QUENCHING BENZOPHENONE PHOSPHORESCENCE IN SOLUTION BY COPOLYMERS CONTAINING VARYING AMOUNTS OF NAPHTHALENE GROUPS

Phosphorescence decay measurements were made on samples of 4-(methoxycarbonyl)ben-zophenone (1) in acetone solution in the presence of a series of copolymers of methyl methacrylate and 1-naphthylmethyl methacrylate. The data were used to obtain the rate constants feoba <2) for triplet quenching by the naphthalene [N] groups in the polymer. The data fit a model where diffusion of photoexcited 1 into the polymer coil is followed by a competition between reaction with the Ν groups and diffusion back into the bulk solution. The model accommodates the rate changes observed with changes in the N-group content of the copolymers. © 1990, American Chemical Society. All rights reserved.