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Preeyanuch Sangtrirutnugul Kritdikul Wised Purmpoon Maisopa Nisalak Trongsiriwat Pramuan Tangboriboonrat Vichai Reutrakul 《Polymer International》2014,63(10):1869-1874
The tripodal ‘click’ compound tris(4‐trimethylsilylmethyl‐1,2,3‐triazolylmethyl)amine (TTTA) was prepared and investigated as a ligand for copper‐catalysed single‐electron transfer living radical polymerization of methyl methacrylate (MMA). Bulk polymerizations catalysed by Cu0/CuBr2/TTTA with a molar ratio of [MMA]0/[ethyl‐2‐bromoisobutyrate]0/[CuBr2]0/[TTTA]0 = 200:2:1:1 and a 1.0 × 1.0 cm2 Cu0 sheet were fast and well controlled (76% conversion with Mw/Mn = 1.19 after 3.5 h). Greater amounts of added air generally gave slower polymerizations although Mw/Mn remained low (<1.3) even when the polymerization was carried out under aerobic conditions. Decreasing initial concentrations of the Cu0/CuBr2/TTTA catalyst system or polymerization temperatures also resulted in slower polymerizations and yielded polymers with broader dispersity. Kinetic studies in the temperature range 40–90 °C revealed an apparent activation energy of 22.6 kJ mol?1. © 2014 Society of Chemical Industry 相似文献
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Preeyanuch Sangtrirutnugul Purmpoon Maisopa Laksamee Chaicharoenwimolkul Atchariya Sunsin Ekasith Somsook Vichai Reutrakul 《应用聚合物科学杂志》2013,127(4):2757-2763
A series of tris(R‐methyltriazolylmethyl)amines [R = C6H5 ( 1 ), 4‐FC6H4 ( 2 ), 4‐MeOC6H4 ( 3 ), Fc ( 4 )] were prepared and used as ligands for catalytic ATRP of methyl methacrylate (MMA). Despite a lower activity, the CuBr/ 4 catalyst promoted relatively well controlled polymerization compared to CuBr/ 1 , as evidenced by narrower polydispersity indices. Meanwhile, no polymerization activity was observed with CuBr/ 2 and CuBr/ 3 under the catalytic conditions investigated. The CV measurements of CuBr2 complexes supported 1 and 4 in DMSO showed E1/2 values of –0.206 and –0.224 V, respectively, confirming the more electron‐rich nature of CuBr/ 4 . Although both CuBr/ 1 and CuBr/ 4 catalysts were only partially soluble in several organic solvents used, kinetic studies revealed a pseudo first order linear plot of ln[M]0/[M]t versus time. Addition of CuBr2 into the polymerization systems led to a decrease in polymer polydispersities and the observed rate constants (kobs). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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