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Bisphenol A is difunctional and used to produce epoxy resin and polycarbonate. 4-tert-Butylphenol is monofunctional and so in polymer science terms, bisphenol A is a polymer chain extender but 4-tert-butylphenol is a chain stopper or sometimes called endcapper. It is thus use to control molecular weight by limiting chain growth.
Firstly, 2,4-dimethyl-6-tert-butylphenol is reacted with formaldehyde and HCl (Blanc reaction) to generate a chloromethyl group in the less hindered meta position. This intermediate then reacts with cyanuric acid to give the desired product.
2,4-Di-tert-butylphenol (2,4-DTBP) is a white solid with a phenolic odour. It is primarily used as a raw material for the production of several commercially important antioxidants and phenolic benzotriazole -type UV absorbers .
Like many closely related phenol antioxidants, BHT has low acute toxicity [6] (e.g., the desmethyl analog of BHT, 2,6-di-tert-butylphenol, has an LD 50 of >9 g/kg [11]). The US Food and Drug Administration classifies BHT as generally recognized as safe (GRAS) food preservative when used in an approved manner.
The health effects of BPA have been the subject of prolonged public and scientific debate. [12] [13] [14] BPA is a xenoestrogen, exhibiting hormone-like properties that mimic the effects of estrogen in the body. [15] Although the effect is very weak, [16] the pervasiveness of BPA-containing materials raises concerns, as exposure is effectively ...
The oxidation of 2,4,6-tri-tert-butylphenol in the alkaline to the intensely blue-colored phenoxy radical can also occur with potassium ferricyanide. [1] [9] [6] The 2,4,6-tri-tert-butylphenoxy radical forms blue crystals on cooling to -70 °C which are stable at room temperature for several weeks and only gradually turn yellow. [9]
UV-328 is a light stabilizer for a variety of plastics and other organic substrates. Its use is recommended for the stabilization of styrene homopolymers and copolymers, acrylic polymers, unsaturated polyesters, polyvinyl chloride, polyolefins, polyurethanes, polyacetals, polyvinyl butyral, elastomers and adhesives. [5]
In polymer chemistry, polymerisation inhibitors (US: polymerization inhibitors) are chemical compounds added to monomers to prevent their self-polymerisation. Unsaturated monomers such as acrylates, vinyl chloride, butadiene and styrene require inhibitors for both processing and safe transport and storage.