SYNTHESIS OF NEW PHOTORESPONSIVE POLYAMIDES CONTAINING NORBORNADIENE RESIDUES IN THE MAIN-CHAIN

New photoresponsive polyamides containing norbornadiene (NBD) residues in the main chain were synthesized in high yields by interfacial polycondensation between 2,5-norbornadiene-2,3-dicarboxylic acid dichloride (NBDC) and various primary or secondary diamines. The same polyamides were also obtained in high yields by direct polycondensation between 2,5-norbornadiene-2,3-dicarboxylic acid and various diamines using diphenyl (2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate and triethylamine as activating reagents. The degree of viscosity of the copolymers prepared by the reaction of NBDC and adipoyl chloride (ADC) with diamines increased with increasing ADC concentration, although the viscosities of homopolymers prepared by the reaction of NBDC with diamines were low. The photochemical properties of the resulting polyamides were examined in dichloromethane solution and in the film state. Polyamide 5 prepared with aromatic diamines showed higher photochemical reactivity than polyamides 1-4 prepared with aliphatic diamines both in dichloromethane solution and in the film state. Furthermore,it was also found that the rates of photochemical reaction of polyamide 1 sensitized with 5 mol % of Michler's ketone or 4-(N,N-dimethylamino)benzophenone were mostly the same as those of polyamide 5.