Highly sensitive gellan gum/sodium lignosulfonate-modified hydrogel with temperature-adaptive properties for wearable sensor applications

This work reports on a highly sensitive and temperature-adaptive gellan gum/sodium lignosulfonate-modified hydrogel (PGL hydrogel) aimed at developing materials suitable for wearable sensors. By introducing gellan gum into the polyacrylamide (PAM) matrix, an interpenetrating network structure was formed, significantly enhancing the mechanical properties of the hydrogel. Subsequent post-treatment with a sodium lignosulfonate solution further improved the conductivity of the hydrogel to 0.48 S/m. As the core functional material for wearable sensors, this hydrogel exhibits a wide strain detection capability of approximately 400%, with a gauge factor ( GF ) of 3.79 in the 0–200% strain range and 5.16 in the 200–400% range. Notably, the material maintains synergistic stability in mechanical properties, conductivity, sensitivity, and response time across a wide temperature range of –20–60 ℃. It provides robust support for its use as a stable and sensitive strain sensor. Graphical