Properties and use of perfluoro polyethers for vacuum applications

Abstract

Perfluoro polyether are fully fluorinated fluids. They are chemically inert and excellent lubricants. For vacuum use they have the added advantage that solid films are rarely deposited when the vapors are subject to electron and ion bombardment. The development of various vacuum fluids is discussed, together with physical properties such as mass range, boiling range, viscosity, vapor pressure, and chromatography measurements. Performances of the specially developed fluids in vacuum pumps are presented together with field experiences in a variety of applications.