Gallic acid-tailored conducting polymer hydrogel with high performance for flexible sensor

Conducting hydrogels have gained great interest in the applications of flexible sensors, soft electronics, and health monitoring. However, the poor processability, limited reusability, and easy aggregation of conducting components significantly constrain the widespread implementation of traditional conducting hydrogels. Herein, the homogeneous conducting hydrogels based on polyvinyl alcohol (PVA) and polyaniline (PANI) are tailored with cheap and natural gallic acid (GA) for flexible sensors. The optimized hydrogel exhibits good mechanical properties, with a tensile strength of 1.61 MPa at a maximum elongation of 344 %, Young's modulus of 0.24 MPa, and toughness of 2.36 MJ m −3 , as well as long-term stability and reusability. The flexible sensor assembled with the as-prepared hydrogels demonstrated the desirable properties with a competitive gauge factor, sensing stability, and fast responsiveness. Therefore, the satisfactory performances enable it to monitor and distinguish different multi-scale human motions. This work fosters a PVA/PANI hydrogel platform tailored with GA, paving the way for the development of high-performance conducting hydrogels and applications in flexible electronics.