Synthesis and characterization of new optically active copoly(amid-imide)s based on N-phthalimido-l-aspartic acid and aromatic diamines

In this article, six new optically active copoly(amide-imide)s (10a-f) were synthesized through the direct polycondensation reaction of N-phthalimido-l-aspartic acid (4) with 1,5-diamino naphthalene (8), 3,4-diamino benzophenone (9) in the presence of therphthalic acid (7), fumaric acid (6) and adipic acid (5) as a second diacid in a medium consisting of N-methyl-2-pyrrolidone, triphenyl phosphite, calcium chloride and pyridine. The resulting copolymers were fully characterized by means of FT-IR spectroscopy, elemental analyses, inherent viscosity, solubility tests and UV-vis spectroscopy. Thermal properties of resulting copolymers (10a-c) containing three different second diacid in the main chain were compared by using TGA and DTG thermograms.