Mommer Stefan, Wezenberg Sander J
Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands.
ACS Appl Mater Interfaces. 2022 Sep 28;14(38):43711-43718. doi: 10.1021/acsami.2c11136. Epub 2022 Sep 13.
Supramolecular anion binding to squaramide crosslinkers in poly(,-dimethylacrylamide) gel networks enhances swelling and allows reversible chemically driven actuation. The volume swelling ratio of the gels is shown to depend on both the type of anion and its concentration. H NMR and UV-vis titrations with the squaramide crosslinkers reveal a relationship between anion binding affinity and the concentration-dependent swelling behavior. Gel swelling is shown to be reversible, and by embedding a solid support into rod-shaped gels, soft actuators are fabricated that undergo forward and backward bending motion in response to changing anion concentration. The swelling and bending process, which is accompanied by intense green coloration of the gel, is achieved by using only low amounts of crosslinker. This macroscopic actuation achieved by anion binding to specific molecular entities in the polymer network will open new opportunities in the field of chemically responsive materials.
超分子阴离子与聚（N，N-二甲基丙烯酰胺）凝胶网络中的方酰胺交联剂结合，可增强溶胀并实现可逆的化学驱动致动。结果表明，凝胶的体积溶胀率取决于阴离子的类型及其浓度。用方酰胺交联剂进行的1H NMR和紫外可见滴定揭示了阴离子结合亲和力与浓度依赖性溶胀行为之间的关系。凝胶溶胀是可逆的，通过将固体支撑物嵌入棒状凝胶中，制造出了软致动器，其可响应阴离子浓度的变化进行向前和向后的弯曲运动。仅使用少量交联剂即可实现溶胀和弯曲过程，该过程伴随着凝胶强烈的绿色。通过阴离子与聚合物网络中特定分子实体的结合实现的这种宏观致动将为化学响应材料领域带来新的机遇。
