A Wearable Strain Sensor Based on Electroconductive Hydrogel Composites for Human Motion Detection

Hydrogels are becoming the default platform for flexible electronic applications-specifically, strain sensors. But the simultaneous realization of compliance, robustness, and strain sensitivity required, using environmentally friendly materials, remains challenging. Here a series of poly(vinyl alcohol) (PVA)-based biocomposite hydrogels, comprising variable quantities of nanocellulose and sodium alginate formed by freeze/thaw cycling, is reported. The results indicate that a hybrid hydrogel is prepared via the incorporation of conductive polypyrrole/bacterial nanocellulose composite material into the optimized PVA-based hydrogel matrix (yield strength = 6.0 MPa, elastic modulus = 2.4 MPa, stretchability >384%). The resulting hybrid material exhibits remarkable toughness, nonlinear conformability, and piezoresistivity and demonstrates good strain sensitivity over a considerable range of deformation (

Automated summary

This study reports a poly(vinyl alcohol) (PVA)-based biocomposite hydrogel with good flexibility, toughness, and strain sensitivity. By incorporating conductive polypyrrole/bacterial nanocellulose composite material into the PVA-based hydrogel matrix, a hybrid hydrogel with excellent properties is prepared.