PREPARATION AND PROPERTIES OF OCTOGEN-BASED NANOCOMPOSITE PARTICLES

An inert material, resorcinol formaldehyde (RF), was introduced to prepare octogen (HMX)-based nanocomposite particles by combining sol-gel and spray drying processes. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transformation infrared spectroscopy were used to characterize the samples. Moreover, we determined the impact sensitivity of the samples using a drop hammer apparatus and we analyzed their thermal decomposition by differential scanning calorimetry analysis. The SEM results indicated that the HMX-based nanocomposite particles were spherical in shape and ranged from 1 to 10 mu m in size. In the nanocomposite particles, the HMX nanoscale-sized particles were evenly dispersed in the RF. The XRD peaks of the composite particles were much weaker and wider than those of raw HMX. Based on Scherrer's equation, the HMX crystal size obtained from the diffraction peaks at different 2 theta ranged from 8.1 to 28.1 nm. Compared with that of raw HMX, the nanocomposite particles had lower impact sensitivity and higher detonation velocity. Moreover, the nanocomposites had a higher activation energy (E) and pre-exponential factor than raw HMX.