SURFACE-ANALYSIS OF CHEMICALLY-ETCHED AND PLASMA-TREATED POLYETHERETHERKETONE (PEEK) FOR BIOMEDICAL APPLICATIONS

Surface modifications of polyetheretherketone (PEEK) made by chemical etching or oxygen plasma treatment were examined in this study. Chemic al etching caused surface topography to become irregular with higher r oughness values R-a, and R-q,. Oxygen plasma treatment also affected s urface topography, unveiling the spherulitic structure of PEEK. R-a,, R-q, and surface area significantly increased after plasma treatment; topographical modifications were, nonetheless, moderate. Wetting angle measurements and surface energy calculations revealed an increase of wettability and surface polarity due to both treatments. XPS measureme nts showed an increase of surface oxygen concentration after both trea tments. An O:C ratio of 3.10 for the plasma-treated PEEK surface and 4 .41 for the chemically-etched surface were determined. The results ind icate that surface activation by oxygen plasma treatment for subsequen t coating processes in supersaturated physiological solutions to manuf acture PEEK for biomedical applications is preferable over the chemica l etching treatment. (C) 1997 Elsevier Science S.A.