Thermal properties of CL-20/HMX-Am-GO composites

The thermal decomposition of Hexanitrohexaazaisowurtzitane CL-20/HMX-ammonium formate functionalized graphene oxide (Am-GO) composites was studied using an isothermal decomposition dynamics research instrument to explore the effects of Am-GO on the stability of CL-20/HMX co-crystal. The gas pressure-time curve generated by thermal decomposition reaches the decomposition inflection point at a decomposition degree of 85 %. Compared with CL-20/HMX co-crystal, the decomposition extent corresponding to the inflection point of the thermal decomposition curve of the composites increases. The activation energies of the composites before and after the inflection point of the pressure-time curve were 161.3 kJ/mol and 171.0 kJ/mol, respectively. The residual substances produced by the thermal decomposition of the composites were characterized by HPLC and FTIR. Results showed that CL-20 and HMX were decomposed before the inflection point of the decomposition pressure-time curve. However, the decomposition of CL-20 was completed before the inflection point, whereas that of HMX ran through the thermal decomposition process. The calculation results of thermal decomposition kinetics show that the addition of coating material increases the activation energy of co-crystal and stabilizes CL-20/HMX co-crystal.