Thermochemical Properties, Thermal Behavior and Decomposition Mechanism of 1,1-Diamino-2,2-dinitroethylene (DADE)

The constant‐volume combustion energy, ΔcU (DADE, s, 298.15 K), the thermal behavior, and kinetics and mechanism of the exothermic decomposition reaction of 1,1‐diamino‐2,2‐dinitroethylene (DADE) have been investigated by a precise rotating bomb calorimeter, TG‐DTG, DSC, rapid‐scan fourier transform infrared (RSFT‐IR) spectroscopy and T‐jump/FTIR, respectively. The value of ΔcH⊖m (DADE, s, 298.15 K) was determined as (−8518.09± 4.59) J·g−1. Its standard enthalpy of combustion, ΔcU (DADE, s, 298.15 K), and standard enthalpy of formation, ΔfH⊖m (DADE, s, 298.15 K) were calculated to be (−1254.00±0.68) and (−103.98±0.73) kJ·mol−1, respectively. The kinetic parameters (the apparent activation energy Ea and pre‐exponential factor A) of the first exothermic decomposition reaction in a temperature‐programmed mode obtained by Kissinger′s method and Ozawa′s method, were Ek=344.35 kJ·mol−1, Ak=1034.50 s−1 and Eo=335.32 kJ·mol−1, respectively. The critical temperatures of thermal explosion of DADE were 206.98 and 207.08 °C by different methods. Information was obtained on its thermolysis detected by RSFT‐IR and T‐jump/FTIR.