APPLICATION OF X-RAY PHOTOELECTRON SPECTROSCOPY FOR CHARACTERIZATION OF PET BIOPOLYMER

X-ray photoelectron spectroscopy (XPS) is probably the most popular method for characterization of polymer surfaces. Although this technique is widely used, small details are often very important for proper evaluation of experimental results. Some details are addressed in this paper. First, the influence of surface roughness is examined and the results show substantial differences in high-resolution Cls spectra although the survey spectra remain fairly unaffected by the roughness. Second, the influence of the X-ray brilliance is studied for classical sources such as Mg K-a at 1253 eV, Al K-a at 1486 eV and Al K-a monochromized light. No substantial difference between the classical Mg and Al sources were found, while the high resolution spectra obtained using monochromatized light have a much better resolution. These details are very important in practical applications. Some examples including vascular grafts are shown in this paper.