Nanoscale interfacial reinforcement of highly filled composites constructed by a self-healing energetic polymer with triple dynamic bonds

Designing highly filled energetic composites with minimal micro-interface defects remains a persistent challenge in the aerospace field. Herein, we constructed a room-temperature self-healing energetic polymer by the triple dynamic bonds, which include azido-azido dipolar interaction, aromatic diselenide bonds, and multilevel hydrogen bonds. Controlling these dynamic bonds could influence the intermolecular interactions, microphase separation, and the mobility of polymer segments. As a result, the optimal polymer exhibited excellent mechanical toughness (13.17 MJ/m 3 ), room-temperature healing capacity (91.65 % after 48 h), and high heat release (1197.62 J/g). To confirm the applicability, the energetic composites with 70 wt% solid content were fabricated by shear calendar technology. Thanks to the nanometer-scale interface interaction, the toughness of nanoscale Al-based composites was enhanced by 94.5 % compared to that of their micron Al-based counterpart. Importantly, this method enables the composites to attain effective crack healing at safe temperatures. The present study presents a feasible method to design the safe solid propellant for aerospace applications.