Abstract

An atmospheric argon plasma jet has been used to explore the plasma penetration inside tubes of small diameter and the plasma treatment effect on the inner tube surface. The goal of this paper is to show how the tube size can influence the plasma jet penetration and the resulting surface effects on polyethylene tubes with diameters varying between 0.28 mm and 3.00 mm. Optical emission spectroscopy and light emission images have been used to investigate the distribution of active species along the tube length. To examine the plasma treatment effect on the inner tube surface, capillary action, water contact angle measurements and XPS analysis have been used. The results presented in this paper will clearly demonstrate the great potential of atmospheric pressure plasma jets for inner tube surface modification.