Reverse atom transfer radical polymerization of styrene with copper-based catalyst

"Living"/controlled radical polymerization of styrene was carried out with diethyl 2,3-dicyano-2,3-diphenylsuccinate (DCDPS)/CuCl2/bipyridine (bipy) i nitiation system at 120 degreesC. The molecular weights of resultant PSt in creased with the monomer conversion and the polydispersities were in the ra nge of 1.37 similar to1.52. A linear ln([M](o)/[M]) versus time plot was al so obtained indicating the constant concentration of growing radicals durin g the polymerization with this initiation system. End group analysis by H-1 -NMR spectroscopic studies showed that the end groups of the polymer obtain ed is omega -functionalized by a chlorine group from the catalyst and alpha -functionalized by a (carbethoxy-cyano-phenyl)methyl group from the fragme nts of the initiator. Having CI atom at the chain end, the PSt obtained can be used as a macroinitiator to promote a chain-extension reaction with fre sh St and block copolymerization reaction with a second monomer, such as me thyl methacrylate, in the presence of CuCl/bipy catalyst via a conventional ATRP process.