Thermal behavior of new oxidizer ammonium dinitramide
- 528 Downloads
Ammonium dinitramide (ADN) is a promising new oxidizer for solid propellants because of its high oxygen balance and high energy content, and halogen-free combustion products. One of the characteristics needed for solid propellants is stability. Heat, light, and moisture are factors affecting stability during storage, manufacture, and use. For practical use of ADN as a solid propellant, clarification of the mechanism of decomposition by these factors is needed to be able to predict lifetime. This study focused on thermal decomposition of ADN. Exothermal behavior of ADN decomposition was measured by isothermal tests using high-sensitive calorimetry (TAM) and non-isothermal tests using differential scanning calorimetry (DSC). Based on these results, analysis of the decomposition kinetics was conducted. The activation energy determined by TAM tests was lower than that from DSC tests. Thus, the decomposition path in TAM tests was different from that in DSC tests. The amount of ADN decomposition predicted from TAM tests was closer to that found under real storage conditions than the amount of decomposition predicted from DSC tests. Non-isothermal tests may not be able to precisely predict the lifetime of materials with a decomposition mechanism that changes with temperature, such as ADN. The lifetime predicted from DSC results was much longer than that from TAM tests especially at low temperature. It is necessary to use isothermal tests to predict the long-term stability at low temperature.
KeywordsAging Ammonium dinitramide Thermal decomposition Lifetime prediction
The authors are grateful to Dr. Yuji Wada and Dr. Yusuke Wada of National Institute of Advanced Industrial Science and Technology of Japan for their fruitful discussions, and also to Hosoya Pyro-Engineering Co., Ltd. for providing samples.
- 4.Okamoto K, Kohga M, Hasue K. Thermal behavior and tensile property of PTHF/HTPB blend. Sci Technol Energ Mater. 2009;70:87–93.Google Scholar
- 5.Wada Y, Seike Y, Tsuboi N, Hasegawa K, Kobayashi K, Nishioka M, Hori K. Combustion mechanism of tetra-ol glycidyl azide polymer. Sci Technol Energ Mater. 2008;69:143–8.Google Scholar
- 13.Bottaro JC, Schmidt RJ, Penwell PE, Ross DS. World Intellectual Property Organization, International Application Number PCT/US91/04268, Dec 26, 1991.Google Scholar
- 15.Pak Z. Some ways to higher environmental safety of solid rocket propellant application. In: Proceedings of the AIAA/SAE/AS-MEASEE 29th Joint Propulsion Conf and Exhibition. Monterey, CA; 1993.Google Scholar
- 16.Matsunaga H, Yoshino S, Kumasaki M, Habu H, Miyake A. Aging characteristics of the energetic oxidizer ammonium dinitramide. Sci Technol Energ Mater. 2011;72:131–5.Google Scholar
- 26.Advanced Kinetics and Technology Solutions, AKTS-Thermokinetics Software and AKTS-Thermal Safety Software. http://www.akts.com. Accessed 8 March 2012.
- 28.Friedman HL. Kinetics of thermal degradation of char-forming plastics from thermogravimetry. Application to a phenolic plastic. J Polym Sci Part C. 1963;6:183–95.Google Scholar
- 29.Ozawa T. Applicability of Friedman plot. J Therm Anal. 1986;31:546–51.Google Scholar
- 31.Russell TP, Stern AG, Koppes WM, Bedford CD. Thermal decomposition and stabilization of ammonium dinitramide. In: Proceedings of 29th JANNAF combustion subcommittee meeting. 1990; 593-II:339–345.Google Scholar
- 32.Gordon S, McBride BJ. Computer program for calculation of complex chemical equilibrium compositions and applications. Washington, DC: NASA Reference Publication 1311; 1996.Google Scholar