PHOTOCHEMICALLY ACTIVE POLYMERS CONTAINING PENDANT ETHYL PHENYLGLYOXYLATE

Photoreactions of acrylic polymers containing pendant ethyl phenylglyo xylate groups at different distances from the polymeric backbone have been studied. Hydrogen abstraction between pendant groups by an excite d triplet phenylglgoxylate carbonyl group from adjacent pendant groups is the primary process. The expected gamma-hydrogen abstraction withi n one pendant group (the Norrish type II reaction) is not observed. Th e radicals formed react with each other to form cross-linked structure s in the polymer. This effects solubility in various solvents which ch anges significantly after irradiation. The potential of the polymer as an imageable material has been evaluated.