Synthesis and Characterization of Tetramethylethylenediamine-Based Hypergolic Ionic Liquids

Four energetic salts (including two ionic liquids) based on 2-(dimethylamino)-N,N,N-trimethylethanaminium and N,N-dialkyl-N,N,N,N-tetramethylethane-1,2-diaminium was prepared and characterized by H-1- and C-13-NMR, infrared and Raman spectroscopies, and elemental analysis. Their physicochemical properties such as melting and decomposition temperatures, density, viscosity, heat of formation, detonation performance, and specific impulse were measured or calculated. With thermal stability up to 200 degrees C, the resulting ionic liquids show densities from 1.02 to 1.19 g cm(-3) and heats of formation from 85.1 to 154.4 kJ mol(-1). Moreover, 2-(dimethylamino)-N,N,N-trimethylethanaminium dicyanamide is hypergolic with the oxidizer (100% HNO3) and exhibits potential as a green fuel for bipropellants.