Preparation and Properties of Environmentally Adaptable Polyacrylamide/Polyvinyl Alcohol Semi-Interpenetrating Highly Conductive Ion-Conducting Hydrogel

Abstract

Ionically conductive hydrogels have attracted increasing interest as skin-like sensors, however, it remains a challenge to fabricate ionically conductive hydrogels with excellent mechanical properties, high electrical conductivity, and high environmental adaptability for high-performance sensors. In this paper, LiCl was introduced into polyacrylamide/linear polyvinyl alcohol (PAM/PVA) composite hydrogels to prepare hydrogels with high ion conductivity. The introduction of LiCl endows the PAM/PVA/LiCl hydrogel with excellent stretchability, high electrical conductivity, good freezing resistance and water retention, and a wide working temperature range. Impressively, this ion-conducting hydrogel can be used for skin-like sensors with high strain sensitivity and excellent durability over 10 consecutive stretches. Therefore, wearable sensors assembled from hydrogels can be used to detect complex human activities with high stability even at –20°C. This work facilitates the development of ionically conductive hydrogels with wide operating temperatures on advanced sensing platforms.