Iterative method to improve calculation of the pre-exponential factor for dynamic thermogravimetric analysis measurements

作者：Gao ZM^*; Wang HX; Nakada M

来源：Polymer, 2006, 47(5): 1590-1596.

DOI：10.1016/j.polymer.2006.01.053

• iterative method
• pre-exponential factor
• isoconversional plot

The conventional isoconversional plot of ln(beta/T-2) versus 1/T usually has a large error of about - 10% in calculation of the pre-exponential factor as a consequence of assuming h(x) = 1. Iterative calculation using the plot of ln(beta/hT(2)) versus 1/T is thus suggested. It is illustrated that the iterative method can greatly improve calculation for the pre-exponential factor. Success in calculation for the pre-exponential factor is accompanied by an enhanced accuracy in value of activation energy given by the iterative method in comparison with the conventional isoconversional plot of ln(beta/T-2) versus 1/T. One explanation is due to the compensation effect of the Arrhenius parameters. The iterative method has been applied to thermal degradation reactions of poly(methyl methacrylate) (PMMA) and polyethylene.

• 出版日期2006-2-22
• 单位北京理工大学