Mechanism and kinetics of dithiobenzoate-mediated raft polymerization- status of the dilemma

Dithiobenzoates are among the most popular agents for reversible addition-fragmentation chain transfer (RAFT) polymerization. This is attributed to the better control over molecular weight and end-group fidelity found in RAFT polymerization of methacrylates and methacrylamides. However, in polymerization of styrenes, acrylates, and acrylamides, their use has diminished, mainly in favour of trithiocarbonates, because of issues with retardation, as well as hydrolytic and thermal instability. This paper critically assesses developments in understanding the mechanism and kinetics of dithiobenzoate- mediated RAFT polymerization from 2006 to 2013, with specific reference to the choice of reagents, polymerization conditions, side reactions, and factors leading to retardation.