The fundamental properties of a polymeric material are ultimately governed by its structure, which mainly relies on monomer composition and connection, topology, chain length, and polydispersity. Thus far, these structural characteristics are typically set ex situ by the specific polymerization procedure, eventually limiting the future design space for the creation of more sophisticated polymers. Herein, we report on a single photoswitchable catalyst system, which enables in situ remote control over the ring-opening polymerization of l-lactide and further allows regulation of the incorporation of trimethylene carbonate and δ-valerolactone monomers in copolymerizations. By implementing a phenol moiety into a diarylethene-type structure, we exploit light-induced keto–enol tautomerism to switch the hydrogen-bonding-mediated monomer activation reversibly ON and OFF. This general and versatile principle allows for exquisite external modulation of ground-state catalysis of a living polymerization process in a closed system by ultraviolet and visible light and should thereby facilitate the generation of new polymer structures.

聚合材料的基本性能最终取决于其结构，该结构主要取决于单体组成和连接，拓扑，链长和多分散性。到目前为止，这些结构特征通常是通过特定的聚合程序在异地设定的，最终限制了未来设计空间以产生更复杂的聚合物。在本文中，我们报告了一个单一的光开关催化剂系统，该系统可对l的开环聚合进行就地远程控制。-丙交酯并进一步允许调节碳酸亚丙酯和δ-戊内酯单体在共聚反应中的掺入。通过将苯酚部分转变成二芳基乙烯型结构，我们利用光诱导的酮-烯醇互变异构现象可逆地打开和关闭氢键介导的单体活化。该通用的通用原理允许在封闭系统中通过紫外线和可见光对活性聚合过程的基态催化进行精细的外部调节，从而应有助于生成新的聚合物结构。