Thermal Properties of Ammonium Dinitramide, Monomethylamine Nitrate and Urea based Ionic Liquid Gel Propellants

Abstract

Gel propellants have been recognized as future propulsion systems. Gel propellants are liquid fuels such as hydrazine, of which the rheological properties have been altered by the addition of gelation agents. Ammonium dinitramide (ADN) based energetic ionic-liquid propellants (EILPs) are expected to be used as replacements for hydrazine, which has high toxicity, and also for ionic liquid gel propellants (ILGPs). However, there have been few studies conducted on ADN based ILGPs. Here, ADN based ILGPs were prepared to obtain a better understanding of their thermal properties. The thermal behavior of the ADN based ILGP samples were measured using differential scanning calorimetry and the evolved gases were analyzed using thermogravimetry–differential thermal analysis with mass spectrometry. An ADN based ionic liquids (ILs) formed a gel using gelation agents of agarose and hydroxypropyl cellulose. The gas evolved from ADN based ILGPs was determined to be different from that from ADN based ILs due to reaction between the IL and the gelation agents.