Surface modification of insulating polymers by using APGD and DBD in air

Since the last decade, the atmospheric pressure glow discharge (APGD) and dielectric barrier discharge (DBD) has utilized for numerous applications. An experimental setup is constructed for generating the APGD or DBD. When inserting a mesh wire between the electrode and barrier, APGD can be generated as the form of DBD. The discharge mechanisms of APGD and DBD are discussed, and their characteristics are investigated and compared by measuring the electrical parameters and optical emission. The APGD and DBD are also employed to modify the surface of insulating materials. The material, the thickness of dielectric barriers and the style of the mesh wires have great influences on the discharge characteristics. While the gap distance is 1-2 mm, using the polyester or polytetrafluo- rethylene (PTFE) with the thickness from 0.08 mm to 0.1 mm and 325# mesh wires, it seems easy to generate homogeneous and stable APGD. The effects of APGD and DBD on the surface of PTFE are studied by the contact angle of water.