Ultrastretchable, Crack-Propagation-Resistant, and Impact-Resistant Ionic Conductive Ionohydrogels

Abstract

Ionogels equipped with high ionic conductivity, excellent thermal/chemical/electrochemical stability, and flexibility have been considered ideal candidates for hydrogels. However, the long-term reliability against fatigue and impact resistance of ionogels remains a crucial challenge that hinders their practical application and has yet to be addressed by effective strategies. Herein, a multiple noncovalent interaction strategy inspired by the water retention properties of human skin collagen has been proposed to achieve the synergistic effect of physical entanglement and microphase separation. Moreover, the introduction of collagen, a biomacromolecule, creates cohesion of the microphase and multiple hydrogen bonds. Thus, the fabricated ionohydrogels perfectly exhibit unprecedented ultrastretchability (>6500%) and impact resistance properties. They can stably maintain 300 times their own volume expansion and resist puncture by sharp objects. Furthermore, the proposed ionohydrogels have overcome the bottleneck problems of crack propagation resistance and impact resistance that have plagued their development. We can predict that this multiple noncovalent interaction strategy will provide theoretical and experimental accumulation for the practical and extensive development of ionohydrogels.