Photoprotective ceramic coatings on poly(ether ether ketone)

Zinc oxide and titanium dioxide coatings were deposited on poly(ether ether ketone) (PEEK) films by r.f. magnetron sputtering from ceramic targets in different argon–oxygen mixtures. PEEK and ceramic/polymer assemblies were irradiated with polychromatic light (λ>300 nm). The structure modifications of the surface of irradiated PEEK films were studied by X-ray photoelectron and the rate of photoproducts formation was measured by infra-red and UV–visible spectroscopies. The ZnO coatings were found to protect more efficiently PEEK than TiO2 coatings. The photoprotective efficiency was shown to depend on the thickness and structural properties of the ceramic coating. The sputtering parameters (total pressure, plasma composition, r.f. power) were optimised in order to limit the photodegradation of the polymer.