Krytox functional fluids are fluorinated synthetic oils based on hexfluoropropylene oxide combined with a functional end-group. The end-groups offered include: carboxylic acid, called Krytox 157FS, methyl ester, methylene alcohol, primary iodide, allyl ether and a benzene group. Carboxylic acid, methyl ester and methylene alcohol are listed on TSCA*, while the others are available under the TSCA R&D exemption. Reactions of these groups can be accomplished by employing many of the traditional synthetic methodologies used with their perfluoroalkyl analogues.
FS157 can more rigidly attach to the surface through its functional group and that its fluoroalkylether tail attracts the identical molecular structure of Krytox fluorinated oil, resulting in more tenacious surface adhesion of this lubricant. The FSH series serves as an excellent adhesion promoter and linker molecule for fluorinated oils.