HATCOL® 2938

Synthetic esters are chemicals that are manufactured via the chemical reaction between carboxylic acids and alcohols. Given the large toolbox of readily available raw materials, the properties of synthetic esters can be tailored to afford versatile and high-performing products.

Synthetic esters are used when their properties offer performance advantages versus other commonly used base oils. The properties of synthetic esters can be customized to fit the intended application. This explains why there are so many to choose from. For example, various esters provide excellent thermal stability, lubricity, high flash points, low pour points, and improved additive solubility. Not every ester has all of these properties, but LANXESS has the expertise to help you choose the best one to fit your needs.

Since esters are a diverse class of chemicals, several classification schemes can be used. At LANXESS, we divide our Hatcol® synthetic esters into the following types:

· Monoesters: Low viscosity, good lubricity, less volatile than a hydrocarbon of similar molecular weight.

· Diesters (adipates, sebacates): Good low-temperature properties, high viscosity indices, and biodegradability.

· Aromatic esters (phthalates, trimellitates): High temperature stability, low coking tendency, good miscibility with other base oil types.

· Polyol esters (based on hindered polyols): Excellent high-temperature stability; ideal for critical applications such as turbine oils, high temperature applications, and refrigeration compressor lubricants. They are available in a broad range of viscosity grades.

· Complex esters (polymeric structures): Access to higher viscosities while maintaining biodegradability and improving viscosity index (VI).

Synthetic esters generally outperform mineral oils in terms of thermal stability, oxidation resistance, evaporation loss, and biodegradability.

Synthetic esters are used in a wide range of applications, including:

· Aviation turbine engine oils: Excellent high-temperature stability combined with load-carrying ability

· Automotive lubricants: Improved additive solubility, shear stability, balanced seal compatibility, low evaporation loss

· Hydraulic fluids: High flash points and biodegradability

· Refrigeration compressor lubricants: Good compatibility (miscibility) with refrigerant gases, high temperature stability, long lifetime

· High temperature chain oils: Low volatility, high flash points, incidental food contact

Yes. Synthetic esters are often more environmentally friendly than mineral oils. Many esters are biodegradable and they can be made from renewable resources. Since synthetic ester formulations can provide longer lubricant lifetimes (longer drain intervals), less lubricant is required over the life of a piece of equipment, which reduces environmental impacts associated with excessive lubricant usage.

In case you need recommendations or guideline formulations for your specific applications, please contact our Application Technology team.

No. The esters offered under the Hatcol® brandname are quite “oil-like.” They are only very sparingly soluble in water.

· Total Acid Number (TAN) – A measure of residual acid in the product. Lower is better. Finished lubricant esters should have a TAN below about 0.05 mg KOH/g. Acidity can reduce hydrolytic stability and shelf life.

· Hydroxyl Value – A measure of residual alcohol in the product. Lower is better, generally less than about 5 mg KOH/g, with less than 2 mg KOH/g being preferred. Synthetic esters with high hydroxyl values do not perform well in oxidation-corrosion tests.

· Soap Content – A measure of residual basic material (usually salts of fatty acids) in the product. Soaps can cause hazing and demulsability problems.

· Trace Elements – These include metals, such as iron and tin, as well as sulfur and phosphorus. Trace elements can be the residues of catalysts used to facilitate the esterification process. With modern analytical methods, many elements are detectable down to low ppm levels. Contamination with unwanted elements can decrease shelf life and lower high temperature stability.

· Water Content – Esters tend to absorb water from humid air. Water is also a by-product of the manufacturing process. Proper drying of ester base stocks is important to protect against hydrolysis (degradation that leads to an increase in acidity) during storage.