Apiezon® L grease has been specifically developed for vacuum use, but it can also be used in a variety of industrial and scientific applications. Apiezon® L is a low vapor pressure, hydrocarbon grease that has the best vapor pressure properties of all the Apiezon® products, and is used in the ultra high vacuum (UHV) range. Apiezon® L grease resists the “creep” phenomenon, so it will not contaminate or interfere with analytical techniques such as IR and MS. The L grease is approved by industries all over the world including: The European Space Agency, Matra Marconi, NASA, and NATO. Apiezon® L also contains built-in resistance to irradiation, and is better lubricant than ester silicones and halogenated paraffins, which decompose at levels of 10 Mrads or less. The complex structure and high molecular weight of Apiezon® L grease gives it strong absorption properties to be used as a stationary phase in gas chromatography. Apiezon® L grease is specifically formulated to maintain efficient gas seals in the high performance vacuum pump industry.
An ideal general-purpose vacuum grease and ground-glass joint sealant
Silicone and halogen free
Widely used as a stationary phase in GLC
Ultra high vacuum range
Radiation resistant (100 Mrads)
Apiezon® L grease has no contamination effect on electrical equipment and is easily removed through use of water, soapy water, hydrocarbon solvents (Limonene, Toluene, Xylene) or chlorinated solvents (Trichloroethylene). When Apiezon® L is removed, it also takes away trace impurities that are not removed by solvents alone.
Vapor Pressure (Torr)
@20°C: 7 x 10-11
@20°C: 0.194 (w/m °C)
Lubricity 4 Ball Test
TML: <1% CVCM: <0.1%
Viscosity of Molten Grease
@50°C (cP), 766 @100°C (cP), 62.3
Coeff. of Expansion
20°C-30°C: 0.00076 cm/°C
1.2 x 1016 (ohm cm)
Surface Breakdown at Flash Over
As shown below, Apiezon® L grease has extremely low vapor pressures at ambient temperatures so it can be used in ultra high vacuum (UHV) ranges. This allows Apiezon® L grease to have vapor pressures lower than 10-10 torr at ambient temperatures (20 °C).
Apiezon L Vapour Pressure
Chart:Apiezon L Vapour Pressure
It is strongly recommend using all fluids and greases at the time of receipt, however when storage is necessary, rotate older stock into use first and observe the recommended parameters listed below.
All Apiezon products have a shelf life of 10 years if unopened in their original container and stored at ambient temperatures. If the product has been opened, resealed and then stored in clean, dry, dark environment under ambient conditions in the original container, it should last up to 10 years, but this is not guaranteed.