Dynamic vacuum stability test method and investigation on vacuum thermal decomposition of HMX and CL-20

Dynamic Vacuum Stability Test (DVST) method monitoring the reaction process continuously and directly was used to investigate the thermal decomposition of HMX and CL-20. DVST employs the built-in pressure and temperature mini-sensors combined with the data acquisition-processing unit to achieve the dynamic and real-time measurement. The eligible thermal stability of HMX and CL-20 is determined by the very little amount of evolved gas. The non-isothermal reaction model of HMX varies with experimental temperature, while that of CL-20 adheres only to one. The isothermal reaction rate constants of the two samples both increase exponentially with the rise of temperature. It may be due to the accelerating autocatalysis in the solid-state thermal decomposition. DVST as an accelerated aging method was also applied to predict the storage life of materials. DVST can replace the traditional VST method in application of thermal analysis of chemicals especially energetic materials.

CL-20 is more stable than HMX under the same condition below 140 °C, while at relatively high temperature the stability of HMX is better than that of CL-20.Figure optionsDownload as PowerPoint slideHighlights
► DVST is a dynamic, continuous, direct and programmable measurement.
► CL-20 is more stable than HMX at the same condition below 140 °C.
► The reaction rate constant increases exponentially with temperature.
► The storage life of HMX and CL-20 is predicted to 90.6 a and 14.4 a.