyromellitic dianhydride-epoxide in DMF at 90° C. The metal carboxylate groups of these metal salts catalyzed the reactions. Systems with low metal salt content gelled during reaction. The yield of the products obtained by precipitating or washing with water increased with decreasing metal salt content in the feed. The products were metal-containing, three-dimensional polyesters containing ionic links; they were slightly yellow powdery materials. Hydroxyl values of the products were much higher than the values of acidity. Inherent viscosities (in DMF at 30° C) of the products obtained from the systems which did not gel were low, ranging from 0.031 to 0.083. The thermal stability of the products showed a tendency to increase with decreasing metal salt content in the feed.