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Styrene oxide is a main metabolite of styrene in humans or animals, resulting from oxidation by cytochrome P450. It is considered possibly carcinogenic from gavaging significant amounts into mice and rats. [4] Styrene oxide is subsequently hydrolyzed in vivo to styrene glycol by epoxide hydrolase. [5]
Styrene is regarded as a "known carcinogen", especially in case of eye contact, but also in case of skin contact, of ingestion and of inhalation, according to several sources. [20] [33] [34] [35] Styrene is largely metabolized into styrene oxide in humans, resulting from oxidation by cytochrome P450.
as the first step of the aerobic styrene degradation pathway. [1] The product 2-phenyloxirane is also known as styrene oxide and can be converted by a styrene oxide isomerase (SOI) to obtain phenylacetaldehyde, which can be transformed into the key-intermediate phenylacetic acid by a phenylacetaldehyde dehydrogenase (PAD).
The systematic name of this enzyme class is styrene-oxide isomerase (epoxide-cleaving). This enzyme is also called SOI. This enzyme participates in styrene degradation and is the second step of the pathway after the epoxidation of styrene by styrene monooxygenase. SOI is an integral membrane protein consisting of four transmembrane helices.
The styrene monomer (from which polystyrene is made) is a cancer suspect agent. [109] Styrene is "generally found in such low levels in consumer products that risks aren't substantial". [110] Polystyrene which is used for food contact may not contain more than 1% (0.5% for fatty foods) of styrene by weight. [111]
Typical laboratory operations employ the Prilezhaev reaction. [10] [11] This approach involves the oxidation of the alkene with a peroxyacid such as mCPBA. Illustrative is the epoxidation of styrene with perbenzoic acid to styrene oxide: [12] The stereochemistry of the reaction is quite sensitive.
Poly(p-phenylene oxide) (PPO), poly(p-phenylene ether) (PPE), poly(oxy-2,6-dimethyl-1,4-phenylene), often referred to simply as polyphenylene oxide, is a high-temperature thermoplastic with the general formula (C 8 H 8 O) n. It is rarely used in its pure form due to difficulties in processing.
The polymerization of butadiene and styrene and/or acrylonitrile, such as acrylonitrile butadiene styrene (ABS), nitrile-butadiene (NBR), and styrene-butadiene (SBR). These copolymers are tough and/or elastic depending on the ratio of the monomers used in their preparation. SBR is the material most commonly used for the production of automobile ...