Supramolecular Polymer Additives as Repairable Reinforcements for Dynamic Covalent Networks

Abstract Employing rigid (in)organic materials as reinforcement for dynamic covalent networks (DCNs) is an effective approach to develop high‐performance materials. Yet, recycling of these materials after failure often necessitates inefficient chemical reprocessing or inevitably alters their performance due to unrepairable inert components. Here, a non‐covalent reinforcement strategy is presented by introducing a supramolecular additive to a DCN that can reversibly depolymerize and reform on demand, therefore acting as an adaptive and repairable reinforcement. The strong hydrogen‐bonding interactions in the supramolecular polymer of triazine‐1,3,5‐tribenzenecarboxamide ( S ‐ T ) strengthen the DCN at room temperature, while its non‐covalent nature allows for easy one‐pot reprocessing at high temperatures. Depending on wether S ‐ T is covalently bond to the DCN or not, it can play either the role of compatibilizer or filler, providing a synthetic tool to control the relaxation dynamics, reprocessability and mechanical properties. Moreover, the S ‐ T reinforcement can be chemically recovered with high yield and purity, showcasing the recyclability of the composite. This conceptually novel supramolecular reinforcement strategy with temperature‐controlled dynamics highlights the potential of supramolecular polymer additives to replace conventional unrepairable reinforcements.