A study on the aging process of polystyrene thin films treated under DC pulsed discharges conditions in oxygen and argon-oxygen mixtures

¹ Laboratoire d'Électronique, des Gaz et des Plasmas, Université de Pau, 64000 Pau, France
² Laboratoire de Chimie Théorique et Physico-Chimie Moléculaire, UMR (CNRS) 5624, UFR Sciences, BP 1155, 64013 Pau Cedex, France

Corresponding author: bernard.held@univ-pau.fr

Received: 31 January 2002
Revised: 10 September 2002
Accepted: 12 September 2002
Published online: 19 November 2002

Abstract

This paper is devoted to polystyrene thin films treatment under DC pulsed discharges in oxygen-argon mixtures. AFM analysis is used to study the surface modifications in terms of morphology and corrugation. The use of a glow post-discharge enables to disregard the degradation process in relation to the functionalization process. Thus the increase of the polystyrene wettability is mainly due to the formation of polar functions which are of great interest to a better understanding of the treatment aging. Indeed, the reorganization of the macromolecular chains after a plasma treatment enables to obtain an equilibrium state of the surface in relation to the outer environment. Polar functions orient themselves toward the polymer bulk and may interact with another one to form hydrogen bonds, which establish physical linkages within the surface and its stabilization.