The development of Cu(0)/TREN/CuBr2-catalyzed SET-LRP of VC initiated with CHBr3 in DMSO at 25 degrees C is reported. The use of CuBr2 additive allows for the first LRP of low molecular weight VC (target DP = 100), as well as lower Cu powder loading levels, improved I-eff and control in the synthesis of higher molecular VC, targeted degree of polymerization = 350, 700, 1,000, 1,400. H-1 NMR and HSQC confirm the bifunctionality of CHBr3 as an initiator and suggest that deleterious side-reactions such as the formation of allylic chlorides occur primarily at the onset of the reaction. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4130-4140, 2009