Self‐Healing Hydrogels as Flexible Sensor for Human Motion Monitoring

Abstract Self‐healing hydrogels were prepared by mixing the difunctionalized polyethylene glycol (DF‐PEG) and chitosan (CS) in water. Due to the formation of Schiff base bond between DF‐PEG and CS, the gelation could be realized in several seconds. Determined by the SEM showed that the hydrogel was composed of porous network structure. The dynamic formation and dissociation of Schiff base bond (−C=N−) between the aldehyde group of DF‐PEG and amino group of CS initiated the excellent self‐healing property and reversible pH responsivity of hydrogels. Additionally, the hydrogels had excellent ductility and toughness with the fracture strain and stress of 88.2 % and 12.1 kPa. The hydrogels exhibited excellent strain sensing performance, which can be fabricated as the flexible sensor for real‐time monitoring the large and delicate human motions. As a result, it is expected that the obtained self‐healing hydrogels will broaden the application of gels in wearable electronics.