Thermal decomposition kinetics and explosive properties of a mixture based on cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5-d]imidazole and 3-nitro-1,2, 4-triazol-5-one (BCHMX/NTO)

A new plastic bonded explosive mixture (PBX) based on cis-1,3,4,6-tetranitrooctahydrounidazo-[4,5-d]imidazole (BCHMX) and 3-nitro-1,2,4-triazol-5-one (NTO), bonded by polydimethylsiloxane (PDMS) binder (44/44/12 wt. %), was prepared and studied as an explosive for the Low Vulnerable Ammunition (LOVA) in comparison with the LOVA tasted composition NTO/TNT (50/50 wt%) and with analogous PBXs, filled by RDX (1,3,5-trinitro1,3,5-triazinane), beta-HMX (beta-1,3,5,7-tetranitro-1,3,5,7-tetrazocane), BCHMX and e-CL20 (e-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, e-HNIW). The mentioned PBX with the pure NTO and BCHMX, have been investigated with regard to their thermal behavior and decomposition kinetics (Kissinger and modified Kissinger-Akahira-Sunose (KAS methods) by means of the Differential Scanning Calorimetry (DSC) and Thermogravimetry (TG) techniques. Impact and friction sensitivities in addition to the measured detonation velocities and the calculated detonation characteristics (EXPLO5 code) were determined. Results of the thermoanalytical study show certain instability of PDMS binder in presence of NTO over 170 degrees C and decomposition of NTO, as a solution in degradation products of this binder in temperature region typical for thermal decomposition of BCHMX. Nevertheless, the PDMS matrix shows to be a good binder for a LOVA explosive, filled by BCHMX and NTO, due to its markedly positive effect on increasing of the resistance of this PBX against mechanical stimuli and a good thermal stability.