Wong Joey Hui Min, Ting Tan Rebekah Pei, Chang Jun Jie, Ow Valerie, Yew Pek Yin Michelle, Chee Pei Lin, Kai Dan, Loh Xian Jun, Xue Kun
Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore.
Department of Materials Science and Engineering, National University of Singapore (NUS), 9 Engineering Drive 1, Singapore, Singapore, 117576, Singapore.
Chem Asian J. 2022 Oct 17;17(20):e202200628. doi: 10.1002/asia.202200628. Epub 2022 Sep 22.
Supramolecular hydrogels have attracted considerable interest due to their unique stimuli-responsive and self-healing properties. However, these hydrogel systems are usually achieved by covalent grafting of supramolecular units onto the polymer backbone, which in turn limits their reprocessability. Herein, we prepared a supramolecular hydrogel system by forming dynamic covalent crosslinks between 4-carboxyphenylboronic acid (CPBA) and polyvinyl alcohol (PVA). The system was then further crosslinked with either calcium ions or branched polyethylenimine (PEI) to generate hydrogels with distinctly different properties. Incorporation of calcium ions resulted in the formation of hydrogels with higher storage modulus of 7290 Pa but without self-healing properties. On the other hand, PEI-crosslinked hydrogel (PVA-CPBA-PEI) exhibited >2000% critical strain value, demonstrated high stability over 52 days and showed sustained antibacterial effect. A combination of supramolecular interactions and dynamic covalent crosslinks can be an alternate strategy to fabricate next-generation hydrogel materials.
超分子水凝胶因其独特的刺激响应和自愈特性而备受关注。然而，这些水凝胶体系通常是通过将超分子单元共价接枝到聚合物主链上实现的，这反过来又限制了它们的可再加工性。在此，我们通过在4-羧基苯硼酸（CPBA）和聚乙烯醇（PVA）之间形成动态共价交联制备了一种超分子水凝胶体系。然后，该体系与钙离子或支化聚乙烯亚胺（PEI）进一步交联，以生成具有明显不同性质的水凝胶。引入钙离子导致形成具有7290 Pa较高储能模量但无自愈性能的水凝胶。另一方面，PEI交联水凝胶（PVA-CPBA-PEI）表现出>2000%的临界应变值，在52天内表现出高稳定性，并显示出持续的抗菌效果。超分子相互作用和动态共价交联的结合可能是制备下一代水凝胶材料的另一种策略。
