Different configurations of transferred atmospheric pressure plasma jet and their application to polymer treatment

TL;DR

This study compares two atmospheric pressure plasma jet configurations with different transfer mechanisms, assessing their effectiveness in polymer surface treatment and potential applications in material and biological fields.

Contribution

It introduces and evaluates two novel APPJ configurations with different transfer methods, highlighting their distinct properties and suitability for specific applications.

Findings

Wire assembly plasma jet is more powerful with higher current and temperature.

Both configurations can introduce oxygen functional groups on polypropylene.

Wire configuration is better for material treatment; mesh is more suitable for biological applications.

Abstract

The employment of atmospheric pressure plasma jets (APPJs) in a large sort of applications is limited by the adversities related to the size of the treated area and the difficulty to reach the target. The use of devices that employ long tubes in their structure has contributed significantly to overcome these challenges. In this work, a comparison between two different plasma systems employing the jet transfer technique is presented. The main difference between the two devices is how the long plastic tube was assembled. The first one uses a copper wire placed inside a long plastic tube. The other device has a metallic mesh installed in a concentric arrangement between two coaxial plastic tubes. As a result, the two APPJ systems exhibit different properties, with the wire assembly being more powerful, also presenting higher values for the electrical current and rotational temperature when compared to the mesh mounting. X-ray photoelectron spectroscopy (XPS) demonstrates that both configurations were capable of inserting O-containing functional groups on the polypropylene (PP) surface. However, the transferred plasma jet with wire assembly was able to add more functional groups on the PP surface. The results from XPS analysis were corroborated with water contact angle measurements (WCA), being that lower WCA values were obtained when the PP surface presented higher amounts of O-containing groups. Surface morphology evaluation showed that the plasma treatment tends to slightly increase the surface roughness of the PP samples with both wire and mesh configurations. Furthermore, the findings in this work suggest that the APPJ with wire configuration is more appropriate for material treatments, while the transferred jet with mesh arrangement tends to present lower electrical current values which makes it more suitable for biological applications.