Surface modification by low-pressure glow discharge plasma of an unsaturated polyester resin:: effect on water diffusivity and permeability

Unsaturated polyester resin (UPR) films have been modified by a tetrafluoromethane microwave plasma. The treated surface morphologies investigated by contact angle, atomic force microscopy and permeation measurements show that the CF, plasma treatment decreases drastically the surface energy by increasing the hydrophobic character. The surface modification due to plasma fluorination decreases the water content diffusing through the UPR film and the time lag diffusion coefficient and thus, the sorption kinetic. From these results, it is clearly shown that the CF, plasma treated layer improves drastically the barrier effects. (C) 1999 Elsevier Science S.A. All rights reserved.