Synthesis and thermal behavior of 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine (DDNI)

A novel energetic material, 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine (DDNI), was synthesized by the reaction of FOX-7 and glyoxal in water at 70 A degrees C. Thermal behavior of DDNI was studied with DSC and TG-DTG methods, and presents only an intense exothermic decomposition process. The apparent activation energy and pre-exponential factor of the decomposition reaction were 286.0 kJ mol(-1) and 10(31.16) s(-1), respectively. The critical temperature of thermal explosion of DDNI is 183.78 A degrees C. Specific heat capacity of DDNI was studied with micro-DSC method and theoretical calculation method, and the molar heat capacity is 217.76 J mol(-1) K(-1) at 298.15 K. The adiabatic time-to-explosion was also calculated to be a certain value between 14.54 and 16.34 s. DDNI presents lower thermal stability, for its two ortho-hydroxyl groups, and its thermal decomposition process becomes quite intense.