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Journal of Thermal Analysis and Calorimetry
Authors: J. Santos, M. Conceiçăo, M. Trindade, A. Araújo, V. Fernandes, and A. Souza

Abstract  

The lanthanidic complexes of general formula Ln(C11H19O2)3 were synthesized and characterized by elementary analysis, infrared absorption espectroscopy, thermogravimetry (TG) and differential scanning calorimetry (DSC). The reaction of thermal decomposition of complexes has been studied by non-isothermal and isothermal TG. The thermal decomposition reaction of complexes began in the solid phase for Tb(thd)3, Tm(thd)3 and Yb(thd)3 and in the liquid phase for Er(thd)3 and Lu(thd)3, as it was observed by TG/DTG/DSC superimposed curves. The kinetic model that best adjusted the experimental isothermal thermogravimetric data was the R1 model. Through the Ozawa method it was possible to find coherent results in the kinetic parameters and according to the activation energy the following stability order was obtained: Tb(thd)3>Lu(thd)3>Yb(thd)3>Tm(thd)3>Er(thd)3

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Abstract  

The thermal decomposition of ammonium perchlorate (AP)/hydroxyl-terminated-polybutadiene (HTPB), the AP/HTPB solid propellant, was studied at different heating rates in dynamic nitrogen atmosphere. The exothermic reaction kinetics was studied by differential scanning calorimetry (DSC) in non-isothermal conditions. The Arrhenius parameters were estimated according to the Ozawa method. The calculated activation energy was 134.5 kJ mol-1, the pre-exponential factor, A, was 2.04×1010 min-1 and the reaction order for the global composite decomposition was estimated in 0.7 by the kinetic Shimadzu software based on the Ozawa method. The Kissinger method for obtaining the activation energy value was also used for comparison. These results are discussed here.

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Journal of Thermal Analysis and Calorimetry
Authors: Nopsiri Chaiyo, Rangson Muanghlua, Surasak Niemcharoen, Banjong Boonchom, Panpailin Seeharaj, and Naratip Vittayakorn

-exponential factor, A , and the mechanism functions, f (α), of MgC 2 O 4 ·2H 2 O were obtained by analyzing the TG-DTG curves of their thermal decomposition using the Popescu and Flynn–Wall–Ozawa method [ 11 ]. Furthermore, the decomposed products, e.g., oxide or

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Abstract  

The urethane forming cure reactions of hydroxyl terminated polybutadiene (HTPB) binder with three different isocyanate curatives, viz., toluene diisocyanate (TDI), isophorone diisocyanate (IPDI) and 4,4'-methylene bis(cyclohexyl isocyanate) (MCHI), were investigated by differential scanning calorimetry (DSC). The effect of two cure catalysts, viz., dibutyl tin dilaurate (DBTDL) and ferrric tris-acetylacetonate (FeAA) on the cure reactions was also studied. Cure kinetics was evaluated using the multiple heating rate Ozawa method. The reactivities of the three isocyanates and catalytic efficiencies were compared based on the DSC reaction temperatures, activation energies and rate constants. Viscosity build-up in these systems at isothermal temperature was also studied and compared with the results from DSC.

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Journal of Thermal Analysis and Calorimetry
Authors: A. M. Ramalho, M. M. Conceiçăo, V. J. Fernandes Jr., J. C. Machado, L. E. B. Soledade, and A. G. Souza
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by plotting ln( β / T p 2 ) against 1,000/ T P . Flynn–Wall–Ozawa method [ 14 , 15 ] Separating the variable Eq. 6 , it could be obtained: 8 Defining x = E / RT and integrating the right-hand side

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regardless of the method used confirming the complex mechanism of the hematite crystallization process in the aventurine glaze. • The Avrami exponent values, calculated by Ozawa method, also confirm the

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average of three values. The conversion values 5, 8, 11, 14, 17, and 20% have been used to derive the E a using the Flynn–Wall–Ozawa method. Limited information can be obtained especially about the chemistry of the decomposition by TG

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activation energy as a function of transformed fraction is obtained by means of KAS and Friedman isoconversional methods. The variation of the growth exponent is obtained using Ozawa method. The following conclusions can be drawn: • The

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/ATH/Fe-OMT nanocomposites using different kinetic models including Kissinger, Friedman, and Flynn–Wall–Ozawa methods. The kinetic parameters obtained by the above different methods were then compared and meanwhile were connected with the flame-retardancy of the related

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