One-step synthesis of polynitropyridine-based thermostable and low sensitive energetic materials
Qian Wang, Caijin Lei, Hongwei Yang, Guangbin Cheng
Abstract
In this study, two energetic compounds based on a 3,5-dinitropyridine backbone linked by hydrazine and imine bridges were synthesized and fully characterized using elemental analysis, NMR (1H, 13C), IR, and differential scanning calorimentry (DSC). The crystal structures of 1,2-bis(3,5-dinitropyridin-2-yl)hydrazine (2) and N-(3,5-dinitropyridin-2-yl)-6,8-dinitro-[1,2,4]triazolo[1,5-a]pyridine-2-amine (3) were further determined using X-ray diffraction. Compounds 2 and 3 possess high thermal stability, with Td of 274 °C and 290 °C, respectively, both of which are higher than 250 °C. In addition, both compounds have desirable insensitive properties IS > 40 J, FS > 360 N) and are more insensitive than HNS and PYX (HNS: IS = 5 J, FS = 240 N; PYX: IS = 10 J, FS = 360 N). Moreover, the detonation properties of compounds 2 and 3 (2: vD = 7862 m·s−1, p = 25.4 GPa; 3: vD = 8024 m·s−1, p = 26.9 GPa) are both higher than that of HNS (vD = 7612 m·s−1, p = 24.3 GPa). These results indicate that both compounds have promising prospects as thermostable and insensitive explosives.