Reflection-Absorption Infrared Spectroscopy and Ellipsometry of Epoxy Films on Metals

Abstract

Reflection-absorption infrared spectroscopy and ellipsometry have been used to determine the structure of films formed by an epoxy resin adsorbed from solution onto polished iron and copper mirrors. Films only about 15 Å thick were obtained. The infrared spectra of these films were characterized by absorption bands near 1500 and 1240 cm⁻¹. Consideration of the thickness of the adsorbed films as well as wetability, surface coverage, and the relative intensities of the bands near 1500 and 1240 cm⁻¹ indicates that the epoxy resin molecules are probably adsorbed with a vertical conformation where only a single oxirane oxygen atom is in contact with the surface.