Abstract
The application of the average linear integral isoconversional method developed by Ortega for evaluating the activation energies of solid state reactions may be hindered by experimental noise and the uncertainties associated with selecting appropriate reaction segments. This paper suggests a procedure, called the modified Ortega method, which can avoid or minimize these hindrances. By applying the modified Ortega method to the kinetic analyses of both simulated and experimental data, a more consistent dependence of the activation energy on the extent of reaction conversion was found with those calculated from the modified Vyazovkin method and the Friedman method.
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References
Coats AW, Redfern JP. Kinetic parameters from thermogravimetric data. Nature. 1964;201(4914):68–9.
Vyazovkin S, Wight CA. Kinetics in solids. Annu Rev Phys Chem. 1997;48:125–49.
Vyazovkin S. Modification of the integral isoconversional method to account for variation in the activation energy. J Comput Chem. 2001;22(2):178–83.
Budrugeac P. Differential non-linear isoconversional procedure for evaluating the activation energy of non-isothermal reactions. J Therm Anal Calorim. 2002;68(1):131–9.
Wanjun T, Donghua C. An integral method to determine variation in activation energy with extent of conversion. Thermochim Acta. 2005;433(1–2):72–6.
Han Y, Chen H, Liu N. New incremental isoconversional method for kinetic analysis of solid thermal decomposition. J Therm Anal Calorim. 2011;104(2):679–83.
Ortega A. A simple and precise linear integral method for isoconversional data. Thermochim Acta. 2008;474(1–2):81–6.
Friedman H. Kinetics of thermal degradation of char-forming plastics from thermogravimetry-application to a phenolic resin. J Polym Sci Part C. 1964;6:183–95.
Ozawa T. A new method of analyzing thermogravimetric data. Bull Chem Soc Jpn. 1965;38(11):1881–6.
Vyazovkin S. Evaluation of activation energy of thermally stimulated solid-state reactions under arbitrary variation of temperature. J Comput Chem. 1997;18(3):393–402.
Li C-R, Tang TB. A new method for analysing non-isothermal thermoanalytical data from solid-state reactions. Thermochim Acta. 1999;325(1):43–6.
Flynn JH, Wall LA. A quick, direct method for the determination of activation energy from thermogravimetric data. J Polym Sci Part C. 1966;4(5):323–8.
Mothé M, Leite L, Mothé C. Kinetic parameters of different asphalt binders by thermal analysis. J Therm Anal Calorim. 2011;106(3):679–84.
Suñol J, Bonastre J. Crystallization kinetics of metallic glasses. J Therm Anal Calorim. 2010;102(2):447–50.
Wang H-M, et al. Synthesis and curing behavior of a novel liquid crystalline epoxy resin. J Therm Anal Calorim. 2011;103(3):1031–7.
Vyazovkin S. Two types of uncertainty in the values of activation energy. J Therm Anal Calorim. 2001;64(2):829–35.
Criado J, Sánchez-Jiménez P, Pérez-Maqueda L. Critical study of the isoconversional methods of kinetic analysis. J Therm Anal Calorim. 2008;92(1):199–203.
Acknowledgements
This study was supported as part of Revstone-IR4TD research partnership project under the technical monitoring of Mr. Scott Hofmeister. Many thanks to Dr. John Stencel for his valuable comments and discussions.
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Han, Y., Li, T. & Saito, K. A modified Ortega method to evaluate the activation energies of solid state reactions. J Therm Anal Calorim 112, 683–687 (2013). https://doi.org/10.1007/s10973-012-2591-0
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DOI: https://doi.org/10.1007/s10973-012-2591-0