Recently, the application of polytetrafluoroethylene (PTFE) spreads through the various fields. PTFE is macromolecular material that has repetition of two fluorine atoms combined to a carbon atom. Because these atoms are combined strongly, the material has various excellent characteristics such as heat-resistant, electrical insulation, chemical proof, low friction, etc. Because of these characteristics it’s used in a wide field, such as semiconductors, chemistry, machines, food, etc. It is expected the functional PTFE modified on its surface can be used in larger fields.

In this study, the surface of PTFE was modified by using the ion beam irradiation method. The irradiated ion species were H⁺, He⁺, Ne⁺ and Ar⁺ ion. These ion beam irradiations were performed with 10 kV in an acceleration voltage at 10 and 40 μA/cm² in a current density. The modified effects on the surface were evaluated about water repellency and same mechanical properties.

The water contact angle was measured by a contact angle meter using the θ/2 method. Surface morphology was observed by scanning electron microscope. Surface chemical-bonding state was investigated by X-ray photoelectron spectroscopy.

The morphology and chemical bonds of the surface changed by irradiated ion species. The water contact angle of the PTFE surface irradiated by Ar⁺ ion beam increased to about 40 % in comparison with the unirradiated PTFE. On the other hand, the water contact angle of the PTFE surface irradiated by He⁺ ion beam decreased to about 30 %. The PTFE could obtain hydrophilicity or repellency on the surface by ion beam irradiation. The surface morphology showing repellency changed to a spicule structure, while the surface showing hydrophilicity changed in the chemical state.