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Three energetic ion salts of 3,6-bis[(1H-1,2,3,4-tetrazol-5-yl)-amino]-1,2,4,5-tetrazine(BTATz), namely, methylamine salt(compound 1), ethylenediamine salt(compound 2), and diethylamine salt(compound 3), were synthesized and characterized by elemental analysis, Fourier transform infrared spectrometry, 1H NMR spectroscopy, and 13C NMR spectroscopy. The crystal structure of compound 1 was determined by single-crystal X-ray crystallography, and structural analysis revealed that it belonged to the monoclinic system with P21/c space group. In addition, the thermal behavior of the three compounds was studied by differential scanning calorimetry and thermogravimetry techniques. The thermal decomposition peak temperatures of the compounds were 574.89, 545.60, and 606.72 K, indicating that the three ion salts exhibited good thermal stability. The kinetic mechanism equations of the main decomposition process and the entropy of activation(ΔS≠), enthalpy of activation(ΔH≠), and Gibbs free energy of activation(ΔG≠) of the three compounds were also obtained. Moreover, the thermal safety of the compounds was evaluated by the values of the self-accelerated decomposition temperature(TSADT), thermal ignition temperature(TTIT), and critical temperature of thermal explosion(Tb). The results showed that all the compounds demonstrated good thermal safety, and the thermal safety of compound 3 was better than that of the others.

Two novel energetic alkalic metal salts of 3,6-bis(1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine (BTATz), Li2(BTATz)·6H2O(compound 1) and Na2(BTATz)·2H2O(compound 2), have been synthesized by the reac-tion of BTATz with lithium hydroxide or sodium hydroxide in dimethylsulfoxide(DMSO) solution, respectively, and their structures were characterized by means of elemental analysis and Fourier transform infrared spectrometry(FTIR). Moreover, the single-crystal structure of compound 1 was determined by single crystal X-ray diffraction. It crystal-lizes in the monoclinic space group P1/c. Furthermore, their thermal decomposition behaviors were investigated by means of differential scanning calorimetry(DSC) and thermogravimetry-differential thermal gravimetry(TG-DTG). The results show that the exothermic decomposition peak temperatures for compounds 1 and 2 were 642.65 and 644.46 K, respectively, and the kinetic equations of the main exothermic decomposition were also derived from non-isothermal method. Additionally, the thermal safety of the two compounds was evaluated by calculating self-accelerating decomposition temperature(TSADT) and critical temperature of thermal explosion(Tb). The results(the TSADT and Tb values are 605.43 and 635.69 K for compound 1; 607.38 and 638.96 K for compound 2) reveal that the two compounds exhibit better thermal safety than BTATz.

The thermal behavior of 1,3,3-trinitroazetidine (TNAZ) is studied by means of high-pressure DSC (PDSC), the combination technique of in situ thermolysis cell with rapid-scan fourier transform infrared spectroscopy (thermolysis/RSFT-IR) and fast thermolysis probe with rapid-scan fourier transform infrared spectroscopy (fast thermolysis/RSFT-IR). The thermal decomposition mechanism is proposed. The results show that the decomposition temperature of TNAZ at 1MPa is 264.7 °C, both the C NO 2 and N NO 2 bonds and all the other C N, C C and C H bonds of the four-membered ring of TNAZ are simultaneously broken with an increase in temperature and the gas products detected of thermal decomposition of TNAZ consist of CO 2 , NO 2 , N 2 O and NO.