Anti-freezing, moisturizing, resilient and conductive organohydrogel for sensitive pressure sensors

摘要

Conductive hydrogels have attracted significant attention in the area of wearable pressure sensors due to their mechanical flexibility, conductivity and self-healing capability. At subzero temperatures, waterbased conductive hydrogels unavoidably lose their elasticity and conductivity which limits their practical usages at low temperatures. However, traditional conductive hydrogels are short of moisturizing and anti-freezing ability due to the limitation of pure water solvent, which greatly restricts their application in extreme environments. In this study, an anti-freezing and moisturizing conductive double network organohydrogel was prepared by incorporating thioctic acid (TA) with polyvinyl alcohol-borate (PVAPB) in carbon nanotubes (CNTs) that were dispersed in water (H2O) and ethylene glycol (EG). The asprepared PVA-B-TA-CNTs organohydrogel presented outstanding anti-freezing performance (-60 C-o), long-term moisturizing property (30 days), excellent stability (400 cycles) and fascinating conductive sensitivity (S = 0.625 kPa (1)). The occurrence of dynamic covalent disulfide bonds and noncovalent hydrogen bonds endow the conductive organohydrogels with brilliant remoldability and self-healing ability, which are significant for practical applications. These remarkable advantages make PVA-B-TA-CNTs organohydrogel to have enormous potential in the application of wearable and flexible pressure sensors, human-healthy monitor, and intelligence devices. (C) 2021 Published by Elsevier Inc.