Thermal decomposition of mechanoactivated ammonium perchlorate

Abstract

The regimes of non-explosive mechanical treatment of ammonium perchlorate (AP) in high-energy intensity planetary ball mill are found. The changes in the structure and reactivity of AP as a result of mechanical processing were studied by methods of synchronous thermal analysis with registration of mass spectra, x-ray diffraction, microscopy and elemental analysis. Mechanical treatment reduces the particle size from 1000 μm to a fraction of μm and leads to formation of agglomerates of submicron particles with sizes of 5–10 μm. X-ray diffraction analysis shows the absence of the formation of new phases and a substantial broadening of the diffraction lines. As a result of mechanical activation, the temperature of AP thermal decomposition decreases by more than 100 °C, accompanied by the rapid release of oxygen at temperatures of 250–260 °C, immediately after the phase transformation in AP. The results obtained make it possible to explain the phenomenon of a significant increase in the detonation ability of mechanically activated AP and its mixtures with Al.