Synthesis and characterization of new optically active and photolable poly (amide-imide)s from N,N′-(3,3′,4,4′-benzophenonetetracarboxylic)-3,3′,4,4′-diimido-di-L-methionine and different diamines

N,N′-(3,3′,4,4′-benzophenonetetracarboxylic)-3,3′,4,4′-diimido-di-L-methionine (3) was prepared from the reaction of 3,3′,4,4′-benzophenonetetracarboxylic-3,3′,4,4′-dianhydride (1) with L-methionine (2) in a solution of (glacial acetic acid/pyridine) at refluxing temperature. The phosphorylation polycondensation of the diimide-diacid monomer (3) with 1,3-phenylenediamine (4a), 1,4-phenylenediamine (4b), 2,6-diaminopyridine (4c), 3,5-diaminopyridine (4d), 4,4′-diaminobiphenyl (4e) and 4,4′-diaminodiphenylsulfone (4f) was carried out in N-methyl-2-pyrolidone (NMP). The resulting poly (amide-imide)s showed admirable moderate inherent viscosities (0.23–0.48 dl g-1), good thermal stability and improved optical activity. All of the above compounds were fully characterized by IR spectroscopy, elemental analysis and specific rotation. Some structural characterization and physical properties of these new poly (amide-imide)s are presented.