PTFE treatment by remote atmospheric Ar/O2 plasmas: a simple reaction scheme model proposal

TL;DR

This paper investigates PTFE surface modifications using remote atmospheric Ar/O2 plasmas, correlating water contact angle changes with surface chemistry and proposing a simple reaction scheme to explain the observed effects.

Contribution

It introduces a simple kinetic model for PTFE surface reactions under plasma treatment, linking surface chemistry, roughness, and wettability changes.

Findings

Pure argon plasma decreases WCA, reducing hydrophobicity.

Adding oxygen increases hydrophobicity, enhancing surface water resistance.

WCA changes are linked to surface roughness and chemical modifications.

Abstract

Polytetrafluoroethylene (PTFE) samples were treated by a remote atmospheric pressure microwave plasma torch and analyzed by water contact angle (WCA) and X-ray photoelectron spectroscopy (XPS). In the case of pure argon plasma a decrease of WCA is observed meanwhile an increase of hydrophobicity was observed when some oxygen was added to the discharge. The WCA results are correlated to XPS of reference samples and the change of WCA are attributed to changes in roughness of the samples. A simple kinetics scheme for the chemistry on the PTFE surface is proposed to explain the results.