Polymerization-Induced Self-Assembly (PISA) Using ICAR ATRP at Low Catalyst Concentration
Polymerization-Induced Self-Assembly (PISA) Using ICAR ATRP at Low Catalyst Concentration
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DOI：
10.1021/acs.macromol.6b01966
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发表时间：
2016-11-22
期刊：
影响因子：
5.5
通讯作者：
Matyjaszewski, Krzysztof
中科院分区：
文献类型：
--
作者：
Wang, Guowei;Schmitt, Michael;Matyjaszewski, Krzysztof
聚合诱导自组装（比萨）是通过在低ppm的铜催化剂浓度下进行连续活化剂再生原子转移自由基聚合（ICAR ATRP）的引发剂来实现的。以（CuCl 2）-Cl-II/三（吡啶-2-基甲基）胺（TPMA）为引发剂，采用ICAR ATRP法合成了聚（环氧乙烷低聚甲基醚甲基丙烯酸酯）（POEOMA（50））大分子引发剂和稳定剂。随后，甲基丙烯酸苄酯（BnMA）在乙醇中的分散聚合实现与（CuBr 2）-Br-II/TPMA配合物在室温下或在65 ℃下，分别使用V-70或AIBN作为自由基引发剂。采用凝胶渗透色谱（GPC）、透射电子显微镜（TEM）和动态光散射（DLS）评价了催化剂浓度、自由基引发剂、PBnMA目标聚合度（DP）、固含量和温度对嵌段共聚物POEOMA-PBnMA分子特征和自组装行为的影响。嵌段共聚物组装成球体，蠕虫状聚集体，和囊泡的直径范围从100至600 nm，这取决于温度，固体含量，和DP的PBnMA。温度对聚合行为和形态演变的影响归因于成核PBnMA嵌段在其玻璃化转变温度（Tg = 54 ° C）之上和之下的温度依赖性塑化。
Polymerization-induced self-assembly (PISA) was achieved by conducting an initiators for continuous activator regeneration atom transfer radical polymerization (ICAR ATRP) at low ppm of copper catalyst concentration. A poly(oligo(ethylene oxide) methyl ether methacrylate)(50) (POEOMA(50)) macroinitiator and stabilizer was synthesized by an aqueous ICAR ATRP using (CuCl2)-Cl-II/tris(pyridin-2-ylmethyl)amine (TPMA) complex. Subsequently, the dispersion polymerization of benzyl methacrylate (BnMA) in ethanol was realized with a (CuBr2)-Br-II/TPMA complex either at room temperature or at 65 degrees C using V-70 or AIBN as radical initiators, respectively. The effect of catalyst concentration, radical initiators, targeted degree of polymerization (DP) of PBnMA, solids content, and temperature on the molecular characteristics and self-assembly behavior of block copolymers POEOMA-PBnMA was evaluated by gel permeation chromatography (GPC), transmission electron microscopy (TEM), and dynamic light scattering (DLS). Block copolymers assembled into spheres, wormlike aggregates, and vesicles with diameters ranging from 100 to 600 nm, depending on the temperature, solids content, and the DP of PBnMA. The effect of the temperature on the polymerization behavior and morphological evolution was attributed to the temperature-dependent plasticization of the core-forming PBnMA block above and below its glass transition temperature (T-g = 54 degrees C).