The Korean Society of Surface Science and Engineering

This study examines how surface modification treatments affect the surface energy of a polymer substrate and how these changes influence the adhesion strength of metal coatings. Polymethyl methacrylate (PMMA) was chosen as the substrate material. The surface of the PMMA was modified using atmospheric plasma treatment and fluorination coating. The surface energy was measured by evaluating the contact angle. After modification, a titanium (Ti) thin film was deposited on the substrate by sputtering, and the adhesion strength between the Ti coating and PMMA was measured using a Cross-cut test. The plasma treatment significantly increased the polar component of the surface energy, improving its interaction with the Ti coating. In contrast, the hydrophobic fluorination coating reduced the surface energy of the PMMA from 50.0 mJ/m^² to 38.2 mJ/m^². Importantly, the adhesion strength of the Ti coating showed a clear correlation with the surface energy of the substrate.

Keywords Surface modification; Adhesion; Surface energy; Contact angle; Polymer