Journal articles: 'Thermal decomposition (TG, DTG, SDTA)'

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Zhang, Wei, Yang Zang, Yanli Lu, Weisheng Lin, Shengyun Zhao, and Jinping Xiong. "Thermal Decomposition of Brominated Butyl Rubber." Materials 14, no. 22 (November 10, 2021): 6767. http://dx.doi.org/10.3390/ma14226767.

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The thermal decomposition of brominated butyl rubber under air atmosphere was investigated by thermogravimetry (TG) and derivative thermogravimetry (DTG) at various heating rates. The kinetic parameters were evaluated by TG and the isoconversional method developed by Ozawa. One prominent decomposition stage was observed in the DTG curves at high heating rates, while an additional small peak was observed at low heating rates. The apparent activation energy determined using the TG method ranged from 219.31 to 228.13 kJ·mol−1 at various heating rates. The non-isothermal degradation was found to be a first-order reaction, and the activation energy, as determined by the isoconversional method, increased with an increase in mass loss. The kinetic data suggest that brominated butyl rubber has excellent thermal stability. This study can indirectly aid in improving rubber pyrolysis methods and in enhancing the heat resistance of materials.

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Wen, Pu Hong. "Kinetic Investigation of Thermal Decomposition Reactions of 4'-Demethypodophyllotoxin and Podophyllotoxin." Advanced Materials Research 800 (September 2013): 517–21. http://dx.doi.org/10.4028/www.scientific.net/amr.800.517.

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The thermal behavior and thermal decomposition kinetic parameters of podophyllotoxin (PPT) and 4-demethypodophyllotoxin (DMPPT) in a temperature-programmed mode have been investigated by means of DSC and TG-DTG. The kinetic model functions in differential and integral forms of the thermal decomposition reactions mentioned above for leading stage were established. The kinetic parameters of the apparent activation energy Ea and per-exponential factor A were obtained from analysis of the TG-DTG curves by integral and differential methods. The most probable kinetic model function of both decomposition reactions in differential form was (1-α) 2. The values of Ea indicated that the reactivity of PPT was higher than that of DMPPT in the thermal decomposition reaction. The values of the entropy of activation ΔS≠, enthalpy of activation ΔH≠ and free energy of activation ΔG≠ of the reactions were estimated.

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Nguyen, Trung Toan, Duc Nhan Phan, Van Thom Do, and Hoang Nam Nguyen. "Kinetic Analysis of the Thermal Decomposition of Polymer-Bonded Explosive Based on PETN: Model-Fitting Method and Isoconversional Method." Advances in Materials Science and Engineering 2020 (July 11, 2020): 1–12. http://dx.doi.org/10.1155/2020/9260818.

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This work investigates kinetics and thermal decomposition behaviors of pentaerythritol tetranitrate (PETN) and two polymer-bonded explosive (PBX) samples created from PETN (named as PBX-PN-85 and PBX-PP-85) using the vacuum stability test (VST) and thermogravimetry (TG/DTG) techniques. Both model-free (isoconversional) and model-fitting methods were applied to determine the kinetic parameters of the thermal decomposition. It was found that kinetic parameters obtained by the modified Kissinger–Akahira–Sunose method (using non-isothermal TG/DTG data) were close to those obtained by the isoconversional and model-fitting methods that use isothermal VST data. The activation energy values of thermal decomposition reactions were 125.6–137.1, 137.3–144.9, and 143.9–152.4 kJ·mol−1 for PBX-PN-85, PETN, and PBX-PP-85, respectively. The results demonstrate the negative effect of the nitrocellulose-based binder in reducing the thermal stability of single PETN, while the polystyrene-based binder seemingly shows no adverse influence on the thermal decomposition of PETN in our presented PBX compositions.

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Wen, Pu Hong. "Kinetic Investigation of Thermal Decomposition Reactions of Podophyllic Acid and Picropodophyllic Acid." Advanced Materials Research 391-392 (December 2011): 1230–34. http://dx.doi.org/10.4028/www.scientific.net/amr.391-392.1230.

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The thermal behavior and thermal decomposition kinetic parameters of podophyllic acid and picropodophyllic acid in a temperature-programmed mode have been investigated by means of DSC and TG-DTG. The kinetic model functions in differential and integral forms of the thermal decomposition reactions mentioned above for leading stage were established. The kinetic parameters of the apparent activation energy Ea and per-exponential factor A were obtained from analysis of the TG-DTG curves by integral and differential methods. The most probable kinetic model function of the decomposition reaction in differential form was 2/3•α-1/2 for podophyllic acid and 1/2• (1-α)-1 for picropodophyllic acid. The values of Ea indicated that the reactivity of picropodophyllic acid was highter than that of podophyllic acid in the thermal decomposition reaction. The values of the entropy of activation ΔS≠, enthalpy of activation ΔH≠ and free energy of activation ΔG≠ of the reactions were estimated.

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Wen, Pu Hong. "Kinetic Investigation of Thermal Decomposition Reaction of Ethane-1,2-Diamine Copper(II) Chloride, C₂H₈N₂CuCl₂." Applied Mechanics and Materials 665 (October 2014): 255–59. http://dx.doi.org/10.4028/www.scientific.net/amm.665.255.

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:The thermal behavior and thermal decomposition kinetic parameters of ethane-1,2-diamine copper (II) chloride (EDCC) in a temperature-programmed mode have been investigated by mean of TG-DTG. There are four stages in the thermal decomposition process. The kinetic parameters of the apparent activation energyEa(130.2, 143.6 and 158.9 KJ·mol–1) and per-exponential factorA(1011.80, 1012.18and 1011.83s–1) in II, III and IV stages were obtained from analysis of the TG-DTG curves by Kissinger method. The values ofEaindicated that the difficulty coefficient of pyrolysis in II, III and IV stages was increased in the order: II < III < IV. The values of the entropy of activation ΔS≠, enthalpy of activation ΔH≠and free energy of activation ΔG≠of the reaction were estimated.

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Kaczmarska, Karolina, Sylwia Żymankowska-Kumon, Łukasz Byczyński, Beata Grabowska, Artur Bobrowski, and Sylwia Cukrowicz. "Thermoanalytical studies (TG–DTG–DSC, Py–GC/MS) of sodium carboxymethyl starch with different degrees of substitution." Journal of Thermal Analysis and Calorimetry 138, no. 6 (November 2, 2019): 4417–25. http://dx.doi.org/10.1007/s10973-019-08892-4.

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Abstract The paper presents the results of thermal analysis of polymer material in the form of starch derivatives in the form of sodium carboxymethyl starch (CMS–Na) with degree of substitution (DS) in the range 0.2–0.9 for the preparation of foundry binder. In this work, the thermal behavior of the modified starch and qualitative assessment of degradation products released during pyrolysis were determined and comprised. The analysis of the course of progressive decomposition of the starch material under controlled heating in the range of 25–1000 °C in anaerobic atmosphere was based on the results of thermal analysis methods (TG–DTG–DSC) in combination with the results of pyrolysis–gas chromatography–mass spectrometry (Py–GC/MS). The detailed TG–DTG–DSC analysis allowed to determine and compare the temperature at which the process of decomposition of carboxymethyl starches sodium salts with different degrees of substitution begins and to determine the course of its degradation under conditions corresponding to the contact of the foundry binder in the form of starch material with liquid metal (conditions like in foundry mold). Thermogravimetric analysis shows that decomposition processes are multistage, and dehydration is the first step of decomposition. Moreover, TG–DTG–DSC analyses indicate that the thermal stability and the decomposition path of tested compounds depend on the DS. Results of Py–GC/MS studies showed that the formation of decomposition products (including cyclic and aromatic hydrocarbons) in a predetermined temperature range is lower in the case of CMS–Na with high DS.

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He, Xiao Fang, Chang Wen Miao, Yong Hao Wu, Xin Xin Cao, and Dan Liu. "Thermal Reaction Kinetics of Fly Ash Cement Paste at the Age of 28 Days." Applied Mechanics and Materials 668-669 (October 2014): 91–94. http://dx.doi.org/10.4028/www.scientific.net/amm.668-669.91.

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The thermal reaction kinetics of fly ash cement pastes were studied by Differential Scanning Calorimetry (DSC) and Thermal Gravity Analysis-Differential Thermal Gravity (TG-DTG) method, the kinetics parameters such as apparent activation energy was calculated by the Kissinger method, and the physical parameters were obtained. The result show that the fly ash cement pastes performance three endothermic reaction stages at different heating rates, peak temperatures of each stage at the range of 91.85~121.08°C, 453.93~496.48°C, and 680.21~751.62°C. TG-DTG show there were three thermal decomposition stages, thermal dehydration reaction apparent activation energy of fly ash cement pastes in each stage were 47.23kJ/mol, 128.84kJ/mol, and 134.07kJ/mol.

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Li, Dong Yang, Xian Guo Li, Li Juan Feng, and Chuan Hui Gao. "One-Step Hydrothermal Synthesis of Magnesium Hydroxide Sulfate Hydrate Whiskers Using Brine as Raw Material." Advanced Materials Research 233-235 (May 2011): 2545–48. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.2545.

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Magnesium hydroxide sulfate hydrate (MHSH) whiskers were prepared using brine, sodium hydroxide and sodium sulfate as raw materials by one-step hydrothermal process. X-ray powder diffraction (XRD), thermal analysis (TG-DTG) and scanning electron microscope (SEM) were employed to characterize the MHSH whiskers. It was shown that the MHSH whiskers were MgSO4•5Mg(OH)2 •2H2O with a diameter of 0.2–0.3 μm and a length of 20–30 μm . The thermal decomposition of MHSH whisker was demonstrated a three-step scheme based on the TG-DTG data. The utilization ratio of magnesium in brine was above 80%.

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Song, Jun, Wen Long Jian, and Li Wang. "Study on Thermal Analysis Kinetics of Carbon Support." Advanced Materials Research 750-752 (August 2013): 1322–25. http://dx.doi.org/10.4028/www.scientific.net/amr.750-752.1322.

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Actived carbon can be widely used as adsorbent, catalyst and catalyst support for many chemical reactions. At present, the research on thermal analysis Kinetics of actived carbon is quite few.Studing on it,is helpful for disclosing the decomposition reaction process and thermodynamic law of actived carbon. By thermal analysis, thermal decomposition Characteristics of actived carbon is studied. The TG and DTG eurves of actived carbon were obtain ed using multiple heating rate method.The test data were processed by iso-conversional method to obtain the kinetic parameters.The results showed that, with the improving of heating rate , the startimg reaction temperature of TG and the peak temperature of DTG shifted to the high temperature zone, postponement phenomena occurred.Based on the collected experimental data, it proved that had better linear relations with . The activation energy E of decomposition reaction of actived carbon, which was determined by measurements of slope, was 96.59kJ/mol. The plot of vs was drew and a straight line was obtained. .The mechanism function was defined as ,so according to the slope and intercept of the line,it can be obtained that n=3.585,A=40189.85984.

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MATHEW, VARGHESE, JOCHAN JOSEPH, SABU JACOB, LIZYMOL XAVIER, and K. E. ABRAHAM. "SPECTROSCOPIC AND THERMAL STUDIES OF GEL-GROWN COPPER MALONATE CRYSTALS." Modern Physics Letters B 24, no. 11 (May 10, 2010): 1135–43. http://dx.doi.org/10.1142/s0217984910023177.

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Copper malonate crystals were grown using silica gel as the growth medium. The grown crystals were characterized by X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR) and Fourier transform Raman spectroscopy (FT Raman). The thermal decomposition of the compound was investigated using thermogravimetry (TG) and derivative thermogravimetry (DTG) measurements.

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Petrunina, Elena Alexandrovna, OlgaOlga Aleksandrovna Shapchenkova, and SergeySergey Redzhinaldovich Loskutov. "PHYSICO-CHEMICAL PARAMETERS OF SIBERIAN LARCH (LARIX SIBIRICA) BARK EXTRACTED WITH WATER-AMINO-ALCOHOLIC EXTRACTANTS." chemistry of plant raw material, no. 2 (June 10, 2021): 103–7. http://dx.doi.org/10.14258/jcprm.2021028340.

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This paper presents the results of a thermal analysis, that involved thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC), of natural bark of Siberian larch (Larix sibirica Ldb.) vs. the bark extracted with 5% water-monoethanolamine (MEA) and (vs.) 5% water-triethanolamine (TEA). Thermogravimetric data obtained in an oxidative (air) atmosphere allowed us to identify temperature ranges of thermal decomposition stages for the larch bark samples, as well as to determine the corresponding mass loss and mass loss rate at programmed heating. The Ozawa-Flynn-Wall (OFW) method was used to calculate the dependence of activation energy of the thermal decomposition of experimental samples on the conversion degree (Еа = f(a)); the symbate run of Еа = f(a) curves was established. The DSC data obtained agreed with those of TG/DTG. The integral heat of the bark thermal decomposition (9.60 kJ/g and 14.12 kJ/g for MEA and TEA, respectively) indicated the bark to be competitive with other biofuels, such as briquetted lignin, wood pellets, sunflower husk, rapeseeds, and straw.

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Bannach, G., E. Schnitzler, C. B. Melios, and M. Ionashiro. "Synthesis and thermal studies of solid state 2-chloro-benzylidenepyruvic acid and its compounds with sodium, aluminium (III), gallium (III) and indium (III) cations." Eclética Química 29, no. 1 (2004): 31–40. http://dx.doi.org/10.1590/s0100-46702004000100004.

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The synthesis of sodium 2-chlorobenzylidenepyruvate and its corresponding acid as well as binary, binary together with it's acid or hydroxo-2-chorobenzylidenepyruvate of aluminium (III), gallium (III) and indium (III), were isolated. Chemical analysis, thermogravimetry, derivative thermogravimetry (TG/DTG), simultaneous thermogravimetry-differential thermal analysis (TG-DTA) and X-ray powder diffractometry have been employed to characterize and to study the thermal behaviour of these compounds. The results provided information concerning the stoichiometry, crystallinity, thermal stability and thermal decomposition.

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Liu, Ling, Zheng Xing, Yi Xiang Liu, and Hua Yi. "Study of Influence Factors on Medium-Density Fiberboard Thermal Analysis." Advanced Materials Research 1095 (March 2015): 468–70. http://dx.doi.org/10.4028/www.scientific.net/amr.1095.468.

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The main influence factors on thermal analysis of medium-density fiberboard (MDF) was analyzed by thermo-gravimetry (TG) and derivative thermo-gravimetry (DTG) , which are heating rate, atmosphere and sample . Results showed that heating rate affected the thermo-decomposition obviously, while the effect on the residual charcoal was small, The results can provide reference to extinguishment and fire investigation.

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CEGŁA, Marcin, Janusz ZMYWACZYK, and Piotr KONIORCZYK. "Analysis of Thermal Decomposition of Solid Rocket Propellants." Problems of Mechatronics Armament Aviation Safety Engineering 10, no. 2 (June 30, 2019): 43–54. http://dx.doi.org/10.5604/01.3001.0013.2115.

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The paper presents results of thermal decomposition analysis of selected solid rocket propellants. Homogeneous propellant PAC and heterogeneous propellant H2 were subjected to simultaneous thermal analysis with the use of NETZSCH STA 2500 Regulus device with five heating rates of 2.5, 5, 7.5, 10 and 15 K/min. The method combines TG, DTG and DTA analytical techniques in a single measurement. The aim of the conducted experiments was to study thermal decomposition of these energetic materials as well as to determine activation energy of the decomposition process and the preconditioning factor from the TG curves. The tested materials properties and chemical composition along with a brief description of the experimental procedure are described. The inverse procedure of calculating the activation energy, based on the Ozawa-Flynn-Wall model is described. Finally, the results of thermal decomposition of two tested solid rocket propellants are presented along with maximum decomposition rates and percentage of mass loss.

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CHAHUD, Marisa, Marco Aurélio da Silva CARVALHO FILHO, Nedja Suely FERNANDES, and Massao IONASHIRO. "A thermal analysis study of dithizone and dithizonates of mercury, silver and bismuth." Eclética Química 25 (2000): 9–17. http://dx.doi.org/10.1590/s0100-46702000000100001.

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Solid dithizonates of Hg(I), Ag(I) and Bi(III) have been prepared. Thermogravimetry (TG), derivative thermogravimetry (DTG), differential scanning calorimetry (DSC), X ray diffraction powder patterns and elemental analysis have been used to characterize and to study the thermal stability and thermal decomposition of the dithizone and of these dithizonates.

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CARVALHO FILHO, Marco Aurélio da Silva, and Massao IONASHIRO. "Thermal behaviour study of solid state compounds of manganese (II), zinc (II) and lead (II) with cinnamic acid." Eclética Química 23 (1998): 09–16. http://dx.doi.org/10.1590/s0100-46701998000100001.

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Compounds of cinnamic acid with manganese, zinc and lead have been prepared in aqueous solution. Thermogravimetry, derivative thermogravimetry (TG, DTG), differential scanning calorimetry (DSC), X-ray diffraction and complexometry have been used in the characterization as well as in the study of the thermal stability and interpretation concerning the thermal decomposition.

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Guo, Kai, Xiao Qing Shen, Yuan Yuan Zhan, Jin Zhou Chen, Ming Jun Niu, Yu Kun Liu, and Xin Fa Li. "Thermal Decomposition Kinetics of PLLA/Talc/TBC Composites." Applied Mechanics and Materials 262 (December 2012): 572–76. http://dx.doi.org/10.4028/www.scientific.net/amm.262.572.

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To enhance the crystallizability and flexibility, Poly L-lactide (PLLA)/ Talc/ tributyl citrate(TBC) composites were prepared via melt extrusion and investigated by thermogravimetry (TG) and derivative thermogravimetry (DTG). It was shown that the thermal decomposition temperature of PLLA/Talc (97:3) and of PLLA/Talc/TbC (96:3:1) had increased 7.6 oC and 16.2 oC respetively compared with pure PLLA. The thermal decomposition kinetics of pure PLLA and composites were studied by using the Ozawa–Flynn–Wall (OFW) and the Friedman methods respectively, the results indicated that the apparent activation energies of PLLA/Talc/TBC composites increased sharply in the initial stage of the mass loss.

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Carvalho, C. T., A. B. Siqueira, E. C. Rodrigues, and M. Ionashiro. "Synthesis, characterization and thermal behaviour of solid-state compounds of 2-methoxybenzoate with some bivalent transition metal ions." Eclética Química 30, no. 4 (2005): 19–26. http://dx.doi.org/10.1590/s0100-46702005000400003.

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Solid-state M-2-MeO-Bz compounds, where M stands for bivalent Mn, Co, Ni, Cu and Zn and 2-MeO-Bz is 2-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry-differential thermal analysis (TG-DTA), thermogravimetry, derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to have information about the composition, dehydration, thermal stability and thermal decomposition of the isolated compounds.

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Qu, Hong Qiang, Wei Hong Wu, Chun Zheng Wang, Xin Liu, and Chun Meng Yin. "Thermal Decomposition of Wood Treated with Silicates by Thermogravimetry–Mass Spectrometry." Advanced Materials Research 239-242 (May 2011): 459–62. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.459.

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The thermal decomposition of wood treated with a series of silicates was characterized by thermogravimetric (TG) analysis, differential thermogravimetry (DTG), and thermogravimetry–mass spectrometry (TG–MS) analysis. The addition of these chemicals caused a decrease in the decomposition temperature, a reduction in weight loss, and an increase in the amount of char produced. The results showed that ion current intensity and ion peak area of the typical representatives of incombustible ion such as m/z = 18 and 44 MS signals were increased by the flame retardants but the inflammable ion such as m/z =12 and 28 MS signals were decreased at the meantime, which indicate that the flame retardants can significantly enhances the dehydration and inhibits the deploymerisation reaction of wood.

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Wzorek, Małgorzata, Robert Junga, Ersel Yilmaz, and Bohdan Bozhenko. "Thermal Decomposition of Olive-Mill Byproducts: A TG-FTIR Approach." Energies 14, no. 14 (July 8, 2021): 4123. http://dx.doi.org/10.3390/en14144123.

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In this study, the combustion of olive byproducts was investigated using the TG-FTIR technique. Different types of olive biomass were considered: twigs, leaves, olive-mill waste from the two-phase decanting method, and wastewater from the three-phase system. The reaction regions, ignition, and burnout temperatures at different heating rates were determined using TG/DTG analysis and the thermogravimetry results. Comprehensive combustion, ignition, burnout, and flammability indexes were also calculated. The highest combustion index values were obtained for waste from the three-phase system, followed by the two-phase decanting method, then with leaves and small twigs. The order of the index values indicated that the sample from the three-phase process ignited more quickly and yielded faster. The changes in activation energy calculated using different model-free isoconversional methods—Friedman, Ozawa–Flynn–Wall, and Kissinger–Akahira–Sunose—fell within the range of 130–140 kJ/kmol. FTIR analyses presented differences in the exhaust gas composition for specific combustion temperature ranges.

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Chen, Tao, Hong Xing Gui, Yong Zhou Wang, Hong Hai Huang, Ri Zhong Zeng, and Mao Fang Huang. "Effect of CMCS on the Thermal Stability of Natural Rubber." Advanced Materials Research 534 (June 2012): 25–29. http://dx.doi.org/10.4028/www.scientific.net/amr.534.25.

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Effect of CMCS on the thermal stability of natural rubber(NR) was studied by means of TG-DTG,and the decomposition activation energy(Ea) was calculated through Flynn–Wall–Ozawa (FWO) method in the paper.The results showed that the Ea of NR mixed with CMCS was higher than that of ammonification NR,and the thermal stability of NR improved with increasing the addition level of CMCS.

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Yao, Xiang, Shuai Zhang, and Bo Sun. "Thermal Analysis of Coal-Bearing Strata Kaolinite/potassium Acetate Intercalation Complex." Advanced Materials Research 538-541 (June 2012): 2077–81. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.2077.

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The thermal decomposition of coal-bearing strata kaolinite-potassium acetate(CK/KAc) intercalation complex has been studied using X-ray diffraction (XRD), thermogravimetry and differential thermogravimetric (TG-DTG) and infrared emission spectroscopy (IES). The XRD results show that the KAc has been successfully intercalated into coal-bearing strata kaolinite with an obvious basal distance increase of the first basal peak. The TG results show that the thermal decomposition of the intercalation complex occurs in four main steps (a) the loss of adsorbed water (b) the loss of coordination water (c) the loss of potassium acetate and (d) water through dehydroxylation. The IES of CK/KAc give the evidence on the changes of structure. These make all explanation have the sufficient evidence.

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Gao, Yan, Tao Luan, Tao Lv, and Hong Ming Xu. "The Mo Loading Effect on Thermo Stability and SO₂Oxidation of SCR Catalyst." Advanced Materials Research 573-574 (October 2012): 58–62. http://dx.doi.org/10.4028/www.scientific.net/amr.573-574.58.

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The SCR catalysts were produced with V2O5, WO3, MoO3 and anatase type TiO2. The thermo stability of the catalyst with different MoO3 loading was analyzed with TG-DTG. And the SO2 oxidations were researched with a fixed bed reactor under simulated exhaust gas. The different loadings of MoO3 did not effect on the thermo stability of the catalyst with temperature in the test range of 30~1000 °C. The TG–DTG curves of thermal decomposition process of V2O5-WO3-MoO3/TiO2 catalyst showed three mass loss segments: 1st the evaporation of crystal water from 70 °C to 130 °C; 2nd the decomposition of organics from 180 °C to 350 °C; 3rd the decomposition of impurities from 480 °C to 550 °C. The catalyst loading MoO3 showed higher catalytic selectivity compared to the catalysts without MoO3. MoO3 contained in the catalysts prevented SO2 oxidation, improving the oxidation start temperature and reducing the maximum oxidation.

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ZAINA CHIARETTO, Ana Glauce, Marco Aurélio da Silva CARVALHO FILHO, Nedja Suely FERNANDES, and Massao IONASHIRO. "Preparation and thermal decomposition of solid state cinnamates of alkali earth metals, except beryllium and radium." Eclética Química 23 (1998): 91–98. http://dx.doi.org/10.1590/s0100-46701998000100008.

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Solid state compounds of general formula ML2.nH2O [where M is Mg, Ca, Sr or Ba; L is cinnamate (C6H5 -CH=CH-COO-) and n = 2, 4, 0.8, 3 respectively], have been synthetized. Thermogravimetry (TG), derivative thermogravimetry (DTG), differential scanning calorimetry (DSC) and X-ray diffraction powder patterns have been used to characterize and to study the thermal stability and thermal decomposition of these compounds.

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Linghu, Wen Sheng, and Chun Yan Sun. "A Study on the TG/DTA Behavior of Decabromodiphenyl Ether." Advanced Materials Research 850-851 (December 2013): 177–80. http://dx.doi.org/10.4028/www.scientific.net/amr.850-851.177.

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In this work, the TG/DTA behavior of decabromodiphenyl ether (BDE-209) at nitrogen and air atmosphere by using a thermogravimetric analyzer was investigated. The results showed that both of TG and DTG curves at nitrogen atmosphere are very similarly with that at air atmosphere. About 75 wt% and 25 wt% of total mass loss were observed at the temperature range of about 300-430 °C and about 430-580°C, respectively. It is indicated that the mass loss of BDE-209 during the thermal treamtnet is mainly caused by the evaporation and thermal decomposition.

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Nyakuma, Bemgba Bevan, and Aliyu Jauro. "Physicochemical Characterization and Thermal Decomposition of Garin Maiganga Coal." GeoScience Engineering 62, no. 3 (December 1, 2016): 6–11. http://dx.doi.org/10.1515/gse-2016-0018.

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Abstract The paper examined physicochemical and thermal characteristics of the newly discovered Garin Maiganga (GMG) coal from Nigeria. The physicochemical characterization comprised of elemental, proximate, calorific value, and classification (rank) analyses. Thermal analysis was examined using combined Thermogravimetric (TG) and Derivative Thermogravimetric analyses (DTG). Hence, the coal was heated from 30°C to 1000°C at 20°C/min under inert conditions to examine its thermal degradation behaviour and temperature profile characteristics (TPC). The results indicated that the GMG coal fuel properties consist of low Ash, Nitrogen, and Sulphur content. Moisture content was > 5%, Volatile Matter > 50%, Fixed Carbon > 22%, and Heating Value (HHV) 23.74 MJ/kg. Based on its fuel properties, the GMG coal can be classified as a Sub-Bituminous B, non-agglomerating low rank coal (LRC). The GMG coal TPCs – onset, peak, and offset temperatures – were 382.70°C, 454.60°C, and 527.80°C, respectively. The DTG profile revealed four (4) endothermic peaks corresponding to loss of moisture (drying), volatile matter (devolatization), and coke formation. The residual mass Rm was 50.16%, which indicates that higher temperatures above 1000°C are required for the complete pyrolytic decomposition of the GMG coal. In conclusion, the results indicate that the GMG coal is potentially suitable for future utilization in electric power generation and the manufacture of cement and steel.

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Siqueira, A. B., C. T. de Carvalho, E. C. Rodrigues, E. Y. Ionashiro, G. Bannach, and M. Ionashiro. "Synthesis, characterization and thermal behaviour on solid pyruvates of light trivalent lanthanides." Eclética Química 32, no. 4 (2007): 49–54. http://dx.doi.org/10.1590/s0100-46702007000400007.

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Solid State Ln-L compounds, where Ln stands for light trivalent lanthanides (La - Gd) and L is pyruvate, have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-Ray powder diffractometry, infrared spectroscopy, elemental analysis, and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, ligand denticity, thermal behaviour and thermal decomposition of the isolated compounds.

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SCHNITZLER, Egon, Wilson COSTA, Cristo Bladimiros MELIOS, Maria Ines Gonçalves LELES, and Massao IONASHIRO. "Thermal behavior studies of solid state compounds of 4-dimethylaminocinnamylidenepyruvate with alkali earth metals, except beryllium and radium." Eclética Química 25 (2000): 31–39. http://dx.doi.org/10.1590/s0100-46702000000100003.

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Solid state compounds of general formula M(DMCP)2.nH2O, where M represents Mg, Ca, Sr, Ba, and DMCP is 4-dimethylaminocinnamylidenepyruvate, and n = 1, except for Ca, where n = 2.5, have been prepared. Thermogravimetry, derivative thermogravimetry (TG, DTG), differential scanning calorimetry (DSC), X-ray diffraction powder patterns and complexometry were used to characterize and to study the thermal decomposition of these compounds.

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LELES, Maria Ines Gonçalves, Cristo Bladimiros MELIOS, Lázaro Moscardini D’ASSUNÇÃO, and Massao IONASHIRO. "Preparation and thermal behavior of mixture of basic carbonate and 4-dimethylaminocinnamylidenepyruvate with lanthanides (III) and yttrium (III) in the solid state." Eclética Química 24 (1999): 29–44. http://dx.doi.org/10.1590/s0100-46701999000100003.

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Solid Ln-OHCO3-DMCP compounds, where Ln represents lanthanides (III) and yttrium (III) ions and DMCP is the anion 4-dimethylaminocinnamylidenepyruvate, have been prepared. Thermogravimetry, derivative thermogravimetry (TG, DTG), differential scanning calorimetry (DSC), x-Ray diffraction powder patterns and elemental analysis have been used to characterize the compounds. The thermal stability as well as the thermal decomposition of these compounds were studied using an alumina crucible in an air atmosphere.

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Bi, Ai Hong, and Jin Hua Zhu. "Syntheses and Thermo-Decomposition Process of the Co-Doping VO₂(M) Precursor." Materials Science Forum 663-665 (November 2010): 1289–92. http://dx.doi.org/10.4028/www.scientific.net/msf.663-665.1289.

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The precursor doped with W6+ and Mo6+ ionic was prepared using oxalic acid as reduction acid, V2O5 as vanadium source, (NH4)6W7O24·6H2O and (NH4)6Mo7O24·4H2O as doped sources. The morphology, composition, structure and the thermo-decomposing process of the precursor were characterized by means of SEM, EDS, FTIR and DSC/TG/DTG. The thermal decomposition was confirmed by XRD.

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31

Siqueira, A. B., C. T. de Carvalho, E. Y. Ionashiro, and M. Ionashiro. "Synthesis, characterization and thermal behaviour on solid pyruvates of some bivalent metal ions." Eclética Química 34, no. 2 (2009): 15–21. http://dx.doi.org/10.1590/s0100-46702009000200002.

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Solid state M-L compounds, were M stands for bivalent Mn, Fe, Co, Ni, Cu, Zn and L is pyruvate, have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-Ray powder diffractometry, infrared spectroscopy, elemental analysis, and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, ligand denticity, and thermal decomposition of the isolated compounds.

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De Siqueira, Adriano Buzutti, Cláudio Teodoro De Carvalho, Elias Yuki Ionashiro, and Massao Ionashiro. "Synthesis, characterization and thermal behaviour on solid pyruvates of some bivalent metal ions." Eclética Química Journal 34, no. 2 (January 24, 2018): 15. http://dx.doi.org/10.26850/1678-4618eqj.v34.2.2009.p15-21.

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Solid state M-L compounds, were M stands for bivalent Mn, Fe, Co, Ni, Cu, Zn and L is pyruvate, have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-Ray powder diffractometry, infrared spectroscopy, elemental analysis, and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, ligand denticity, and thermal decomposition of the isolated compounds.

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Karapınar, Emin, Ilkay Hilal Gubbuk, Bilge Taner, Pervin Deveci, and Emine Ozcan. "Thermal Degradation Behaviour of Ni(II) Complex of 3,4-Methylenedioxaphenylaminoglyoxime." Journal of Chemistry 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/548067.

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Thermal degradation behaviour of the Ni(II) complex of 3,4-methylenedioxaphenylaminoglyoxime was investigated by TG, DTA, and DTG at a heating rate of 10°C min−1under dinitrogen. The acquired experimental data shows that the complex is thermally stable up to 541 K. The pyrolytic decomposition process occurs by melting metal complex and metal oxide remains as final product. The energies of the reactions involved and the mechanism of decomposition at each stage have been examined. The values of kinetic parameters such as activation energy (E), preexponential factor (A) and thermodynamic parameters such as enthalpy (ΔH), entropy (ΔS), and Gibbs free energy (ΔG) are also evaluated.

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34

Yousef, Samy, Justas Eimontas, Nerijus Striūgas, Marius Praspaliauskas, and Mohammed Ali Abdelnaby. "Pyrolysis Kinetic Behaviour of Glass Fibre-Reinforced Epoxy Resin Composites Using Linear and Nonlinear Isoconversional Methods." Polymers 13, no. 10 (May 11, 2021): 1543. http://dx.doi.org/10.3390/polym13101543.

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Due to the increasing demand for glass fibre-reinforced epoxy resin composites (GFRC), huge amounts of GFRC waste are produced annually in different sizes and shapes, which may affect its thermal and chemical decomposition using pyrolysis technology. In this context, this research aims to study the effect of mechanical pre-treatment on the pyrolysis behaviour of GFRC and its pyrolysis kinetic. The experiments were started with the fabrication of GFRC panels using the vacuum-assisted resin transfer method followed by crushing the prepared panels using ball milling, thus preparing the milled GFRC with uniform shape and size. The elemental, proximate, and morphology properties of the panels and milled GFRC were studied. The thermal and chemical decomposition of the milled GFRC was studied using thermogravimetric coupled with Fourier-transform infrared spectroscopy (TG-FTIR) at different heating rates. Meanwhile, the volatile products were examined using TG coupled with gas chromatography–mass spectrometry (GC-MS). The TG-FTIR and TG-GC-MS experiments were performed separately. Linear (Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Friedman) and nonlinear (Vyazovkin and Cai) isoconversional methods were used to determine the pyrolysis kinetic of the milled GFRC based on thermogravimetry and differential thermal gravimetry (TG/DTG). In addition, the TG/DTG data of the milled GFRC were fitting using the distributed activation energy model and the independent parallel reactions kinetic model. The TG results showed that GFRC can decompose in three stages, and the main decomposition is located in the range 256–500 °C. On the other hand, aromatic benzene and a C-H bond were the major functional groups in the released volatile components in FTIR spectra, while phenol (27%), phenol,4-(1-methylethyl) (40%), and p-isopropenylphenol (34%) were the major compounds in GC-MS analysis. Whereas, the kinetic results showed that both isoconversional methods can be used to determine activation energies, which were estimated 165 KJ/mol (KAS), 193 KJ/mol (FWO), 180 KJ/mol (Friedman), 177 KJ/mol (Vyazovkin), and 174 KJ/mol (Cai).

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35

Czylkowska, Agnieszka, Bartłomiej Rogalewicz, Anita Raducka, Natalia Błaszczyk, Tomasz Maniecki, Kinga Wieczorek, and Paweł Mierczyński. "Synthesis, Spectroscopic, Thermal and Catalytic Properties of Four New Metal (II) Complexes with Selected N- and O-Donor Ligands." Materials 13, no. 14 (July 20, 2020): 3217. http://dx.doi.org/10.3390/ma13143217.

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Four solid compounds with formulae: Co(OAc)2(Im)·H2O (I), Ni(OAc)2(Im)1.5·2H2O (II), Cu2(OAc)4(Im) (III) and Zn(OAc)2(Im)·H2O (IV) (where: Im = 1H-Imidazole) were prepared and characterized by chemical and elemental analysis, powder X-ray diffraction patterns and FTIR spectroscopy. Catalytic properties of each complex for styrene oxidation reaction were investigated. Furthermore, thermal properties of compounds were studied using the TG-DTG and DSC techniques under dry air atmosphere. Additionally, volatile thermal decomposition and fragmentation products were also investigated using the TG-FTIR spectra in air.

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36

Salehabadi, Ali, and Abu Bakar Mohamad. "Epoxidized Natural Rubber-Organomodified Montmorillonite Nanohybrids; Interaction and Thermal Decomposition." Materials Science Forum 756 (May 2013): 119–26. http://dx.doi.org/10.4028/www.scientific.net/msf.756.119.

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Nanohybrids, based on a modified natural rubber,Epoxidized Natural Rubber (ENR-50), and organomodified montmorillonite (MMT) containing alkyl ammonium, were prepared by solvent casting technique. Morphology and non-isothermal degradation of ENR-50 and various ENR/MMT nanohybrids were characterized by POM, SEM and TG-DTG. In the hybrid materials,an increase MMT loading in the ENR-50 increased the maximum decomposition temperature (Tmax) of thermal profiles. Kissinger and Ozawa plots deduced a trend of the decomposition activation energy, Ed, which is related to the agglomeration and heat transfer ability of MMT. A mechanism comprising of the degradation of ENR-50 via scission of epoxy-isoprene chains to shorter chains, ring opening reaction and the possible interactions of modified nanoclay and ENR-50 is discussed.

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37

Suman, Swapan, Santosh Kumar Rai, Anand Mohan Yadav, Awani Bhushan, Nomendra Tomar, Rajneesh Kumar Singh, Ansar Ali SK, and Anuj Kumar Mishra. "Influence of Thermal and Morphological Behaviour on Biomass Waste Materials during Pyrolysis." E3S Web of Conferences 321 (2021): 01005. http://dx.doi.org/10.1051/e3sconf/202132101005.

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Aim of this study to investigate the thermal and morphological behaviour of different types of biomass feedstock. For investigation of thermal behaviour we used thermo-gravimetric (TG) analysis and derivative thermo-gravimetric (DTG) analysis. The biomass feedstocks were conceded out under vigorous conditions using nitrogen gas at specific heating rates to gradient the temperature from 25°C to 1000°C. The derivative thermo-gravimetric (DTG) results show that thermal decomposition on these feedstocks. First-order reaction model were used to determine the kinetics parameters for the pyrolysis of biomass wastes. This study used Field Emission Scanning Electron Microscopy (FE-SEM) to observe surface morphology properties of the different biomass wastes. The FE-SEM images showed that clearly retained the fibrous structures in the biomass wastes and were rich in macro-pores.

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38

Li, Ru Lin, Lin Wang, and Gang Xue. "Study on Preparation, Biological Activity and Thermal Decomposition of N-Benzoyl-N＇-(4-Chlorobenzamido) Thiourea." Advanced Materials Research 236-238 (May 2011): 1914–18. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.1914.

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A novel compound N-benzoyl-N＇-(4-chlorobenzamido) thiourea was prepared from benzoyl isothiocyanate which was obtained from benzoyl chloride and potassium thiocyanate, and 4-chlorobenzoyl hydrazine which was obtained from ethyl 4-chlorobenzoate and hydrazine hydrate. IR,1H NMR,13C NMR and elemental analysis were utilized to determine the structure of the thiourea. The biological tests indicated that the target compound had antibacterial activity against bacillus subtilis and taphylo-coccus aurers. Meanwhile, the thermal stability was investigated by thermogrativity（TG） and differential thermogrativity (DTG). The results demonstrated there was one weight-loss in the thermal decomposition process. The thermal kinetics equation obtained describing the thermal decomposition process was expressed as .

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39

da Silva Morais, Crislene Rodrigues, Wilton Silva Lopes, A. G. de Souza, and P. D. Santa-Cruz. "Synthesis and Thermal Characterization of Luminescent Powers of Terbium (III) with Mixed Ligands." Materials Science Forum 498-499 (November 2005): 535–39. http://dx.doi.org/10.4028/www.scientific.net/msf.498-499.535.

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This work deals with the synthesis and thermal decomposition of complexes of general formula: Ln(ß-dik)3L (where Ln=Tb+3, ß-dik=4,4,4-trifluoro-1-phenyl-1,3- butanedione(btfa) and L=1,10-fenantroline(phen) or 2,2-bipiridine(bipy). The powders were characterized by melting point, FTIR spectroscopy, UV-visible, elemental analysis, scanning differential calorimeter(DSC) and thermogravimetry(TG). The TG/DSC curves were obtained simultaneously in a system DSC-TGA, under nitrogen atmosphere. The experimental conditions were: 0.83 ml.s-1 carrier gas flow, 2.0±0.5 mg samples and 10°C.min-1 heating rate. The CHN elemental analysis of the Tb(btfa)3bipy and Tb(btfa)3phen complexes, are in good agreement with the expected values. The IR spectra evinced that the metal ion is coordinated to the ligands via C=O and C-N groups. The TG/DTG/DSC curves of the complexes show that they decompose before melting. The profiles of the thermal decomposition of the Tb(btfa)3phen and Tb(btfa)3bipy showed six and five decomposition stages, respectively. Our data suggests that the thermal stability of the complexes under investigation followed the order: Tb(btfa)3phen < Tb(btfa)3bipy.

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AlObaid, Abeer A., Ahmed Boshaala, Younis O. Ben Amer, Abrahem F. Abrahem, Nabil Al-Zaqri, Mohammed Suleiman, Abdelkader Zarrouk, Nawaf Al-Maharik, Hussien A. Khamees, and Ismail Warad. "One Pot Ultrasonic Assisted {[Ni(tptz)Cl(H2O)2][Ni(tptz)(H2O)3]}-3Cl.5H2O Complex Formation Using Triazine Ligand, XRD/HSA-Interactions, and Spectral and Thermal Investigation." Crystals 11, no. 12 (November 27, 2021): 1474. http://dx.doi.org/10.3390/cryst11121474.

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Under room temperature ultrasonic conditions, mixing the neutral 2,4,6-tri(pyridin-2-yl)-1,3,5-triazine (tptz) ligand with Ni(II) salt resulted in the preparation of a unique {[Ni(tptz)Cl(H2O)2]-[Ni(tptz)(H2O)3]}3Cl.5H2O complex with two different nickel(II) centers in a high yield. The crystal structure of {[Ni(tptz)Cl(H2O)2][Ni(tptz)(H2O)3]}3Cl.5H2O revealed the existence of distorted octahedral around both Ni(II) centers. The complex structure was further supported by FT-IR, UV-Vis., CHN-EA, TGA and EDX. The computed HSA was also performed to support the XRD interaction types. The existence of the H2O molecules in the crystal lattice was examined by FT-IR and TG/DTG measurements that proved the presence of coordinated and uncoordinated water molecules. Moreover, the thermal stability of the desired complex was evaluated at open atmosphere via TG/DTG and showed stability up to ~400 °C and multistep thermal decomposition.

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41

Liao, Xiao Xue, Shuang Quan Liao, Bing Tang, Ming Chao Luo, Yan Fang Zhao, and Hai Sheng Tan. "Study on Thermal and Mechanical Properties of Natural Rubber Latex Modified by Trichlorobromomethane." Advanced Materials Research 295-297 (July 2011): 36–40. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.36.

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Natural rubber latex (NRL) modified by holgonated addition with trichlorobromomethane was prepared. The thermal properties of modified NRL were analyzed by thermogravimetric analysis (TG/DTG),differential scanning calorimetry (DSC) and dynamic mechanical analysis(DMA). The results showed that the thermal stability of modified NRL was lower than NRL and the thermal degradation of modified NRL was two-stage decomposition. With increasing of stress frequency, loss modulus and storage modulus of latex increased,while loss modulus and storage modulus of modified latex decreased,compared with NRL.

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42

Jamilatun, Siti, Budhijanto Budhijanto, Rochmadi Rochmadi, and Arief Budiman. "Thermal Decomposition and Kinetic Studies of Pyrolysis of Spirulina Platensis Residue." International Journal of Renewable Energy Development 6, no. 3 (November 6, 2017): 193. http://dx.doi.org/10.14710/ijred.6.3.193-201.

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Analysis of thermal decomposition and pyrolisis reaction kinetics of Spirulina platensis residue (SPR) was performed using Thermogravimetric Analyzer. Thermal decomposition was conducted with the heating rate of 10, 20, 30, 40 and 50oC/min from 30 to 1000oC. Thermogravimetric (TG), Differential Thermal Gravimetric (DTG), and Differential Thermal Analysis (DTA) curves were then obtained. Each of the curves was divided into 3 stages. In Stage I, water vapor was released in endothermic condition. Pyrolysis occurred in exothermic condition in Stage II, which was divided into two zones according to the weight loss rate, namely zone 1 and zone 2. It was found that gasification occurred in Stage III in endothermic condition. The heat requirement and heat release on thermal decomposition of SPR are described by DTA curve, where 3 peaks were obtained for heating rate 10, 20 and 30°C/min and 2 peaks for 40 and 50°C/min, all peaks present in Zone 2. As for the DTG curve, 2 peaks were obtained in Zone 1 for similar heating rates variation. On the other hand, thermal decomposition of proteins and carbohydrates is indicated by the presence of peaks on the DTG curve, where lignin decomposition do not occur due to the low lipid content of SPR (0.01wt%). The experiment results and calculations using one-step global model successfully showed that the activation energy (Ea) for the heating rate of 10, 20, 30, 40 and 50oC/min for zone 1 were 35.455, 41.102, 45.702, 47.892 and 47.562 KJ/mol, respectively, and for zone 2 were 0.0001428, 0.0001240, 0.0000179, 0.0000100 and 0.0000096 KJ/mol, respectively.Keywords: Spirulina platensis residue (SPR), Pyrolysis, Thermal decomposition, Peak, Activation energy.Article History: Received June 15th 2017; Received in revised form August 12th 2017; Accepted August 20th 2017; Available onlineHow to Cite This Article: Jamilatun, S., Budhijanto, Rochmadi, and Budiman, A. (2017) Thermal Decomposition and Kinetic Studies of Pyrolysis of Spirulina platensis Residue, International Journal of Renewable Energy Development 6(3), 193-201.https://doi.org/10.14710/ijred.6.3.193-201

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Pan, Feng, Zai Yuan Li, and Chun Ji Li. "Study on Thermal Decomposition Kinetics of Nano-Cr(OH)₃Powder." Applied Mechanics and Materials 692 (November 2014): 377–80. http://dx.doi.org/10.4028/www.scientific.net/amm.692.377.

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Abstract. This paper studies on the thermal decomposition analysis kinetics of nanometer powders. The DTA-TG-DTG curves obtain by SDT 2960 Simultaneous DSC-TGA analysis apparatus. Under the condition of N2atmosphere operation and rise temperature velocity was 10°C·min-1. The mechanism function dα/dt=κ(1-α)nis used to calculate the kinetics factors. Reaction progressionnwas obtained by calculation of the kissinger peak shape factor method. The results showed that the apparent activation energy of nano-Ni(OH)2was 254.027 KJ·mol-1, the pre-exponential factor was 3.062×1036, the reaction progression was obtained as 1.560, the kinetic equation is dα/dt=3.062×1036exp(-30554.166/T)(1-α)1.560

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Stolarek, Paweł, Stanisław Ledakowicz, and Radosław Ślęzak. "Influence of Liming on Kinetics of Sewage Sludge Pyrolysis." Ecological Chemistry and Engineering S 26, no. 1 (March 1, 2019): 175–88. http://dx.doi.org/10.1515/eces-2019-0013.

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Abstract Thermogravimetry (TG) is the fast and reliable method for characterization of thermal decomposition of any material and in particular to determine the kinetics of pyrolytic decomposition of sewage sludge. Two types of sewage sludge with and without addition of lime were investigated from kinetic point of view. For TG analysis samples of selected sewage sludge were heated under the inert atmosphere of argon with constant heating rate from 303 to 1273 K; the three heating rate β = 5, 10 and 20 K/min were chosen. The iso-conversion methods of Friedman and Ozawa-Flynn-Wall were employed for analysis of TG results. As the sewage sludge decomposition is very complex process it cannot be described by a simple stoichiometric equation, therefore the so called lumping of reactions in the selected temperature ranges were used with detailed principles arising from visual analysis of DTG curve. The deconvolution of DTG curves performed according to Fraser-Suzuki asymmetric profile allowed the identification of number of lumps and their contribution to the overall mass loss. So the decomposition of sewage sludge with lime addition could be described with five groups of reactions while the one without lime by means of six lumps. The thermal decomposition of sewage sludge was assumed to proceed according to the scheme of parallel concurrent independent reactions of n-th order. The values of the apparent activation energies at different constant values of conversion degrees were determined by the iso-conversion analysis. To estimate the kinetic parameters the non-linear regression with Levenberg-Marquart optimization procedure was used. The kinetic parameters such as activation energy, pre-exponential factor, reaction order and fraction of total mass loss associated with a given reaction were determined. The impact of sewage sludge liming revealed in essential differences of pyrolysis products and pyrolysis kinetics of limed sludge and without lime one was highlighted.

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Abd El-Wahab, Mohamed M. M., and Mohamed A. Abd-Alla. "Arylidene Polymers—XXII. Thermogravimetric and Kinetic Analyses of Non-isothermal Decomposition of Organometallic Arylidene Polyester." High Performance Polymers 4, no. 4 (August 1992): 215–24. http://dx.doi.org/10.1088/0954-0083/4/4/002.

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Studies of non-isothermal decomposition of certain iodo-organometallic arylidene polyesters and organometallic arylidene polyesters have been performed with TGA measurements at atmospheric pressure. The analysis of the non-isothermal TG and DTG curves of the samples under investigation revealed that their decomposition course proceeds via three stages. The kinetic parameters such as activation energy (E,), preexponential factor (A) and entropy of activation (AS*) for all polymers at different decomposition stages are determinedfrom an appropriate kinetic equation. More particularly, the data showed that the thermal stability of some of the polymers decreases with increasing ring size of arylidene moieties. Furthermore, the effect of absence of iodoand presence of-OCH3 groups upon the thermal properties of polymers was also evaluated.

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Ahmad, Naushad, Manawwer Alam, Rizwan Wahab, Mukhtar Ahmed, and Ashfaq Ahmad. "Synthesis, spectral and thermo-kinetics explorations of Schiff-base derived metal complexes." Open Chemistry 18, no. 1 (October 20, 2020): 1304–15. http://dx.doi.org/10.1515/chem-2020-0168.

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AbstractSchiff-base ligand, 2,6-bis(benzimino)-4-phenyl-1,3,5-triazine (L), and its transition metal complexes of Co(ii), Ni(ii), and Cu(ii) were synthesized by refluxing the reaction mixture and its analytical, spectral, and thermogravimetric characteristics were explored by various techniques: AAS, FT-IR, UV-vis, TG-DTG, CHNS/O, and VSM. It was observed that all the metal containing complexes are non-electrolytic, mononuclear, and paramagnetic in nature, confirmed by the molar conductance and magnetic susceptibility measurements. Optical spectral data were used to investigate the geometrical and spectral parameters of [Co(L)(ac)2], [Ni(L)(ac)2], [Cu(L)(ac)2], [Cu(L)(acac)2], and [Cu(L)(fmc)2] complexes. Simultaneous thermal analyses (TG-DTG) in nitrogen atmosphere reveal that the ligand decomposes in one step, [Co(L)(ac)2], [Ni(L)(ac)2], and [Cu(L) (ac)2] complexes are decomposed in three steps, whereas [Cu(L)(acac)2] and [Cu(L) (fmc)2] are decomposed in five and two steps, respectively. In addition, activation energy (Ea) and pre-exponential factor (ln A) were evaluated by TG-DTG decomposition steps of compounds using the Coats–Redfern formula. Enthalpy (∆H), entropy (∆S), and Gibbs free energy (∆G) of the as-prepared metal complexes were also speculated by various thermodynamic equations.

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Liu, Yan-Hong, Tong-Lai Zhang, Jian-Guo Zhang, Li Yang, Jin-Yu Guo, Wei Yu, Rui-Feng Wu, and Kai-Bei Yu. "Synthesis, characterization, and the molecular structures of two new kinds of stilbene." Canadian Journal of Chemistry 84, no. 6 (June 1, 2006): 867–73. http://dx.doi.org/10.1139/v06-083.

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We report in this study the synthesis, crystal culture, and single-crystal X-ray crystallography of two new kinds of double stilbene, which were readily prepared from trinitro-p-xylene and p-tolualdehyde in the presence of piperidine. We found that these triclinic crystals belong to the space group P-1. These compounds were also investigated using FT-IR, 1H NMR, 13C NMR, and MS spectroscopy techniques. The thermal decomposition processes of the compounds were tested by DSC and TG-DTG at a heating rate of 10 C/min. These results indicate that the compounds have high heat-resistant stability.Key words: polynitrostilbene, molecular structure, thermal decomposition.

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Daneluti, André Luis Máximo, and Jivaldo do Rosário Matos. "Study of thermal behavior of phytic acid." Brazilian Journal of Pharmaceutical Sciences 49, no. 2 (June 2013): 275–83. http://dx.doi.org/10.1590/s1984-82502013000200009.

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Phytic acid is a natural compound widely used as depigmenting agent in galenic cosmetic emulsions. However, we have observed experimentally that phytic acid, when heated to 150 ºC for around one hour, shows evidence of thermal decomposition. Few studies investigating this substance alone with regard to its stability are available in the literature. This fact prompted the present study to characterize this species and its thermal behavior using thermal analysis (TG/DTG and DSC) and to associate the results of these techniques with those obtained by elemental analysis (EA) and absorption spectroscopy in the infrared region. The TG/DTG and DSC curves allowed evaluation of the thermal behavior of the sample of phytic acid and enabled use of the non-isothermal thermogravimetric method to study the kinetics of the three main mass-loss events: dehydration I, dehydration II and thermal decomposition. The combination of infrared absorption spectroscopy and elemental analysis techniques allowed evaluation of the intermediate products of the thermal decomposition of phytic acid. The infrared spectra of samples taken during the heating process revealed a reduction in the intensity of the absorption band related to O-H stretching as a result of the dehydration process. Furthermore, elemental analysis results showed an increase in the carbon content and a decrease in the hydrogen content at temperatures of 95, 150, 263 and 380 °C. Visually, darkening of the material was observed at 150 °C, indicating that the thermal decomposition of the material started at this temperature. At a temperature of 380 °C, thermal decomposition progressed, leading to a decrease in carbon and hydrogen. The results of thermogravimetry coupled with those of elemental analysis allow us to conclude that there was agreement between the percentages of phytic acid found in aqueous solution. The kinetic study by the non-isothermal thermogravimetric method showed that the dehydration process occurred in two stages. Dehydration step I promoted a process of vaporization of water (reaction order of zero), whereas dehydration step II showed an order of reaction equal to five. This change in reaction order was attributed to loss of chemically bonded water molecules of phytic acid or to the presence of volatile substances. Finally, the thermal decomposition step revealed an order of reaction equal to one. It was not possible to perform the kinetic study for other stages of mass loss.

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Yao, Run Sheng, Xu Wu, Ya Li Du, Xian Mei Xie, and Zhi Zhong Wang. "Study on the Thermal Decomposition Behavior of MgAl-Hydrotalcite Compounds." Advanced Materials Research 152-153 (October 2010): 1451–56. http://dx.doi.org/10.4028/www.scientific.net/amr.152-153.1451.

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MgAl-hydrotalcite compounds (MgAl-HT) with different n(Mg)/n(Al) ratios were synthesized by coprecipitation method. XRD and FT-IR were performed to characterize the structure of MgAl-HT. TG-DTG technology was adopted to study the thermal decomposition behavior. It was discovered that the thermal decomposition proceeded in two stages when the ratios of n(Mg) toward n(Al) being to 2~4. The kinetic parameters of the thermal decomposition procedure were also calculated by Ozawa method, which demonstrated that the value of active energy showed dynamic distribution. At each step of the decomposition behavior, the value of active energy decreased at first and then rose. The value of active energy for the deformation of the water in the interlayer was located within 45~90 kJ•mol-1 and within 150~230 kJ•mol-1 for the deformation of structure hydroxyl. Those characteristics were discussed and explained according to relative theory.

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Zhang, Hansong, Zhide Hu, Hujun Zhao, Dawei Wang, and Yulong Lei. "Influences of Saponification Time on the Physical Properties of Mineral Oil-Based Magnetorheological Grease." Journal of Physics: Conference Series 2174, no. 1 (January 1, 2022): 012020. http://dx.doi.org/10.1088/1742-6596/2174/1/012020.

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Abstract This study was conducted to investigate the influences of saponification time on the physical properties of mineral oil-based magnetorheological greases(MRGs). Three types of mineral oil-based MRG were prepared by applying different saponification time in this work. Then the physical properties, thermal stability and colloidal performance were tested. Besides, the micro-morphology was observed to analyze the microstructures of MRGs. The experimental results prove the formation of entanglement soap fibers micro-network. The oil separation on pressure and worked penetration of MRG decrease with the increase of saponification time, while the centrifugal stability becomes better. DSC-TG-DTG tests exhibit three endothermic peaks and reveal a double-stage thermal decomposition process. It also indicates that the MRG under 2 hours saponification has the smallest thermal decomposition and highest decomposition temperature, which demonstrates a good thermal stability.

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Journal articles on the topic 'Thermal decomposition (TG, DTG, SDTA)'

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