College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, P. R. China.
Heilongjiang Academy of Sciences, Institute of Advanced Technology, Harbin 150029, P. R. China.
ACS Appl Mater Interfaces. 2023 Mar 1;15(8):11062-11075. doi: 10.1021/acsami.2c21819. Epub 2023 Feb 14.
Conductive hydrogel-based ionic skins have attracted immense attention due to their great application prospects in wearable electronic devices. However, simultaneously achieving a combination of a single hydrogel system and excellent comprehensive performance (i.e., mechanical durability, electrical sensitivity, broad-spectrum antibacterial activity, and biocompatibility) remains a challenge. Thus, a novel poly(ionic liquid) hydrogel consisting of poly(acrylamide--lauryl methacrylate--methyl-uracil-imidazolium chloride--2-acryloylamino-2-methyl-1-propane sulfonic acid) (AAm-LMA-MUI-AMPS) was prepared by a micellar copolymerization method. Herein, MUI serves as a supramolecular crosslinker and conductive and bacteriostatic components. Owing to the multiple supramolecular crosslinks and hydrophobic association in the network, the hydrogel exhibits excellent mechanical properties (624 kPa of breaking stress and 1243 kPa of compression stress), skin-like modulus (46.2 kPa), stretchability (1803%), and mechanical durability (200 cycles under 500% strain can be completely recovered). Moreover, with the coordinated combination of each monomer, the hydrogel exhibits the unique advantage of high conductivity (up to 59.34 mS/cm). Hence, the hydrogel was further assembled as an ionic skin sensor, which exhibited a gauge factor (GF) of 10.74 and 7.27 with and without LiCl over a broad strain range (1-1000%), respectively. Furthermore, the hydrogel sensor could monitor human movement in different strain ranges, including body movement and vocal cord vibration. In addition, the antibacterial activity and biocompatibility of the hydrogel sensor were investigated. These findings present a new strategy for the design of new-generation wearable devices with multiple functions.
基于导电水凝胶的离子皮肤因其在可穿戴电子设备中的广泛应用前景而受到极大关注。然而，同时实现单一水凝胶系统与优异综合性能（即机械耐久性、电敏感性、广谱抗菌活性和生物相容性）的结合仍然是一个挑战。因此，通过胶束共聚方法制备了一种由聚（丙烯酰胺-月桂基甲基丙烯酸酯-甲基尿嘧啶-氯化咪唑鎓-2-丙烯酰氨基-2-甲基-1-丙磺酸）（AAm-LMA-MUI-AMPS）组成的新型聚离子液体水凝胶。在这里，MUI 作为超分子交联剂和导电抗菌成分。由于网络中的多重超分子交联和疏水缔合，水凝胶表现出优异的机械性能（断裂应力为 624kPa，压缩应力为 1243kPa）、类皮肤模量（46.2kPa）、拉伸性（1803%）和机械耐久性（在 500%应变下循环 200 次可完全恢复）。此外，通过各单体的协同组合，水凝胶表现出独特的高导电性优势（高达 59.34mS/cm）。因此，水凝胶进一步组装成离子皮肤传感器，在较宽的应变范围内（1-1000%）分别具有 10.74 和 7.27 的应变系数（GF）。此外，水凝胶传感器可监测人体在不同应变范围内的运动，包括身体运动和声带振动。此外，还研究了水凝胶传感器的抗菌活性和生物相容性。这些发现为设计具有多种功能的新一代可穿戴设备提供了一种新策略。
