Synthesis and characterization of novel organosoluble polyesters based on a DIOL with azaquinoxaline ring

A series of new polyesters were synthesized by polycondensation of aliphatic and aromatic dicarboxylic dichlorides with a novel quinoxaline diol, 2,3-bis (4-hydroxy phenyl)-5-azaquinoxaline (DIOL). The DIOL was synthesized by reacting 4,4'-dihydroxy benzil with 2, 3-diaminopyridine (yield: 85%), and characterized by FTIR and H-MAR spectra. All polyesters showed good solubility in most aprotic polar solvents such as NMP (N-methylpyrrolidone), DMF (dimethylformamide), DMSO (dimethylsulfoxide), DMAc (dimethylacetamide), HMPA (hexamethylenephosphoramide), and Py (pyridine). The inherent viscosity of polyesters was obtained in the range of 1.1-1.22 dL/mg. The glass transition temperatures of the polyesters were in the range of 200-280 degrees C, as determined by DSC. The initial decomposition temperatures of the polyesters were above 300 degrees C and the char yield at 750 degrees C ranged from 30 to 60% under nitrogen atmosphere. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 3458-3463, 2009