The termination reaction in radical polymerizations. Polymerizations of methyl methacrylate and styrene at 25
The termination reaction in radical polymerizations. Polymerizations of methyl methacrylate and styrene at 25
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自由基聚合中的终止反应。
DOI：
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发表时间：
1954
期刊：
影响因子：
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通讯作者：
R. Taylor
中科院分区：
文献类型：
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作者：
J. C. Bevington;H. Melville;R. Taylor
以C14标记的α，α′-偶氮-双异丁腈为引发剂，在25°温度下进行了苯乙烯和甲基丙烯酸甲酯的聚合。通过渗透法测定聚合物的平均分子量，通过气体计数测定聚合物和引发剂的比活度，确定了每个聚合物分子的引发剂片段数。聚苯乙烯自由基在25°c时结合，而聚甲基丙烯酸甲酯自由基在此温度下歧化的发生频率约为结合的两倍。
Styrene and methyl methacrylate have been polymerized at 25° using α,α′-azo-bis-isobutyronitrile labeled with C14 as initiator. The numbers of initiator fragments per polymer molecule have been determined by measurements of the average molecular weights of the polymers by osmometry and the specific activities of the polymers and the initiator by gas counting. It is found that polystyrene radicals combine at 25° and that for polymethyl methacrylate radicals at this temperature disproportionation occurs about twice as frequently as combination.