Perfluoropolyether (PFPE) oils are chemically inert, capable of handling extreme temperatures and also hazardous operating environments, PFPEs are resistant against fuels, solvents and chemicals, examples such as sulphuric acid and sodium hydroxide. PFPEs are composed entirely of carbon, fluorine and oxygen. PFPE summary:
- Temperature range of -90 to 250°C
- Low vapour pressure
- Excellent plastic compatibility
- High cost and high density
- Not good at dealing with heavy loads
- Poor solubility of additives, so not a great range of additive options
- Resistant to low levels of radiation
- Viscosity Index 100 to 350
Keep in mind that if a PFPE is used as the base oil for a grease, the thickener and additives also used in the formula will have an influence on the final characteristics and performance of the finished grease/lubricant.
This article is only intended as a basic introduction into PFPE oils/fluids, there are different types of PFPE all of which have their particular characteristics.