Novel One-Component Anisole- and Hydroxyl-Terminated Perfluoropolyethers for Boundary Lubrication

The tribological properties of some novel single component perfluoropolyether (PFPE) boundary lubricants with chemically integrated mixture end groups are investigated. Chemically integrated mixture end groups composed of hydroxyl- and anisole-terminated PFPE boundary lubricant films on the –(CF2CF2CF2O)– main chain are reported. These PFPE-based boundary lubricants explore a new method by which single component PFPE lubricants with mixture end groups might be used to tailor boundary film properties instead of using physical mixtures of two or more PFPEs with different end groups. Lubricant transfer to the low-flying read/write head, head wear, and siloxane adsorption as a function of PFPE film thickness and of type are compared. Normalization of the data to the monolayer fraction instead of film thickness allows direct comparison between anisole- and hydroxyl-terminated PFPEs. Lubricant transfer to the head and head wear are independent of the functional end groups. Siloxane adsorption decreases with increasing anisole substitution of the hydroxyl groups. One-component PFPEs with mixed end groups provide a methodology by which boundary film properties could be adjusted.