Cyclodextrin Nano‐Assemblies Enabled Robust, Highly Stretchable, and Healable Elastomers with Dynamic Physical Network

Abstract Artificial materials with biomimic self‐healing ability are fascinating, however, the balance between mechanical properties and self‐healing performance is always a challenge. Here, a robust, highly stretchable self‐healing elastomer with dynamic reversible multi‐networks based on polyurethane matrix and cyclodextrin‐assembled nanosheets is proposed. The introduction of cyclodextrin nano‐assemblies with abundant surface hydroxyl groups not only forms multiple interfacial hydrogen bonding but also enables a strain‐induced reversible crystalline physical network owing to the special nanoconfined effect. The formation and dissociation of a dynamic crystalline physical network under stretching–releasing cycles skillfully balance the contradiction between mechanical robustness and self‐healing ability. The resulting nanocomposites exhibit ultra‐robust tensile strength (40.5 MPa), super toughness (274.7 MJ m −3 ), high stretchability (1696%), and desired healing efficiency (95.5%), which can lift a weight ≈ 100 000 times their own weight. This study provides a new approach to the development of mechanically robust self‐healing materials for engineering applications such as artificial muscles and healable robots.