福州大学Saihu Liao团队的一项最新研究的研究开发出了采用有机光催化剂进行严格时间控制的乙烯醚无金属阳离子聚合。 这一研究成果于2021年4月26日发表在国际顶尖学术期刊《美国化学会杂志》上。

课题组介绍了一种新型的有机光催化剂双膦酸盐，该盐在乙烯基醚的光调节可逆加成-片段链转移阳离子聚合中表现出出色的性能，并允许以可预测的分子量和在可见光下低ppm的窄分散度合成聚乙烯基醚。特别是可调的氧化还原电位和优异的稳定性，使双膦盐具有严格的时间控制能力，使无金属聚合长时间的黑暗期得以停止。

据了解，通过对链扩展的时间空间控制，可见光调控的有机催化光氧化还原阳离子聚合为构建无金属、界限明确的聚合物和材料提供了一种有吸引力的方法。然而，到目前为止，能够介导乙烯醚阳离子聚合的有机光催化剂还相当有限，而且由于难以达到良好的活化-失活平衡，往往会影响光控或效率，这在很大程度上取决于催化剂的氧化还原性能。

附：英文原文

Title: Metal-Free Cationic Polymerization of Vinyl Ethers with Strict Temporal Control by Employing an Organophotocatalyst

Author: Xun Zhang, Yu Jiang, Qiang Ma, Siping Hu, Saihu Liao

Issue&Volume: April 26, 2021

Abstract: By virtue of spatiotemporal control over the chain propagating, visible-light-regulated organocatalytic photoredox cationic polymerization provides an appealing approach for the construction of metal-free, well-defined polymers and materials. However, so far, organic photocatalysts capable of mediated cationic polymerization of vinyl ethers are quite limited, and the photocontrol or efficiency is often eroded due to the difficulty in achieving a good activation–deactivation balance, which is greatly dependent on the redox property of the catalyst. Here, we introduce a new type of organic photocatalysts, bisphosphonium salts, which show high performance in the photoregulated reversible addition–fragmentation chain transfer cationic polymerization of vinyl ethers and allow the synthesis of poly(vinyl ethers) with predictable molecular weights and narrow dispersities at low ppm catalyst loadings under visible light. In particular, the tunable redox potential and excellent stability endow the bisphosphonium salts strict temporal control, thus enabling the metal-free polymerization with a halt in a long dark period.

DOI: 10.1021/jacs.1c02500

Source: https://pubs.acs.org/doi/10.1021/jacs.1c02500