Atmospheric-pressure dielectric barrier discharge in He and He+O2 for surface modification of polymers

This paper provides an analysis on the various plasma effects on polymers exposed to atmospheric-pressure DBD. Homogeneous diffuse DBD, in symmetrical electrode configuration, working in He and He+O2 is used. The discharge is characterized by electric parameters measurement, whereas the surface is analyzed using contact angle measurement and XPS. The surface modification depends on the level of oxidation achievable, which is limited by the competition between functionalization and ablation, and by the intrinsic oxygen content of the polymer. The effect of oxygen due to residual air, inherently present in discharges at atmospheric pressure, on the surface modification, is demonstrated.