Supramolecular Nanostructures Enabling Mechanical Reinforcement and Recognitive Self‐Healing in Elastomers

Supramolecular assembly of biological materials into fibrous structures often provides exceptional functionalities. In the case of synthetic polymers, however, it is challenging to construct fibrous structures in the condensed matrix, primarily due to limited ordering and chain mobility for supramolecular assembly. We present a design strategy of using hydrogen bonding units to facilitate supramolecular assembly in self‐healing PDMS‐based polymer films, exploring how subtle changes in alkyl spacers affect dynamic mechanical responses. We observed that increasing structural flexibility in hydrogen bonding units enables long‐range supramolecular assemblies, leading to the formation of fibrous structures. These structures endow the material with improved mechanical stability under tensile, compressive, and frictional stresses. Notably, the supramolecular assembly responds to molecular‐level changes, allowing selective self‐healing between corresponding polymers. This molecular‐level recognition gave self‐alignment in multilayer laminates, enabling autonomous healing and alignment of damaged and misaligned layers. Our findings provide new insights for designing mechanically robust, self‐healable, and multi‐functional polymers.