Transferred plasma jet from a dielectric barrier discharge for processing of poly(dimethylsiloxane) surfaces

TL;DR

This study compares dielectric barrier discharge plasma treatments, including a transferred plasma jet, on PDMS surfaces, revealing higher vibrational temperatures and improved surface wettability and adhesion with the transferred jet.

Contribution

It introduces the use of a transferred plasma jet in DBD plasma treatment of PDMS and links higher vibrational temperature to enhanced surface properties.

Findings

Transferred plasma jet has higher vibrational temperature than primary jet.

Higher vibrational temperature correlates with improved surface wettability.

Surface roughness changes are observed after plasma treatments.

Abstract

In this work we studied processing of poly(dimethylsiloxane) (PDMS) surfaces using dielectric barrier discharge (DBD) plasma in two different assemblies, one using the primary plasma jet obtained from a conventional DBD and the other using a DBD plasma jet transfer. The evolution of water contact angle (WCA) in function of plasma processing time and in function of aging time as well as the changes in the surface roughness of PDMS samples for both plasma treatments have been studied. We also compared vibrational and rotational temperatures for both plasmas and for the first time the vibrational temperature (T_vib) for the transferred plasma jet has been shown to be higher as compared with the primary jet. The increment in the T_vib value seems to be the main reason for the improvements in adhesion properties and surface wettability for the transferred plasma jet. Possible explanations for the increase in the vibrational temperature are presented.