Wang Qingqing, Sun Zhiyi, Zhang Zhaoming, Zhou Chengfeng, Zhang Tonghua, Wang Tao
College of Sericulture, Textile and Biomass Sciences, State Key Laboratory of Resource Insects, Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile, Southwest University, Chongqing 400715, China.
State Key Laboratory of Bio-Fibers and Eco-Textiles (Qingdao University), China.
Int J Biol Macromol. 2025 Jun;315(Pt 2):144498. doi: 10.1016/j.ijbiomac.2025.144498. Epub 2025 May 21.
Conductive hydrogels made of eco-friendly materials have been concerned in the field of flexible electronic devices (FEDs). Great efforts have been made to improve mechanical properties of conductive hydrogels, which are still unsatisfactory for natural polymer hydrogels. Herein, a strategy to improve mechanical properties of chitosan-based hydrogels by constructing dual ionic networks via cations and anions is reported. Through the double crosslinking of high-valent cations (Al) and anions (SO) with the polymers, as well as the salting-out effect of salts, the resulting hydrogels have evolved tensile strength and toughness, which are up to 8 MPa and 28.4 MJ/m, respectively. The reversible ionic networks play a vital role in tensile recovery, further leading to stability in the relative resistance change of the hydrogels under various deformation. The dual ionic crosslinked hydrogels possess moderate gauge factor (1.2-2.9) at tensile strain from 100 % to 400 %, which are sensitive to monitor human movements as flexible strain sensors. In addition, the hydrogels show perfect antibacterial activity against E. coli and S. aureus. Overall, this work provides an effective way to fabricate strong and tough conductive hydrogels based on chitosan for promising application of FEDs.
由环保材料制成的导电水凝胶在柔性电子器件（FEDs）领域受到关注。人们已付出巨大努力来改善导电水凝胶的机械性能，但对于天然聚合物水凝胶而言，其机械性能仍不尽人意。在此，报道了一种通过阳离子和阴离子构建双离子网络来改善壳聚糖基水凝胶机械性能的策略。通过高价阳离子（Al）和阴离子（SO）与聚合物的双重交联以及盐的盐析效应，所得水凝胶具有高达8 MPa的拉伸强度和28.4 MJ/m的韧性。可逆离子网络在拉伸恢复中起着至关重要的作用，进一步使水凝胶在各种变形下的相对电阻变化保持稳定。双离子交联水凝胶在100%至400%的拉伸应变下具有适中的应变系数（1.2 - 2.9），作为柔性应变传感器对监测人体运动很敏感。此外，该水凝胶对大肠杆菌和金黄色葡萄球菌显示出优异的抗菌活性。总体而言，这项工作为基于壳聚糖制备坚固且坚韧的导电水凝胶提供了一种有效方法，有望应用于柔性电子器件。
