Curing kinetics of solid epoxy/DDM/nanoclay: Isoconversional models versus fitting model

• The curing behavior and kinetics of a solid epoxy/DDM/clay nanocomposite system were studied.
• The effect of clay surface modification on the curing of solid epoxy/DDM was investigated.
• Curing behavior and kinetics were studied using DSC and evaluated by fitting model and isoconversional models.
• The superiority of isoconversional models for elaborating of the effect of nanoparticles on the curing mechanism of epoxy/DDM/clay was demonstrated.

The curing behavior and kinetics of epoxy nanocomposites based on solid epoxy, diaminodiphenyl methane (DDM) and nano organoclay were studied. The curing kinetics of epoxy nanocomposites was elucidated by non-isothermal differential scanning calorimetry. The fitting model was used to calculate the kinetic parameters. The kinetics of the curing reaction was also evaluated by two different isoconversional models. The kinetic parameters calculated from fitting model were almost the same for neat epoxy system and nanocomposite systems indicating that the curing kinetics was not affected by the presence of nanoclay particles. However, the isoconversional models showed that the incorporation of nanoclay particles into the epoxy/DDM system had a significant effect on the trend of activation energy during the curing process. Therefore, it can be concluded that using isoconversional models would be a preferred method to elaborate the effect of nanoparticles on the curing mechanism of nanocomposite systems.