To enhance processing and end-use performance of petroleum products, additives, stabilizers and antioxidants are used. The effectiveness of these chemicals against weathering depends on its chemical nature and its compatibility with the polymer; solubility, ability to stabilize, its distribution in different polymer matrix, and evaporation loss during processing and use.
TBHQ Tech.
Product Name: TERT-BUTYL HYDROQUINONE (TBHQ) TECH
Synonym: 2-tert-Butyl-1,4-benzenediol
Cas No.: 1948-33-0
Molecular Formula: C10H14O2
Molecular weight: 166.22 g/mol
TBPBQ
DTBHQ is a specialized/effective stabilizer, antioxidant and co-inhibitor. In rubbers, it's used to stabilize against odour and colour development as well as a stopping agent for emulsions. For unsaturated polyesters, it's often combined with other inhibitors for storage stability (extends shelf life with minimal effect on gel time).
Hydroquinone
HYDROQUINONE (Photographic Grade)
IUPAC name : Benzene-1,4-diol
Other names : Hydroquinone, Idrochinone, Quinol , 1,4-Dihydroxybenzene , 1,4-Hydroxy benzene
CAS no :123-31-9
EEC no :204-617-8
Molecular Formula :C6H6O2
Molecular Weight :110.11g/mol
Hydroquinone is an aromatic organic compound that is a type of phenol, and a derivative of benzene. It is available as a white granular solid.
Hydroquinone is produced industrially by two main routes. The most widely used route is similar to the cumene process in reaction mechanism and involves the dialkylation of benzene with propene to give 1,4-diisopropylbenzene. This compound reacts with air to afford the bis(hydroperoxide), which is structurally similar to cumene hydroperoxide and rearranges to give acetone and hydroquinone in acid. A second route involves hydroxylation of phenol. The conversion uses hydrogen peroxide and affords a mixture of hydroquinone and catechol:
C6H5OH + H2O2 → C6H4(OH)2 + H2O
MEHQ/PMP
MEHQ (Methyl Hydroquinone)
IUPAC name: 4-Methoxyphenol
Other names: PMP (para-methoxyphenol) / 4-Hydroxy Anisole/ HQMME(Hydroquinone Mono Methyl Ether)/para-Guaiacol
CAS Number: 150-76-5
4-Methoxyphenol is an organic chemical compound manufactured industrially by the methylation of hydroquinone. It is available in white crystals or flakes in nature with a phenol like odour.
4-MethoxyphenoI is used in industry, mainly as a polymerization inhibitor (petrochemicals), and as a synthesis intermediate (agrochemicals). It is also used as a stabilizer for the formulation of inks, adhesives or additives for the textile and leather industries.
MEHQ may cause some adverse effects on human health. It is harmful if swallowed, causes skin and eye irritation. MEHQ is biodegradable and has a low potential for bioaccumulation, so it will not remain persistent in nature.
4-TBC
4-tert-Butylcatechol (TBC)
IUPAC name: 4-tert-Butylbenzene-1,2-diol
CAS Number: 98-29-3
Molecular Formula: C10H12O2
Molecular Weight: 166.22 g/mol
4-Tert-butyIcatechoI is an organic chemical compound obtained by the butylation of Catechol using Isobutene gas. TBC is available in off-white to amber coloured crystalline solid or flakes. It is mainly used as a polymerization inhibitor or a stabilizer for polymerizable monomers.
TBC is available in different forms such as Flakes, 85% in Water, 85% in Methanol etc. The use of these in production, transportation or storage of monomers depends on its solubility in a particular monomer. The concentration of TBC in monomers varies from one another, in order to inhibit the polymerization.
TBC is harmful to human health, in contact with skin or if swallowed. It is corrosive and causes severe skin burns and eye damage. It may cause an allergic skin reaction. TBC may have a very toxic and long lasting effect to aquatic life.
PBQ
Name: Para-Benzoquinone (PBQ)
Chemical Name: 1,4-Benzoquinone
Synonym: p-Dioxobenzene p-Quinonee
Cas no.: 106-51-4
Molecular Formula: C8H4O2
Molecular Weight: 108.1 g/mol
Para-Benzoquinone is an organic chemical compound commonly known as p-Quinone. It is a bright yellow to light brown coloured crystalline solid with a strong pungent, irritating odour. It is manufactured by the oxidation of hydroquinone. It is used as a polymerization inhibitor and as an intermediate in the production of a variety of substances including rubber accelerators and oxidizing agents.
PBQ is able to stain skin dark brown, cause erythema (redness, rashes on skin) and lead to a localized tissue necrosis.
APPLICATION:
Para-Benzoquinone acts as a cross linking agent and is useful in stabilizing unsaturated polyester resins during processing, shipment, and storage in either catalyzed or per catalyzed form.
Used as a chemical intermediate for the manufacture of the agrochemical herbicide, Ethofumesate and the active pharmaceutical ingredient, Calcium dobesilate.
DTBHQ
2,5-di-tert-butylhydroquinone (DTBHQ) is used as an antioxidant, stabilizer and polymerization inhibitor for synthetic rubbers and plastics. It is white to off-white crystalline powder with a melting point upto 2170 C. It is soluble in alcohol, acetone, ethyl acetate.
DTBHQ is an anti-degradant, anti-oxidant and is being developed to address problems related to degradation over time, stability, etc. enhancing the overall performance of rubber compounds. Unsaturated polyesters (UPR) often combined with inhibitors such as this for storage stability extends shelf life with minimal effect on gel time.