Construction of Ultra-Mixed Energetic Composite Systems by Micro Continuous Flow Coupled with Spray Drying Technology

Improving the quality of mixing between multiple components is expected to enhance the macroscopic performance of the composite energetic materials. To address the limitations associated with intermittent manual techniques in multicomponent mixing, a novel strategy that integrates microfluidic with spray drying technology was proposed to achieve the safe and continuous fabrication of ultramixed energetic composites. B/KNO3 was utilized as a representative example to validate the applicability of this strategy. This strategy allows for the simultaneous refinement of raw materials and assembly of multicomponent microscale interfaces, enabling a "one-step" synthesis approach. A microscale assembly model for composite components was constructed and applied to describe the microscopic morphology of the composite particles under different conditions. The microscopic morphology of B/KNO3 was analyzed under different component concentrations, drying temperatures, and gas flow rates to validate the applicability of the model. Based on the TG–DSC results, a qualitative explanation was provided for the relationship between the microstructural configuration of the composite system and its macroscopic thermal performance when the B/KNO3 ratio is constant. In addition, laser ignition experiments were conducted to evaluate the combustion characteristics of the ultramixed B/KNO3. Encouragingly, the quality of interfacial composite materials plays a crucial role in influencing the macroscopic reactivity, as the ultramixed B/KNO3 exhibits consistent burning rates and high delay accuracy. The proposed micro continuous flow-spray strategy not only offers novel insights into modulating the macroscopic performance of composite energetic materials through enhanced interfacial blending but also provides valuable references for the continuous fabrication of other composite materials. Moreover, this strategy prioritizes intrinsic safety aspects and effectively addresses pertinent concerns associated with the handling and processing of energetic materials.