Polymer surface reactivity enhancement by ultraviolet ArF laser irradiation: An x-ray photoelectron spectroscopy study of polytetrafluoroethylene and polyethyleneterepthalate ultraviolet treated surfaces

Abstract

We have investigated by x-ray photoelectron spectroscopy (XPS) the surface of two polymers [polytetrafluoroethylene and polyethyleneterepthalate (PTFE) and (PET)] which were previously submitted to pulsed UV radiation delivered from an excimer laser (ArF: λ=193 nm). Treatments realized under different gaseous atmospheres allow us to point out mechanisms leading to several chemical transformations at the polymer surface. In the case of PTFE, the high-fluence irradiations produce defluorination with surface oxidation. The latter is mainly due to air moisture. The deposition of some ablated fragments on the surface has also been observed. For PET, the major modifications are produced below the ablation threshold. They are characterized by severe deoxidation due to the loss of CO and CO2. The irradiations under oxygen and nitrogen atmospheres show the possibility of grafting new functionalities at the polymer surface.