Ionic Conductive Hydrogels Toughened By Latex Particles For Strain Detection

Flexible wearable sensors with excellent ductility and flexibility can convert external changes such as temperature,humidity,deformation and pressure into detectable electrical signals,which have great development potential in electronic skin,soft robots and various intelligent electronic products,and have attracted extensive attention from researchers.Among various materials,conductive hydrogels exhibit excellent flexibility,stretchability,conductivity and other properties,which have become ideal candidates for preparing wearable strain sensing devices.However,most strain sensors based on hydrogels have poor self-healing and fatigue resistance,which causes the strain sensitivity of the sensor to be greatly affected during the cycle of use.Therefore,the preparation of a conductive hydrogel with high strength,anti-fatigue and self-recovery is very important for the further development of wearable sensors.In this paper,poly(methyl methacrylate)-co-poly(butyl acrylate)emulsion particles(P(AAM-co-HMA)-LPS)were prepared by emulsion polymerization and are introduced into the hydrophobic association hydrogel system as the physical crosslinking center to prepare the hydrogel materials with high strength,excellent self-recovery and fatigue resistance.The dynamic physical cross-linked network structure of emulsion particles can effectively dissipate energy through the destruction and reconstruction of molecular chain segments,thereby having excellent stretchability,self-recovery and fatigue resistance.In addition,hydrogels also have good strain and pressure response behaviors,showing the advantages of high sensitivity(GF=9.31),fast response(220 ms),durability and so on.Therefore,they can be assembled into wearable sensors that can monitor a wide range of human movements and provide accurate signal feedback,including large-scale joint bending of fingers,wrists,elbows and other small vocal behaviors.Therefore,the ionic conductive hydrogel toughened by the emulsion particles shows a good application prospect in the fields of electronic skin,medical monitoring and artificial intelligence.