Liquid Azide Salts and Their Reactions with Common Oxidizers IRFNA and N₂O₄

Abstract

Several imidazolium-based ionic liquid azides with saturated and unsaturated side chains were prepared, and their physical and structural properties were investigated. The reactivity of these new as well as some previously reported ionic liquid azides with strong oxidizers, N 2O 4 and inhibited, red-fuming-nitric acid (IRFNA), was studied.

Fourier Transform Infrared Studies in Hypergolic Ignition of Ionic Liquids

“…The initial heat release from the N 3 -ion decomposition to form N 2 and N 2 O is not sufficient in our tests to further decompose the heterocyclic countercation to cause ignition, even when (partial) oxidation of the cation may concurrently contribute to the heat release. 44 …”

“…These cations may be paired with oxygen-containing anions (NO 3 -) for oxygen balance or high heats of formation (N 3 -) to promote hypergolic ignition when treated with a suitable oxidizer. 44 The discovery that the anion can play a critical role in inducing hypergolicity is described here. The fact that a common anion can induce hypergolicity when paired with numerous different cations to form ionic liquids allows for the tailoring of the cation for various desirable properties such as high heat of formation, low viscosity, a wide liquid temperature range, environmental safety, and thermal and shock stability.…”

Azetidinium‐based Hypergolic Ionic Liquids with High Strain Energy

“…[7] This provided an opportunity to replace the toxic hydrazine derivatives with green bipropellant fuels. Since then, attentions have been increasingly paid to ILs due to their characteristics, such as negligible vapor pressure, high thermal stability, low toxicity, [2,[8][9][10] Currently, many studies focus on the design of ILs with good hypergolicity and fluidity, including cations such as alkyl-substituted imidazolium, triazolium, pyrrolidinium, pyridinium, [11,12] and anions such as N(CN) 2 À , [13] BH 4 À , [14,15] BH 3 CN À , [16][17][18] BH 2 (CN) 2 À , [19] N 3 À , [20][21][22] …”

Synthesis and Improved Properties of Hypergolic Boronium‐Based Ionic Liquids

“…As such, much attention has recently been paid to ionic liquids (ILs) owing to the promising advantages of low vapor pressure, low toxicity, low phase transition temperature and high thermal stability. [3][4][5][6] Since the first hypergolic IL (HIL) family of dicyanamide salt was reported by Schneider et al, [7] the chemistry of HIL has been rapidly developed with several series, including the nitrocyanamideanion based ILs, [8] azide-functionalized liquid salts, [9][10][11] dialkyltriazanium-based ILs, [12] [Al(BH 4 …”