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α,α-二溴乙酸乙酯作双官能引发剂ABA型嵌段共聚物的合成

傅志峰;刘海涛;石艳;焦书科

  Ethylα,αdibromoacetate was confirmed to be a difunctional initiator for the atom transfer radical polymerization ofnbutyl acrylate by means of gel penetration chromatography. When the polymerization of nbutyl acrylate was carried out at different molar ratios of ethylα,αdibromoacetate and ethylαbromopropionate with CuBr/2,2′bipyridine as the catalyst, polymers with bimodal molecular weight distributions were obtained, consisting of two narrowly distributed fractions, one of which was of a molecular weight double the other. Poly(nbutyl acrylate) obtained with ethylα,αdibromoacetate as the difunctional initiator was further used as the macroinitiator for styrene and methyl methacrylate in the presence of CuBr/2,2′bipyridine respectively to prepare ABA triblock copolymers. It was found that high blocking efficiency was obtained for styrene. However, the polymer with bimodal molecular weight distribution was obtained for methyl methacrylate with a low molecular weight peak corresponding to that of poly(nbutyl acrylate) macroinitiator. If the blocking polymerization was conducted with CuCl/2,2′bipyridine as the catalyst to replace CuBr/2,2′bipyridine, a high blocking efficiency was also obtained.[WT5HZ]……   
[关键词]:原子转移自由基聚合;双官能引发剂;嵌段共聚物
[文献类型]:期刊
[文献出处]: 《高等学校化学学报2000年06期
[格式]:PDF原版; EPUB自适应版(需下载客户端)