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Energetic Materials (energetic + material)
Selected AbstractsHigh-Density Energetic Material Hosted in Pure Silica MFI-Type Zeolite Nanocrystals,ADVANCED MATERIALS, Issue 18 2006G. Majano Desensitization of the "green" high-density energetic material Fox-7 inside the pores of pure silica MFI-type nanozeolites (see figure) leads to nonexplosive decomposition about 100,°C above the explosive temperature for the pure substance. [source] Development and Testing of Energetic Materials: The Concept of High Densities Based on the Trinitroethyl FunctionalityADVANCED FUNCTIONAL MATERIALS, Issue 3 2009Michael Göbel Abstract The development of new energetic materials is an emerging area of materials chemistry facilitated by a worldwide need to replace materials used at present, due to environmental considerations and safety requirements, while at the same time securing high performance. The development of such materials is complex, owing to the fact that several different and apparently mutually exclusive material properties have to be met in order for a new material to become widely accepted. In turn, understanding the basic principles of structure property relationships is highly desirable, as such an understanding would allow for a more rational design process to yield the desired properties. This article covers the trinitroethyl functionality and its potential for the design of next generation energetic materials, and describes relevant aspects of energetic materials chemistry including theoretical calculations capable of reliably predicting material properties. The synthesis, characterization, energetic properties, and structure property relationships of several new promising compounds displaying excellent material properties are reported with respect to different kinds of applications and compared to standard explosives currently used. Based on a review of trinitroethyl-containing compounds available in the literature, as well as this new contribution, it is observed that high density can generally be obtained in a more targeted manner in energetic materials taking advantage of noncovalent bonding interactions, a prerequisite for the design of next generation energetic materials. [source] Acid-Base Interactions in Energetic Materials: I. The Hard and Soft Acids and Bases (HSAB) Principle,Insights to Reactivity and Sensitivity of Energetic MaterialsPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 1 2005Ernst-Christian Koch Abstract The chemistry of energetic materials can be described applying acid-base reaction formalism. Addressing the HSAB concept, the number of electrons transferred, ,N, in an acid-base reaction, allows for description and prediction of properties of composite and homogeneous materials. At first ,N helps in estimating the rate of reaction of binary systems with either given fuel or oxidizer. Nevertheless ,N is only a relative number thus the range of comparability remains narrow. At second ,N can be used as a measure for the sensitivity of homogeneous explosives. The increased reactivity of hypothetical fragments to recombine in a reaction such as R3C.+.NO2=R3C,NO2 given by ,N correlates very well with experimentally determined reduced impact sensitivity of 1,3,5-trinitrobenzene compounds. On the contrary the rising impact sensitivity of metal azides correlates with rising values of ,N of Mn+/N3, reaction because increased reactivity, that is increased electron transfer from the azide anion to the metal cation triggers formation of the azide radical (.N3). The latter then decomposes rapidly to give dinitrogen. This increased reactivity/sensitivity of metral azides coincides with covalent bonding whereas ionic azides are relatively insensitive. [source] Molecular Modeling in Crystal Engineering for Processing of Energetic MaterialsPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 6 2003Stéphane Bénazet Abstract Nowadays molecular modeling is available to explain molecular phenomena. This approach helps to compute crystal surface property effects that can be used both for morphology studies and optimal design of "bonding agents" to prevent filler-binder detachment. The principles of crystal growth and of interaction energy computing have been applied to Hexanitrohexaazaisowurtzitane (HNIW). Crystallization experiments validate our calculations. Three families of additives of crystal growth are distinguished: the retarding (and inhibitor) agents, the promoters and finally the "tailor-mades". Retarding and inhibitor agents are the most interesting one to find bonding agents. HNIW is used to present our methodology, but engineering using molecular modeling could be generalized to other fillers. [source] Thermal Decomposition of Energetic Materials 84: Pyrolysis of 5-Substituted 1,3,5-TrinitrohexahydropyrimidinesPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 2 2003Brian Abstract Results of slow and fast pyrolysis were compared for 1,3,5-trinitrohexahydropyrimidine compounds in which the 5-position was substituted by H, CH3, NO2, CH2ONO2, and CH2N3. IR and Raman spectroscopy were used to identify and quantify all of the gaseous products. The decomposition process appears to be initiated by reactions at the 5-position of the ring. The gases produced are rather similar for all of the compounds, however the different functional groups impart their own signature on the concentrations of several products. [source] Thermal Decomposition of Energetic Materials 85: Cryogels of Nanoscale Hydrazinium Diperchlorate in Resorcinol-FormaldehydePROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 2 2003Bryce Abstract The objective of this work was to try to desensitize an energetic material by using sol-gel processing and freeze drying to incorporate the energetic material into the fuel matrix on the nano (or at least submicron) particle size scale. Hydrazinium diperchlorate ([N2H6][ClO4]2 or HP2) and resorcinol-formaldehyde (RF) were chosen as the oxidizer and fuel, respectively. Solid loading up to 88% HP2 was achieved by using the sol gel-to-cryogel method. Various weight percentages of HP2 in RF were characterized by elemental analysis, scanning electron (SEM) and optical microscopy, T-jump/FTIR spectroscopy, DSC, and drop-weight impact. SEM indicated that 20,50,nm diameter HP2 plates aggregated into porous 400,800,nm size clusters. Below 80% HP2 the cryogels are less sensitive to impact than physical mixtures having the same ratios of HP2 and RF. The decomposition temperatures of the cryogels are higher than that of pure HP2, which is consistent with their lower impact sensitivity. The heat of decomposition as measured at a low heating rate increases with increasing percentage of HP2. The cryogels and physical mixtures release similar amounts of energy, but the cryogels exhibit mainly a single exotherm by DSC whereas the physical mixtures showed a two-step energy release. Flash pyrolysis revealed gaseous product ratios suggestive of more energy being released from the cryogels than the physical mixtures. Cryogels also burn faster by visual observation. [source] Weathering and aging of 2,4,6-trinitrotoluene in soil increases toxicity to potworm Enchytraeus crypticusENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2005Roman G. Kuperman Abstract Energetic materials are employed in a wide range of commercial and military activities and often are released into the environment. Scientifically based ecological soil-screening levels (Eco-SSLs) are needed to identify contaminant explosive levels in soil that present an acceptable ecological risk. Insufficient information for 2,4,6-trinitrotoluene (TNT) to generate Eco-SSLs for soil invertebrates necessitated toxicity testing. We adapted the standardized Enchytraeid Reproduction Test and selected Enchytraeus crypticus for these studies. Tests were conducted in Sassafras sandy loam soil, which supports relatively high bioavailability of TNT. Weathering and aging procedures for TNT amended to test soil were incorporated into the study design to produce toxicity data that better reflect the soil exposure conditions in the field compared with toxicity in freshly amended soils. This included exposing hydrated TNT-amended soils in open glass containers in the greenhouse to alternating wetting and drying cycles. Definitive tests showed that toxicity for E. crypticus adult survival and juvenile production was increased significantly in weathered and aged soil treatments compared with toxicity in freshly amended soil based on 95% confidence intervals. The median effect concentration and 20% effective concentration for reproduction were 98 and 77 mg/kg, respectively, for TNT freshly amended into soil and 48 and 37 mg/kg, respectively, for weathered and aged TNT soil treatments. These findings of increased toxicity to E. crypticus in weathered and aged TNT soil treatments compared with exposures in freshly amended soils show that future investigations should include a weathering and aging component to generate toxicity data that provide more complete information on ecotoxicological effects of energetic contaminants in soil. [source] Energetic materials: variable-temperature crystal structure of ,-NTOJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2003Nadezhda B. Bolotina The crystal structure of the metastable , form of 5-nitro-2,4-dihydro-3H -1,2,4-triazol-3-one (,-NTO, monoclinic, P21/c) has been investigated at five temperatures in the range 100,298,K using single-crystal X-ray diffraction techniques. The second-rank thermal expansion tensor has been determined to describe thermal behavior of the crystal. The most significant thermal expansion is in a plane, which is almost perpendicular to the planes of all the NTO molecules. Perpendicular to the plane of maximal thermal expansion, a modest thermal contraction takes place. Both thermal expansion and contraction of the crystal lattice indicate anharmonicity of the atomic thermal motion. The experimental thermal variation of the unit-cell parameters is in qualitative agreement with that previously obtained from molecular dynamics calculations. Rigid-body analysis of the molecular thermal motion was performed using the libration and translation second-rank tensors. Although the translation part of the thermal motion is not strongly anisotropic, the largest displacements of the NTO molecules are oriented in the plane of maximal thermal expansion of the crystal and have significant anharmonic components. The libration motion is more anisotropic, and the largest libration as well as the largest translation principal axes are directed along the C5,N5 bond in each NTO molecule. [source] New precursors for hexanitrohexaazaisowurtzitane (HNIW, CL-20)JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2000Kyoo-Hyun Chung Two new polyacylhexaazaisowurtzitanes were synthesized. Pentaacetyl- or pentaacetylformylhexaazaisowurtzitane can be a precursor in the preparation of HNIW, recently developed highly energetic material. [source] Synthesis and Characterization of 1-Azido-2-Nitro-2-Azapropane and 1-Nitrotetrazolato-2-Nitro-2-AzapropanePROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 4 2006Roland Boese Abstract 1-Azido-2-nitro-2-azapropane (1) was synthesized in high yield from 1-chloro-2-nitro-2-azapropane and sodium azide. 1-Nitrotetrazolato-2-nitro-2-azapropane (2) was synthesized in high yield from 1-chloro-2-nitro-2-azapropane and silver nitrotetrazolate. The highly energetic new compounds (1 and 2) were characterized using vibrational (IR and Raman) and multinuclear NMR spectroscopy (1H, 13C, 14N), elemental analysis and low-temperature single crystal X-ray diffraction. 1-Azido-2-nitro-2-azapropane (1) represents a covalently bound liquid energetic material which contains both a nitramine unit and an azide group in the molecule. 1-Nitrotetrazolato-2-nitro-2-azapropane (2) is a covalently bound room-temperature stable solid which contains a nitramine group and a nitrotetrazolate ring unit in the molecule. Compounds 1 and 2 are hydrolytically stable at ambient conditions. The impact sensitivity of compound 1 is very high (<1,J) whereas compound 2 is less sensitive (<6,J). [source] Synthesis, Characterization and Thermal Behaviour of Guanidinium-5-aminotetrazolate (GA) , A New Nitrogen-Rich CompoundPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 4 2003Jochen Neutz Abstract This work describes the synthesis and the thermoanalytical characterization of guanidinium-5-aminotetrazolate (GA). GA is a new nitrogen-rich energetic material. It is not mentioned in the chemical literature so far. The molecular structure of the compound has been determined by IR, 1H-, 13C- and 15N-NMR spectroscopy. The thermal properties, the decomposition pathways and its volatile products were investigated by thermal analysis and are discussed. [source] Thermal Decomposition of Energetic Materials 85: Cryogels of Nanoscale Hydrazinium Diperchlorate in Resorcinol-FormaldehydePROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 2 2003Bryce Abstract The objective of this work was to try to desensitize an energetic material by using sol-gel processing and freeze drying to incorporate the energetic material into the fuel matrix on the nano (or at least submicron) particle size scale. Hydrazinium diperchlorate ([N2H6][ClO4]2 or HP2) and resorcinol-formaldehyde (RF) were chosen as the oxidizer and fuel, respectively. Solid loading up to 88% HP2 was achieved by using the sol gel-to-cryogel method. Various weight percentages of HP2 in RF were characterized by elemental analysis, scanning electron (SEM) and optical microscopy, T-jump/FTIR spectroscopy, DSC, and drop-weight impact. SEM indicated that 20,50,nm diameter HP2 plates aggregated into porous 400,800,nm size clusters. Below 80% HP2 the cryogels are less sensitive to impact than physical mixtures having the same ratios of HP2 and RF. The decomposition temperatures of the cryogels are higher than that of pure HP2, which is consistent with their lower impact sensitivity. The heat of decomposition as measured at a low heating rate increases with increasing percentage of HP2. The cryogels and physical mixtures release similar amounts of energy, but the cryogels exhibit mainly a single exotherm by DSC whereas the physical mixtures showed a two-step energy release. Flash pyrolysis revealed gaseous product ratios suggestive of more energy being released from the cryogels than the physical mixtures. Cryogels also burn faster by visual observation. [source] Evidence for the Hypothesis of Ignition of Propellants by Metallic Vapour DepositionPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 6 2002Michael This paper examines the experimental evidence to support the hypothesis of ignition of energetic material by the process of metallic vapour deposition. The hypothesis has been presented previously, and this is the continuation of the work. The hypothesis has been developed at QinetiQ to explain certain measurements of incident radiative flux during electrothermal-chemical (ETC) experimentation, which show no correlation with the ignition event. Indeed, measured levels of radiation have been so low that radiative energy transfer for ETC plasma ignition could be said to be negligible. Measurement of the thickness of a metal layer resulting from dropwise vapour condensation gives good correlation to the flux requirements for ignition. [source] Development and Testing of Energetic Materials: The Concept of High Densities Based on the Trinitroethyl FunctionalityADVANCED FUNCTIONAL MATERIALS, Issue 3 2009Michael Göbel Abstract The development of new energetic materials is an emerging area of materials chemistry facilitated by a worldwide need to replace materials used at present, due to environmental considerations and safety requirements, while at the same time securing high performance. The development of such materials is complex, owing to the fact that several different and apparently mutually exclusive material properties have to be met in order for a new material to become widely accepted. In turn, understanding the basic principles of structure property relationships is highly desirable, as such an understanding would allow for a more rational design process to yield the desired properties. This article covers the trinitroethyl functionality and its potential for the design of next generation energetic materials, and describes relevant aspects of energetic materials chemistry including theoretical calculations capable of reliably predicting material properties. The synthesis, characterization, energetic properties, and structure property relationships of several new promising compounds displaying excellent material properties are reported with respect to different kinds of applications and compared to standard explosives currently used. Based on a review of trinitroethyl-containing compounds available in the literature, as well as this new contribution, it is observed that high density can generally be obtained in a more targeted manner in energetic materials taking advantage of noncovalent bonding interactions, a prerequisite for the design of next generation energetic materials. [source] The electronically excited states of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine): Vertical excitationsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 11 2009Itamar Borges Jr Abstract The RDX molecule, hexahydro-1,3,5-trinitro-1,3,5-triazine, is a key component for several energetic materials, which have important practical applications as explosives. A systematic study of the electronic excited states of RDX in gas phase using time-dependent density functional theory (TDDFT), algebraic diagrammatic construction through second order method [ADC (2)], and resolution of the identity coupled-cluster singles and doubles method (RI-CC2) was carried out. Transition energies and optical oscillator strengths were computed for a maximum of 40 transitions. RI-CC2 and ADC (2) predict a spectrum shaped by three intense ,-,* transitions, two with charge transfer and one with localized character. TDDFT fails in the description of the charge transfer states. The low-energy band of the experimental UV spectrum of RDX is assigned to the first charge transfer state. Two alternative assignments of the high-energy band are proposed. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [source] Organic cyclic difluoramino-nitramines: infrared and Raman spectroscopy of 3,3,7,7-tetrakis(difluoramino)octahydro 1,5-dinitro-1,5-diazocine (HNFX)JOURNAL OF RAMAN SPECTROSCOPY, Issue 8 2009Philippe F. Weck Abstract We present the first vibrational structure investigation of 3,3,7,7-tetrakis(difluoramino)octahydro-1,5-dinitro- 1,5-diazocine (HNFX),and, more generally, of a member of the new class of gem -bis(difluoramino)-substituted heterocyclic nitramine energetic materials,using combined theoretical and experimental approaches. Optimized molecular structure and vibrational spectra of the Ci, symmetry conformer constituting the HNFX crystal were computed using density functional theory methods. Fourier transform infrared and Raman spectra of HNFX crystalline samples were also collected at ambient temperature and pressure. The average deviation of calculated structural parameters from X-ray diffraction data is ,1% at the B3LYP/6-311 + + G(d,p) level of theory, suggesting the absence of significant molecular distortion induced by the crystal field. Very good agreement was found between simulated and measured spectra, allowing reliable assignment of the fundamental normal modes of vibration of the HNFX crystal. Detailed analysis of the normal modes of the C,(NF2)2 and N,NO2 moieties was performed due to their critical importance in the initial steps of the molecular homolytic fragmentation process. Copyright © 2009 John Wiley & Sons, Ltd. [source] Method for estimating decomposition characteristics of energetic chemicalsPROCESS SAFETY PROGRESS, Issue 4 2003Sima Chervin Experimental data on the decomposition characteristics of approximately400 chemicals, representing various classes of energetic materials, were summarized by chemical class and statistically analyzed. Average decomposition characteristics, such as energy of decomposition and decomposition onset temperature, were determined for chemical classes containing the following energetic groups: nitro, nitroso, N-oxide, oxime, hydroxylamine, tetrazole, azide, triazene, triazole, diazo, azo, hydrazine, and perchlorate. Additional statistical information is presented for each chemical class, such as number of chemicals analyzed, ranges, and standard deviations for the decomposition parameters analyzed. For chemical classes containing an energetic group attached to an aromatic ring, the presence and position of another substituting group in the ring can significantly influence the decomposition onset temperature. The study summarizes the list of activating and deactivating functional groups, and the positions in the ring where the strongest activation or deactivation occurs. The authors also recommend a method for estimating decomposition parameters of new chemicals. [source] Results from Research Collaboration , A Review over 20 YearsPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 3 2009Abstract Over the last twenty years, the level of international research collaboration on military energetic materials has increased significantly and has been reported in the literature. It is time to look at what has been done and to critically examine that benefits that it has produced. The range of programmes has covered the whole range of energetic materials and in addition to the study of new materials and new forms of materials, it has covered modelling as well as standards and protocols. Programmes have ranged from pressed explosives to rocket propellants and from IM technology to environmental and life management. It can be argued that these programmes have provided the participating nations with materials as well as the understanding to better manage their behaviour and use. Without this range of activity, significantly less would have been achieved. This will be discussed in the light of a selection of published papers and reports. [source] The Effect of Cook-Off on the Bulk Permeability of a Plastic Bonded ExplosivePROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 5 2006Guillermo Terrones Abstract Plastic bonded explosives when exposed to prolonged heating environments undergo a variety of changes that affect their bulk chemical, thermophysical, and mechanical properties. During slow heating conditions, referred to as cook-off, the thermal behavior of the polymeric binder plays an important role in the transformations of these composite energetic materials. The recently introduced Darcian flow hypothesis for PBX-9501 implies that, during preignition, temperature gradients will lead to pressure gradients which in turn will drive convection of decomposition gases throughout the explosive, thus affecting ignition time and location. Here, we focus on the cook-off behavior of PBX-9501 and investigate its effects on bulk permeability to gases produced as a result of thermal decomposition. The concept of Darcian convection through porous media is defined and illustrated in detail by the derivation of the governing equations for a permeameter. Based on a systematic analysis involving: 1) our current understanding about binder behavior as a function of temperature, 2) the physics of the gas permeameter apparatus, 3) the concept of liquid drainage by gas, and 4) the experimental record of four permeameter experiments with cooked PBX-9501, we conclude that samples heated up to 186,°C were not permeable in the Darcy-flow sense. [source] Acid-Base Interactions in Energetic Materials: I. The Hard and Soft Acids and Bases (HSAB) Principle,Insights to Reactivity and Sensitivity of Energetic MaterialsPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 1 2005Ernst-Christian Koch Abstract The chemistry of energetic materials can be described applying acid-base reaction formalism. Addressing the HSAB concept, the number of electrons transferred, ,N, in an acid-base reaction, allows for description and prediction of properties of composite and homogeneous materials. At first ,N helps in estimating the rate of reaction of binary systems with either given fuel or oxidizer. Nevertheless ,N is only a relative number thus the range of comparability remains narrow. At second ,N can be used as a measure for the sensitivity of homogeneous explosives. The increased reactivity of hypothetical fragments to recombine in a reaction such as R3C.+.NO2=R3C,NO2 given by ,N correlates very well with experimentally determined reduced impact sensitivity of 1,3,5-trinitrobenzene compounds. On the contrary the rising impact sensitivity of metal azides correlates with rising values of ,N of Mn+/N3, reaction because increased reactivity, that is increased electron transfer from the azide anion to the metal cation triggers formation of the azide radical (.N3). The latter then decomposes rapidly to give dinitrogen. This increased reactivity/sensitivity of metral azides coincides with covalent bonding whereas ionic azides are relatively insensitive. [source] New Aspects of Impact Reactivity of Polynitro Compounds, Part III.PROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 6 2003Impact Sensitivity as a Function of the Imtermolecular Interactions Abstract Published data of impact sensitivity of 33 polynitro compounds detected by sound were expressed as the drop energy, Edr, required for 50 percent initiation probability. A logarithmic relationship has been found between the Edr values and heats of fusion of the said compounds. The relationship has been found to be in accordance with the idea concerning the role of plastic deformations of crystal played in the initiation of energetic materials by impact and shock. An analogous application of heats of sublimation has not given convincing results. [source] Charge-density studies of energetic materials: CL-20 and FOX-7.ACTA CRYSTALLOGRAPHICA SECTION B, Issue 4 2008Corrigendum A corrigendum to the paper by Meents et al. (2008), Acta Cryst. B64, 4249 to correct the nomenclature for CL-20. [source] Energetic N,N,N,,N, -Tetraaminopiperazinium SaltsCHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 3 2008Haixiang Gao Prof. Abstract The formation of tetraaminopiperazinium salts using water as solvent provides a green, straightforward approach to highly energetic salts that exhibit good thermal stabilities and moderate densities. The N,N,N,,N, -tetraaminopiperazinium cation was selected for this study because of its high nitrogen,nitrogen bond content and its high positive heat of formation. Theoretical and empirical calculations on energetic salts based on this nitrogen-rich cation reveal them to have high positive molar enthalpies of formation, as high as 1034.0,kJ,mol,1, supporting the application of these new salts as potential energetic materials. [source] Thermal Behavior and Non-isothermal Decomposition Reaction Kinetics of NEPE Propellant with Ammonium DinitramideCHINESE JOURNAL OF CHEMISTRY, Issue 5 2010Weiqiang Pang Abstract Thermal decomposition behavior and non-isothermal decomposition reaction kinetics of nitrate ester plasticized polyether NEPE propellant containing ammonium dinitramide (ADN), which is one of the most important high energetic materials, were investigated by DSC, TG and DTG at 0.1 MPa. The results show that there are four exothermic peaks on DTG curves and four mass loss stages on TG curves at a heating rate of 2.5 K·min,1 under 0.1 MPa, and nitric ester evaporates and decomposes in the first stage, ADN decomposes in the second stage, nitrocellulose and cyclotrimethylenetrinitramine (RDX) decompose in the third stage, and ammonium perchlorate decomposes in the fourth stage. It was also found that the thermal decomposition processes of the NEPE propellant with ADN mainly have two mass loss stages with an increase in the heating rate, that is the result of the decomposition heats of the first two processes overlap each other and the mass content of ammonium perchlorate is very little which is not displayed in the fourth stage at the heating rate of 5, 10, and 20 K·min,1 probably. It was to be found that the exothermal peak temperatures increased with an increase in the heating rate. The reaction mechanism was random nucleation and then growth, and the process can be classified as chemical reaction. The kinetic equations of the main exothermal decomposition reaction can be expressed as: d,/dt=1012.77(3/2)(1,,)[,ln(1,,)]1/3 e,1.723×104/T. The critical temperatures of the thermal explosion (Tbe and Tbp) obtained from the onset temperature (Te) and the peak temperature (Tp) on the condition of ,,0 are 461.41 and 458.02 K, respectively. Activation entropy (,S,), activation enthalpy (,H,), and Gibbs free energy (,G,) of the decomposition reaction are ,7.02 J·mol,1·K,1, 126.19 kJ·mol,1, and 129.31 kJ·mol,1, respectively. [source] | ||||||||||||||||||||||||||||