Multifunctional Flexible Sensor Based on P(AA‐NIPAM)/PVA Dual‐Network Hydrogel for Monitoring Soccer Players' Motion

ABSTRACT Hydrogel‐based flexible sensors have promising applications in wearable devices, electronic skin, and smart medical devices. However, the preparation of hydrogel sensors for multifunctional sensing is still a challenging task. In this paper, Polyvinyl alcohol/Poly (acrylic acid‐N‐isopropyl acrylamide)‐Fe 3+ (PVA/P(AA‐NIPAM)‐Fe 3+ ) dual‐network multifunctional hydrogels were obtained by monomer copolymerization and ionic cross‐linking. The hydrogel not only has good mechanical properties (tensile strength: 1.91 ± 0.05 MPa, maximum elongation: 475 ± 27%), but also achieves sensing properties to stress, pressure, temperature, and pH. The sensitivity to stress was 3.77, and the response time was 90 ms. There is also a distinguishable signal output for pressure and a good linear correlation for temperature and pH sensing. The construction of this hydrogel provides a new example for the development of multifunctional hydrogel sensors.