Photocrosslinking of Polyamides Containing α-Diketone Linkage in the Main Chain

Abstract

Copolyamides containing α-diketone linkages were prepared from adipoyl chloride, 4,4′-dichloroformylbenzil, and hexamethylenedi-amine. Three polycondensation methods (unstirred interfacial, stirred interfacial, and solution method) were examined. The unstirred interfacial method gave soluble high molecular weight polymers. The copolymer composition was generally equal to that of the monomer feed. The content of the α-diketone linkage was varied from 5 to 20 mol%. The UV-induced gel formation was studied on films of copolyamides containing more than 10 mol% of the α-diketone linkage. The gel fraction, degree of gel swelling, changes in the IR spectrum, and Charlesby-Pinner' plots were examined. The photochemical reactions in the film are discussed.