Disproportionation or Combination? The Termination of Acrylate Radicals in ATRP
Disproportionation or Combination? The Termination of Acrylate Radicals in ATRP
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DOI：
10.1021/acs.macromol.7b01552
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发表时间：
2017-10
期刊：
影响因子：
5.5
通讯作者：
Thomas G Ribelli;Kyle F. Augustine;Marco Fantin;Pawel Krys;R. Poli;K. Matyjaszewski
中科院分区：
文献类型：
--
作者：
Thomas G Ribelli;Kyle F. Augustine;Marco Fantin;Pawel Krys;R. Poli;K. Matyjaszewski
在原子转移自由基聚合（ATRP）中丙烯酸酯自由基的终止可以包括常规的双分子自由基终止（RT）或催化自由基终止（CRT）。这些过程进行了研究，使用聚（丙烯酸甲酯）-Br大分子引发剂在不同的初始条件下调整，以改变RT/CRT的比例。通过尺寸排阻色谱法（SEC）分析在不存在单体的情况下由[CuI（L）]+（L =三[2-（二甲基氨基）乙基]胺（Me 6 TREN）、三（2-吡啶基甲基）胺（TPMA）或三（3，5-二甲基-4-甲氧基-2-吡啶基甲基）胺（TPMA*3））的卤代烷链端活化获得的聚合物。RT-促进条件导致肩的增加与双分子量（MW）相对于大分子引发剂的分布，表明RT发生主要是通过自由基组合。相反，当CRT被促进时，大分子引发剂分布没有改变，表明类似于抑制的途径。T的终止反应。
The termination of acrylate radicals in atom transfer radical polymerization (ATRP) can involve either conventional bimolecular radical termination (RT) or catalytic radical termination (CRT). These processes were investigated using a poly(methyl acrylate)–Br macroinitiator under different initial conditions tuned to change the RT/CRT ratio. The polymers, obtained from alkyl halide chain-end activation by [CuI(L)]+ (L = tris[2-(dimethylamino)ethyl]amine (Me6TREN), tris(2-pyridylmethyl)amine (TPMA), or tris(3,5-dimethyl-4-methoxy-2-pyridylmethyl)amine (TPMA*3)) in the absence of monomer, were analyzed by size exclusion chromatography (SEC). RT-promoting conditions resulted in the increase of a shoulder with double molecular weight (MW) relative to the macroinitiator distribution, indicating that RT occurred predominantly via radical combination. Conversely, when CRT was promoted, the macroinitiator distribution did not shift, indicating a disproportionation-like pathway. The termination reactions for the T...