Synthesis of thermotropic liquid crystal polyimide and its properties

Abstract Thermotropic liquid crystal polyimide which has neither an ester linkage nor a carbonate linkage was prepared by the polymerization of 1,2,4,5‐benzenetetracarboxylic dianhydride (PMDA) and 1,3‐bis[4‐(4′‐aminophenoxy)cumyl)]benzene (BACB). This polyimide shows the liquid crystal phase at 549‐593 K. Mixing this liquid crystal polyimide or copolymerizing BACB decreases the melt viscosity of the thermoplastic polyimide (Aurum). © 1994 John Wiley & Sons, Inc.