Discharge characteristics of DBD tube electrode array and its modification for PET films

Polymers films are commonly used in industry for packaging applications, machinery manufacturing and power electronics industries. To further improves its application field, surface modification is usually necessary to improve wettability, printability and adhesive properties. Most of the existing atmospheric pressure low temperature plasma reactors range in size from a few to tens of centimeters and work under intermittent operation, which can't meet the need for industrial continuous processing. In this paper, an atmospheric dielectric barrier discharge (DBD) for large-scale processing was designed, which was applied to treat polyethylene glycol terephthalate (PET) film. The discharge characteristics under different electrode structure parameters and the physicochemical properties of the PET surface before and after modification were investigated. The results show that the increase in the electrode gap leads to more intense and diffuse discharge with stronger luminous intensity. The decrease in processing speed and the increase in voltage amplitude both enhance the surface hydrophilicity. The increased surface roughness and introduction of active groups on PET surface after plasma treatment improve the hydrophilicity of the material surface.