Surface characterization of plasma‐modified polyethylene by contact angle experiments and ATR‐FTIR spectroscopy

Abstract

Polymers such as polyethylene (PE) have a low surface free energy and therefore often require a modification of their surface properties before any use. Nonthermal plasma treatment is a convenient and environmentally friendly way to obtain these modifications by introducing new chemical groups at the surface without affecting the bulk properties. Therefore, in this article, a PE film is treated with a dielectric barrier discharge (DBD) operating in air at medium pressure (5.0 kPa). The surface properties of the plasma-treated PE films are characterized using contact angle measurements, surface free energy calculations and ATR-FTIR spectroscopy. The polymer films show a remarkable increase in surface free energy after plasma treatment. ATR-FTIR spectroscopy of the plasma-treated PE films reveals that plasma treatment introduces oxygen-containing functionalities, such as ketones, aldehydes, alcohols and carboxylic acids on the PE surface leading to the increased surface free energy. Copyright

Improving mechanical performance of thermoplastic adhesion joints by atmospheric plasma

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