Ultralow-CNT-Reinforced Thermal and Mechanical Properties for Polymer-Bonded Explosives

Enhancing the thermal and mechanical properties of polymer-bonded explosives (PBXs) is critical for improving their safety and reliability. Carbon nanotubes (CNTs) are promising fillers, yet forming continuous conductive networks at ultralow loadings remains challenging. Herein, we developed a multi-level composite strategy combining water suspension and slurry methods to construct hierarchical thermal/mechanical networks with only 0.5 wt % CNTs. At 0.5 wt % CNT loading, the thermal conductivity increased by 52.09% to 0.6993 W·m –1 ·K –1, and the Brazilian splitting strength surged by 181.6%. Systematic studies on binary (CNT/F2311) and ternary (CNT/F2311/melamine) composites, supported by morphological characterization, thermal/mechanical testing, theoretical modeling, and COMSOL simulation, reveal the reinforcement mechanisms. This work provides a facile and effective approach for designing high-performance energetic composites with ultralow functional fillers.