Thermal degradation modeling description

Figure 3.24 provides an example of such a plot for the thermal degradation of PEN at 420 °C. A first-order reaction model [Eq. (3.13)] has been found to lit the experimental data better than reaction order models of other n values. Although the g(a)-t plot is characterized by a reasonable correlation coefficient (r = 0.97), it demonstrates obvious systematic deviations from the straight line. The reason is that actual degradation processes tend to be more complex than the simplistic models widely used for their description. The rate constant k(T), obtained from the slope of the g(a) versus t, is 0.00133 s The value of k J can then be used to simulate the experimental a-t data by solving Eq. (3.11) with respect to a. For a first-order reaction model [Eq. (3.13)], the solution is given by... 

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