Living cationic polymerization of bisazobenzene-containing vinyl ether and synthesis of a graft copolymer by combination with ATRP

Abstract

Cationic polymerizable bisazobenzene-containing vinyl ether, which is being referred to as VEBiB, was synthesized and its cationic copolymerization with isobutyl vinyl ether (IBVE) using Et_1.5AlCl_1.5 as the catalyst, ethyl acetate as the added base, and 1-isobutoxyethyl acetate (IBEA) as the initiator was investigated at 0 °C. The copolymerization showed living features, which was confirmed by the linear increase of the molecular weight of the obtained copolymer with monomer conversion and relatively narrow molecular weight distribution. Furthermore, the resultant copolymer could be used as a macroinitiator for the atom transfer radical polymerization with activators generated by electron transfer (AGET ATRP) of methyl methacrylates (MMA) due to the presence of ATRP initiator moieties in the side chains of PVEBiB. A well defined graft copolymer was obtained and its photoresponsive behaviors were studied using UV-vis spectroscopy.