DBD plasma improved spot repair of automotive polymer surfaces

Plasma activation effects on automotive polymers by low temperature plasma at atmospheric pressure have been studied. The aim of this work was the improvement of the polymer surface polarity in order to replace the use of adhesive layers before application of lacquering. Two different concepts of dielectric barrier discharge, direct and indirect plasma treatment, were applied. The efficiency of such plasma treatment was determined by adhesive pull strength tests and surface energy calculations. It was shown that both plasma treatment methods allow a significant increase in surface polarity up to a factor of 20 and adhesive pull strength of lacquers up to a factor of 29 respectively. In comparison to indirect surface treatment, the direct treatment features a higher efficiency in terms of increasing both, polarity and adhesive pull strength.