The adsorption and curing behaviors of the epoxy/amidoamine system in the presence of metal oxides

The curing and adsorption behaviors of an epoxy/amidoamine system under the influence of iron, aluminum, and zinc oxides are studied by using differential scanning calorimetry (DSC) and diffuse reflectance infrared spectroscopy (DRIFT). From DRIFT, it is obtained that the amidoamine curing agent is preferentially adsorbed on the three metal oxide surfaces. The amount of amidoamine adsorbed is in the order of iron oxide > zinc oxide > aluminum oxide. Moreover, the iron and zinc oxides adsorb resins more firmly than the aluminum oxide. The results of DSC analyses indicate that more amine related exotherms are found in the specimen filled with the iron oxide but more amide related exotherms are found in the zinc oxide added specimens and they are related to the difference in the preferential adsorption found on three metal oxides. The curing characteristics are also changed in the presence of metallic fillers and the greatest change is obtained from the specimen containing the iron oxide.