Thermal Behavior of 2‐(Dinitromethylene)‐1,3‐diazacyclopentane

A new compound, 2-(dinitromethylene)-1,3-diazacyclopentane (DNDZ), was prepared by the reaction of 1,1-diamino-2,2-dinitroethylene (FOX-7) with 1,2-diaminoethane in N-methylpyrrolidone (NMP). Thermal decomposition of DNDZ was studied under non-isothermal conditions by DSC, TG/DTG methods, and the enthalpy, apparent activation energy and pre-exponential factor of the exothermic decomposition reaction were obtained as 317.13 kJ·mol−1, 269.7 kJ·mol−1 and 1024.51 s−1, respectively. The critical temperature of thermal explosion was 261.04°C. Specific heat capacity of DNDZ was determined with a micro-DSC method and a theoretical calculation method, and the molar heat capacity was 205.41 J·mol−1·K−1 at 298.15 K. Adiabatic time-to-explosion was calculated to be a certain value between 263–289 s. DNDZ has higher thermal stability than FOX-7.