In order to clarify the research context of Polyvinyl alcohol (PVA) -based conductive hydrogel in the field of sign monitoring, and provide theoretical reference for its high-performance design and development and engineering application in the field of wearable health monitoring, this paper systematically reviewed the research progress of crosslinking preparation technology, core performance optimization strategy and physical sign monitoring application of the material. The mechanism, characteristics and application scenarios of physical and chemical cross-linking preparation systems were analyzed, and the key value of physical-chemical cross-linking collaborative application to improve the stability of material network structure was clarified. At the same time, the multi-dimensional optimization strategies for mechanics, electrical conductivity, self-healing and anti-freezing performance are sorted out, and the mechanism of action of double network construction, dynamic bond regulation, ion and solvent system optimization is clarified.
The results show that the core performance of PVA-based conductive hydrogel can be improved by the above optimization methods, and the bottleneck of single performance optimization can be broken through. Relying on the physical characteristics of ion conduction to realize reversible conversion of force-electrical signals, the material can accurately capture large movements such as joint flexion and extension, muscle contraction, and subtle physiological signals such as pulse, swallowing, and breathing. It can also be extended to multiple physical sign monitoring scenarios such as voiceprint recognition to meet a variety of practical application requirements. In the modeling study, we have systematically summarized the core physical models (e.g., the variable mass mesoscale model, the percolation-tunneling coupling model) and multiphysics modeling frameworks for ionic and nanocomposite hydrogels, clarifying the quantitative formulations and underlying physical mechanisms of each model.
Finally, this paper points out that the material currently has problems such as insufficient adaptability to extreme environments, low integration of materials and devices, and slow industrialization process. It is proposed that future research needs to transform from synthetic-oriented to mechanism-driven design, focusing on three directions: cross-link structure mechanism analysis, multi-performance collaborative optimization, and integration of materials and devices. It lays a foundation for the application of this material in the field of intelligent wearable devices.