Homogeneous Reverse Atom Transfer Radical Polymerization of Styrene Initiated by Peroxides

The homogeneous reverse atom transfer radical polymerization (ATRP) of styrene was initiated by benzoyl peroxide (BPO) in the presence of CuBr or CuBr2 complexed by 4,4‘-di(5-nonyl)-2,2‘-bipyridine (dNbpy). In contrast to the successful reverse ATRP initiated by azobis(isobutyronitrile) (AIBN) and CuBr2/2dNbpy, no control of polymerization was observed for the BPO/CuBr2/2dNbpy system. However, controlled/“living” polymerization was observed when BPO was used together with CuBr/2dNbpy. The differences between the BPO and AIBN systems are ascribed to the electron transfer and the formation of copper benzoate species.