scholarly journals Thermal Decomposition Kinetics and Compatibility of 3,5-difluoro-2,4,6-trinitroanisole (DFTNAN)

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4186
Author(s):  
Fei Hu ◽  
Lin-Jian Wang ◽  
Wei Zhao ◽  
Yu-Cun Liu ◽  
Su-Ming Jing ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Decomposition Temperature ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
High Explosives ◽  
Kinetic And Thermodynamic Parameters ◽  
Study Results ◽  
Mass Ratios ◽  
Decomposition Behavior ◽  
Stanag 4147

In this paper, the thermal decomposition behavior of 3,5-difluoro-2,4,6-trinitroanisole (DFTNAN) was studied by differential scanning calorimetry (DSC) and thermogravimetry (TG) by using different heating rates (2, 5, 10, 15 °C·min−1). Subsequently, the kinetic and thermodynamic parameters of non-isothermal thermal decomposition of DFTNAN were calculated. The critical temperature of thermal explosion (Tb) and self-accelerating decomposition temperature (TASDT) were determined to be 249.03 °C and 226.33 °C, respectively. The compatibility of DFTNAN with a number of high explosives (cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX), 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaaza-tetracyclo-[5.5.0.05,9.03,11]-dodecane (CL-20) and dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate (TKX-50)) was studied at different mass ratios using DSC. The criteria to judge the compatibility between the materials were based on a standardization agreement (STANAG 4147). The thermodynamic study results revealed that DFTNAN possessed superior thermal safety and stability. The experimental of compatibility results indicated that the mass ratios of the high explosives in the DFTNAN/RDX, DFTNAN/HMX and DFTNAN/CL-20 compositions more than 40%, 60% and 70% exhibited good compatibility, whereas DFTNAN/TKX-50 demonstrated poor compatibility.

scholarly journals Hydrothermal Synthesis of Hematite Nanoparticles Decorated on Carbon Mesospheres and Their Synergetic Action on the Thermal Decomposition of Nitrocellulose

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 968 ◽  
Author(s):  
Abdenacer Benhammada ◽  
Djalal Trache ◽  
Mohamed Kesraoui ◽  
Salim Chelouche
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Analytical Techniques ◽  
Decomposition Reaction ◽  
Decomposition Temperature ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Nano Catalyst ◽  
Average Size ◽  
A Minor

In this study, carbon mesospheres (CMS) and iron oxide nanoparticles decorated on carbon mesospheres (Fe2O3-CMS) were effectively synthesized by a direct and simple hydrothermal approach. α-Fe2O3 nanoparticles have been successfully dispersed in situ on a CMS surface. The nanoparticles obtained have been characterized by employing different analytical techniques encompassing Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The produced carbon mesospheres, mostly spherical in shape, exhibited an average size of 334.5 nm, whereas that of Fe2O3 supported on CMS is at around 80 nm. The catalytic effect of the nanocatalyst on the thermal behavior of cellulose nitrate (NC) was investigated by utilizing differential scanning calorimetry (DSC). The determination of kinetic parameters has been carried out using four isoconversional kinetic methods based on DSC data obtained at various heating rates. It is demonstrated that Fe2O3-CMS have a minor influence on the decomposition temperature of NC, while a noticeable diminution of the activation energy is acquired. In contrast, pure CMS have a slight stabilizing effect with an increase of apparent activation energy. Furthermore, the decomposition reaction mechanism of NC is affected by the introduction of the nano-catalyst. Lastly, we can infer that Fe2O3-CMS may be securely employed as an effective catalyst for the thermal decomposition of NC.

Bis (2,2-Dinitroethyl-N-Nitro)Ethylenediamine-Based Energetic Salts and their Thermolysis Studies

2013 ◽  
Vol 781-784 ◽  
pp. 2458-2462
Author(s):  
Jin Hong Song ◽  
Zhi Ming Zhou ◽  
Shu Bo Wang
Keyword(s):  
Thermal Decomposition ◽  
High Yield ◽  
Detonation Properties ◽  
Activation Entropy ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Exponential Factor ◽  
Energetic Salts ◽  
Decomposition Behavior ◽  
Impact Sensitivities

New energetic bis (2,2-dinitroethyl-N-nitro) ethylenediamine-based salts exhibiting reasonable physical properties, good detonation properties and relatively low impact sensitivities were synthesized in high yield by direct neutralization reactions. The thermal decomposition behavior of two new bis (2,2-dinitroethyl-N-nitro) ethylenediamine-based energetic salts was firstly measured using differential scanning calorimetry (DSC) at six different heating rates. The thermal decomposition kinetics and several thermodynamic parameters of the salts, such as apparent activation energy (E), pre-exponential factor (A), extrapolated onset temperature (T0), activation entropy (∆S≠), activation enthalpy (∆H≠), activation Gibbs free energy (∆G≠), critical temperature of thermal explosion (Tb) and the Arrhenius equations were obtained under non-isothermal conditions by DSC.

scholarly journals Study on the Performances of PLLA/CaSiO3 Composites

2021 ◽  
Vol 236 ◽  
pp. 02037
Author(s):  
Qiuhe Zhang ◽  
Lisha Zhao ◽  
Ting Deng ◽  
Yanhua Cai
Keyword(s):  
Thermal Decomposition ◽  
Crystallization Temperature ◽  
Melting Process ◽  
Melting Behavior ◽  
Decomposition Temperature ◽  
Melt Crystallization ◽  
Heating Rates ◽  
Promoting Effect ◽  
Decomposition Behavior ◽  
Relationship Of

In the current work, calcium silicate (CaSiO3) was blended with the poly (L-lactic acid) (PLLA) to prepare the PLLA/CaSiO3 composites, and the crystallization process, melting process and thermal decomposition behavior of PLLA/CaSiO3 composites were studied. The promoting effect of CaSiO3 on the crystallization of PLLA was proved by the melt-crystallization, and the CaSiO3 content was a crucial factor to the crystallization behavior of PLLA. The crystallization temperature significantly affected the melting behavior of PLLA, and the double melting peaks degenerated into the single melting peak with the increasing of crystallization temperature from 90 °C to 130 °C. Additionally, for a given PLLA/CaSiO3 sample, the different melting processes in heating after the melt-crystallization results from the different heating rates, and the appearance of the cold-crystallization peak indicated the medium nucleation capacity of CaSiO3. The presence of CaSiO3 decreased the onset thermal decomposition temperature of PLLA, and this effect depended on the competitive relationship of the poor compatibility of PLLA with CaSiO3 and the content of CaSiO3 with high thermal stability.

Non-Isothermal Decomposition Kinetic of Polypropylene/Hydrotalcite Composite

2019 ◽  
Vol 19 (11) ◽  
pp. 7493-7501 ◽  
Author(s):  
Sheng Xu ◽  
Min Zhang ◽  
Siyu Li ◽  
Moyu Yi ◽  
Shigen Shen ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Thermal Decomposition ◽  
Nitrogen Atmosphere ◽  
Heating Rates ◽  
Decomposition Reactions ◽  
Kinetic And Thermodynamic Parameters ◽  
Málek Method ◽  
Boundary Reaction ◽  
Phase Boundary Reaction ◽  
Thermal Stability Of

P3O5-10 pillared Mg/Al hydrotalcite (HTs) as a functional fire-retarding filler was successfully prepared by impregnation-reconstruction, where the HTs was used to prepare polypropylene (PP) and HTs composite (PP/HTs). Thermal decomposition was crucial for correctly identifying the thermal behavior for the PP/HTs, and studied using thermogravimetry (TG) at different heating rates. Based on single TG curves and Málek method, as well as 41 mechanism functions, the thermal decompositions of the PP/HTs composite and PP in nitrogen atmosphere were studied under non-isothermal conditions. The mechanism functions of the thermal decomposition reactions for the PP/HTs composite and PP were separately “chemical reaction F3” and “phase boundary reaction R2,” which were also in good agreement with corresponding experimental data. It was found that the addition of the HTs increased the apparent activation energy Ea of the PP/HTs comparing to the PP, which improved the thermal stability of the polypropylene. A difference in the set of kinetic and thermodynamic parameters was also observed between the PP/HTs and PP, particularly with respect to lower ΔS≠ value assigned to higher thermal stability of the PP/HTs composite.

scholarly journals Preparation of Few-Layered WS2 and Its Thermal Catalysis for Dihydroxylammonium-5,5′-Bistetrazole-1,1′-Diolate

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Yiping Shang ◽  
Wu Yang ◽  
Yabei Xu ◽  
Siru Pan ◽  
Huayu Wang ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Thermal Decomposition ◽  
Analysis Data ◽  
Decomposition Temperature ◽  
Thermal Excitation ◽  
Layered Semiconductor ◽  
Initial Decomposition Temperature ◽  
Thermal Decomposition Behavior ◽  
Decomposition Behavior ◽  
Catalytic Effects

In this study, few-layered tungsten disulfide (WS2) was prepared using a liquid phase exfoliation (LPE) method, and its thermal catalytic effects on an important kind of energetic salts, dihydroxylammonium-5,5′-bistetrazole-1,1′-diolate (TKX-50), were investigated. Few-layered WS2 nanosheets were obtained successfully from LPE process. And the effects of the catalytic activity of the bulk and few-layered WS2 on the thermal decomposition behavior of TKX-50 were studied by using synchronous thermal analysis (STA). Moreover, the thermal analysis data was analyzed furtherly by using the thermokinetic software AKTS. The results showed the WS2 materials had an intrinsic thermal catalysis performance for TKX-50 thermal decomposition. With the few-layered WS2 added, the initial decomposition temperature and activation energy (Ea) of TKX-50 had been decreased more efficiently. A possible thermal catalysis decomposition mechanism was proposed based on WS2. Two dimensional-layered semiconductor WS2 materials under thermal excitation can promote the primary decomposition of TKX-50 by enhancing the H-transfer progress.

Thermal Decomposition and Flame Retardance Behavior of Nanometer Magnesium Oxychloride Crystal Salt Involved in SMC

2009 ◽  
Vol 66 ◽  
pp. 163-166 ◽  
Author(s):  
Jian Li ◽  
Zhi Xiong Huang ◽  
Ying Zhao
Keyword(s):  
Thermal Decomposition ◽  
Flame Retardance ◽  
Scanning Calorimetry ◽  
Structural Water ◽  
Crystal Water ◽  
Molding Compound ◽  
Sheet Molding Compound ◽  
Initial Stage ◽  
Magnesium Oxychloride ◽  
Decomposition Behavior

A detailed study of thermal decomposition behavior of nanometer magnesium oxychloride crystal salt involved in sheet molding compound has been carried out using differential scanning calorimetry, thermogravimetry and X-ray diffraction. The decomposing temperature changed from 112°C at the initial stage to 559°C at the end of the process. The results indicated that the thermal decomposition was carried out in the following three steps: releasing crystal water, then HCl secondly and finally structural water, the residua was magnesia. Nanometer magnesium oxychloride crystal salt addictives was used as flame retardance in sheet molding compound.

Measurement of Thermal Decomposition Temperature and Rate of Sodium Hydride

2020 ◽  
Author(s):  
Munemichi Kawaguchi
Keyword(s):  
Thermal Decomposition ◽  
Mass Loss ◽  
Heating Temperature ◽  
Fission Products ◽  
Sodium Hydride ◽  
Decomposition Temperature ◽  
Cold Trap ◽  
Thermal Decomposition Temperature ◽  
Heating Rates ◽  
Fundamental Research

Abstract In decommissioning sodium-cooled fast reactors, the operators can be exposed to radiation during dismantling of cold trap equipment (C/T). The C/T is higher dose equipment because the C/T trapped tritium of fission products during the operation to purify the sodium coolant. In this study, thermal decomposition temperature and rate of sodium hydride (NaH) were measured as a fundamental research for development of “thermolysis” process prior to the dismantling. We measured the thermal decomposition temperature and rate using NaH powder (95.3%, Sigma-Aldrich) in alumina pan with ThermoGravimetry-Differential Thermal Analysis (TG-DTA) instrument (STA2500 Regulus, NETZSCH Japan). The heating rates of TG-DTA were set to β = 2.0, 5.0, 10.0 and 20.0 K/min. The DTA showed endothermic reaction and the TG showed two-steps mass-loss over 580K. This first-step mass-loss was consistent with change of chemical composition of the NaH with heating (NaH → Na+1/2H2). The thermal decomposition temperature and rate were obtained from the onset temperature of the mass-loss and the simplified Kissinger plots, respectively. Furthermore, we set to the thermal decomposition temperature of around 590K, and the mass-loss rates were measured. As a result, over 590K, the thermal decomposition occurred actively, and showed good agreement with the estimation curves obtained by the simplified Kissinger plots. The thermal decomposition rate strongly depended on the heating temperature.

scholarly journals Thermal Decomposition Behavior of Melaminium Benzoate Dihydrate

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
N. Kanagathara ◽  
M. K. Marchewka ◽  
K. Pawlus ◽  
S. Gunasekaran ◽  
G. Anbalagan
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Effective Activation Energy ◽  
Preexponential Factor ◽  
Effective Activation ◽  
Heating Rates ◽  
Monoclinic System ◽  
Model Free ◽  
Thermal Decomposition Behavior ◽  
Decomposition Behavior

Crystals of melaminium benzoate dihydrate (MBDH) have been grown from aqueous solution by slow solvent evaporation method at room temperature. Powder X-ray diffraction analysis confirms that MBDH crystallizes in the monoclinic system (C2/c). Thermal decomposition behavior of MBDH has been studied by thermogravimetric analysis at three different heating rates: 10, 15, and 20°C/min. Nonisothermal studies of MBDH revealed that the decomposition occurs in three stages. The values of effective activation energy (Ea) and preexponential factor (ln A) of each stage of thermal decomposition for all heating rates were calculated by model free methods: Arrhenius, Flynn-Wall, Friedman, Kissinger, and Kim-Park methods. A significant variation of effective activation energy (Ea) with conversion (α) indicates that the process is kinetically complex. The linear relationship between the A and Ea values was established (compensation effect). Avrami-Erofeev model (A3), contracting cylinder (R2), and Avrami-Erofeev model (A4) were accepted by stages I, II, and III, respectively. DSC has also been performed.

Thermal behavior of modified poly(L-lactic acid): effect of aromatic multiamide derivative based on 1H-benzotriazole

e-Polymers ◽  
2016 ◽  
Vol 16 (4) ◽  
pp. 303-311 ◽  
Author(s):  
Yan-Hua Cai ◽  
Li-Sha Zhao
Keyword(s):  
Thermal Stability ◽  
Thermal Decomposition ◽  
Lactic Acid ◽  
Isothermal Crystallization ◽  
Crystallization Behavior ◽  
Nucleating Agent ◽  
Melting Behavior ◽  
Decomposition Temperature ◽  
Scanning Calorimetry ◽  
Onset Crystallization Temperature

AbstractThe goal of this work was to synthesis a novel aromatic multiamide derivative based on 1H-benzotriazole (PB) as an organic nucleating agent for poly(L-lactic acid) (PLLA), and investigate the effect of PB on the non-isothermal crystallization, melting behavior and thermal decomposition of PLLA. Here, PB was firstly synthesized through 1H-benzotriazole aceto-hydrazide and terephthaloyl chloride, then PB-nucleated PLLA was fabricated via melt-blending technology at various PB concentration from 0.5 wt% to 3 wt%. Finally, the thermal performances were evaluated through differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The high thermal decomposition temperature of PB indicated that PB possessed possibility as a nucleating agent for PLLA, and the non-isothermal crystallization behavior confirmed the crystallization accelerating effectiveness of PB for PLLA. Upon optimum concentration of 2 wt%, the onset crystallization temperature, the crystallization peak temperature and the non-isothermal crystallization enthalpy increased from 101.4°C, 94.5°C and 0.1 J·g-1 to 121.3°C, 115.8°C and 35.1 J·g-1, respectively. In addition, the non-isothermal crystallization behavior was also affected by the cooling rate and the final melting temperature. The melting behavior further evidenced the advanced nucleating ability of PB, and the competitive relationship between PB and the heating rate, the nuclear rate and crystal growth rate. Thermal stability measurement showed that PB with a concentration of 1 wt%–2 wt% could slightly improve the thermal stability of PLLA.

Synthesis of Rod-Like Porous MgFe2O4 Architectures as a Catalyst for Ammonium Perchlorate Thermal Decomposition

NANO ◽  
2018 ◽  
Vol 13 (06) ◽  
pp. 1850069 ◽  
Author(s):  
Run Chen ◽  
Gang Li ◽  
Weiyang Bai ◽  
Shuang Bao ◽  
Zhiliang Cheng
Keyword(s):  
Thermal Decomposition ◽  
Ammonium Perchlorate ◽  
Raw Materials ◽  
Decomposition Temperature ◽  
Scanning Calorimetry ◽  
Oxalate Precursor ◽  
Highly Active ◽  
Composite Solid Propellant ◽  
Composite Solid

The development of highly active catalysts for the pyrolysis of ammonium perchlorate (AP) is of considerable importance for AP-based composite solid propellant. In the present study, we produced porous MgFe2O4 architectures by using a facile two-step strategy. A rod-like precursor of MgFe2(C2O[Formula: see text]O (diameter: 0.5–2.5[Formula: see text][Formula: see text]m; length: 2–15[Formula: see text][Formula: see text]m) was fabricated under solvothermal conditions using metal sulfates as raw materials and oxalic acid as the precipitant. Subsequently, porous MgFe2O4 architectures were obtained by the thermal treatment of the as-prepared oxalate precursor, during which the mesopores were formed in situ via the liberation of volatile gases, while the rod-like morphology was well preserved. The catalytic performances of the as-synthesized porous rod-like MgFe2O4 architectures with respect to the AP pyrolysis were assessed using differential scanning calorimetry (DSC) techniques. The results indicated that the high thermal decomposition temperature and the apparent activation energy of AP with 2[Formula: see text]wt.% MgFe2O4 addition decreased from 445.4[Formula: see text]C to 386.7[Formula: see text]C and from [Formula: see text] to [Formula: see text][Formula: see text]kJ mol[Formula: see text], respectively. Meanwhile, the decomposition heat of AP with MgFe2O4 as the additive reached up to 1230.6[Formula: see text]J g[Formula: see text], which was considerably higher than that of its neat counterpart (695.8[Formula: see text]J g[Formula: see text]. Thus, porous rod-like MgFe2O4 architectures could be served as the catalyst for the AP pyrolysis.

Sign in / Sign up

Export Citation Format

Share Document