Energetic Boron/Glycidyl Azide Polymer/PTFE Nanocomposites for High-Performance Solid Propellant and Metal Explosives Applications

Boron is recognized as a promising fuel or fuel additive in high-energy materials owing to its exceptional gravimetric and volumetric calorific values, which is particularly well-suited for core engineering applications including high-performance composite solid rocket propellants, advanced metalized explosive formulations, and powder fuel ramjet propulsion systems. However, its practical application is severely constrained by inherent drawbacks, including a passivating surface oxide layer (B2O3) and a high boiling point, which result in difficult ignition and low combustion efficiency. To address these critical challenges, this study proposes a nanoscale boron-based B/PTFE-GAP composite microsphere system, fabricated via microfluidic technology through the synergistic modification of boron nanoparticles with the energetic binder GAP and PTFE. Computational Fluid Dynamics simulations were employed to verify the operational stability of the self-constructed microfluidic platform and the feasibility of target sample preparation, intuitively revealing the dynamic evolution mechanism of droplet accumulation-formation-detachment in the flow-focusing microchannel and ensuring the reliability of subsequent fabrication processes. Systematic characterizations were conducted to evaluate the nanoscale boron-based composite microspheres’ performance. Physical property tests demonstrated a significant enhancement in flowability. Contact angle measurements indicated improved moisture resistance. TG-DSC analysis showed that the main exothermic peak temperature advanced from 786 °C (5-B/PTFE-GAP) to 740 °C (15-B/PTFE-GAP). Combustion performance analysis revealed a notable improvement in combustion intensity. Molecular dynamics simulations confirmed the stable adsorption of GAP on B2O3 crystal surfaces, providing a structural basis for interfacial bonding. Collectively, the nanoscale boron-based B/PTFE-GAP composite microsphere system developed herein offers a strategy and technical foundation for the design and fabrication of high-performance boron-based energetic materials, with significant implications for advancing applications in aerospace propulsion and advanced weaponry systems. The as-prepared nanoscale boron-based composite microspheres can be directly applied as a high-energy metal fuel in solid propellant formulations, as a reactive energetic additive for metalized explosives, and as a core fuel component for powder fuel ramjet engines, fully meeting the application requirements of high-energy density nanomaterials in the energetic engineering field.