Microchannel nano-boron based microspheres as an effective enhancer on performance of ADN/DAP-4 oxidizer

Utilizing micro-channel technology and meticulously regulating the differential flow rates of the oil and water phases, we successfully synthesized remarkably spherical nB/F 2602 /HNS (hexanitrostilben)microspheres, measuring approximately 200 μm in diameter. The morphological and compositional characteristics of these microspheres were thoroughly analyzed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), and laser microscopy. Meanwhile, we conducted an in-depth investigation into the catalytic effects of the microspheres on the thermal decomposition of ADN(Ammonium dinitramide)/DAP-4((C 6 H 14 N 2 )[NH4(ClO 4 ) 3 ]), employing thermogravimetric-differential scanning calorimetry (TG-DSC) and burst point assessments. The combustion performance of ADN/DAP-4, both prior to and following the incorporation of nB/F 2602 (fluoroelastomer)/HNS microspheres, was evaluated through high-speed imaging, high-sensitivity infrared thermography, and combustion calorimetry measurements. Furthermore, this study contemplated the combustion mechanism of nB/F 2602 /HNS microspheres. The findings indicated that, after adding nB/F 2602 /HNS microspheres, the thermal decomposition activation energy of ADN/DAP-4 was significantly reduced. These results revealed that the introduction of nB/F 2602 /HNS microspheres markedly enhanced the combustion intensity of ADN/DAP-4, with the pressurization rate accelerating dramatically from 0.55 MPa/s to 3.47 MPa/s. As the burning rate escalated, the maximum combustion temperature increased from 1697°C to 1788°C, and the combustion heat surged from −4478 kJ/kg to −17593 kJ/kg. Moreover, the comparative experimental outcomes, when juxtaposed with samples based on micro-boron (μB), reveal that nano-boron (nB) exhibits a superior burning rate and combustion efficiency. Consequently, the collective findings of these experiments emphatically indicate that nB/F 2602 /HNS markedly enhances the thermolytic and combustion processes of ADN/DAP-4.