NEW POLY(AMIDE-IMIDE) SYNTHESES .12. PREPARATION AND PROPERTIES OF POLY(AMIDE-IMIDE)S BASED ON THE DIIMIDE-DIACID CONDENSED FROM 9,9-BIS[4-(4-AMINOPHENOXY)PHENYL] FLUORENE AND TRIMELLITIC ANHYDRIDE

A dicarboxylic acid (I) was prepared from the condensation of 9,9-bis[4- (4-aminophenoxy) phenyl]fluorene and trimellitic anhydride. A new family of poly(amide-imide)s having inherent viscosities of 0.75-1.04 dL/g was prepared by the triphenyl phosphite activated polycondensation from the diimide-diacid I with various aromatic diamines in a medium consisting of N-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All the soluble poly(amide-imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 262-325-degrees-C and the 10% weight loss temperatures were above 525-degrees-C in air. (C) 1994 John Wiley & Sons, Inc.