Synthesis of HMX/SiO₂ nanoenergetic composite and application in ignition charge

The nanoparticles of cyclotetramethylene tetranitramine (HMX) have many potential advantages, such as high energy release rate, low sensitivity, etc. Silica (SiO₂) xerogel matrix with tridimensional reticular structures, which has huge specific surface area and superior impact resistance, was taken as a template to synthesize HMX/SiO₂ nanocomposite by sol-gel method, and the loaded HMX was up to 80 wt.% of the HMX/SiO₂ nanocomposite. The structures and properties of HMX/SiO₂ nanocomposite were characterized by SEM, TEM, XRD, DSC, etc. The results revealed that the particle size of HMX in SiO₂ matrix is below 100 nm. The initial and the peak decomposition temperatures of HMX/SiO₂ nanocomposite were decreased with the increase of SiO₂ content. A new type of ignition composition containing HMX/SiO₂ nanocomposite was prepared. The results showed that the ignition composition particles are smaller than 100nm without agglomerate. Its thermal behavior was improved and mechanical sensitivities were reduced significantly, but the heat of combustion was increased properly compared with the mixture of the same components. Briefly, with the introduction of SiO₂ matrix, HMX can exist in the form of nanoparticles and the comprehensive properties of the ignition composition can be improved.