Chen HX, Liu NA, Fan WC (2006a) A new method to explain the model dependence of apparent activation energy derived from a single nonisothermal dynamic curve. Polymer Degradation and Stability 91(8), 1726-1730. [In English]

Web link:http://dx.doi.org/10.1016/j.polymdegradstab.2005.12.007

Keywords:

model dependence; activation energy; model fitting; peak properly method; kinetic-parameters; thermogravimetric data; methodological problems; thermal-decomposition; dtg curves; degradation; mechanism; solids; polyethylene; temperature

Abstract: A single nonisothermal dynamic curve can be relatively correctly described by several reaction models in model-fitting approach, which yields model-dependent kinetic parameters. The model dependence of the apparent activation energy is explained mathematically by a new method which is developed from the peak property method in this paper. It has been found that the apparent activation energy rises linearly with the increase of the order of nth-order and Avrami-Erofeev reaction models, which can be verified by data from the literature and can explain some phenomena appeared in some articles. Moreover, the apparent activation energies derived from fitting a single nonisothermal dynamic curve to nth-order and Avrami-Erofeev reaction models can be correlated through the activation energy of 1st-order model. (c) 2005 Elsevier Ltd. All rights reserved.