Estimation of Critical Temperature of Thermal Explosion for Nitrosubstituted Azetidines Using Non-isothermal DSC

Based on reasonable hypothesis, two general expressions and their six derived formulae for estimating the critical temperature (Tb) of thermal explosion for energetic materials (EM) were derived from the Semenov's thermal explosion theory and eight non‐isothermal kinetic equations. We can easily obtain the values of the initial temperature (T0i) at which DSC curve deviates from the baseline of the non‐isothermal DSC curve of EM, the onset temperature (Tei), the exothermic decomposition reaction kinetic parameters and the values of T00 and Te0 from the equation T0i or ei=T00 or e0+a1βi+a2βi2+···+aL−2βiL−2, i=1, 2, ;···, L and then calculate the values of Tb by the six derived formulae. The Tb values for seven nitrosubstituted azetidines, 3,3‐dinitroazetidinium nitrate (1), 3,3‐dinitroazetidinium picrate (2), 3,3‐dinitroazetidinium‐3‐nitro‐1,2,4‐triazol‐5‐onate (3), 1,3‐bis(3′,3′‐dinitroazetidine group)‐2,2‐dinitropropane (4), 1‐(2′,2′,2′‐trinitroethyl)‐3,3‐dinitroazetidine (5), 3,3‐dinitroazetidinium perchlorate (6) and 1‐(3′,3′‐dinitroazetidineyl)‐2,2‐dinitropropane (7), obtained with the six derived formulae are agreeable to each other, whose differences are within 1.5%. The results indicate that the heat‐resistance stability of the seven nitrosubstituted azetidines decreases in the order 6>7>5>4>3>2>1. Two general expressions, six derived formulae and their numerical methods for estimating the critical temperature (Tb) of thermal explosion for energetic materials (EMs) are presented. The values of Tb for seven nitrosubstituted azetidines are calculated.