Cobalt mediated radical polymerization of 4-bromo-2,6-dimethyl phenol and its copolymerization with poly(dimethyl siloxane) in the presence of Co(acac)2:DMF catalyst

Poly(phenylene oxide) was synthesized from 4-bromo-2,6-dimethylphenol (BDMP) in the presence of cobalt acetoacetonate (Co(acac)2) catalyst with dimethyl formamaide (DMF) ligand. The reaction was initiated with benzoyl peroxide at 60 ºC. BDMP reacted with poly(dimethyl siloxane) (PDMS) in a novel controlled copolymerization reaction within a good yield. The solid polymer indicated a narrow molecular weight distribution (PDI≈1.28). This monomer copolymerized further with styrene and methyl methacrylate, extending the scope of the controlled radical polymerization from the brominated dialkyl aromatic phenols to a number of various monomers. Synthesis of the polymers, copolymers, and block copolymers are considered new in preparing thermally stable block copolymers, with novel reactions to make new rotaxanes with a wide range of chemical compositions. Reactivity ratio for VAc and BDMP monomer pairs was calculated from Mayo-Lewis (rPDMS= 0. 293, rBDMP=0. 485) , Kelen-Todous (rPDMS= 0. 289, rBDMP=0. 476) and Finemann-Rose (rPDMS= 0. 299, rBDMP=0. 481).