A Kinetics Investigation on the Nitro-Nitrite Rearrangement Mediated Thermal Decomposition of High Temperature Monoclinic Phase of 1,1-Diamino-2,2-Dinitroethylene (γ-Fox-7)

Abstract

1,1-Diamino-2,2-dinitroethylene (DADNE), commonly known as FOX-7, is one of the novel high energy density molecules recently developed along with CL-20, TNAZ and ADN. DADNE is well-known for its insensitive nature and this has motivated the research in understanding the thermal and explosive decomposition behaviour of DADNE. We have studied the thermal decomposition kinetics of DADNE employing two isoconversional methods viz., Friedman’s differential method and Vyazovkin’s non-linear integral method. For the study, Differential Scanning Calorimetry as well as Thermogravimetry data collected at lower heating rates (<5°C/min) were used. This study indicated a four stage decomposition behaviour of DADNE, where each stage is characterised by different activation energy. Computed activation energy values have been used to understand the thermal decomposition mechanism of DADNE. Experimental investigations of thermal decomposition kinetics of 1,1-Diamino-2,2-Dinitroethylene (γ-Fox-7), DADNE at a lower heating rate was studied using Differential Scanning Calorimetry and Thermogravimetry. The results suggest that DADNE exhibits two different decomposition pathways. During thermogravimetric analysis it undergoes nitronitrite rearrangement-mediated decomposition leading to the formation of CO, H2O and N2.