Dynamic amine terminated hyperbranched polyamide for high performance epoxy network

Abstract Traditional epoxy thermosets cannot be reprocessed or recycled due to their permanent covalent cross-linking network. Covalent adaptable networks (CANs) emerge as a solution, endowing epoxy thermosets with recyclability, reprocessability and self-healing ability to tackle the recycling issue. Nevertheless, the existing covalent adaptable epoxy network exhibits low mechanical robustness, glass transition temperature and thermal stability. Herein, we have developed a covalent adaptable epoxy network based on dynamic amine terminated hyperbranched polyamide (AHPA) to fabricate catalyst-free and high-performance epoxy vitrimers. The incorporation of thermoactivated rearrangement of AHPA enables the obtained epoxy vitrimers to possess remarkable reprocessability, along with good thermal stability, high glass transition temperature and excellent creep resistance. The epoxy vitrimers can be easily reprocessed without compromising thermal and mechanical properties even after multiple cycles, presenting a promising design of dynamic hyperbranched polymers for constructing adaptive and recyclable epoxy thermosets for sustainable engineering applications.