Comparative study of HMX and CL-20
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This study deals with a well-known monocyclic nitramine HMX and a relatively new polycyclic strained-cage nitramine CL-20. Experimental data on the powder morphology, simultaneous thermal analysis (STA) and burning rate of binary formulations Al/HMX and Al/CL-20 are presented. Kinetic modelling for HMX and CL-20 are considered based on analysis of STA data obtained for low heating rates. The processing of STA data by the Kissinger method was shown to need to be supplemented with the construction of a thermokinetic model. The thermal decomposition of HMX is reliably described by the reaction of the first order with the autocatalysis. Obtained kinetic parameters of the HMX thermal decomposition correlate with literature-known data on kinetics of the lead stage of HMX combustion. Two types of aluminium powder, i.e. micron-sized and ultrafine, are used to investigate the interaction with both nitramines. Thermal analysis revealed the higher Al oxidation ability of the solid compounds produced at CL-20 thermolysis, than that one of HMX. Burning rate experiments show the differences in the combustion parameters between CL-20- and HMX-based formulations, specifically along with the burn rate level increase for CL-20 monopropellant as compared to HMX one, the pressure exponent and effect of the aluminium particle size variation are also distinct. Results are analyzed and compared to available literature data.
KeywordsHMX CL-20 Thermokinetic modelling Thermal analysis
Financial support of the Russian Foundation of Basic Research (RFFI grant #10-03-00317a) is gratefully acknowledged.
- 1.Nielsen AT. Synthesis of polynitropolyaza caged nitramines chemical propulsion information agency; 1987, Publication no. 473.Google Scholar
- 2.Lobbecke S, Bohn MA, Pfeil A, et al. Thermal behavior and stability of HNIW (CL 20). In: Proceedings of the 29th International Annual Conferrence on ICT, Karlsruhe; 1998. p. 145/1–145/15.Google Scholar
- 8.Leffler JE, Grunwald E. Rates and equilibria of organic reactions. New York: Wiley; 1963.Google Scholar
- 10.Muravyev N, Frolov Yu, Ordzhonikidze O, et al. Particle size and mixing technology influence on combustion of HMX/Al compositions. In: Proceedings of the 36th International Pyrotechnic Seminar, Rotterdam; 2009. p. 43.Google Scholar
- 11.Bulusu S, Behrens RA. Review of the thermal decomposition pathways in RDX, HMX and other closely related cyclic nitramines. Def Sci J. 1996;46(5):347–60.Google Scholar
- 13.Melius SF. Thermochemical modeling: II. Application to ignition and combustion of energetic materials. In: Bulusu S, editor. Chemistry and physics of energetic materials. Boston: Kluwer; 1990. p. 51–78.Google Scholar
- 21.Zeldovich YB. Theory of combustion of propellants and explosives. Zh Eksp Teor Fiz. 1942;12(11–12):498–524.Google Scholar
- 22.Sinditskii VP, Egorshev VY, Berezin MV, et al. Study on combustion of energetic cyclic nitramines. Zh Khim Fiz. 2003;22(7):64–9.Google Scholar