CO2-Breathing Polymer Assemblies via One-Pot Sequential RAFT Dispersion Polymerization
CO2-Breathing Polymer Assemblies via One-Pot Sequential RAFT Dispersion Polymerization
复制标题
通过一锅连续 RAFT 分散聚合制备呼吸二氧化碳聚合物组件
DOI：
10.1002/marc.201800291
复制
发表时间：
2018
影响因子：
4.6
通讯作者：
Yuan Jinying
中科院分区：
文献类型：
--
作者：
Zeng Min;Huo Meng;Feng Yujun;Yuan Jinying
以聚[低聚（乙二醇）甲基丙烯酸甲酯]- b -聚（甲基丙烯酸苄酯）- b -聚[2 -（二乙胺）甲基丙烯酸乙酯]（POEGMA - b - PBnMA - b - PDEA）为基础，通过一锅顺序可逆加成-破碎链转移分散聚合制备了具有可逆“呼吸”行为的ABC三嵌段共聚物。使用POEGMA作为大分子链转移剂，在乙醇中与BnMA和DEA进行链扩展，其中PBnMA作为核心形成块，PDEA块赋予亲溶剂性和CO2响应性。随着PBnMA DP的增加，组合体形态由球状向蠕虫状、囊泡状演变，随着PDEA DP的增加，组合体形态由粘连囊泡向球状退化。在用水取代乙醇后，这些组装体的形态保持不变，但由于疏水PDEA链的崩溃，它们的尺寸减小了。有趣的是，由于PDEA块的质子化和去质子化，球体和囊泡在交替的CO2/Ar刺激下都表现出可逆的膨胀/收缩，表现出明显的呼吸特征。
ABC triblock copolymer assemblies with reversible “breathing” behaviors based on poly[oligo(ethylene glycol) methyl ether methacrylate]‐b‐poly(benzyl methacrylate)‐b‐poly[2‐(diethylamino)ethyl methacrylate] (POEGMA‐b‐PBnMA‐b‐PDEA) are fabricated via one‐pot sequential reverisble addition‐fragmentation chain transfer dispersion polymerization. Using a POEGMA as the macromolecular chain transfer agent, chain extension with BnMA and DEA is conducted in ethanol, where PBnMA acts as the core‐forming block, and the PDEA block endows the solvophilicity and CO2‐responsiveness. With the increment of the DP of PBnMA, the morphology of the assemblies evolves from spheres to worms, and to vesicles, while it degenerates from conglutinated vesicles to spheres as the DP of PDEA increases. After replacing ethanol with water, the morphologies of these assemblies remain unchanged, while their size decreases due to the collapse of the hydrophobic PDEA chains. Interestingly, due to the protonation and deprotonation of PDEA blocks, both the spheres and vesicles manifest a reversible expansion/shrinkage upon alternative CO2/Ar stimulation, exhibiting distinctive breathing feature.