Publication Details (including relevant citation information):
Massimo Benaglia, John Chiefari, Yen K. Chong, Graeme Moad, Ezio Rizzardo,San H. Thang; JACS, 2009, 131(20), 6914–6915
The polymerization of most monomers polymerizable by radical polymerization can be controlled by the RAFT process. However, it is usually required that the RAFT agent be selected according to the types of monomer being polymerized. Thus, RAFT agents (dithioesters, trithiocarbonates) suitable for controlling polymerization of the ‘more activated’ monomers (MAM, e.g. styrene, acrylates, methacrylates, etc.) tend to inhibit polymerizations of ‘less activated’ monomers (LAM, e.g. vinyl acetate, N-vinylpyrrolidone, etc.). Similarly RAFT agents suitable for polymerizations of ‘less activated’ monomers (xanthates, certain dithiocarbamates) tend to give little or poor control over polymerizations of MAMs. We now report a new class of “switchable” RAFT agents. Thus, N-(4-pyridinyl)-N-methyldithiocarbamates provide excellent control over polymerization of LAMs and after addition of one equivalent of a protic or Lewis acid they become effective in controlling polymerization of MAMs allowing the synthesis of polyMAM-block-polyLAM with narrow molecular weight distributions.
Address (URL): http://pubs.acs.org/doi/abs/10.1021/ja901955n