Tough and Self‐Recoverable Thin Hydrogel Membranes for Biological Applications

Tough and self‐recoverable hydrogel membranes with micrometer‐scale thickness are promising for biomedical applications, which, however, rarely be realized due to the intrinsic brittleness of hydrogels. In this work, for the first time, by combing noncovalent DN strategy and spin‐coating method, we successfully fabricated thin (thickness: 5–100 µm), yet tough (work of extension at fracture: 105–107 J m−3) and 100% self‐recoverable hydrogel membranes with high water content (62–97 wt%) in large size (≈100 cm2). Amphiphilic triblock copolymers, which form physical gels by self‐assembly, were used for the first network. Linear polymers that physically associate with the hydrophilic midblocks of the first network, were chosen for the second network. The inter‐network associations serve as reversible sacrificial bonds that impart toughness and self‐recovery properties on the hydrogel membranes. The excellent mechanical properties of these obtained tough and thin gel membranes are comparable, or even superior to many biological membranes. The in vitro and in vivo tests show that these hydrogel membranes are biocompatible, and postoperative nonadhesive to neighboring organs. The excellent mechanical and biocompatible properties make these thin hydrogel membranes potentially suitable for use as biological or postoperative antiadhesive membranes. Thin (5–100 µm), tough, and fully self‐recoverable hydrogel membranes (≈75 wt% water content) are successfully fabricated based on the double‐network concept. The membranes exhibit excellent mechanical properties superior to those of various biological membranes, biocompatibility, and postoperative antiadhesive property, foreshadowing their potential use as substitutes for biological membranes or postoperative antiadhesive membranes.