Synthetic Esters Enable Sustainable Lubrication – Peter Greven
Tuesday, 30 November 2021
Stronger commitment to environmental protection and tightening legal regulations increase the
need for sustainable lubrication in the form of bio-lubricants. As synthetic esters are based on natural fatty acids derived from renewable sources, their use as base oils is gaining in importance as well.
Why are synthetic esters suitable for bio-lubricants?
Bio-lubricants can be defined by three main characteristics:
- Based on renewable raw materials
- Not hazardous to the environment Synthetic esters, as for example the LIGALUB® product range of Peter Greven, can fulfil all these requirements. They offer a high biogenic share, with many products being at 80 % or higher and are classified as not endangering the environment according to directive (EG) 1272/2008. They also show great performance with regard to biodegradability: almost all products are not only biodegradable according to OECD 301 B, but even readily biodegradable.
What about the performance of synthetic esters?
Synthetic esters are high quality products and enable the production of high-performance lubricants.
The range of synthetic esters is highly diversified and so are their strengths. It might not be possible
to find the one product that fits all performance needs at once. But this not only applies to the use of
synthetic esters. It is rather due to the fact that some performance characteristics are contrary.
Every product has its advantages. While, for example, saturated products usually show a very good
oxidation stability, unsaturated products provide better wear values.3 Therefore, it is essential to
know the application and the performance requirements of the formulated lubricant. With this key
information it is possible to find a base oil that perfectly fits the application needs and provides an
Application example: grease
In general, lubricating greases consist of 70 – 95 % base oil, 3 – 30 % thickener, 0 – 10 % additives and
at most around 10 % solid lubricants. Mineral oils and synthetic esters are suitable base oil
alternatives while metallic soaps and non-metallic soaps are usually used as thickeners.
Regarding the thickeners, metallic soaps and also some of the non-metallic soaps are natural,
biodegradable products and therefore eligible for the use in sustainable greases.
With an average share of around 80 %, base oil is the major component of a grease. Even if a
sustainable thickener is used, a grease based on mineral oil is not biodegradable and will therefore
never be able to meet the criteria for biolubricants. This changes if an ester is used as a base oil: as
they fulfil the criteria for biolubricants, synthetic esters pave the way for sustainable greases.
If an ester is used instead of mineral oil, it can enable the same performance of the fully formulated
grease. In terms of durability there might be a little more additivation necessary with synthetic esters
used while the lubricity results might be even better as the esters outperform mineral oil based
products in that area.
As per our knowledge and experience from the past years, high viscosity complex esters and low
viscosity polyol esters or mixtures of both are perfectly suitable for grease production.
In case you have any questions or requirements regarding synthetic esters, please do not hesitate to get in touch with us!
Peter Greven GmbH & Co. KG
Peter Greven will exhibiting at Lubricant Expo 2022. Visit them on stand 729.