研究了不同氧气浓度存在下CuBr/配体催化苯乙烯（St）的原子转移自由基聚合（ATRP）和CuBr2/配体催化St的自由基聚合。利用气相色谱跟踪单体转化率,利用凝胶渗透色谱测定聚合物分子量（-Mn,GPC）随聚合时间的变化。结果表明,在St的ATRP过程中,尽管聚苯乙烯分子量均同单体转化率成正比且维持窄分布,但氧气浓度越低,反应越快,同等转化率下聚合物的-Mn,GPC更低,引发效率更高。在直接以CuBr2/配体催化St的聚合时,CuBr2/四甲基乙二胺（TMEDA）可以顺利催化St的聚合,但是用CuBr2/2,2′-联吡啶,反应则不能发生。由此可知,在以上聚合过程中,TMEDA不仅起到了配体的作用,而且和CuBr2构成了氧化还原引发体系。
CuBr/ligand-catalyzed atom transfer radical polymerization （ATRP） in the presence of O2 and CuBr2/ ligand-catalyzed radical polymerization of styrene （St） were investigated. The monomer conversion and molecular weight （MW） were determined by gas chromatography and gel-permeation chromatography, respectively. The results show that in ATRP of St, although the MW of polystyrene increases in proportional to monomer conversion, and keeps narrow distribution, the presence of 02 will lower the reaction rate and the initiator efficiency. For the CuBr2/ligand-catalyzed radical polymerization, the CuBrz/tetramethylethylenediamine （ TMEDA ） successfully catalyzes polymerization of St, but CuBr2/2,2＇-bipyridine（bPy） fails. Thus, the following mechanism may work： TMEDA functions as a ligand and also constitutes redox system with CuBr2.
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