Alternating Methyl Methacrylate/ n -Butyl Acrylate Copolymer Prepared by Atom Transfer Radical Polymerization
Alternating Methyl Methacrylate/ n -Butyl Acrylate Copolymer Prepared by Atom Transfer Radical Polymerization
复制标题
原子转移自由基聚合制备甲基丙烯酸甲酯/丙烯酸正丁酯交替共聚物
DOI：
10.1021/acsmacrolett.2c00517
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发表时间：
2022
影响因子：
7.015
通讯作者：
Matyjaszewski, Krzysztof
中科院分区：
文献类型：
--
作者：
Yin, Rongguan;Zhao, Yuqi;Gorczyński, Adam;Szczepaniak, Grzegorz;Sun, Mingkang;Fu, Liye;Kim, Khidong;Wu, Hanshu;Bockstaller, Michael R.;Matyjaszewski, Krzysztof
以2-乙基甲基丙烯酸甲酯（EFMA）和丙烯酸正丁酯（BA）为活化剂，通过电子转移（ARGET）原子转移自由基（co）聚合（ATRP）和聚合后改性（PPM）再生活化剂，合成了具有交替结构的聚（甲基丙烯酸甲酯/丙烯酸正丁酯）[P(MMA/BA)]共聚物。由于EFMA庞大的悬垂基团的位阻，以及BA与甲基丙烯酸酯共聚时的低反应性比，EFMA与BA共聚产生了高含量的交替二元共聚物。随后的交替EFMA/BA共聚物的PPM过程由三氟乙酸水解叔酯和（三甲基硅基）重氮甲烷甲基化组成。改性后得到的交替MMA/BA共聚物的结构与总体组成、分子量和分散度相似的梯度共聚物和统计共聚物进行了比较。13C核磁共振显示不存在MMA/MMA/MMA或BA/BA/BA序列，而在统计上，特别是在梯度共聚物中都有丰富的同源三联体。通过差示扫描量热法（DSC）测量，所有三种共聚物具有相似的玻璃化转变温度，但交替共聚物的玻璃化转变范围最窄。
Poly(methyl methacrylate/n-butyl acrylate) [P(MMA/BA)] copolymer with an alternating structure was synthesized via an activator regenerated by electron transfer (ARGET) atom transfer radical (co)polymerization (ATRP) of 2-ethylfenchyl methacrylate (EFMA) andn-butyl acrylate (BA) with subsequent postpolymerization modifications (PPM). Due to the steric hindrance of the bulky pendant group of EFMA, as well as the low reactivity ratio of BA in copolymerization with methacrylates, copolymerization of EFMA and BA generated a copolymer with a high content of alternating dyads. A subsequent PPM procedure of the alternating EFMA/BA copolymer was comprised of the hydrolysis of a tertiary ester by trifluoroacetic acid and methylation by (trimethylsilyl)diazomethane. After the modifications, the architecture of the obtained alternating MMA/BA copolymers was compared with gradient and statistical copolymers with overall similar compositions, molecular weights, and dispersities.13C NMR indicated the absence of either MMA/MMA/MMA or BA/BA/BA sequences, in contrast to an abundance of homotriads in either the statistical or especially in the gradient copolymer. All three copolymers had similar glass transition temperatures, as measured by differential scanning calorimetry (DSC), but the alternating copolymer had the narrowest range of glass transition.