Preparation of ultrafine FOX-7 using high-pressure microfluidization technology and study on its properties

To regulate the particle size and improve the morphology of FOX-7, high-pressure microfluidization technology was employed for refinement. The effects of key processing parameters, including jet pressure, processing cycles, the mass ratio of FOX-7 to liquid medium, and liquid medium type, on particle size and morphology were systematically investigated. The optimized conditions were determined as a jet pressure of 138 MPa, 60 cycles, a FOX-7-to-liquid-medium mass ratio of 1:10, and H2O as the liquid medium. Under these conditions, the refined FOX-7 exhibited a regular morphology and a median particle size of 1.464 μm. Structural characterization confirmed that the refined FOX-7 retained the α-type crystal structure of the raw material. Compared with the raw FOX-7, the refined sample showed enhanced thermal stability, improved energy release efficiency, and reduced mechanical sensitivity. These results demonstrate that high-pressure microfluidization is an effective method for controlling particle size and improving the comprehensive properties of FOX-7.