Research On Surface Coating Technology Of HMX And Its Performances

HMX has been widely used in military applications, especially in the explosive charge, the application of the solid propellant and the propellant, etc. because of its high density, high detonation velocity and good heat resistance and many other advantages. But the high mechanical sensitivity and shock wave sensitivity of HMX, make it can’t meet the requirements of IM. Therefore, HMX need to be taken some appropriate measures and methods to reduce its mechanical sensitivity, thus increasing the universality of application and security.In this paper, the BAMO-THF copolyether/HMX composite particles were obtained using BAMO-THF copolyether as binder, toluene2,4-diisocyanate (TDI) as the firming agent, and adding DOS as plasticiser, MAPO as cross linker by in situ crystallization coating modification method. In this process, dimethyl sulfoxide and butyrolactone were used as solvent respectively. And then the influence of experimental conditions on the HMX composite particles was discussed such as the kinds of solvent, temperature, the way of adding non-solvent and its drop acceleration, ultrasound and the difference of surfactant, etc.Then the optimal experimental conditions were obtained, according to the discussion of experimental conditions. The better BAMO-THF/HMX composite particles were obtained with the presence of ultrasonic, hexadecyl trimethyl ammonium bromide as surfactant, the positive addition at the rate of1d/s to the mixed solvent.The HMX composite particles were analyzed by using X-ray powder diffraction (XRD), scanning electron microscope (SEM), infrared spectrometer, impact sensitivity and friction sensitivity. The results show that the HMX composite particles are still β-crystal shape. The surface of HMX was coated by nitrogen containing polyurethane material, with better morphology, no significant edges and corners, uniform particle size distribution, good viscosity, the phenomenon of unbonded reunion, no particl agglomeration and significantly lower mechanical sensitivity_Its impact sensitivity and friction sensitivity reduce from88%and92%of original HMX to24%and40%respectively The in situ crystallization coating method played a very good eduction of mechanical sensitivity.