Design of Graft Architectures via Simultaneous Kinetic Control of Cationic Vinyl-Addition Polymerization of Vinyl Ethers, Coordination Ring-Opening Polymerization of Cyclic Esters, and Merging at the Propagating Chain End
Design of Graft Architectures via Simultaneous Kinetic Control of Cationic Vinyl-Addition Polymerization of Vinyl Ethers, Coordination Ring-Opening Polymerization of Cyclic Esters, and Merging at the Propagating Chain End
复制标题
通过同步动力学控制乙烯基醚的阳离子乙烯基加成聚合、环酯的配位开环聚合以及在增长链末端合并来设计接枝结构
DOI：
10.1021/acs.macromol.0c00531
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发表时间：
2020
期刊：
影响因子：
5.5
通讯作者：
Aoshima Sadahito
中科院分区：
文献类型：
--
作者：
Higuchi Motoki;Kanazawa Arihiro;Aoshima Sadahito
通过同步控制乙烯基醚（VE）的阳离子乙烯基加成聚合和环酯（CE）的配位开环聚合，一次性合成了多功能接枝结构。接枝共聚物是通过独立的增长反应和通过烷氧基交换将聚（CE）链瞬时掺入聚（VE）增长端的侧链而生成的。在该机制中，共聚物的接枝密度和接枝长度可以通过调节每个增长反应和交换反应的速率来设计。通过系统研究，揭示了聚合条件（例如单体和催化剂的种类和浓度）对每个反应速率的影响，并建立了各种接枝结构的设计原则。值得注意的是，获得了具有非常高的接枝密度的共聚物[最大。当具有亚乙二氧基侧链的VE与钛催化剂一起使用时，88%的聚(VE)侧链被聚(CE)链取代]。亚乙二氧基单元和钛催化剂的特定相互作用是高接枝密度的关键。
Versatile graft architectures were synthesized in one shot via simultaneous controlled cationic vinyl-addition polymerization of vinyl ethers (VEs) and coordination ring-opening polymerization of cyclic esters (CEs). Graft copolymers were generated via independent propagation reactions and transient incorporation of a poly(CE) chain into the side chain of the poly(VE) propagating end via the exchange of alkoxy groups. In this mechanism, the grafting density and grafting length of a copolymer were designable by tuning the rates of each propagation reaction and the exchange reaction. As a result of a systematic investigation, the effects of polymerization conditions, such as the kinds and concentrations of monomers and catalysts, on the rate of each reaction were revealed and a design principle of various graft architectures was established. Notably, a copolymer with a remarkably high grafting density was obtained [max. 88% of poly(VE) side chains were substituted with poly(CE) chains] when a VE with an ethylenedioxy side chain was used with a titanium catalyst. The specific interaction of an ethylenedioxy unit and a titanium catalyst was key to the high grafting density.