Experimental Study of an Atmospheric Pressure Dielectric Barrier Discharge and PET Surface Modification

A homogeneous dielectric barrier discharge (DBD) in argon was produced by applying high voltage A.C. source of potential difference (0-20) kV operating at a frequency of 10-30 kHz across two parallel plate electrodes with glass as dielectric barrier. The discharge was characterized by optical emission spectroscopy (OES) and electrical measurement. Four argon emission lines from the discharge were analyzed and the electron temperature was estimated by line intensity ratio method. The electron density in the discharge was estimated by power balance method. An investigation of the effect of inter-electrode distance on the electron density was made. The results showed that the electron temperature is less than 1 eV and the electron density is of the order of 10 11 cm -3 which varied with the inter electrode distance. Discharge was applied for surface modification of polyethylene terepthalate (PET). Modified surfaces were studied by contact angle measurement and FTIR spectroscopy.