Study of the Plasma Treated Polymers and the Stability of the Surface Properties

摘要

The plasma technique is a dry process which can tailor polymers in order to improve their surface energy, optical reflection, permeability, surface conductivity, biocompatibility and adhesion to other materials, -(1-3). The most important feature of the plasma techniques is that the surface properties of the treated material can be modified without changing their intrinsic bulk properties. It is well known that plasma treatments can simultaneously bring about many changes on the surface of polymers, such as degradation of polymer chain, formation of free radicals, chemeical functionalization, etching and crosslinking (4,5). Usually, for applications such as improvement of the adhesion of polymers to metals for example, whic his mainly discussed in this paper, polar functional groups are introduced at the surface. However, the surface treatment of polymers in the aim to improve the macroscopic properties suc as adhesion requires a thorough understanding of the interfacial phenomena. That is why is this paper the surface modifications of plasma-modified polymers willl be discussed in terms of the modern theory of Lewis acid-base (electron donor-acceptor) interactions. The acid-base properties of polyaliphatic polymers such as PolyPropylene (PP) and High Density PolyEthylene (HDPE) treated in both an oxidizing atmosphere such as oxygen as well as a reducing atmosphere like ammonia will be discussed.