CHI-HOW PENGScricco J.Li S.Fryd M.Wayland, Bradford B.Bradford B.Wayland2022-10-272022-10-272008https://www.scopus.com/inward/record.uri?eid=2-s2.0-42449110723&doi=10.1021%2fma702500b&partnerID=40&md5=40019ffdd979bb4b655e3edaa33897b2https://scholars.lib.ntu.edu.tw/handle/123456789/624032Vinyl acetate polymerization initiated by azo radical sources in the presence of cobalt(II) tetramesitylporphyrin ((TMP)CoII) shows an induction period followed by an organo-cobalt mediated living radical polymerization (LRP). The induction period corresponds to converting (TMP)CoII to an organo-cobalt porphyrin derivative (organo-Co(TMP)). Living character at low vinyl acetate conversion is demonstrated by a linear increase in molecular weight with conversion, relatively low polydispersity homopolymers, and formation of block copolymers with methyl acrylate ((TMP)Co-PVAc-b-PMA). Deviations from ideal LRP occur by radical termination and chain transfer events at moderate conversion of vinyl acetate (VAc). Mechanistic studies demonstrate that the VAc radical polymerization is controlled by a degenerative transfer mechanism that utilizes organo-cobalt complexes as the transfer agent. Kinetic studies are utilized in comparing radical polymerization of vinyl acetate and methyl acrylate that are mediated by organo-cobalt complexes. ? 2008 American Chemical Society.Living radical polymerization (LRP);Vinyl acetate;Free radical polymerization;Living polymerization;Vinyl resinsjournal article10.1021/ma702500b2-s2.0-42449110723