Anisotropic wood cellulose-based multifunctional cellulosic hydrogel integrating boronic-ionic dynamics for wearable and structural sensing applications

Wood-derived anisotropic cellulosic scaffolds provide a sustainable platform for constructing multifunctional hydrogels for flexible sensing applications. Here, we fabricate an anisotropic, multifunctional wood cellulose-based composite hydrogel PAM-PIBPA/WCS constructed by in situ polymerizing a boronic-acid-functionalized ionic-liquid monomer (VIBPA) into a polyacrylamide (PAM) network within a delignified wood scaffold (WCS). VIBPA introduces reversible boronate-ester linkages and rich noncovalent interactions, strengthening interfacial coupling between the hydrogel and the hierarchical cellulose framework. The resulting PAM-PIBPA/WCS displays pronounced mechanical anisotropy: along the wood-fiber (longitudinal) direction it achieves high strength and modulus, whereas across fibers (transverse) it retains high compliance and stretchability. Meanwhile, ionic functionality of VIBPA imparts high conductivity (up to 5.25 mS cm⁻¹), efficient self-healing (∼96% recovery), robust adhesion (150–275 mN cm⁻¹ on diverse substrates), and strong antibacterial activity (>99% inhibition of E. coli and S. aureus ), while maintaining cytocompatibility, antifreezing ability, and moisture retention. Strain sensors based on this hydrogel show anisotropic electromechanical sensitivity ( GF 8.67 longitudinal, 7.74 transverse) with rapid, reversible responses under cyclic deformation, enabling sensitive motion monitoring (transverse) and reliable structural-deformation tracking such as trampoline dynamics (longitudinal). This work demonstrates a high-value utilization strategy for wood-derived cellulose and provides a sustainable route to multifunctional bio-based sensing materials. • Wood-derived anisotropic cellulose scaffold enables multifunctional hydrogels. • Boronic-ionic networks create dynamic ion-rich transport pathways. • The hydrogel achieves high gauge factor and fast anisotropic sensing. • Conductivity, self-healing and biocompatibility support wearable sensing.