Title: Matlab-Based Combinatorial Isoconversional Analysis Techniques for Characterizing Thermoset Cure Kinetics

Authors: Adam Watts, Mark Peyron

DOI: 10.33599/nasampe/s.22.0808

Abstract: Isoconversional analysis (ICA) is one of the most important methods for establishing the kinetics of the complex reactions associated with curing thermosets. An often overlooked or hard to establish feature of these kinetics is estimating the uncertainties in the kinetic parameters. In the case of ICA, activation energy is measured at fixed values of reaction conversion. For thermosets the data are typically based on differential scanning calorimetry (DSC). When replicate DSC data are obtained there is no agreement how to utilize the replicates to assess repeatability in the context of ICA. The authors propose that a combinatorial approach be used to assess the variability due to i) experimental variability and ii) linear and nonlinear computations that are used to calculate values of the activation energy. A MATLAB-based analysis was developed to analyze all possible combinations of replicates and using four different ICA methods to establish a conversion map of activation energies along with statistically valid values of standard deviations. The use of these techniques is demonstrated with a benzoxazone resin. This combinatorial technique provides new insights into uncertainty associated with modeling thermoset cure kinetics. This technique may also be used to estimate the uncertainty in isothermal and nonisothermal predictions based on the DSC data and measured activation energies. The MATLAB analysis will be made freely available to other users via the author’s website. It may be applied to any thermally-stimulated process.

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Conference: SAMPE 2022

Publication Date: 2022/05/23

SKU: TP22-0000000808

Pages: 15

Price: $30.00