A series of polymers formed from diesterdianhydrides of arylene-di(benzene-5-estro-1,2-dicarboxylic) anhydride type and tetraamines, 3,3＇diaminobenzidine acid 3,3＇,4,4＇tetraaminodiphenyl ether, has been synthesized using one-step high temperature polycondensation in m-cresol at 180 degrees C. The relation between polymer reduced viscosity and reaction time was studied and structures of the polymers were detected by FTi.r. spectroscopy.