Improved Surface Adhesion and Coverage of Perfluoropolyether Lubricants Following Far-UV Irradiation

Far-UV treatment of a surface with a thin film of a perfluoropolyether improves adhesion and lowers surface free energy substantially compared to the unirradiated, lubricated surface. With 185-nm radiation, approximately one monolayer can be “fixed” to surfaces such as amorphous carbon, silica, and gold. These lubricated surfaces become extremely hydrophobic after UV treatment (advancing water contact angle increases from about 65° to S 110°) and are not removed by fluorinated solvents. In the absence of far-UV radiation, most perfluoropolyethers show poor adhesion to carbon and are removed easily by rinsing with fluorinated solvents. © 1990, American Chemical Society. All rights reserved.