Dynamic Nanoconfinement Enabled Highly Stretchable and Supratough Polymeric Materials with Desirable Healability and Biocompatibility

Abstract Lightweight polymeric materials are highly attractive platforms for many potential industrial applications in aerospace, soft robots, and biological engineering fields. For these real‐world applications, it is vital for them to exhibit a desirable combination of great toughness, large ductility, and high strength together with desired healability and biocompatibility. However, existing material design strategies usually fail to achieve such a performance portfolio owing to their different and even mutually exclusive governing mechanisms. To overcome these hurdles, herein, for the first time a dynamic hydrogen‐bonded nanoconfinement concept is proposed, and the design of highly stretchable and supratough biocompatible poly(vinyl alcohol) (PVA) with well‐dispersed dynamic nanoconfinement phases induced by hydrogen‐bond (H‐bond) crosslinking is demonstrated. Because of H‐bond crosslinking and dynamic nanoconfinement, the as‐prepared PVA nanocomposite film exhibits a world‐record toughness of 425 ± 31 MJ m −3 in combination with a tensile strength of 98 MPa and a large break strain of 550%, representing the best of its kind and even outperforming most natural and artificial materials. In addition, the final polymer exhibits a good self‐healing ability and biocompatibility. This work affords new opportunities for creating mechanically robust, healable, and biocompatible polymeric materials, which hold great promise for applications, such as soft robots and artificial ligaments.