High-strength polyvinyl alcohol-based hydrogel by vermiculite and lignocellulosic nanofibrils for electronic sensing

Abstract The use of natural polysaccharides in stretchable hydrogels has attracted more and more attention. However, pure polyvinyl alcohol (PVA) hydrogel has poor mechanical properties and low sensitivity in strain sensors. Composite hydrogels with high tensile properties (the storage modulus of 6,397.8 Pa and the loss modulus of 3,283.9 Pa) and high electrical conductivity (1.57 S·m−1) were prepared using a simple method. The Fe-vermiculite and lignocellulosic nanofibril-based hydrogels were applied as reliable and stable strain sensors that are responsive to environmental stimuli. The prepared hydrogels exhibited excellent ionic conductivity, which satisfied the needs of wrist flexion activity monitoring. The results showed that the PVA/LF0.4 hydrogel has a natural formulation, high mechanical strength, and electrical conductivity, which has great potential for application in artificial electronics. Graphical abstract Schematic illustration of the fabrication of the PVA/LF0.4 hydrogel, which is then used as conductive hydrogel in electron skin sensors due to excellently tensile (596.7%) and highly conductive (1.57 S‧m−1) properties.