关键词: 水凝胶, 抗冻, 植酸, 柔性应变传感器, 运动监测

Abstract: Conductive hydrogel have emerged as a promising candidate for the development of flexible sensors due to their highly compatible elastic modulus with human skin, distinct ionic conductivity, and mechanical flexibility. However, the high water content within hydrogels inevitably freeze at subzero temperature, causing a degradation or loss of functionality, which severely prevent their practical application. Herein, inspired by the antifreeze properties of natural organisms, an anti-freezing conductive hydrogel was fabricated by compositing and cross-linking multifunctional monomers(ACMO and AMPS)in phytic acid(PA)solution in the presence of collagen. The well-balanced combination of P(ACMO-co-AMPS)and collagen, along with dynamically revisable noncovalent interactions inside the hydrogel network, lead to significant enhancements in interfacial toughness, fatigue resistance, and self-adhesion. Profiting from the high conductivity and rapid response to strain, the hydrogel was assembled as strain sensor to precisely detect human activities with high strain sensitivity and wide strain range. Moreover, the strong hydrogen bonds between PA and water greatly reduced the freezing point of water, endowing hydrogel sensor with excellent frost resistance and allowing real-time detection human motion under extreme conditions. This research provides a general and scalable strategy for the development of anti-freezing conductive hydrogel flexible strain sensor to satisfy diverse wearable requirements.

Key words: hydrogel, anti-freezing, phytic acid, flexible strain sensor, motion detection