EFFECT OF PLASMA TREATMENT ON SURFACE ENERGY AND RESISTIVITY OF POLYMERS

Abstract

Polymers have become important materials in the modern manufacturing processes and offer a wide variety of chemical and mechanical properties applicable to numerous problems. From structural to plastic compatibly with biological tissues, the uses of polymeric species continue to grow. Despite the versatility of many polymeric materials, there are limitations to many applications. Often, the surface properties of the polymer will preclude its use in an application to which its mechanical properties may be very well suited. Polymer surface modification can offer significant benefits by allowing the surface properties to be tailored to meet a specific requirement while retaining beneficial mechanical properties. Surface treatment of polymers is important to adhesion improvement and retention of mechanical properties upon environmental exposure. Chemical and physical treatments, in the form of traditional wet chemical methods or more frequently in the form of a gas phase treatment, can render polymers more compatible with standard adhesives and improve the adhesion of deposited films. Implantation of chemical functional groups, cross liking, thin film deposition, and chain scission can promote chemical compatibility of a polymer surface to an over layer. Gas phase treatments offer numerous advantages for polymer surface modification processes. Plasma lends itself well to production scale processes and provides good uniformity of surface treatment. The modification, either cross-linking, functional group attachment, or ablation, can be surface specific, leaving the bulk polymer and mechanical properties unaffected. A wide variety of plasma treatments such as corona, DC, RF and MW discharge treatment can be used to alter the chemical and physical surface properties. The present investigation has been carried out to see the effect of DC glow discharge treatment on a thin film of polypropylene. The effect of DC glow discharge on polypropylene film has been seen at various power levels with variation in exposure time. It has been found that the contact angle decreases and hence the total surface energy increases. It has also been found that for the comparable exposure time, the reduction in .........