Six new dicarboxylic acids 3a-f were synthesized by the reaction of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) 1 with L-amino acids 2a-f in a solution of glacial acetic acid/pyridine (Py) at refluxing temperature. Then six new optically active poly(amide-imide)s (PAI)s with good inherent viscosities were synthesized by direct polycondensation reaction of [N,N'-(4,4'-diphtaloyl)-bis-L-amino diacid]s with 1,2-bis[4,4'-aminophenoxy] ethane (APE) 4 in a medium of N-methyl-2-pyrrolidone (NMP)/ triphenyl phosphite (TPP)/ calcium chloride (CaCl2)/pyridine. Not only PAIs are optically active but also soluble in various organic solvents. These resulting new polymers can be used in column chromatography for the separation of enantiomeric mixtures. The resulted polymers were fully characterized by means of FTIR, 1H-NMR spectroscopy, elemental analyses, inherent viscosity, specific rotation, solubility tests and UV-Vis spectroscopy. Also thermal properties of the PAIs 3a-fwere investigated using thermal gravimetric analysis (TGA).
