Photo-crosslinking ionic conductive PVA-SbQ/FeCl₃ hydrogel sensors

A polyvinyl alcohol bearing styrylpyridinium group (PVA-SbQ)/FeCl3 hydrogel sensor with a unique double crosslinked single network was prepared by UV photo-crosslinking and ionic coordination interaction. The PVA-SbQ/FeCl3 hydrogel possessed remarkable stretchability, good tensile stress, high ionic conductivity, fine sensitivity, excellent water retention capacity, and great biocompatibility. Structural diagram and properties of PVA-SbQ/FeCl3 hydrogels sensor. ABSTRACT Conductive hydrogels are attracting intensive attention as promising materials for versatile applications such as human motion sensors, sensory skin and soft robotics. However, traditional hydrogels with single-network always have poor mechanical properties, while those with double-network are difficult to be prepared and inevitable to utilize chemical crosslinking agents which are poisonous. Herein, a polyvinyl alcohol bearing styrylpyridinium group (PVA-SbQ)/FeCl3 hydrogel sensor with unique double-crosslinked single network was prepared by UV photo-crosslinking and ionic coordination interaction. The PVA-SbQ/FeCl3 hydrogel possessed remarkable stretchability (-858%), good tensile stress (-0.3 MPa), high ionic conductivity (0.29 S/m), fine sensitivity, and excellent water retention ability due to the photo-crosslinking, physical crosslinking and hydrogen bond interaction worked in tandem and the introduction of Fe3+ ions. These properties endowed the PVA-SbQ/FeCl3 hydrogel with the potential for practical applications as flexible electronic components.