Pursuing reliable thermal analysis techniques for energetic materials: decomposition kinetics and thermal stability of dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50)
- 10 November 2016
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Physical Chemistry Chemical Physics
- Vol. 19 (1), 436-449
- https://doi.org/10.1039/c6cp06498a
Abstract
Thermal decomposition of a novel promising high-performance explosive dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) was studied using a number of thermal analysis techniques (thermogravimetry, differential scanning calorimetry, and accelerating rate calorimetry, ARC). To obtain more comprehensive insight into the kinetics and mechanism of TKX-50 decomposition, a variety of complementary thermoanalytical experiments were performed under various conditions. Non-isothermal and isothermal kinetics were obtained at both atmospheric and low (up to 0.3 Torr) pressures. The gas products of thermolysis were detected in situ using IR spectroscopy, and the structure of solid-state decomposition products was determined by X-ray diffraction and scanning electron microscopy. Diammonium 5,5′-bistetrazole-1,1′-diolate (ABTOX) was directly identified to be the most important intermediate of the decomposition process. The important role of bistetrazole diol (BTO) in the mechanism of TKX-50 decomposition was also rationalized by thermolysis experiments with mixtures of TKX-50 and BTO. Several widely used thermoanalytical data processing techniques (Kissinger, isoconversional, formal kinetic approaches, etc.) were independently benchmarked against the ARC data, which are more germane to the real storage and application conditions of energetic materials. Our study revealed that none of the Arrhenius parameters reported before can properly describe the complex two-stage decomposition process of TKX-50. In contrast, we showed the superior performance of the isoconversional methods combined with isothermal measurements, which yielded the most reliable kinetic parameters of TKX-50 thermolysis. In contrast with the existing reports, the thermal stability of TKX-50 was determined in the ARC experiments to be lower than that of hexogen, but close to that of hexanitrohexaazaisowurtzitane (CL-20).Keywords
Funding Information
- Russian Foundation for Basic Research (16-33-60162 mol_a_dk)
- Russian Science Foundation (14-50-00126, 16-13-10155)
This publication has 56 references indexed in Scilit:
- Thermal decomposition of hydroxylamine: Isoperibolic calorimetric measurements at different conditionsJournal of Hazardous Materials, 2013
- ICTAC Kinetics Committee recommendations for performing kinetic computations on thermal analysis dataThermochimica Acta, 2011
- C2N14: An Energetic and Highly Sensitive Binary AzidotetrazoleAngewandte Chemie, 2011
- Kinetic Analysis of Complex Solid-State Reactions. A New Deconvolution ProcedureThe Journal of Physical Chemistry B, 2011
- Theoretical Study of the 5-Aminotetrazole Thermal DecompositionThe Journal of Physical Chemistry A, 2009
- Azidoformamidinium and Guanidinium 5,5‘-Azotetrazolate SaltsChemistry of Materials, 2005
- Thermal decomposition of aminotetrazolesThermochimica Acta, 2002
- Thermal decomposition of aminotetrazoles: Part 1. 5-AminotetrazoleThermochimica Acta, 1992
- An approach to the solution of the inverse kinetic problem in the case of complex processes. Part III. Parallel independent reactionsThermochimica Acta, 1992
- Thermal decomposition of tetrazole Part III. Analysis of decomposition productsThermochimica Acta, 1990