Thermal Decomposition of HMX and Mixtures

Thermal decomposition of pure HMX shows DSC endothermic peaks at 210°C from β to γ phase transformation and at 285°C from the HMX melting followed by an instantaneous exothermic decomposition leading to a strong peak at 290°C and a very strong DTG peak at 325°C with a mass loss of 95%. However, the GS‐2 mixture shows two DSC exothermic peaks at 225°C and 270°C assigned to nitroguanidine etc. and HMX decomposition. Addition of NH 4 ClO 4 to HMX causes the decomposition to take place before melting and decomposition peak is lowered to 230°C. However in the case of GS‐2, a strong effect was observed and the amount of the mixture was to be decreased to obtain a reasonable DSC curve. This shows that the addition of NH 4 CIO 4 to HMX increases the decomposition of HMX, however this effect is more pronounced in GS‐2 mixture. Even the minimum concentration of NH 4 CIO 4 tested (10%) shows strong effect. The addition of NH 4 NO 3 to HMX and GS‐2 shows DSC exothermic decomposition peaks at 272°C and 245°C, showing a contribution from NH 4 NO 3 decomposes near to the decomposition of HMX, it does not show a strong effect on the decomposition of HMX/GS‐2 as compared to NH 4 ClO 4 . Addition of KClO 4 , NaClO 4 and KNO 3 don't show any effect in these thermoanalytical studies.