Malleable organic/inorganic thermosetting hybrids enabled by exchangeable silyl ether interfaces

Abstract

Cross-linked elastomers are widely used in daily life; however, they become a stubborn environment problem at the end of their service life due to their thermosetting nature. Vitrimers, as a new class of materials with dynamic covalent networks that rely on associative exchange mechanisms, have been recently exploited for the development of covalently cross-linked recyclable elastomers. Herein, we report a facile strategy to achieve elastomeric vitrimers with mechanical robustness, malleability and recyclability by implementing dynamic covalent networks afforded by the interfacial silyl ether motifs in elastomer/silica hybrids. By virtue of its abundant surface silanol moieties, silica acts as both a reinforcement and cross-linker to endow the networks with chemical and mechanical robustness. Moreover, these permanent networks can reshuffle the topological structure upon temperature-induced trans-oxyalkylation reactions in the elastomer–silica interphase, enabling malleability and recyclability to the resultant materials. Since a wide variety of epoxy polymers and silanol-containing nanoparticles are easily accessible, we envisage that the present strategy can be a facile and universal avenue towards organic/inorganic hybrid vitrimers integrated with robustness, malleability and recyclability through the implementation of interfacial silyl ether-based networks.