High molecular weight (MW), 3-arm star poly(methyl methacrylate) (PMMA) with a narrow MW distribution (M _n =570,000 g/mol, PDI=1.36) was successfully synthesized by activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP). The polymerization was carried out with a trifunctional initiator/CuBr₂/N,N,N′,N′,N′-pentamethyldiethylenetriamine (PMDETA) initiator/catalyst system in the presence of a tin(II) 2-ethylhexanoate [Sn(EH)₂] reducing agent at 90 °C. The concentration of the copper catalyst was as low as 30 ppm, and a high initiation efficiency of the initiating sites was obtained. The chain-end functionality of the high MW, 3-arm star PMMA was confirmed by a chain extension experiment with styrene via ARGET ATRP, using the same catalyst system.

中文翻译：

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ARGET ATRP合成高分子量三臂星形PMMA

通过电子转移（ARGET）原子再生的活化剂成功合成了分子量分布窄（M _n = 570,000 g / mol，PDI = 1.36）的高分子量（MW），三臂星形聚甲基丙烯酸甲酯（PMMA）转移自由基聚合（ATRP）。在三乙基引发剂/ CuBr ₂ / N，N，N'，N'，N'-五甲基二亚乙基三胺（PMDETA）引发剂/催化剂体系中，在2-乙基己酸锡（II）[Sn（EH） ）₂ 在90°C下还原剂。铜催化剂的浓度低至30ppm，并且获得了高的引发位点引发效率。通过使用相同的催化剂体系，通过ARGET ATRP与苯乙烯进行的扩链实验，证实了高分子量3臂星形PMMA的链端功能。