Peng Rui, Luo Yufeng, Cui Qianling, Zhang Hean, Li Lidong
State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China.
ACS Appl Mater Interfaces. 2022 Nov 2;14(43):49254-49263. doi: 10.1021/acsami.2c17114. Epub 2022 Oct 18.
In this work, two kinds of imine-type covalent organic framework (COF) nanoparticles are demonstrated as efficient photocatalytic initiators to trigger the free-radical polymerization of acrylamide (AM) to prepare polyacrylamide (PAM) hydrogels under visible light irradiation, without any assistance from the co-initiator. Simultaneously, the COF nanoparticles bearing vinyl side groups (COF-V) promote covalent cross-linking of the polymer chains, which significantly reinforces the mechanical properties of the nanocomposite hydrogel. The obtained PAM/COF-V hydrogel is highly stretchable with an extraordinary elongation up to 3300% strain. On the other hand, the COF nanoparticles modified with methoxy moieties (COF-OMe) endow the resulting PAM/COF-OMe hydrogel with a promising fluorescence feature. In addition, this strategy provides a visible-light-regulated photocatalytic polymerization approach with a simplified recipe to fabricate COF-based nanocomposite hydrogels or resins with diverse functions.
在这项工作中，两种亚胺型共价有机框架（COF）纳米颗粒被证明是高效的光催化引发剂，可在可见光照射下引发丙烯酰胺（AM）的自由基聚合，以制备聚丙烯酰胺（PAM）水凝胶，无需共引发剂的任何辅助。同时，带有乙烯基侧基的COF纳米颗粒（COF-V）促进聚合物链的共价交联，这显著增强了纳米复合水凝胶的机械性能。所获得的PAM/COF-V水凝胶具有高度可拉伸性，具有高达3300%应变的非凡伸长率。另一方面，用甲氧基部分修饰的COF纳米颗粒（COF-OMe）赋予所得的PAM/COF-OMe水凝胶有前景的荧光特性。此外，该策略提供了一种可见光调节的光催化聚合方法，其配方简化，可制备具有多种功能的基于COF的纳米复合水凝胶或树脂。
