Thermal Stability, Kinetic Triplet Study and Sensitivity Evaluation of Composite Explosive of 1,3,5,7-Tetranitro-1,3,5,7-tetrazocane (HMX) and Nitro-1,2,4-triazol-5-one (NTO)

A composite explosive including HMX and NTO is prepared by precipitation procedure in acetone solvent. 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) is a powerful explosive but sensitive to external stimuli. While, nitro-1,2,4-triazol-5-one (NTO) is a relatively strong explosive with lower sensitivity in comparison to HMX. The prepared composite explosive of HMX/NTO is characterized using XRD patterns and FT-IR spectra which show a minor change in the molecular structure of precursors. Thermal stability of HMX/NTO composite is investigated by study of DSC curves at various heating rates. Activation energy (Ea) of thermal decomposition reaction of HMX, NTO and HMX/NTO are obtained, 414.7, 402.6 and 435.2 kJ mol–1, respectively, by iso-conversional method of KAS which indicates more stability of HMX/NTO composite against thermal decomposition. Also, the Avrami–Erofeev equations of A3/2, A3/2, and A3 describe the thermal degradation mechanism of HMX/NTO composite, raw HMX and raw NTO, respectively. The sensitivity to impact, friction and electrostatic discharge of HMX, NTO and HMX/NTO are studied in accordance to the standards of STANAG no. 4489, STANAG no. 4487, and STANAG no. 4490, respectively, using methods of Bundesamt für Materialforschung (BAM). The results of external stimuli are also showed the less sensitivity of HMX/NTO composite in comparison to HMX and, thus, it is a candidate for insensitive munitions (IM).