SYNTHESIS AND CHARACTERIZATION OF POLYAMIDES CONTAINING IMIDAZOLE - INTRAMOLECULAR HYDROGEN-BONDING AND CONSTITUTIONAL ISOMERISM

Polyamides derived from 1-methyl-4,5-imidazoledicarboxylic acid and al iphatic diamines such as hexamethylenediamine, neopentylenediamine, an d ethylenediamine are synthesized and characterized. The polymers have inherent viscosities up to 0.56 dL/g, are amorphous, have good therma l stability, and are soluble in a wide range of solvents. The amide pr oton of the carboxamide at the 5-position of the imidazole intramolecu larly hydrogen bonds to the carbonyl oxygen at the 4-position. There i s little or no evidence of intermolecular hydrogen bonding occurring i n the polyamides. The non symmetric diacid creates constitutional isom erism in the polymers. This isomerism can be detected at various level s, by NMR spectroscopy, in the polyamides depending on the diamine por tion and the solvent used.