Electrospray-engineered Al/PTFE/NC microspheres with self-reactive 3D thermal-conductive networks for enhanced combustion performance

Aluminum/polytetrafluoroethylene (Al/PTFE) exhibits significant application potential as a high-energy additive in energetic materials. However, its utilization is limited by the native aluminum oxide shell on aluminum surfaces and inefficient mass/heat transfer between Al and PTFE, which substantially impair combustion kinetics and energy release efficiency. To address this, we employed electrostatic spray technology with Nitrocellulose (NC) as a binder to fabricate composite microspheres featuring self-reactive 3D thermal-conductive networks. These microspheres demonstrate enhanced energy release and combustion reactivity. Systematic characterization of Al/PTFE/NC composites through open- and closed-space combustion tests revealed superior energy output characteristics attributed to their internal 3D networks. Compared to physically mixed counterparts, the composites exhibit significantly improved combustion pressure (3.64 ×), pressurization rate (5.91 ×), and combustion velocity (1.61 ×). Furthermore, parametric studies established that 5 wt% NC content and an Al/F ratio of 4:6 yield optimal combustion performance. This work demonstrates that energetic-fiber-constructed 3D networks enhance intra-particle mass/heat transfer, enabling efficient combustion of Al/PTFE composites and providing strategic guidance for their advanced applications.