Apiezon L Hydrocarbon Greases

Specifications Table

Vapor Pressure	@20°C: 7 x 10-11
Specific Gravity	0.896 (g/cc)
Melting Point	42-52 (°C)
Temperature Range	10-30 (°C)
Thermal Conductivity	@20°C: 0.194 (w/m °C)
Lubricity 4 Ball Test	150 (kg)
Outgassing Characteristics	TML: <1% CVCM: <0.1%
Viscosity of Molten Grease	@50°C (cP), 766 @100°C (cP), 62.3
Radiation Resistance	Yes
Coeff. of Expansion	20°C-30°C: 0.00076 cm/°C
Volume Resistivity	1.2 x 1016 (ohm cm)
Permitivity	2.3
Loss Tangent	<0.0001
Surface Breakdown at Flash Over	24 (kV)
Electric Strength	730 (V/mil)

Charts

High Vacuum

Apiezon L grease has the best vapour pressure properties of all the hydrocarbon products and can be used in ultra-high vacuum applications. The vapour pressure for Apiezon L grease over its working temperature range is shown in the graph opposite.

Ambient temperatures

Apiezon L grease is typically used at ambient temperatures. If a high temperature or cryogenic vacuum grease is required, Apiezon H grease or Apiezon N grease should be evaluated.

Long lasting lubrication

Apiezon L grease has been especially formulated to provide excellent lubrication while maintaining an efficient seal and is widely used in the manufacture and servicing of high-performance vacuum pumps.

Silicone free

As a hydrocarbon-based grease, Apiezon L grease is highly resistant to 'creep' or 'carry over', a phenomenon associated with silicone-based products. Silicone tends to travel away from the area of application and contaminate adjacent surfaces.

The creep resistance of Apiezon hydrocarbon greases benefits scientific users as it reduces sample contamination and the risk of interference in analytical techniques such as infra-red and mass spectrometry. Silicone contamination is of particular concern in surface coating applications such as industrial paint or metal deposition processes, as trace amounts of silicone on surfaces prevent the adherence of paint and poor or incomplete coverage results.

In semiconductor manufacture, yields can be severely affected by silicone contamination. When using Apiezon hydrocarbon greases, the problems associated with silicone creep and contamination are avoided.

Easily Removed

Apiezon hydrocarbon greases are easily removed by wiping with a soft, clean lint free cloth. Any residues of grease can be washed away with warm soapy water or by using any aromatic hydrocarbon solvent (toluene, xylene).

For a more environmentally friendly solvent, we recommend limonene. Apiezon hydrocarbon greases are not soluble in alcohols (ethanol, IPA) or ketones (acetone, MEK) so these cannot be used for cleaning.

'Gettering' action

Apiezon hydrocarbon greases are manufactured from a unique feedstock containing a high proportion of branched and unsaturated structures. These give the greases a very high molecular weight and consequently strong powers of absorption, particularly for other hydrocarbon molecules.

Strong absorption properties ensure that Apiezon hydrocarbon greases have a powerful 'gettering' action, i.e., the power to absorb greasy or chemical impurities on metal and glass surfaces.

This is of value in the electronics industry where scrupulous cleanliness is required. Apiezon hydrocarbon greases have no contaminating effect on electrical equipment and are easily removed by hydrocarbon solvents. This process takes with it many trace impurities which are not removed by solvents alone.

Apiezon L grease is also frequently used as the stationary phase in gas chromatography because of its strong absorption properties.

Compatibility

Apiezon L grease is compatible with a wide range of O-ring materials including:

• Viton
• Silicone
• Nitrile (>30% nitrile content)
• Nylon
• Polyurethane
• Polyethylene
• Polypropylene

Due to its hydrocarbon base, Apiezon L grease is not compatible with:

• EPDM (ethylene propylene diene M-class rubber)
• EPR (ethylene propylene rubber)
• Butyl rubber
• PVC seals

Shelf life

The shelf life of L grease is ten years from date of manufacture, providing the product is in the original unopened packaging and has been stored at ambient (10 to 30°C) temperature.