Freezing-tolerant and robust gelatin-based supramolecular conductive hydrogels with double-network structure for wearable sensors
Jia Yang, Xiangbin Sun, Qiong Kang, Lin Zhu, Gang Qin, Qiang Chen
Abstract
It is significant to design stretchable conductive hydrogels with high integrated mechanical and excellent anti-freezing performances for broadening their application fields. Herein, a freezing-tolerant and robust poly(N-hydroxymethyl acrylamide)/gelatin/glycerol supramolecular conductive hydrogel with double networks is synthesized via an one-pot method, where poly(N-hydroxymethyl acrylamide) can self-cross-link, and also interact with gelatin. Glycerol endows the conductive hydrogel with anti-freezing property in mechanics and electricity, and can also interact with poly(N-hydroxymethyl acrylamide) and gelatin to further enhance mechanical properties. Under optimal conditions, the conductive hydrogel exhibits high strength, super extensibility, rapid self-recovery, excellent fatigue resistance and high ionic conductivity. It possesses temperature insensitivity of mechanical properties and weak dependence of electrical behaviors on temperature. Furthermore, it exhibits excellent anti-freezing resistance response to strain, and can as sensor detect human activities. Thus, this work provides a simple and promising strategy for designing stretchable conductive gels with integrated high performances aiming for wearable intelligent electronics.