Investigations of the interface between magnesium and polyethyleneterephthalate by X-ray photoelectron spectroscopy

The interfacial chemistry between in-situ thermally evaporated magnesium and a polyethyleneterephthalate (PET) film is studied by X-ray photoelectron spectroscopy (XPS). The initially deposited Mg atoms adsorb on the PET surface, via an addition reaction to the CO groups, with the simultaneous formation of MgO and MgC bonds. Further metallization shows condensation in the agglomeration mode, with metallic clusters formed by adsorption on to the initial Mg at the PET interface. With exposure of the Mg/PET film to air, the interface does not change although the outer metallic component oxidizes. Rinsing this air-oxidized Mg/PET film with water removes all the magnesium and leaves a modified PET surface compared with its initial state.