Fourier Transform Infrared Studies in Hypergolic Ignition of Ionic Liquids

Abstract

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Generation of Melamine Polymer Condensates upon Hypergolic Ignition of Dicyanamide Ionic Liquids

“…[4] Since 2008, a number of ILs have been reported to be hypergolic when treated with common oxidizers, such as HNO 3 . [5][6][7] Of particular practical interest are hypergolic ILs comprising fuel-rich dicyanamide (DCA) anions. [5] The DCA ILs have some of the lowest viscosities among known ILs, [8] which is a very important figure of merit for the efficient fuel supply in bipropellant engines.…”

“…The concurrent formation of precipitate siphons materials from the hypergolic reaction pathway, [6] thus limiting the energy capacity of a fuel. Our rough measurements indicate that about 25% of DCA IL is converted into precipitate during the ignition.…”

Chemical Kinetics Interpretation of Hypergolicity of Ionic Liquid-Based Systems

“…After a general introduction on the interesting results recently observed in this field by Chambreau and Vaghjiani et al (2008) at the Air Force Research Laboratory (AFRL), Edwards AFB, this report will discuss the thermochemistry of imidazoles, triazoles, tetrazoles, and nitro compounds, which are energetic compounds for which relatively little thermodynamic data is available. Then, the reactivity of the gas phase above the reacting ILs-WFNA liquid mixtures will be examined by performing calculations at thermodynamic equilibrium as described in interim report # 2.…”

“…Actually, Chambreau and Vaghjiani et al (2008) showed that ILs and WFNA react exothermically in the liquid phase to form products in the liquid phase that then elute into the gas phase. This is further discussed in section 5.…”

“…The answer is necessarily yes, because ignition is experimentally observed (Chambreau and Vaghjiani et al (2008) The adiabatic flame temperature at constant pressure is about 2500 K. This indicates that such a system is able to sustain a flame.…”