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In the simplest terms, esters can be defined as
the reaction products of acids and alcohols. Thousands of
different kinds of esters are commercially produced for a broad
range of applications. Within the realm of synthetic
lubrication, a relatively small but still substantial family of
esters have been found to be very useful in severe environment
applications. This page provides a general overview of the more
common esters used in synthetic lubricants and discuss their
important benefits and utilities.
Ester Chemistry
Esters have been used successfully in lubrication
for more than 50 years and are the preferred stock in many
severe applications where their benefits solve problems or bring
value. For example, esters have been used exclusively in jet
engine lubricants worldwide for over 40 years due to their
unique combination of low temperature flowability with clean
high temperature operation. Esters are also the preferred stock
in the new synthetic refrigeration lubricants used with CFC
replacement refrigerants. In automotive applications, the first
qualified synthetic crankcase motor oils were based entirely on
esters and these products were quite successful when properly
formulated.
The polarity of the ester molecules causes them
to be attracted to one another and this intermolecular
attraction requires more energy (heat) for the esters to
transfer from a liquid to a gaseous state. At a given molecular
weight or viscosity, the esters will exhibit a lower vapor
pressure which translates into a higher flash point and a lower
rate of evaporation for the lubricant. In general, the more
ester linkages in a specific ester, the higher its flash point
and the lower its volatility.
Polarity also causes the ester molecules to be
attracted to positively charged metal surfaces. The result is a
stronger film which translates into higher lubricity and lower
energy consumption in lubricant applications. The polar nature
of esters also makes them good solvents and dispersants. This
allows the esters cleaner operation and improved additive
solubility in the final lubricant. While stable against oxidative and thermal
breakdown, the ester linkage provides a vulnerable site for
microbes to begin their work of biodegrading the ester molecule.
ester lubricants are more environmentally friendly products to
be formulated.
Ester Families
Polyol Esters
In our family of polyol ester are
made by reacting trimethylolpropane, pentaerythritol, and
dipentaerythritol alcohols with monobasic acids.
Typical usages include raw material for spin finishers and
oiling agents, lubricants, lubricating oil, and as solvent for
agrochemicals.
More...
Monobasic Esters
Hatcol esters series includes
range of high purity esters that often replace mineral oils in
various applications where they provide unique tactile
qualities. These products include stearates, palmitate and decanoates. They find usages as raw material for surfactants,
cosmetic base, additives for pharmaceuticals, and friction
modifier.
More...
Dibasic Esters
Diesters are made by reacting monohydric alcohols
with dibasic acids creating a molecule which may be linear,
branched, or aromatic and with two ester groups.
These products include adipates, sebacates, dodecanedioates, and
phthalates. They find usages as raw material for spin finishes
and oiling agents for textile, rubber processing agent, plastic
lubricant, paint additive, and ink additive.
More...
Tribasic Esters
triesters are similar to diesters but with a
third ester linkage.
Hatco offers a wide range of
trimellitates for use in applications where lubricity,
hydrolytic stability and low odor are critical. Usages include
oiling agent for textile, plastic lubricant, and additive for
plastic processing.
More...
For more specific information
about any of these product lines or products, please feel free
to contact us and we shall be happy to provide you with
additional literature.
You can email us at hatcoinfo@chemtura.com or submit your requirements
using our
Ester Design Sheet. Either way you can
count on prompt and confidential service.
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