FOX-7 based nitrogen rich green energetic salts: Synthesis, characterization, propulsive and detonation performance

Abstract

New 1,1-diamino-2,2-dinitroethene (FOX-7)-based energetic salts are reported in this study. A variety of bases including hydrazine, hydroxylamine, ammonia, amino guanidine and metal hydroxides (MOH) were found to react with FOX-7 to give the following salts: hydrazinium (E)-2-amino-2-hydrazinylidene-1,1-dinitroethan-1-ide (1) dihydroxylammonium mono((Z)-2-amino-2-(hydroxyimino)-1,1-dinitroethan-1-ide) (2) ammonium (1-amino-2,2-dinitrovinyl)amide (3), potassium/sodium/lithium(I)-[(Z)-2-amino-2-hydrazineylidene-1,1-dinitroethan-1-ide] (4–6), and aminoguanidine-(Z)-2-amino-2-hydrazinylidene-1,1-dinitroethan-1-ide (7). The title compounds were fully characterizedusing IR, NMR, and elemental analysis. The structures of the salts 2 and 7 were further confirmed by single crystal X-ray analysis. These salts have experimental densities in the range between 1.59 gcm−3 to 1.92 g cm−3. Thermal stabilities of these salts were measured by DSC and TGA analysis and their decomposition temperatures were found between 85 °C and 177 °C. Enthalpies of formation (ΔHf°) were calculated (Gaussian 03) and with their experimental densities, the propulsive and detonation properties of the nitrogen-rich green energetic salts were evaluated. These compounds exhibit high density, high positive enthalpy (ΔHf°), balanced nitrogen and oxygen contents with excellent propulsive (Isp) and good detonation properties (DP and DV) which are superior to that of RDX, ammonium perchlorate (AP), and comparable to TKX-50. The energetic salts (1, 2, 5 and 6) show potential as highly promising secondary explosives. These energetic salts have potential as promising solid propellants.