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As each phenol group contains only a single t-butyl group they are considered to have low steric hindrance and thus high activity. Arranging three of these around an isocyanurate core gives a compound with a sufficiently high boiling point that it is not volatilised out of the plastic during plastic extrusion and moulding (up to 320 °C in the case of PA).
Tris(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate is a chemical compound used as a polymer stabilizer in plastics. Like other hindered phenols it acts as a primary antioxidant. More than 1000 tonnes per year are used in the EU.
Bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite is an organophosphite used as a polymer stabilizer in plastics. Like other phosphite antioxidants it primarily acts to remove hydroperoxides and is typically used in combination with hindered phenolic antioxidants such as pentaerythritol tetrakis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate) .
Bosentan is contraindicated in people taking glyburide due to an increased risk of increased liver enzymes and liver damage when these two agents are taken together. [4]Use of bosentan with cyclosporine is contraindicated because cyclosporine A has been shown to markedly increase serum concentration of bosentan.
Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate is significantly less volatile than simpler phenolic antioxidants such as butylhydroxytoluene (BHT). This makes it more suitable to stabilising plastics, as it is not driven out by the high temperatures experienced during plastic extrusion and moulding, [2] when they are heated to 150-320 °C (300–600 °F). [3]
Terbutaline, sold under the brand names Bricanyl and Marex among others, is a β 2 adrenergic receptor agonist, used as a "reliever" inhaler in the management of asthma symptoms and as a tocolytic (anti-contraction medication) to delay preterm labor for up to 48 hours.
Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate - an inexpensive and commonly used polymer stabiliser; Tris(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate - a polymer stabiliser commonly used to protect against long term heat aging; Irganox 1098 - a polymer stabiliser with metal chelation properties
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.