Freeman-Carroll

Direct application of the differential equation is perhaps the simplest method of obtaining kinetic parameters from non-isothermal observations. However, the Freeman—Carroll difference—differential method [531] has proved reasonably easy to apply and the treatment has been expanded to cover all functions f(a). The methods are discussed in a sequence similar to that used in Sect. 6.2. 

The following is a description of the Freeman-Carroll method applied to DTA data. Consider the following DTA peak in which AT is plotted vs time, t, a representation of which given as follows ... 

Of course, it is of great interest to determine the kinetic parameters from the torque-temperature curves obtained with the MDR run in scanning mode. These parameters can be calculated from the curves shown in Figure 3.18 by using either the method based on Equation 3.11, called the Freeman-Carroll method, or the simple method based on fitting the parameters in Equation 3.19. 

The Freeman-Carroll method [21] is very well known, but tedious to use. The method based on fitting the parameters in Equation 3.19 is a method of least squares linear or nonlinear. It is very simple when the order of the overall cure reaction can be considered to be one. 

In order to estimate both E and n, the following Freeman-Carroll relationship can be applied, using data obtained from a single dynamic E)SC curve of resin curing (24) ... 

Analysis ol Decomposition Step I Using the Freeman - Carroll Metiod [see E(j,(8), Fig, 2.9... 

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