Chen Liangyu, Wang Zhihao, Fang En, Fan Zhiqiang, Song Shaofei
MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University Hangzhou 310027 China
Chem Sci. 2024 Dec 9;16(3):1250-1264. doi: 10.1039/d4sc06181k. eCollection 2025 Jan 15.
Cationic polymerization of vinyl ethers to access poly(vinyl ether) polymeric materials has been challenging due to stringent polymerization conditions and inevitable chain transfer. Herein we introduce a protocol using trifluoromethyl sulfonates to catalyze the polymerization of a series of vinyl ethers. These trifluoromethyl sulfonates are fully commercially available and can be stored under ambient conditions. Solvents and ligands have profound influences on the polymerization process, and poly(vinyl ether)s with different molecular weights, molecular weight distributions, and tacticities were obtained. A few combinations of trifluoromethyl sulfonate/solvents/O^O type ligands were explored. They showed high activities and afforded poly(vinyl ether)s with well-controlled tacticity, of which the isotacticity can be up to 81% . Poly(vinyl ether)s with high tacticities exhibit crystallization behaviors with melting points. We also probed the cationic reversible addition-fragmentation chain transfer (RAFT) polymerization of ethyl vinyl ether employing a RAFT chain transfer agent. Low molecular weight distributions (s) around 1.1 can be realized. Since trifluoromethyl sulfonates can be fed at a remarkably low catalyst loading and other chemicals are cheap and easily available, the poly(vinyl ether) polymeric materials are promisingly prepared on a large scale.
由于严格的聚合条件和不可避免的链转移，乙烯基醚的阳离子聚合以制备聚（乙烯基醚）聚合物材料一直具有挑战性。在此，我们介绍一种使用三氟甲磺酸盐催化一系列乙烯基醚聚合的方法。这些三氟甲磺酸盐完全可从商业途径获得，并且可以在环境条件下储存。溶剂和配体对聚合过程有深远影响，我们获得了具有不同分子量、分子量分布和立构规整度的聚（乙烯基醚）。我们探索了几种三氟甲磺酸盐/溶剂/O^O型配体的组合。它们表现出高活性，并提供了立构规整度得到良好控制的聚（乙烯基醚），其中全同立构规整度可达81%。高立构规整度的聚（乙烯基醚）表现出具有熔点的结晶行为。我们还使用可逆加成-断裂链转移（RAFT）链转移剂探索了乙烯基乙醚的阳离子RAFT聚合。可以实现约1.1的低分子量分布（s）。由于三氟甲磺酸盐可以以极低的催化剂负载量加入，并且其他化学品价格便宜且易于获得，因此有望大规模制备聚（乙烯基醚）聚合物材料。
