Abstract:Using 2-methylimidazole as raw material and dibromo methane as a bridging reagent, a bis-cationic energetic compound, 3, 3′-methylene-bis (2-methyl-1-nitroxyethylimidazolium)dinitrate(3)was synthesized via. methylene-bridging, quaternization, and nitration reactions. Then a series of bis-cationic energetic salts were obtained via the metathesis reactions of compound 3 with negative ions of picrate, dinitramide, 3, 5-dinitro-1, 2, 4-triazolate, and 5-nitrotetrazolate as anions. All the synthesized energetic salts were analyzed and characterized by ultraviolet visible spectrum(UV-Vis), infrared spectrum(IR), mass spectrum(MS), nuclear magnetic resonance(NMR), elemental analysis, and thermogravimetric analysis(TGA). The detonation peformance of the synthesized bis-cationic energetic salts, such as detonation velocity and detonation pressure, were estimated by Kamlet-Jacobs equation. Results show that the bis-cationic energetic salts have a good thermal stability, their decomposition temperatures are above 169 oC and their thermal decomposition peak temperatures are close to 200 ℃ for the first decomposition stage.The bis-cationic energetic salts apart from 5-nitrotetrazolate bis-cationic energetic salt have a better thermal stability than the corresponding mono-cationic imidazolium energetic salts. At the same time, all the bis- cationic energetic salts have a higher melting point than the corresponding mono-cationic energetic salts. Some bis-cationic imidazolium energetic salts have a higher density than the corresponding mono-cationic energetic salts. The detonation velocities and detonation pressures of 3, 3′-methylene-bis (2-methyl-1-nitroxyethylimidazolium)- di (3, 5-dinitro-1, 2, 4-triazolate)and 3, 3′-methylene- bis(2-methyl-1-nitroxyethylimidazolium)-di (5-nitrotetrazolate)are between those of 2, 4, 6-trinitrotoluene(TNT)and 1, 3, 5-trinitroperhydro-1, 3, 5-triazine(RDX), showing better detonation performances.