Activation of poly(methyl methacrylate) surfaces by atmospheric pressure plasma

The use of atmospheric plasma generated by Diffuse Coplanar Surface Barrier Discharge (DCSBD) for treatment of poly (methyl methacrylate) (PMMA) sheets is presented. The modified surfaces were characterized by contact angle measurements to determine the free surface energy, atomic force microscope (AFM) to investigate the changes in surface morphology, and X-ray photoelectron spectroscopy (XPS) to study the chemical composition changes after the plasma treatment. We found that increased free surface energy was related to the enhanced oxygen containing chemical groups on the polymer surface. In respect to the influence of gas composition, similar results were achieved from ambient air, nitrogen and oxygen. AFM measurements showed no effect on surface morphology by the plasma treatment. The stability of hydrophilic property was achieved over 3-5 days after plasma treatment.