Ultra-hydrophobic fluorine polymer by Ar-ion bombardment

A study has been made of the improvement of the hydrophobicity of a fluorine-polymer (polytetra-fluorinethylene, PTFE) by Ar-ion bombardment. Ar-ion bombardment to PTFE) by Ar-ion bombardment. Ar-ion bombardment to PTFE sheets was carried out at the fluences ranging from 3.1 x 10(20) to 18.3 x 10(20) ions/m(2). The beam current densities were ranged from 1.25 to 7.5 A/m(2). The hydrophobicity of modified materials has been investigated by means of a sessile drop method of water. The roughness, morphology and structure of bombarded specimens have been estimated as a function of beam current density and acceleration energy. It was found that Ar-bombardment causes the contact angle of water to increase from the original value 103 to 170 degrees. The results indicate that Ar-bombardment at an optional condition results in the formation of ultrahydrdophobic surfaces. The effects of Ar-bombardment to hydrophobicity of PTFE are discussed with the relationship among roughness, morphology and chemical bonding states of the surfaces. (C) 2000 Elsevier Science B.V. Ail rights reserved.