Optimization of Polyethersulfone Surface Properties Using Plasma Treatment Generated by Diffuse Coplanar Surface Barrier Discharge

ABSTRACT Surface modification is vital for naturally hydrophobic polymers like Polyethersulfone (PES) to enhance the wettability for specific applications. This study investigates the surface treatment of PES foil using a diffuse coplanar surface barrier discharge (DCSBD) plasma system in oxygen and nitrogen atmospheres. Plasma exposure significantly reduces water contact angle values, achieving saturation within 2 s, thus improving hydrophilicity. X‐ray photoelectron spectroscopy indicates increased oxygen‐containing functional groups, driving enhanced wettability. Atomic force microscopy and scanning electron microscopy reveal morphological changes, particularly low‐molecular‐weight oxidized material (LMWOM) formation after extended treatment and surface roughening. UV‐visible spectroscopy confirms minimal impact on optical transparency. This research highlights atmospheric‐pressure plasma treatment as a rapid, eco‐friendly approach for tailoring polymer surface properties.