Further Decomposition Pathways of Mixtures of the Nitramines HMX, RDX and CL20 with the Energetic Binder Glycidyl Azide Polymer (GAP) - A Computational Study II

• Autorzy: Bohn, M. A. , Hammerl, A. , Harris, K. , Klapötke, T. M.
• Języki publikacji: EN

Abstrakty

EN

The energetic plasticizer glycidyl azide polymer (GAP) is used for new types of rocket propellants which are formulated with the objective of achieving higher burning rates. While the homolytic fission of an N-NO2 bond, which we discussed previously, is energetically favored as the initial decomposition step, experiments show that the decomposition of mixtures of the nitramines octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and hexanitrohexaazaisowurtzitane (CL20) with a monomer of GAP-diol is more complex. Therefore we investigated further possible decomposition pathways. Comparison of the calculated activation energies for the decomposition of the mixtures with those for the decomposition of the isolated nitramines shows that the presence of GAP-dioldecreases the activation energies of certain decomposition steps by up to 20 kJ mol-1. GAP-diol facilitates the decomposition of CL20 and RDX to a larger extent than the decomposition of HMX. However, the investigated decomposition pathways of GAP-diolwere inhibited by the presence of the nitramines.

Słowa kluczowe

EN

calculation; decomposition; energetic binder; nitramine; solid rocket propellant

• Czasopismo: Central European Journal of Energetic Materials
• Rocznik: 2005
• Tom: Vol. 2, nr 3
• Strony: 3-19
• Opis fizyczny: Bibliogr. 26 poz.

Twórcy

autor

Bohn, M. A.

• Fraunhofer Institut für Chemische Technologie, Energetic Materials Stability, Joseph-von-Fraunhofer-Str. 7, D-76327 Pfinztal (Berghausen), Germany

autor

Hammerl, A.

• Department of Chemistry and Biochemistry, Ludwig-Maximilians Universitdt Miinchen (LMU), Butenandtstr. 5-13 (D), D-81377 Miinchen, Germany

autor

Harris, K.

• Department of Chemistry and Biochemistry, Ludwig-Maximilians Universitdt Miinchen (LMU), Butenandtstr. 5-13 (D), D-81377 Miinchen, Germany

autor

Klapötke, T. M.

• Department of Chemistry and Biochemistry, Ludwig-Maximilians Universitdt Miinchen (LMU), Butenandtstr. 5-13 (D), D-81377 Miinchen, Germany,

Bibliografia

• [1] Bohn M. A, Dorich M., Aniol l, Pontius H., Gerber P., Reactivity between E-CL20-GAP and j3-HMX-GAP Investigated by Mass Loss, Adiabatic self-Heating and Dynamie Mechanical analysis., Proc. 1nt. Pyrotechnics Seminar 2004, 31st, Fort Collins,Colorado, USA, 11-16.07.2004.
• [2] Bohn M. A, Thermal Ageing of Rocket Propellant Formulations Containing epsilon-HNIW (epsilon-CL20) Investigated by Heat Generation Rate and Mass Loss., Thermochim. Acta, 2003, 401, 27-4 l.
• [3] Bohn M. A, Kempa P. B., Thome V, Exploring ofInteractions between the Nitramines RDX, HMX, CL20 and Components in F ormulations by Computer Simulation, 1nt. Annu. Conf 1CT Energetic Materials - Analysis, Diagnostics and Testing 2000, sr; 63/1-63/19; 27 - 30.6.2000.
• [4] Bohn M. A, Hammerl A, Harris K., KlapotkeT. M., The Elimination of 'N02 from Mixtures of the Nitramines HMX, RDX and CL20 with the Energetic Binder Glycidyl Azide Polymer(GAP)-AComputational Study I, Centr. Europ. JEnerg. Mater., 2(2), 29-44.
• [5] Oyumi Y., Thermal Decomposition of Azide Polymers., Propellants, Explos. Pyrotech., 1992, 17,226-231.
• [6] Oyumi Y., Brill T B., Thermal Decomposition of Energetic Materials. 12. Infrared Spectral and Rapid Thermolysis Studies of Azide-containing Monomers and Polymers, Combust. Flame, 1986, 65,127-135.
• [7] Chen l K, BrilI T B., Thermal Decomposition of Energetic Materiais. 54. Kinetics and Ear-surface Products ofAzide PolymersAMMO, BAMO, and GAP in Simulated Combustion, Combust. Flame, 1991, 87,157-168.
• [8] Bock H., Dammel R., Gas Phase Reactions. Part 66. Essay on Molecular Properties and Models. Part 15. Pyrolysis of Azides in the Gas Phase, Angew. Chem., 1987, 99,518-40.
• [9] Fazlyodlu H., Hacalodlu l, Thermal Decomposition of GlycidylAzide Polymer by Direct Insertion Probe Mass Spectrometry, J Anal. Appl. Pyrol., 2002, 63,327-338.
• [10] Korobeinichev O. P., Kuibida L. V, Volkov E. N., Shmakov A G., Mass Spectrometric Study of Combustion and Thermal Decomposition of GAP, Combust. Flame, 2002, 129,136-150.
• [11] Farber M., Harris S. P., Srivastava R D., Mass Spectrometric Kinetic Studies on Several Azido Polymers, Combust. Flame, 1984, 55, 203-21 l.
• [12] Chakraborty D., MulIer RP., Dasgupta S., Goddard III W. A, Mechanism for Unirnolecular Decomposition of HMX (1,3,5,7 - Tetranitro-l ,3,5,7 -tetrazocine), an ab Initio Study,J Phys. Chem. A, 2001, 105,1302-1314.
• [13] Chakraborty D., MulIer R. P., Dasgupta S., Goddard III W. A., The Mechanism for Unimolecular Decomposition of RDX (l,3,5-Trinitro-l,3,5-triazine), an ab Initio Study, J Phys. Chem. A, 2000, 104,2261-2272.
• [14] Bulusu S., Weinstein D. 1., Autera J. R., Velicky R W., Deuterium Kinetic Isotope Effect in the Thermal Decomposition of 1 ,3,5- Trinitro-l ,3,5-triazacyclohexane and 1,3,5,7 - Tetranitro-l ,3,5,7 -tetraazacyclooctane: its Use as an Experirnental Probe for their Shock-induced Chemistry,J Phys. Chem., 1986,90,4121-4126.
• [15] Behrens R Jr., Bulusu S., Thermal Decomposition ofEnergetic Materials. 2. Deuterium Isotope Effects and Isotopie Scrambling in Condensed-phase Decomposition of Octahydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine,J Phys. Chem., 1991, 95, 5838-5845.
• [16] Lewis J. P., GlaesemannK. R, Van Opdorp K, Voth G. A,Ab Initio Calculations of Reactive Pathways for a-Octahydro-l ,3,5,7 -tetranitro-l ,3,5,7 -tetrazocine (a-HMX), J Phys. Chem. A, 2000,104,11384-11389.
• [17] Harris N. J., Lammertsma K, Ab Initio Density Functional Computations of Conformations and Bond Dissociation Energies for Hexahydro-l,3 ,5-trinitro-l ,3,5-triazine,J Am. Chem. Soc., 1997, 119,6583-6589.
• [18] Okovytyy S., Kholod Y., Qasim M., Fredrickson H., Leszynski l, The Mechanism of Unimolecular Decomposition of2,4,6,8, l O, 12-Hexanitro-2,4,6,8, l O, 12-hexaazaiso-wurtzitane. A Computational DFT Study, J Phys. Chem. A, 2005, 109,2964-2970.
• [19] Zhao X., Hintsa E. l Lee Y. T, Infrared Multiphoton Dissociation ofRDX (hexahydro-1,3,5-trinitro-l,3,5-triazine) in a Molecular Beam,J Chem. Phys., 1988, 88,801-810.
• [20] Bock H., Dammel R., Gas Phase Reactions. Part 66. Essay on Molecular Properties and Models. Part 15. Pyrolysis of Azides in the Gas Phase, Angew. Chem., 1987, 99,518-540.
• [21] van Wullen C., Molecular Density Functional Calculations in the Regular Relativistic Approximation: Method, Application to Coinage Metal Diatomics, Hydrides, Fluorides and Chlorides, and Comparison with first-order Relativistic Calculations, J Chem. Phys., 1998,109(2),392-399.
• [22] Frisch M. l, Trucks G. w., Schlegel H. B., Scuseria G. E., Robb M. A, Cheeseman l R, Zakrzewski V G., l A M. Jr., Stratrnann R E., Burant l C., Dapprich S., Millam l M., Daniels A D.,Kudin M. C. S.K. N.,FarkasO., Tomasil,Barone V,Cossi M.,Cammi R, Mennucci B.,Pomelli C.,Adamo C., ClifIord S., Ochterski l, Petersson G.A,Ayala P. Y.,Cui Q., Morokuma K, Malick D. K, RabuckA D., Raghavachari K, Foresman J. B., Cioslowski l, Ortiz l V, BaboulA G., Stefanov B. B., Liu G., Liashenko A, Piskorz P., KomaromiI., Gomperts R,Martin R L.,Fox D. l, Keith T,Al-Laham M.A, Peng C. Y., Nanayakkara A, Gonzalez C., ChalIacombe M., GilI W. P. M., Johnson B., Chen W., Wong M. w., Andres l L., Gonzalez c., Head-Gordon M., Replogle E. S., Popie l A, Gaussian98, Revision A8, Pittsburgh PA 1998.
• [23] Zhang S., Nguyen H. N., Truong T. N., Theoretical Study of Mechanisms, Thermodynamics, and Kinetics ofthe Decomposition ofGas-Phase a-HMX (Octa-hydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine),J Phys. Chem. A, 2003, 107,2981-2989.
• [24 Shaw R., Walker F. E., Estimated Kinetics and Thermochemistry of Some Initial Unirnolecular Reactions in the Thermal Decomposition ofl ,3,5,7 -tetranitro-l ,3,5,7-tetraazacyclooctane in the Gas Phase, J Phys. Chem., 1977, 81,2572-2576.
• [25] Wu C. l, Fried L. E., Ab Initio Study ofRDX Decomposition Mechanisms, J Phys. Chem., 1997, 101,8675-8679.
• [26] Oxley J. c., Kooh A. B., Szekeres R., Zheng w., Mechanisms of Nitramine Thermolysis, J Phys. Chem., 1994, 98, 7004-7008.