Kinetic investigation of eggshell powders as biobased epoxy catalyzer

Epoxy resins from bisphenol A of diglycidyl ether/anhydride methyl tetrahydrophthalic/2,4,6-tris dimethylaminomethyl phenol were prepared by mechanical mixing using a magnetic stirrer. Substitution of synthetic catalyzer by eggshell powders provided high performance biobased materials. Chemical character analysis of epoxy/eggshell carried out using dispersive energy spectrometry, and Fourier transform infrared spectroscopy, acquired data indicated the eggshell membrane as a suitable catalyzer for the cross-linking reaction, due to the presence of amines, hydroxyl and sulfur that could participate in the cross-link reaction. The cure kinetics was investigated using differential scanning calorimetry and applying Ozawa, Kissinger, Friedman isoconversional, Malek, and Friedman model-based, where Malek and Friedman model-based presented the best fits to describe synthetic and biobased materials.