Electrohydraulic Discharge Detackifies Polymer Surfaces in Water

Firing a high-energy spark underwater creates a plasma channel, which is partially dissipated through an acoustic field. Films of polyacrylate adhesive and wood pitch on metal coupons placed in this field are efficiently detackified. Tack reduction can also be induced through ultrasonic treatment, but at lower efficiency. The spark-generated acoustic field creates a high concentration of hydroxyl radicals at a range of over 1.5 m, which makes it suitable for industrial applications. The zeta potential of acrylate particles suspended in water and the surface pH of acrylate films both decrease upon exposure, indicating the creation of surface acidic groups.