POLYMERIC PHOTOINITIATORS AS A TOOL FOR CLARIFYING MECHANISTIC ASPECTS OF FREE-RADICAL POLYMERIZATION

Polymeric photoinitiators, based on side-chain benzoin methyl ether mo ieties differently anchored to the backbone, have been designed and ap plied to the UV cure of acrylic formulations for clarifying the role p layed by benzoyl and alpha-alkoxybenzyl primary radicals in the polyme rization process. Kinetic data on the photocuring processes, in the pr esence of the above polymeric systems, as compared with those obtained by using the corresponding low-molecular-weight structural models, ar e presented and interpreted in terms of different reactivity of the tw o types of primary radicals towards initiation and termination steps o f the polymerization process.