Step Transfer-Addition and Radical-Termination (START) Polymerization of ,-Unconjugated Dienes under Irradiation of Blue LED Light

摘要

A new polymerization method, termed as step transfer-addition and radical-termination, is developed for the step-growth radical polymerization of ,-unconjugated dienes under irradiation of visible light at room temperature (25 degrees C) for the first time. ,-Diiodoperfluoroalkane monomers (signified as A) are added onto ,-unconjugated dienes (signified as B) alternatively and efficiently with the generation of perfluorocarbon-containing alternating copolymers (AB)(n). Based on the combined analyses of polymerization kinetics and NMR spectra (H-1 and F-19), the mechanism of the novel polymerization method, including the side reaction, is proposed. This novel polymerization method provides a new strategy not only for the step-growth radical polymerization of ,-unconjugated dienes but also for the construction of high molecular weight perfluorocarbon-containing alternating copolymers.