Mechanistic study on photocuring of a methacrylates copolymer by benzophenones



The types of photochemical reactions that will occur in the photosensitive resin for optical devices, poly(methyl methacrylate-co-crotyl methacrylate) (PMMA–CMA) doped with meta-benzoylbenzophenone (BBP), were investigated. Oxetane formation, hydrogen abstraction followed by radical coupling, and pinacol formation were found to occur. The quantum yield for disappearance of benzophenone (BP) in the PMMA–CMA film was estimated as 0.68. The pendant crotyl group seems to be a major photoreaction site.