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以廉价配体五甲基二乙烯三胺（PMDETA）、溴化铜（CuBr2）和还原剂为催化体系，进行了甲基丙烯酸丁酯（BMA）的电子转移再生活化剂原子转移自由基聚合研究（ARGETATRP），考察了影响反应可控性的因素。实验结果表明，配体用量至少为催化剂量10倍（物质的量）以上，反应温度应在65℃～85℃：所得聚合物分子量分布较窄；还原剂刷量增加，反应速率变快，但分子量分布变宽；催化剂用量减少时，还原剂相对用量要增加；催化荆的最少用量取决于引发剂与催化剂的物质的量比，当引发剂和催化剂物质的量比小于1：0．02时，催化剂的用量能降到单体物质的量的5×10^-5。倍，仍保持可控聚合，所得聚合物分子量分布较窄为1．29。

Using inexpensive pentamethyldiethylene trianaine (PMDETA) as a ligand, CuBr2 as a catalyst, Sn(EH)2 as a reducing agent, activator regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP) of butyl methacrylate was studied. The results show that polymerization is well controlled with the amount of ligand 10 times higher than that of the catalyst. The reaction temperature should be in the range of 65℃ to 85℃. The reaction rate is increased with the increasing amount of reducing agent, but the molecular weight distribution of poly(butyl methacrylate) becomes wider. With the decreasing amount of the catalyst, relative amount of reducing agent should be increased. The smallest amount of the catalyst required in the polymerization depended on the ratio of n ( initiator) /n (catalyst). When the ratio of n ( initiator) /n (catalyst) is less than 1 : 0.02, the butyl methacrylate (BMA) polymerization with copper catalyst level as low as 5 × 10^-5 of the mole of monomer exh, ibits controlled/living polymerization characteristics, and the degree of polymerization of 400 and the polydispersity index of 1.29 are obtained.