PREPARATION OF POLY(AMIDE-IMIDE)S DERIVED FROM BIPHENYLTETRACARBOXYLIC DIANHYDRIDES

Four new diimide-dicarboxylic acids (I-IV) were prepared by condensati on of s- or a-BPDA with para- or meta-aminobenzoic acid. A series of a romatic poly(amide-imide)s containing these diimide-dicarboxylic units was prepared by three methods: (1) acid chloride method, (2) tripheny lphosphite method, and (3) one-pot method. A typical polymer of the se ries is readily soluble in polar aprotic solvents such as N-methyl-2-p yrrolidone (NMP), dimethylsulfoxide (DMSO), and pyridine (py) and coul d be cast into tough and flexible films. These were characterized by i nherent viscosity, differential scanning calorimetry(DSC), and thermog ravimetric analysis (TGA) measurements. The glass transition temperatu res of these polymers were in the range of 220-290 degrees C, and the 5% weight loss temperatures were 450-500 degrees C. Films prepared by casting from polymer solutions exhibited good tensile properties. (C) 1997 John Wiley & Sons, Inc.