Reliability Evaluation of a New Method Developed for DSC Curing Kinetic Model of Epoxy Resin

The curing kinetic model of epoxy resin is crucial for understanding reaction mechanism and accurately describing curing behavior of fiber reinforced polymer composites. In the investigations related to kinetic models of epoxy, much attention is payed to the curing characterizations of modified or mixed materials for the desired field of application in the case that the initial curing degree for calculating kinetic parameters is generally constant. In this paper, a new method by specifying the initial curing degree for kinetic parameters is developed to improve the accuracy of fitting models based on the resin systems and methods for activation energy. The curing kinetics of resin systems including Epoxy 4330, Epoxy 5212, and diglycidyl ether pentaerythritol vanillin diacetal-bisphenol-A epoxy resin-4,4'-diaminodiphenyl sulfone (DEPVD-E51-DDS) are examined utilizing differential scanning calorimetric technique at five different heating rates. Additionally, Kissinger, Starink, and Friedman methods, and piecewise models are adopted to fit the experimental data. The predictions from fitting models using different initial curing degrees are subsequently compared with experimental data. It is concluded that the utilization of initial curing degree promotes the accuracy of fitting models.