Photoactive polytetrahydrofuran macroinimers were synthesized by the cationic polymerization of tetrahydrofuran initiated by the unsaturated oxocarbenium salt and subsequent termination by 2-picoline N-oxide. Macroinimers incorporating vinyl and pyridinium groups and methyl methacrylate were used in the grafting reaction in the presence of 2,2'-azobisisobutyronitrile as a thermal initiator. Side chain block copolymers were obtained by indirect photochemical polymerization of methyl methacrylate. Upon subjecting the pyridinium-ion-containing graft copolymer to UV irradiation in the presence of anthracene (photosensitizer) and methyl methacrylate, the polymerization of methyl methacrylate was initiated. (C) 1998 Elsevier Science Ltd. All rights reserved.