Preparation of polymide‐imides by direct polycondensation with triphenyl phosphite. V. Aliphatic‐aromatic polyamide‐imides based on N,N′‐bis(ω‐carboxyalkyl) benzophenone‐3,3′,4,4′‐tetracarboxylic diimides

Five diimide‐dicarboxylic acids were prepared from benzophenone‐3,3′,4,4′‐tetracarboxylic dianhydride and glycine, β‐analine, 4‐aminobutyric acid, 6‐aminocaproic acid, and 11‐aminoundecanoic acid. New aromatic‐aliphatic polyamide‐imides were prepared by the direct polycondensation of these diacids with aromatic diamines using triphenyl phosphite in N‐methyl‐2‐pyrrolidone (NMP)–Pyridine solution in the presence of calcium chloride. The resulting polymers were characterized by inherent viscosity, infrared spectra, elemental analyses, solubility, differential scanning calorimetry (DSC), thermogravimetry, and wideangle x‐ray diffraction measurements.