Thermal decomposition and combustion of cocrystals of CL-20 and linear nitramines

The thermal decomposition and combustion behavior of the bimolecular cocrystals of 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (CL-20) with linear nitramines 2,4-dinitro-2,4-diazapentane (DNP) and 3,5-dinitro-3,5-diazaheptane (DNG) were studied. Being more volatile than CL-20, the linear nitramines have been shown to evaporate first at heating, leaving CL-20 in the amorphous form. The loss of the crystal lattice is a reason for the increased rate of CL-20 decomposition observed, which is comparable to the decomposition rate of CL-20 in the liquid phase. Different volatilities of linear nitramines and CL-20 caused the heat release zones to be spatially separated in the combustion wave of the co-crystals. Considering the lower energetic characteristics of the linear nitramines as compared to CL-20, they play the role of the diluents in the combustion wave.