Crystal Structures,Thermal Behavior Analysis and Thermal Safety of Two Energetic Salts of Hydrazinyl-1,2,4,5-tetrazine with 3,5-Dinitrosalicylic Acid

Two energetic salts, DPHT·DNS·H₂O(1) and DHT·2DNS·2H₂O(2)DPHT=3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-hydrazinyl-1,2,4,5-tetrazine; DHT=3,6-dihydrazinyl-1,2,4,5-tetrazine], were synthesized from S-tetrazine with 3,5-dinitrosalicylic acid(DNS). Compounds 1 and 2 were structurally characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction. The thermal behavior of the title compounds was studied by differential scanning calorimetry(DSC) and thermogravimetry(TG). The non-isothermal decomposition kinetics of compound 2 were investigated. The self-accelerating decomposition temperature, thermal ignition temperature, and critical temperatures of thermal explosion were obtained to evaluate the thermal safety of compound 2. The results show compounds 1 and 2 decompose at 150.8 and 179.2℃, respectively. The T_SADT and T_b of compound 2 are higher than those of DHT, which indicates compound 2 is a potential candidate for energetic materials that have good thermal stability.