Cryopolymerized Polyampholyte Gel with Antidehydration, Self-Healing, and Shape-Memory Properties for Sustainable and Tunable Sensing Electronics.

Hydrogel-based wearable flexible electronics are attracting tremendous interest for use in human healthcare. However, many of the existing hydrogel electronics are often susceptible to dehydration, leading to weakened stretchability and inaccurate signal extraction. Besides, hydrogels are desired to be much smarter for self-repairing physical damage and enabling performance manipulation. Herein, we develop a kind of cryopolymerized polyampholyte gels with the multifunctionality of antidehydration, self-healing, and shape-memory for wearable sensing electronics. The antidehydration property is enabled by the incorporation of glycerol, endowing the sensing electronics with excellent stretchability and strain-sensing performance in long-term monitoring. The ionic bonds in the polyampholyte gel possess a dynamic feature regulated by alternant NaCl(aq) and H 2 O treatments, laying the foundation for self-healing and shape-memory. As a result, the sensing electronics can automatically repair physical damages without any sacrifice in sensing performance, after healing both conductivity and strain-sensing performance could return to the initial levels. The shape-memory function enables the temporal adjustment of the initial state of the sensing electronics; both the conductivity and sensing performance, for instance, signal intensity, can be manually manipulated. In all, the cryopolymerized polyampholyte gels with antidehydration, self-healing, and shape-memory properties can be an inspiration to develop sustainable and tunable gel-based electronics for human motion monitoring.