Supramolecular hydrogel membranes reinforced with aramid nanofibers via the dynamic cross-linking and hydrogen bonding network

Traditional ion-conducting hydrogels rely on water as the ion-transport medium, yet their practical application is hindered by susceptibility to freezing and evaporation. Herein, Inspired by the lipid structure of cell membranes, an aramid fiber (ANF)-reinforced poly(vinyl alcohol) (PVA)-based organic ion-conducting hydrogel membrane (PVA-ANF hydrogel) was fabricated by a collaborative strategy of dynamic cross-linking and hydrogen bonding network with PVA as the substrate, ANF as the reinforcement, and dimethyl sulfoxide (DMSO)/H 2 O as the binary solvent system, respectively. The incorporation of ANFs markedly enhanced mechanical strength and conferred over 99 % UV filtration capability, whereas the DMSO/H₂O system endowed the hydrogel with exceptional freeze resistance, moisture retention, and transparency. The conductivity value of the organic ion-conductive hydrogel was 1.019 S/m, which was able to precisely detect human body motions and small movements such as pulse (the strain sensitivity could reach 0.2 %) when used as a strain sensor. This work enriches the high value-added and multifunctional applications of aramid fibers and provides a novel perspective for the design of advanced strain sensors.