Organic polymer photochemistry

Abstract

Some fundamental characteristics of polymer photochemical reactions are shown and their differences with reactions of their model compounds are underlined. Successively are considered: i) photodegradation of methacrylic copolymers carrying photolabile acyl-O-α ketooxime side groups and degradation of polyethylenimines by H-abstraction by photoexcited benzophenone; ii) photoinitiation of block polymerization by photolysis of methylbenzoin ether incorporated in a condensation polymer and by selective photolysis of a heterofunctional initiator, e.g., oligoazoperoxides, and azo-di-t-butyl peresters. The advantages of the photochemical initiation with respect to corresponding thermal processes reside in its high selectivity and low reaction temperature; iii) photochemical electron donor-acceptor (EDA) interactions in copolymers of vinylbenzophenone (VB) and p-dimethylaminostyrene (DAS), and in terpolymers VB-DAS and methacrylic esters. The influence of crossed dyad concentration on absorption and emission spectra is underlined. Electron paramagnetic resonance (EPR)-measurements of radial concentration indicate a strong effect of the physical state of the matrix. © 1985 The Society of Polymer Science, Japan. All Rights Reserved.