Thermal Decomposition Kinetics of Hexanitrohexaazaisowurtzitane/Ammonium Perchlorate

Abstract

Abstract:The thermal decomposition kinetics of hexanitrohexaazaisowurtzitane/ ammonium perchlorate (HNIW/AP) have been investigated by thermogravimetrydifferential scanning calorimetry-mass spectrometry (TG-DSC-MS) simultaneous analysis. TG showed that there were three weight loss processes for the thermal decomposition of the HNIW/AP mixture. The first was ascribed mainly to the thermal decomposition of HNIW, while the second and third were assigned to that of AP. The presence of AP has little effect on the thermal decomposition process of the HNIW component. The apparent activation energy of the thermal decomposition of the HNIW component, calculated by the Kissinger method, was little changed compared to that of neat HNIW. The addition of HNIW to AP caused the onset and end temperatures of the thermal decomposition to be decreased and the decomposition process to be shortened. The high-temperature and lowtemperature decomposition processes of AP became blurred in the presence of HNIW, and this was supported by the MS results.

Determining the mechanical and decomposition properties of high energetic materials (α-RDX, β-HMX, and ε-CL-20) using a neural network potential

“…This suggests that the order of initial decomposition temperatures for α-RDX, β-HMX, and ε-CL-20 follows as β-HMX < α-RDX < ε-CL-20. However, this finding is inconsistent with the experimental observation; the initial decomposition temperature of α-RDX, β-HMX, and ε-CL-20 is 240 °C, 284 °C and 254 °C, 94–98 respectively. Notably, an underestimation of the thermal stability of β-HMX exists in this work, possibly attributed to the issues in the elastic constants (Table 3).…”

Analysis of the Thermal BehavioUr of CL-20, Potassium Perchlorate, Lithium Perchlorate and Their Admixtures by DSC and TG

“…Potassium, lithium and ammonium perchlorate (KP, LP and AP) are the oxidizers most commonly used in propellants, pyrotechnics, and PBXs, and the thermal behaviour of these oxidizers will have a significant effect on the properties of the resulting formulations. Many studies have researched the thermal decomposition of CL-20 and AP on their own and in combination [16][17][18][19]. Turcotte et al [20] examined the thermal decomposition of CL-20 at heating rates of 1 °C•min −1 , 2 °C•min −1 , 5 °C•min −1 , and 10 °C•min −1 , while the activation energy for CL-20 decomposition was determined by the Kissinger method to be 207 ±18 kJ•mol −1 ; they also determined that CL-20 loses approximately 85% of its initial mass during the decomposition.…”