86 | www.CosmeticsandToiletries.com Vol. 130, No. 4 | May 2015
Ethylhexylglycerin is a frequently used multifunctional additive. Beside its deodor- ant efficacy, it is an excellent booster of many
traditional preservatives and other antimicrobial
substances. It was introduced into the personal
care market by schülke as sensiva® SC 50; a product with outstanding quality and comprehensive
The stabilization of ethylhexylglycerin in
sensiva® SC 50 guarantees that the high purity is
maintained for the entire shelf–life of the material.
This stabilization system has been patented by
schülke. Unstabilized ethylhexylglycerin can form
unidentified impurities with unknown toxicological profiles during storage.
The safety of sensiva® SC 50 is ensured by this
high purity grade of ethylhexylglycerin having an
extremely low impurity profile. Due to its patented
stabilization, this purity is ensured for the entire
shelf-life of the material. Beyond that, sensiva® SC
50 has been used in toxicological studies showing
that no side effects coming from its few impurities
are to be expected.
sensiva® SC 50-grade ethylhexylglycerin does
not pose an increased risk for acquiring a contact
allergy after exposure. This was proven in sensitization assays to determine the allergic potential
according to Magnusson-Kligman and a local
lymph node assay (LLNA).
Other qualities of ethylhexylglycerin without
stabilization are now available to the personal care
market. Depending on the origin, a significant
portion of unknown impurities can be present in
the fresh material. Additionally, these variants may
not guarantee a constant quality. Due to the ether-function, decomposition can occur in unstabilized
ethylhexylglycerin. Thus, more impurities with
By: schülke, Inc.
Pure Quality by Patented
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unknown toxicological profiles can develop during storage.
Against this background, it should be considered that the
use of impure material could provoke an increased risk of
allergies not originally triggered by the main substance,
thereby potentially discrediting a valuable molecule.
The Issue of Aging
Many organic substances undergo oxidative degradation
(reactions). Specifically, ethers have the potential of forming peroxides if exposed to air. This is also a concern for
polyethers, like ethoxylated surfactants, as has been reported
in the past. Several different breakdown products can be
expected from primary oxidation reactions, like alcohols,
ketones, aldehydes and carboxylic acids. All of these categories of substances are reactive enough to undergo secondary
reactions which each other.
Additionally, 1,2-diols undergo oxidative cleavage reactions, known as glycol cleavage. This reaction is often used
for structure determination of sugars. Ethylhexylglycerin is a
glycerol ether which bears both functional groups, ether and
diol, in the same molecule. This makes it sensitive to ageing
reactions under the influence of air.
Fresh sensiva® SC 50 shows a purity of more than 99%,
which is exceptionally high for cosmetic raw materials.
To keep this purity for the entire shelf-life, schülke has
developed a protection technology utilizing stabilizers, like
As incompatibilities with the skin, such as irritations and
sensitization, are the most threatening side effects of the use
of cosmetic products, stability of the raw materials, as well as
finished products, is of essential importance. Figure 1 shows
a gas chromatogram of freshly distilled ethylhexylglycerin.
Aside from the main peak, there are just a few very small
signals that represent by-products and impurities in an
amount of less than 200 ppm each. Due to the stabilization
technology, sensiva® SC 50 retains this low impurity profile
for its entire shelf-life of three years.