Comparison Between Conventional and Transferred DBD Plasma Jets for Processing of PDMS Surfaces

This paper studies the 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 in the function of plasma processing time and in the function of aging time as well as the changes in the surface roughness of PDMS samples for both plasma treatments have been studied. The vibrational and rotational temperatures are compared for both plasmas and for the first time the vibrational temperature (Tvib) for the transferred plasma jet has been shown to be higher as compared with the primary jet. The increment in the Tvib 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.