Tough PVA/Cellulose Gels Constructed by Synergistic Freeze‐Thaw, Drying, and Solvent Exchange Strategy

ABSTRACT To address the insufficient mechanical properties of poly(vinyl alcohol) (PVA) gels, this study designed a synergistic strategy combining multiple freeze‐thaw cycles, drying densification, and solvent exchange. By introducing cellulose as a rigid reinforcing phase, a PVA/cellulose composite gel with enhanced mechanical properties was prepared. First, freeze‐thaw cycling induces microcrystalline crosslinking in PVA and concurrently promotes a hydrogen‐bonding network between cellulose and PVA chains. Subsequently, drying removes free water, driving the polymer chains into close packing and significantly increasing network density and crystallinity. Finally, solvent exchange with a glycerol aqueous solution is performed, in which glycerol molecules form hydrogen bonds with the gel network, effectively inhibiting water‐induced swelling disruption and stabilizing the dense structure formed after drying. The resulting gel exhibits excellent mechanical properties, with a tensile strength of 2.82 MPa and a fracture strain of 698%. Further annealing treatment leads to additional improvement in performance, increasing the strength to 3.98 MPa and the strain to 764%. This study provides an effective and scalable strategy for fabricating high‐performance PVA‐based composite gels through component reinforcement and the design of physically crosslinked networks.