Apiezon PFPE 501 Grease

image of Apiezon PFPE 501 grease tube

What is Apiezon PFPE 501 grease?

Apiezon PFPE 501 vacuum grease is a chemically inert, high temperature lubricant.

With an upper operating temperature of 250°C and vapour pressure of 1.3 x 10-12 at 25°C, it is robust, versatile and can be used for sealing and lubricating under the most extreme operating conditions. This includes environments where aggressive chemicals and strong oxidising agents are regularly used.

Apiezon PFPE 501 is also certified H1 food grade by NSF international, who are the global independent body that certify food service equipment and supplies for use to the industry. Having the H1 classification confirms that Apiezon PFPE 501 can be used safely in the food production chain where incidental food contact may occur. To achieve this level of accreditation with NSF, the content in the final product must not exceed 10ppm (parts per million). Find out more here.


What are the properties of Apiezon PFPE 501 grease?

Apiezon PFPE 501 Grease is an ultra-high vacuum grease which:

  • exhibits an extremely low vapour pressure of 1.3 x 10-12 Torr at 25°C
  • provides excellent lubrication
  • can be used at temperatures of up to 250°C
  • is chemically inert
  • can be used in high oxygen environments
  • is certified NSF H1 food grade
  • Available to buy in 100g tubes.


Apiezon PFPE 501 Properties Table:

Typical PropertyApiezon PFPE 501
Main areas of application High temperature 
lubricating vacuum grease
NLGI No. 2
Penetration P60 280
Typical working temperature range °C
-15 to 250
5 to 482
Vapour pressure @ 25°C / 77°F, Torr <1.3 x 10-12
Relative density @ 25°C / 77°F 2.003
4 ball wear scar (mm) ASTM D2266 (40kg) 0.94
Outgassing characteristics ASTM.E 595 TML
Evaporation 24hrs @ 100°C / 212°F 0.02
Oil separation 24hrs @ 100°C / 212°F 2.10
Low temperature torque, g/cm 25°C / 77°F Starting
25°C / 77°F Running

When should Apiezon PFPE 501 grease be used?

Apiezon PFPE 501 has proven to be an excellent sealant and lubricant, particularly in laboratory applications, such as in short path distillation.

Being certified as NSF H1 food grade means that it can be used with machinery such as vacuum pumps, mixers, conveyor belts, and other applications associated with:

    • Blending
    • Bottling
    • Brewing
    • Cooking
    • Cutting
    • Handling
    • Peeling
    • Slicing

Due to its inert chemical nature, this grease is recommended for use under extreme conditions such as in the presence of aggressive chemicals, strong oxidisers or high oxygen levels.

To find out more about Apiezon PFPE 501 Grease or the Apiezon family of silicone-free high vacuum greases manufactured by M&I Materials Ltd, contact our team of experts – contact Apiezon.

Apiezon PFPE 501 Grease Vapour Pressure Graph

Apiezon PFPE 501 FAQs

Q: Is Apiezon PFPE 501 a hydrocarbon grease?

A: No, Apiezon PFPE 501 is a perfluoropolyether based grease.

Q: How do I apply Apiezon PFPE 501?

A: Advice on the best practice for grease application can be found here >

Q: How do I clean off Apiezon PFPE 501?

A: Wipe off excess grease with a lint free cloth. Residual grease can be cleaned using a perfluorinated solvent. For stringent cleanliness a further stage using acetone is recommended.

Q: What is the shelf life of an opened Apiezon container?

A: The complex chemical structure of Apiezon greases gives them strong ‘gettering’ properties, this means that they will readily absorb airborne vapours particularly water, and other hydrocarbons. If volatile vapours are absorbed then the greases will lose their excellent vapour pressure characteristics until these contaminants have been outgassed.

This is why we pack the greases in ‘vapour-proof’ aluminium tubes. As we have no control over the use of the greases once they have been opened we cannot quote a shelf life for the products after opening. Practically, however, if care is taken in re-capping the tubes immediately after use and they are not exposed to volatiles then a long service life should not be a problem.

Apart from absorption of volatiles the products are stable and no other changes would be anticipated in the long term. Apiezon PFPE 501 is perfluoropolyether-based and hence is highly inert and less likely to absorb airborne vapours than the hydrocarbon greases.

Q: Is Apiezon PFPE 501 grease resistant to acidic vapours or chlorine?

A: As Apiezon PFPE 501 is perfluoropolyether-based, it has extremely high resistance to all acids, solvents & corrosives with the exception of PFPE base oils and Lewis Acid catalysts.

Q: Are Apiezon greases suitable for use in an oxygen (or LOX) environment?

A: Due to the small risk of auto-ignition from hydrocarbon-based greases, PFPE 501 is the only product in the Apiezon range suitable for use in this application.

Q: Are Apiezon greases resistant to radiation?

A: Apiezon L and M greases show a degree of radiation resistance with only a comparatively small increase in stiffness after irradiation with 4 MeV electrons to a level of about 1 MGy. After this exposure the lubrication properties of the grease are still satisfactory and this is true at even higher levels of irradiation, although the stiffness increases more rapidly.

At high levels of irradiation small quantities of gases, (mainly methane and ethylene) are evolved so that the grease loses its very low vapour pressure characteristics. Nevertheless Apiezon greases L and M are markedly better lubricants at high irradiation levels than other high vacuum lubricants such as silicones, esters and halogenated products.

Q: Do Apiezon greases show luminescence under UV radiation?

A: With the exception of Apiezon PFPE 501, all of the Apiezon greases show blue luminescence. Full details are in the paper “Long-Lived luminescence from commonly used Apiezon compounds” D.W Cooke, B.L. Bennett. Journal of Luminescence 65:1996. A copy is available on request.

Q: Do Apiezon offer a food-grade grease or lubricant?

A: Yes, Apiezon PFPE 501 is certified by NSF as a H1 compliant food-grade grease / lubricant.

Q: Has the Apiezon PFPE 501 formulation changed to make it food-grade compliant for NSF H1 certification?

A:  No, there has been no change to the formulation of Apiezon PFPE 501.

Q: What happens to Apiezon greases above their melting point?

A: All the greases (apart from Apiezon H grease) liquefy but then return to their normal state and properties on cooling, providing the temperature rise has not been excessive. The melting point of Apiezon PFPE 501 is higher than its 250°C operating temperature limit, which should not be exceeded (see respective Safety Data Sheet).

Where to Buy:

Ask Apiezon

CALL: +44 (0)161 864 5409

Ask Apiezon

CALL: +44 (0)161 864 5409

Technical Data Sheet


Safety Data Sheet (SDS)