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Alkylated naphthalene  

Customers today expect lubricants to perform even in extreme conditions. To help you meet these expectations, Synesstic™ alkylated naphthalene (AN) base stocks are designed to empower lubricants to deliver durability and optimum performance in many operating environments.

Synesstic AN combines the stability of a polyalphaolefin (PAO) and solubility benefits of an ester, helping formulators extend the performance of synthetic and mineral-oil-based lubricants used in many automotive and industrial applications. Available in 5 and 12 cSt grades, Synesstic AN is listed on the U.S. FDA Inventory of Effective Food Contact Substance Notifications, making it suitable for applications with incidental food contact. In addition, Synesstic AN is H1/HX-1 National Sanitation Foundation (NSF) registered.


Performance advantages

Typical properties*
Synesstic 5 Synesstic 12 chart with flash point and pour point temperatures.
*Typical properties; actual values will vary; not to be construed as specifications; sales specifications available at

Polarity effects on lubricant additives
Compared to esters, alkylated naphthalenes can improve additive effectiveness through less competition for the surface, allowing a more complete additive film.

Polarity molecule charts for base oil + Ester + Addiitive and base oil + AN + additive

Oxidative and hydrolytic stability
The Turbine Oil Oxidation Stability Test (ASTM D943 and usually called TOST) is used to evaluate the oxidative stability of various industrial lubricants in the presence of water. We used this test to compare two ISO VG 46 compressor formulations. In one formulation, we blended a conventional PAO base stock, a polyol ester and an additive. In the other formulation, we replaced the ester with Synesstic 5 AN. In the test, Synesstic 5 AN improved oxidative and hydrolytic stability, offering potential to extend compressor oil lifetime.

Ester, Additive, and AN molecure total acid number by hour

Sludge reduction
Using a Cincinnati Milacron test, we compared a PAO base oil reference with a PAO blended with Synesstic AN 5 and a PAO blended with AN 12. Results demonstrate that the Synesstic AN base stocks increase overall blend solubility and cleanliness.

PAO, PAO + ANS, PAO + AN12 total sludge

Oxidation resistance in SAE 5W-30 engine oils
In the ExxonMobil oxidation screening test, Synesstic 5 AN formulated with Group III base stocks demonstrates improved oxidative stability in engine oils compared to Group III blended with an ester and a Group III.

Group III, group III with ester, and group III with Synesstic 5 AN viscocity increase by time.

Enhanced additive performance
Two tests demonstrate that Synesstic AN complements additive performance, improving lubricant durability and efficiency.

5-30 grade oil IVA VIB test charts

Sequence IVA test (ASTM D6891)
Use of Synesstic AN improves durability due to more effective use of the additives present in the additive package.

Sequence VIB test (ASTM 6837))
Use of Synesstic AN improves efficiency (FEI) due to reduced friction as a result of more effective additive performance.


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