Reversible addition-fragmentation chain transfer (RAFT) polymerization of
N,
N-diethyl-2-methylene-3-butenamide (
DEA), which is a 1,3-butadiene derivative containing a diethylamide function, was carried out in chlorobenzene with using benzyl dithiobenzoate (
BDB) as a chain transfer agent. When
DEA was polymerized at 70°C using azobisisobutyronitrile (AIBN) as an initiator in the presence of
BDB, polymers of narrow molecular weight distribution (Mw/Mn<1.2) were obtained. The molecular weight increased proportionally with conversion, and the observed values were close to the calculated ones based on the molar ratio of monomer to
BDB. This indicates that the molecular weight of the polymer can be controlled by the molar ratio of monomer to chain transfer agent. Poly
DEA thus obtained contained
BDB fragment which was confirmed by MALDI-TOF-MS analysis. Block copolymerization with styrene was carried out using poly
DEA having
BDB fragment as macro chain transfer agent. Microstructure of poly
DEA was predominantly 1,4-sructure. Thus simultaneous control of the molecular weight and microstructure was achieved in the RAFT polymerization of
DEA.
Time dependence of molecular weight and its distribution in the RAFT polymerization of
DEA with using
AIBN and
BDB as an initiator and RAFT agent, respectively.
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