O-Ring Sealants

What are o-ring seals?

O-rings are round loops of elastomer, designed to be seated and compressed in a groove to create a seal at the join between two or more parts.

While a well-fitted o-ring should not always require grease, in some applications it is beneficial to use a small amount to help with sealing. Apiezon greases have been extensively used as sealants for a variety of temperature and vacuum applications thanks to their versatile nature.

Apiezon greases not only enhance sealing performance, they also make o-rings easier to install and remove.


What are the best Apiezon greases for o-ring seals?

Apiezon hydrocarbon greases manufactured by M&I Materials Ltd are silicone-free, hydrocarbon based products and are compatible with a wide range of o-ring materials including viton, silicone, nitrile (>30% nitrile content), nylon, polyurethane, polyethylene and polypropylene.

They are also highly creep resistant. Due to their hydrocarbon formulation, these are not compatible with EPDM (ethylene propylene diene M-class rubber), EPR (ethylene propylene rubber), Butyl rubber and PVC.

Apiezon PFPE 501 is compatible with all commonly used o-ring materials and can be relied upon to provide sealing properties under extreme conditions such as ultra-high vacuum conditions and in the presence of gaseous and liquid oxygen at elevated temperatures.

All Apiezon greases have excellent vapour pressure characteristics, an important factor for a variety of applications, including thin film deposition, as volatiles will not jeopardize the vacuum within the system or contaminate the thin film deposits.

Apiezon greases for o-ring seals FAQs

Q: How should I apply grease to an o-ring?

A: Our advice is that you don’t always need to use grease with an o-ring if it fits properly and is completely clean. If you decide grease is necessary, clean the o-ring as much as possible before applying a thin film of grease.

The easiest way to do this is to apply a small amount of grease between two fingers with a gloved hand. Excess grease should then be wiped away to leave a very light smear that can be seen as a sheen on the o-ring.

Q: What o-ring materials are compatible with Apiezon PFPE 501 grease?

A: Apiezon PFPE 501 is perfluoropolyether-based and is compatible with all commonly found plastics, rubbers and polymers.

Ask Apiezon

Do you have a technical question regarding Apiezon products?

CALL: +44 (0)161 864 5409

Ask Apiezon

Do you have a technical question regarding Apiezon products?

CALL: +44 (0)161 864 5409

Where to Buy:


Apiezon Product Range