Synthesis and characterization of new aromatic poly(amide-imide)s based on 4-aryl-2,6-bis(4-trimellitimidophenyl) pyridines

New diimide-dicarboxylic acids, ie 4-phenyl-2,6-bis(4-trimellitimidophenyl)pyridine and 4-p-biphenyl-2,6-bis-(.4-trimellitimidophenyl)pyridine, were synthesized by the condensation reaction of 4-phenyl-2,6-bis(4-aminophenyl)pyridine and 4-p-biphenyl-2,6-bis(4-aminophenyl)pyridine with trimellitic anhydride in glacial acetic acid or dimethylformamide. The monomers were fully characterized by FT-IR and NMR spectroscopies, and elemental analyses. A series of novel poly(amide-imide)s with inherent viscosities of 0.68-0.87 dl g(-1) was prepared from the two diimide-diacids with various aromatic diamines by direct polycondensation. The poly(amide-imide)s were characterized by FT-IR and NMR spectroscopies. The lambda(max) data for the resulting poly(amide-imide)s were in the range of 260-292nm. These polymers exhibited good solubilities in polar aprotic solvents. The 10% weight loss temperatures are above 485degreesC under a nitrogen atmosphere. (C) 2004 Society of Chemical Industry