2,5-DI-TERT-BUTYL HYDROQUINONE

PRODUCT IDENTIFICATION
CAS NO. 88-58-4

2,5-DI-TERT-BUTYL HYDROQUINONE

EINECS  NO. 201-841-8
FORMULA [(CH3)3C]2C6H2-1,4-(OH)2
MOL WT. 222.33

H.S. CODE

2907.29

TOXICITY

 
SYNONYMS 2,5-Bis(1,1-Dimethylethyl)-1,4-Benzenediol; DTBHQ;

2,5-Di-tert-butylbenzene-1,4-diol; 2,5-Di-tert-butylhydrochinon (German); 2,5-di-terc-butilhidroquinona (Spanish); 2,5-di-tert-butylhydroquinone (French);

DERIVATION  

CLASSIFICATION

 

PHYSICAL AND CHEMICAL PROPERTIES
PHYSICAL STATE off-white crystalline powder

MELTING POINT

 215 C
BOILING POINT 321 C
SPECIFIC GRAVITY 1.07

SOLUBILITY IN WATER

 Insoluble
pH  
VAPOR DENSITY  

REFRACTIVE INDEX

 

NFPA RATINGS

Health: 1, Flammability: 1, Reactivity: 0

AUTOIGNITION

421 C

FLASH POINT

216 C

STABILITY Stable under ordinary conditions

APPLICATIONS
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.

DTBHQ is used as an inhibitor, antioxidant, and stabilizer. It is useful as an antioxidant for rubber products, a stabilizer, and an anti-skinning agent in paints.
SALES SPECIFICATION

APPEARANCE

 off-white crystalline powder
ASSAY

98.0% min

WATER

0.1% max

TRANSPORTATION
PACKING  
HAZARD CLASS  
UN NO.  
REMARKS (DESCRIPTION OF QUINONE)

Quinone is a group of aromatic compounds containing two opposite carbonyl groups (C=O) and the other two pairs of carbon atoms linked by vinylene group(-CH=CH) in a six-membered unsaturated ring. The carbonyl groups are located in different rings and form various chemical structures which offer important roles to colours. Quinones are used in photography and dye manufacture. Quinones occur benzoquinones, naphthoquinones, anthraquinones, and polycyclic quinones. Though quinones are found in plants and in a few animals, they usually are prepared by oxidation of aromatic amines, polyhydric phenols, and polynuclear hydrocarbons. The reduction of quinone to the corresponding dihydroxy form is an important characteristic reaction. In acidic solution, p-benzoquinone is reduced reversibly to hydroquinone. The so-called quinhydrone electrode, containing equimolar solution of quinone and hydroquinone, is used to determine hydrogen ion concentrations depends on the oxidation-reduction reactions. Hydroquinone and its derivatives used principally in photographic dye chemicals, in medicine, as an antioxidant, and in paints, varnishes, and motor fuels and oils. Hydroquinone and certain derivatives are also used as polymerization inhibitors by direct reacting with peroxy-free radical to tie up free radicals.