In this study, the effect of plasma treatment on glass-cloth-containing polytetrafluoroethylene (GC-PTFE) was investigated. Previous plasma studies investigated pure PTFE (which does not contain glass cloth) but not GC-PTFE. The effect of Ar + H2O plasma treatment on GC-PTFE was investigated. The Ar + H2O plasma-treated GC-PTFE sheets were thermally compressed to stainless steel (SUS304) foils without using adhesive, and the GC-PTFE/SUS304 adhesion strengths were measured using a 90° peel test. The adhesion strength increased with the increase in the plasma treatment time (0.8 and 1.0 N/mm at 20 s and 300 s, respectively). Thus, strong adhesion between GC-PTFE/SUS304 was achieved without adhesive. This improvement in the adhesion properties of GC-PTFE can be attributed to the generation of oxygen-containing functional groups and the decrease in the surface roughness of the samples. Thereafter, the adhesion properties of GC-PTFE and pure PTFE were compared. Because, unlike pure PTFE, GC-PTFE has no weak boundary layer, GC-PTFE exhibited better adhesion properties than pure PTFE under short plasma treatment times.
Keywords: adhesion; fluoropolymers; glass-cloth-containing polytetrafluoroethylene; metals; plasma.