Ren Aobo, Yong Yufei, Jia Lianghao, Xiang Tao, Zhou Shaobing
Institute of Biomedical Engineering, College of Medicine, Southwest Jiaotong University, Chengdu 610031, China.
Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
ACS Appl Mater Interfaces. 2025 Jun 25;17(25):37162-37174. doi: 10.1021/acsami.5c08457. Epub 2025 Jun 13.
Conductive hydrogels have been widely used in bioelectronics due to their excellent flexibility, electrical conductivity, and biocompatibility. However, the water in hydrogels is prone to freezing at low temperatures, decreasing flexibility and sensing performance. In this work, a dual-network eutectogel composed of poly(vinyl alcohol) and poly(acrylic acid) is prepared by using deep eutectic solvent (DES) and MXene as the antifreezing medium and conductive component, respectively. The molecular dynamics simulations analyze the interaction of DES and HO in the networks to verify the effect of DES in eutectogel. Then the ratio of DES and HO in the networks is optimized by the mechanical properties, water loss resistance, and antifreezing properties. The eutectogel has good tensile properties (a strain of 570%), reliable repeatability, and excellent antifreezing performance (it can work at -80 °C). The introduction of MXene effectively enhances the sensitivity of the eutectogel sensor to 12.25, which is 6.5 times higher than that without MXene. The eutectogel-based strain sensor allows motion monitoring and encrypted information transmission at -30 °C. Combining the sensor with a soft gripper can also enable object grasping and size recognition. The eutectogel holds promise for the application of flexible sensors in extreme environments.
导电水凝胶因其优异的柔韧性、导电性和生物相容性而在生物电子学中得到广泛应用。然而，水凝胶中的水在低温下容易结冰，从而降低柔韧性和传感性能。在这项工作中，分别使用低共熔溶剂（DES）和MXene作为抗冻介质和导电成分，制备了一种由聚乙烯醇和聚丙烯酸组成的双网络低共熔凝胶。分子动力学模拟分析了DES与网络中HO的相互作用，以验证DES在低共熔凝胶中的作用。然后通过力学性能、抗失水性能和抗冻性能优化网络中DES与HO的比例。该低共熔凝胶具有良好的拉伸性能（应变达570%）、可靠的重复性和优异的抗冻性能（可在-80°C下工作）。MXene的引入有效地将低共熔凝胶传感器的灵敏度提高到12.25，比不含MXene时高出6.5倍。基于低共熔凝胶的应变传感器能够在-30°C下进行运动监测和加密信息传输。将该传感器与软夹爪相结合还能够实现物体抓取和尺寸识别。这种低共熔凝胶在极端环境下的柔性传感器应用方面具有广阔前景。
