SURFACE CHEMICAL STUDIES OF CORONA TREATED POLYMER SUBSTRATES

Njeri L. Lawrence and Dr. James P. Wightman
National Science Foundation and Technology Center:
High Performance Polymeric Adhesive and Composites, and
Department of Chemistry
Virginia Polytechnic Institute and State University
Blacksburg, Virginia

ABSTRACT

Low density polyethylene and polypropylene substrates were treated with corona discharges and aged to examine pretreatment effects. The initial and long-term chemical changes that occurred on the surface as a result of the pretreatment were investigated using x-ray photoelectron spectroscopy (XPS). A 180 deg. peel test with an acrylate-based pressure sensitive adhesive tape as an adherend was utilized to measure the peel strength of surfaces. Water and diidomethane contact angle analysis (CAA) were used to characterize the changes in surface wettability and estimate surface energy. Corona discharge treatment increases the polypropylene and low density polyethylene surface tensions, causing better adhesive bonding and surface wettability.