The role of wire-mesh electrodes on the mode transition of dielectric barrier discharge and its effects on the surface wettability of polycaprolactone

Atmospheric pressure dielectric barrier discharge is established to optimize discharge conditions, transitioning from filamentary mode to a stable discharge appearance. The uniform discharge, characterized by numerous beneficial properties, is advantageous for the modification of material surfaces. To generate the discharge, disc electrodes are linked to a variable high-power supply capable of delivering up to 42 kV at 50 Hz. Oxygen gas is introduced into the reactor at a consistent flow rate of 70 ml/min, with discharge gaps ranging from 1 to 4 mm. Two glass dielectrics, wire-meshes and Polyethylene Terephthalate films were utilized to cover both electrodes. The results indicate that filamentary discharge at 27 kV advances into a uniform discharge under atmospheric pressure. When Polycaprolactone was subjected to optimal discharge conditions, contact angle measurements showed a reduction as discharge time increased.