SYNTHESIS AND CHARACTERIZATION OF NOVEL AROMATIC POLY(AMIDE-IMIDE)S WITH ALTERNATE (AMIDE-AMIDE) AND (IMIDE-IMIDE) SEQUENCES

Diamine amic acids were synthesized by reacting aromatic diamines with 3,3',4,4'-benzophenonetetracarboxylic dianhydride in dimethylacetamid e and were characterized by melting points, elemental analyses, IR, H- 1-NMR and HPLC. Poly(amide-amic acid)s were prepared by low temperatur e solution polycondensation of diamine amic acids with isophthaloyl ch loride in dimethylacetamide. Poly(amide-imide)s with alternate (amide- amide) and (imide-imide) sequences were obtained by cycloimidization o f poly(amide-amic acid)s with Et3N-Ac2O mixture in dimethylacetamide s olution. They were characterized by solubilities, inherent viscosities , IR and H-1-NMR. Thermal properties of the polymers were measured by differential scanning calorimetry and thermogravimetric analyses. (C) 1998 Elsevier Science Ltd. All rights reserved