Preparation and Characterization of the Solid Spherical HMX/F2602 by the Suspension Spray-Drying Method

Solid spherical octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine/fluororubber2602 (HMX/F-2602) was prepared by the suspension spray-drying method as follows: firstly, thinning octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) was obtained by a solvent-anti-solvent method. Secondly, thinning HMX suspended in ethyl acetate solvent in a solution of a binder-F-2602-was made into a suspension. Finally, the samples were prepared by spray drying. The samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectrometry (XPS), X-ray diffraction (XRD), and Fourier transform infrared (FTIR), and its thermal stability as well as mechanical and spark sensitivities were measured. The results of SEM showed that the grain of HMX/F-2602 was solid spherical and the particle distribution was homogeneous. The results of XPS indicated that F-2602 can be successfully coated on the surface of HMX crystals. Compared to raw HMX, th characteristic drop height was increased from 19.60 to 40.37cm, an increase of 79.10%. The friction sensitivities of HMX reduced from 100 to 28% and the spark sensitivity of HMX/F-2602 increased. The critical explosion temperatures of raw HMX and HMX/F-2602 were 275.43 and 274.30 degrees C, respectively. The amount of gas evolution of raw HMX and HMX/F-2602 was 0.15 and 0.12ml center dot(5g)(-1), respectively. The results of DSC and vacuum stability tests (VSTs) indicate that the thermal stability of HMX/F-2602 was equal to that of raw HMX and HMX and F-2602 had good compatibility.