Fluorinated Lubricating Greases and Oils
Composition, characteristics and industrial applications

Amongst synthetic lubricant solutions, fluorinated oils and greases are by far the most effective and durable barrier to protect against the deterioration of numerous mechanical kinematics under extreme operating conditions.

First introduced in the military and aerospace sectors, fluorinated oils or perfluoroalkylethers are linear or multi-branched polymers composed entirely of carbon, oxygen and fluorine. They are colourless, odourless and even totally inert to many chemical agents, including oxygen. They are compatible with many materials and remain fluid, providing unsurpassed lubricating properties over a broad range of operating temperatures.

Fluorinated oils belonging to the family of synthetic lubricating oils are distinguished by their structure into:

• Branched oils > characterised by functional units inserted along the main chain, they are the most widely used in industry due to their favourable price-performance ratio
  
  
• Linear oils > non-branched oils with higher thermoviscous stability serve for uses across a broader temperature range than branched oils

Fluorinated oils (PFPEs) are the precursors of fluorinated greases whose lubricating power is further enhanced by thickeners, solid lubricants (PTFE) and additives to improve rheological and anti-friction properties, in order to allow them to be utilised in application contexts where fluorinated oil alone would not provide adequate performance, such as for the lubrication of rolling bearings or where there is a need for greater adherence to friction zones. Compared to oils, fluorinated greases possess superior:

• Load-bearing capacity
• Protective power 
• Adhesive power to friction areas
• Sealing effect on seals

Unsurpassable thermal limits! Should the operating temperatures of a mechanical device be continuously below -80° C or constantly above 220° C, only with a fluorinated oil or grease will it be possible to guarantee constant hydrodynamic lubrication and, consequently, significantly longer re-lubrication times, being up to 10 times longer than with a mineral lubricant, resulting in drastically-reduced maintenance costs.

Fluorinated greases and oils are commonly used in the automotive, military aerospace, nuclear and all application contexts in which mechanical devices have to operate under critical thermal (low or high operating temperatures) or chemical conditions, including:

• Lubrication of oxygen service valves and O-rings, due to non-flammability and stability in an oxygen-enriched atmosphere
  
  
• A lubricant for aircraft instrumentation with low vapour pressure under atmospheric vacuum conditions
  
  
• As a lubricant in reactive chemical environments, due to chemical inertness, high thermooxidation stability and insolubility in almost all chemical compounds
  
  
• As a high-temperature lubricating grease thanks to its thermal resistance in continuous operation at 300° C and intermittent operation up to 450° C

As demonstrated by the Noack Volatility Test at 250° C, fluorinated oils (PFPE) show significantly lower evaporation loss than all other synthetic oils at the same molecular weight and viscosity.