制备了铜-聚乙烯基咪唑(Cu(II)-PVI)络合物，用于催化水介质中2,6-二甲基苯酚(DMP)的氧化聚合，与传统催化剂Cu(II)-EDTA络合物相比，其催化效率约提高十倍。为探究Cu(II)-PVI络合物催化效率提高的原因，采用N,N’-亚甲撑-二(丙烯酰胺)作为交联剂与 N-乙烯基咪唑共聚合制备了 PVI 水凝胶。采用紫外可见吸收光谱研究了PVI水凝胶对DMP的吸附量随时间的变化，发现水溶液中DMP的浓度先随时间延长而降低，而PVI水凝胶中DMP的浓度则随时间延长而增加，最后达到平衡，说明PVI对反应底物DMP有浓缩效应。认为Cu(II)-PVI络合物催化水介质中DMP氧化聚合反应时，其催化效率的提高归结为PVI微团对催化剂和反应底物的浓缩效应。%Cu(II)-Poly(N-vinylimidazole) complex (Cu(II)-PVI) was synthesized and employed to catalyze the oxidative polymerization of 2,6-dimethylphenyl (DMP) in water. Compared with the conventional Cu(II)-EDTA catalyst, the Cu(II)-PVI complex catalyst shows an enhancement in the catalytic efficiency, which is nearly ten times higher than that of Cu(II)-EDTA complex. In order to elucidate the reason of the high catalytic efficiency of Cu(II)-PVI complex, N,N’-methylenebisacrylamide was used as a crosslinking agent and PVI hydrogel was prepared by radical copolymerization of N-vinylimidazole and N,N’-methylenebisacrylamide. UV-vis spectrophotometer was used to monitor the change of the adsorption of DMP in PVI hydrogel with time. It was found that DMP concentration in water firstly decreases with the increase of time, while DMP concentration in PVI hydrogel increases with time and finally maintains an equilibrium, which confirms the concentration effect of PVI for DMP. The high catalytic efficiency of Cu(II)-PVI complex can be ascribed to the concentration effect of PVI for both substrate and catalyst during the oxidative polymerization of DMP in water.
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