A self-adhesive and low-temperature-tolerant strain sensor based on organohydrogel for extreme ice and snow motion monitoring

Abstract

The design of conductive hydrogel materials with cold-adaptive and flexible properties is of great practical significance for preparing flexible wearable electronics to adapt to the application needs of different environments. However, traditional hydrogel-based sensors are often severely affected in terms of operating temperature range, detection accuracy, and long-term stability under extreme environments. In this study, inspired by the freezing resistance and adhesion chemistry of organisms in the nature, an organohydrogel with self-adhesive characteristics and extreme temperature tolerance, consisting of a binary solvent system of water and glycerol, is fabricated. A pyrogallol–borate complex and polypyrrole nanoparticles are incorporated into the polymer networks, which provide excellent adhesion and electrical conductivity to the organohydrogel, respectively. This conductive and shape-adaptable organohydrogel exhibits extraordinary self-adhesion, suitable mechanical strength, and excellent fatigue resistance for meeting personalized application requirements. Meanwhile, it can withstand a low temperature of −80 °C for 24 h without freezing and maintain an excellent electrical conductivity (0.12 S m−1) and high gauge factor (GF = 4.9). Therefore, the organohydrogel-based sensor exhibits excellent antifreeze properties and can be used in personal health and human–machine interfaces for extreme ice and snow sports. More importantly, the sensor can also simulate the standard of real-time capture of the skier’s body movements, providing a reference for judges to score. This study provides an exciting new direction for the development of wearable strain sensing devices.