X-ray photoelectron spectroscopy studies of plasma-modified PET surface and alumina/PET interface

X-ray photoelectron spectroscopy was used to study the chemical effects of a reactive plasma treatment on the PET surface and to investigate the chemical interactions involved at the alumina/PET interface. The treatment of the PET by a carbon dooxide plasma introduces new oxygen reactive species on the polymer surface. Evidence of this chemical modification is given by the appearance of additional carbonyl bonds. The interfacial study reveals a reaction of alumina with the oxygen atoms of the carbonyl bonds of PET (plasma-induced carbonyl bonds and carbonyl bonds of the ester groups). This chemical interaction results in the formation of AlOC interfacial bonds in the early stages of deposition.