Preparation And Application Of High Strength/self-repairable Polyacrylamide Hydrogels

Self-repairing hydrogels have water retention,proper elasticity and network structure,and can restore the original structure and mechanical properties after damage.The system contains a large amount of water and three-dimensional mesh structure of the void,after the introduction of salt solution or ionic liquid,to provide a good channel for the migration of ions,can give hydrogel with good electrical conductivity.Ionconductive hydrogels are not only characterized by good electrical conductivity,biocompatibility and tunable mechanical properties,but also by self-healing,transparency and sensitive electrochemical properties and properties that closely resemble those of living tissues,making them highly sought after in many fields such as medical and bionanotechnology.In this paper,a new P(AM-HEA-PBA)self-healing hydrogel was obtained by simple one-pot free radical polymerization of acrylamide,phenylboronic acid,and 2-hydroxyethyl acrylate as copolymer monomers with KPS as initiator and TEMED as promoter under low-temperature alkaline(p H=9)conditions.The results of FTIR,XPS,TGA and mechanical properties showed that the P(AM-HEA-PBA)self-healing hydrogels with good biocompatibility,high strength and self-healing ability were successfully prepared.This is due to the fact that the crosslinking point of the threedimensional structure of the system is composed of dynamic borate ester bonds and a large number of hydrogen bonds,which endows the P(AM-HEA-PBA)self-healing hydrogel with good mechanical properties(tensile strength of about 472 k Pa and elongation at break of about 1103%),good fatigue resistance and good biocompatibility,etc.The P(AM-HEA-PBA)self-healing hydrogel is suitable for smart medical and health care applications.P(AM-HEA-PBA)self-repairing hydrogels have great potential in the fields of intelligent medical health,motion detection,human-machine interface and cell scaffolding.Based on P(AM-HEA-PBA)self-healing hydrogels,P(AM-HEA-PBA)/Na conductive hydrogels were further prepared by in situ polymerization with the introduction of Na Cl and assembled to prepare flexible sensors.The characterization results of FTIR,XPS,TGA,UV-Vis,mechanical properties and electrochemical workstations show that AM-HEA-PBA/Na conductive hydrogel still has good mechanical properties,efficient and fast self-healing ability(repair time about4 h,tensile strength repair >90%),good transparency and high sensitivity.In this paper,an AM-HEA-PBA/Na hydrogel with self-healing properties and conductivity is prepared by a simple method,which has a good prospect for the application in flexible sensors with self-healing ability.