High-Efficiency Preparation of Macrocyclic Diblock Copolymers via Selective Click Reaction in Micellar Media
High-Efficiency Preparation of Macrocyclic Diblock Copolymers via Selective Click Reaction in Micellar Media
复制标题
胶束介质中选择性点击反应高效制备大环二嵌段共聚物
DOI：
10.1021/ja808772z
复制
发表时间：
2009-02-11
影响因子：
15
通讯作者：
Liu, Shiyong
中科院分区：
文献类型：
--
作者：
Ge, Zhishen;Zhou, Yueming;Liu, Shiyong
我们报告了一种新策略，通过超分子自组装和“选择性”点击反应的结合，依靠末端反应基团之间空间可及性的精细控制，以相对高的浓度高效制备大环二嵌段共聚物。线性前体α-炔基-omega-叠氮基异二官能聚(2-(2-甲氧基乙氧基)乙基甲基丙烯酸酯)-b-聚(低聚(乙二醇)甲基醚甲基丙烯酸酯)、线性-PMEO(2)MA-b-POEGMA-N-3在高温下自组装成具有PMEO(2)MA核和POEGMA冠的胶束。反应性炔基和叠氮基团之间的空间分离阻止了胶束实体内的点击反应。另一方面，由于单聚体-胶束交换平衡以及单聚体浓度通常为二（临界胶束化浓度，CMC）的事实，点击反应仅发生在单聚体上。这最终导致所有线性前体的完全分子内环化。
We report a novel strategy for the high-efficiency preparation of macrocyclic diblock copolymers at relatively high concentrations via the combination of supramolecular self-assembly and "selective" click reactions, relying on the fine control of spatial accessibility between terminal reactive groups. The linear precursor, alpha-alkynyl-omega-azido heterodifunctional poly(2-(2-methoxyethoxy)ethyl methacrylate)-b-poly(oligo(ethylene glycol) methyl ether methacrylate), linear-PMEO(2)MA-b-POEGMA-N-3, self-assembles into micelles with PMEO(2)MA cores and POEGMA coronas at elevated temperatures. The spatial separation between reactive alkynyl and azide groups precludes click reactions within micelle entities. On the other hand, due to the unimer-micelle exchange equilibrium and the fact that unimer concentration is typically tow (critical micellization concentration, CMC), click reactions occur exclusively for unimers. This eventually led to complete intramolecular cyclization of all linear precursors.