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Didodecyl
3,3'-thiodipropionate; 3,3'-Thiodipropionic acid di-n-dodecyl ester; Propionic acid, 3,3'-thiodi-, didodecyl ester;
Bis(Dodecyloxycarbonylethyl) Sulfide; Dilauryl beta',beta'-thiodipropionate;
Dilauryl beta-thiodipropionate; Dilaurylester kyseliny
beta',beta'-thiodipropionove; |
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Antioxidant is a
substance added in small quantities to hydrocarbons which are susceptible to
oxidation, such as rubbers, plastics, foods, and oils to inhibit or slow
oxidative processes, while being itself oxidized. Antioxidants work in two
different ways. In primary antioxidants (also called free-radical scavengers),
antioxidative activity is implemented by the donation of an electron or hydrogen
atom to a radical derivative. These antioxidants are usually hindered amines
(p-Phenylene diamine, trimethyl dihydroquinolines, alkylated diphenyl amines) or
substituted phenolic compounds with one or more bulky functional groups such as
a tertiary butyl at 2,6 position commonly. Butylated hydroxytoluene (BHT) is a
common example of hindered phenolic antioxidant. The reaction rate, or
carbocation stability, in SN1 mechanism is 3° > 2° > 1° >
CH3 (no SN1) so, tertiary alkyl moiety exists in lots of
phenolic antioxidant compounds. Primary antioxidants are free radical scavengers
which combine with peroxy radicals and break autocatalytic cycle. In secondary
antioxidants ( also called peroxide decomposers), activity is implemented by the
removal of an oxidative catalyst and the consequent prevention of the initiation
of oxidation. Examples of peroxide decomposer type of antioxidant are trivalent
phosphorous and divalent sulfurcontaining compound such as sulfides,
thiodipropionates and organophosphites. Synergistic effect is expected when
primary antioxidants are used together with secondary antioxidants as primary
antioxidants are not very effective against the degradation by UV oxidation.
Sometimes, chelating agents are added to scavenge metal impurities which can
initiate decomposition.
Didodecyl 3,3-thiodipropionate
is used as a secondary stabilizer and antioxidant
in combination with phenolic antioxidant for
polymers (ABS, polypropylene, polyethylene
and polyesters). It is approved to use in food packaging.
It is also used stabilizer in oils, lubricants, sealants, and adhesives.
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