New polyamides, polyimides, and a polyamide-imide containing ester linkages were prepared by the reaction of trimethylene glycol di-p-aminobenzoate with terephthaloyl chloride, isophthaloyl chloride, adipoyl chloride, pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, and trimellitoyl chloride. the low temperature solution and interfacial polymerization techniques were utilized to prepare the above-mentioned polymers. the polymers thus prepared were found to be soluble in solvents like DMAC and DMSO and had inherent viscosities in the 0.15-0.60 range. the polyimides prepared formed transparent and flexible films.