ABA triblock copolymers containing polyisoprene segments,such as polyisoprene b polystyrene b polyisoprene (PIP b PSt b PIP)and polyisoprene b poly(methyl methacrylate) b polyisoprene(PIP b PMMA b PIP),were prepared with macro iniferter technique.The macro iniferters (PSt CCDCM and PMMA CCDCM)bearing α and ω N,N diethyldithiocarbamyl (DC)groups were synthesized by bulk polymerization of St and MMA with diethyl 2,3 dicyano 2,3 di( p N,N diethyldithiocarbamylmethyl) phenylsuccinate (DDDCS) as a thermal iniferter.The block copolymerization of IP with PSt CCDCM or PMMA CCDCM was carried out under UV light irradiation.The block copolymers were characterized by 1H NMR,GPC and DSC analyses,and the polymerization proceeded as a living polymerization process.
Living" radical polymerization of methyl methacrylate was investigated using a new initiating system, i.e. DCDPS/FeCl 3/PPh 3, in which diethyl 2,3 dicyano 2,3 diphenyl succinate(DCDPS) is a hexa substituted ethane thermal iniferter. The polymerization mechanism belongs to a reverse ATRP process. The polymerization was closely controlled in bulk at 75 ℃, polymethyl methacrylate(PMMA) with a high molecular weight and quite narrow polydispersity ( M w/ M n=1 20—1 29) was obtained. End group analysis by 1H NMR spectroscopy shows that the resulting PMMA is ω functionalized by a chlorine atom, which is also confirmed by the chain extension reaction in the presence of CuCl/bipy catalyst via a conventional ATRP process. [WT5HZ]
Living radical polymerization of methyl methacrylate was investigated using a new initiation system, i. e. DCDPS/Fe(DC)3, in which diethyl 2,3-dicyano-2,3-diphenyl-succinate(DCDPS) is a hexa-substituted ethane thermal iniferter and ferric tri(diethyldithiocarbamate)(Fe(DC)3) is a ligand-free catalyst. The polymerization was successfully controlled in bulk at 95 ℃, PMMA with high molecular weight and quite narrow polydispersities(Mw/Mn=1.20～1.29) were obtained. End group analysis by 1H NMR spectroscopy shows that the resulting PMMA is ω-functionalized by a DC group.
