以季戊四醇为原料合成了2,2-二溴甲基-1,3-二溴丙烷（PEBr4）,并以此为引发剂,Cu0粉/三-（2-二甲氨基乙基）胺（Me6-TREN）为催化体系,在二甲亚砜（DMSO）中实现了丙烯酸甲酯（MA）的单电子转移活性自由基聚合（SET-LRP）,得到了星形PMA。采用1H-NMR对PMA结构进行表征确认并采用GPC测定了PMA的分子量及分子量分布,单体转化率为36.3%时聚合物的分子量为13300,-Mw/-Mn=1.40;考察了水、单体/催化剂（引发剂）配比对聚合反应的影响。结果表明,H2O含量增加到20%（体积分数）导致表观聚合速率常数（kappp）由0.0367 h-1增加到0.2785 h-1;增加催化剂及引发剂用量分别导致kappp增加。
The star-shaped PMA was synthesized by SET-LRP at 30 ℃ with DMSO as the solvent of polymerization,PEBr4 as the multifunctional initiator,Cu0 powder and Me6-TREN as catalytic system.The PMA prepared via SET-LRP was characterized by GPC and 1H-NMR to identify the polymerization mechanism,and the results show that polymer has the perfect functional chain ends and relatively low molecular weight distribution,indicating a controlled polymerization.The effects of water,catalyst and initiator on polymerization were studied;the results show that the H2O content in binary mixtures increases to 20%（volume fraction） led to the kappp increasing from 0.0367 h-1 to 0.2785 h-1.meanwhile the kappp increases in corresponding with increasing catalyst amount or initiator amount,in addition,the w/n of PMA decreases as the amount of H2O,catalyst and initiator increase.
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