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Bis(2,4-di-tert-butylphenyl) Pentaerythritol Diphosphite
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). Synthesis It is formed by a reaction between phosphorus trichloride, pentaerythritol and 2,4-di-tert-butylphenol. The poor solubility of pentererythritol can be an issue and non-nuncleophilic amines are often used to promote the reaction. Properties and applications Compared to tris(2,4-di-tert-butylphenyl)phosphite (a common phosphite antioxidant) it has higher activity but lower stability against hydrolysis. Trace levels of amine bases are often added to commercial material to slow hydrolysis and increase storage life. It's crystal structure has been determined. It is comparable with a wide range of plastics including polyolefins, en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organophosphite
The general structure of a phosphite ester showing the lone pairs on the P In organic chemistry, a phosphite ester or organophosphite usually refers to an organophosphorous compound with the formula P(OR)3. They can be considered as esters of an unobserved tautomer phosphorous acid, H3PO3, with the simplest example being trimethylphosphite, P(OCH3)3. Some phosphites can be considered esters of the dominant tautomer of phosphorous acid (HP(O)(OH)2). The simplest representative is dimethylphosphite with the formula HP(O)(OCH3)2. Both classes of phosphites are usually colorless liquids. Synthesis ;From PCl3 Phosphite esters are typically prepared by treating phosphorus trichloride with an alcohol. For alkyl alcohols the displaced chloride ion can attack the phosphite, causing dealkylation to give a dialkylphosphite and an organochlorine compound. The overall reaction is as follows: :PCl3 + 3 C2H5OH → (C2H5O)2P(O)H + 2 HCl + C2H5Cl Alternatively, when the alcohol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer Stabilizer
Polymer stabilizers (British English: polymer stabilisers) are chemical additives which may be added to polymeric materials to inhibit or retard their degradation. Mainly they protect plastic and rubber products against heat, oxidation, and UV light. The biggest quantity of stabilizers is used for polyvinyl chloride (PVC), as the production and processing of this type of plastic would not be possible without stabilizing chemicals. Common polymer degradation processes include oxidation, UV-damage, thermal degradation, ozonolysis, combinations thereof such as photo-oxidation, as well as reactions with catalyst residues, dyes, or impurities. All of these degrade the polymer at a chemical level, via chain scission, uncontrolled recombination and cross-linking, which adversely affects many key properties such as strength, malleability, appearance and colour. Stabilizers are used at all stages of the polymer life-cycle. They allow plastic items to be produced faster and with fewer defe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antioxidant
Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants are frequently added to industrial products, such as polymers, fuels, and lubricants, to extend their usable lifetimes. Foods are also treated with antioxidants to prevent Food spoilage, spoilage, in particular the rancidification of Vegetable oil, oils and fats. In Cell (biology), cells, antioxidants such as glutathione, mycothiol, or bacillithiol, and enzyme systems like superoxide dismutase, inhibit damage from oxidative stress. Known diet (nutrition), dietary antioxidants are vitamins vitamin A, A, vitamin C, C, and vitamin E, E, but the term has also been applied to various compounds that exhibit antioxidant properties in vitro, having little evidence for antioxidant properties in vivo. Dietary supplements marketed as antioxidants hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroperoxide
Hydroperoxides or peroxols are Chemical compound, compounds of the form ROOH, where R stands for any group, typically Organic compound, organic, which contain the hydroperoxy functional group (). Hydroperoxide also refers to the hydroperoxide anion () and its Salt (chemistry), salts, and the neutral hydroperoxyl, hydroperoxyl radical (•OOH) consist of an unbond hydroperoxy group. When R is organic, the compounds are called organic hydroperoxides. Such compounds are a subset of organic peroxides, which have the formula ROOR. Organic hydroperoxides can either intentionally or unintentionally initiate explosive polymerisation in materials with saturated bond, saturated chemical bonds. Properties The bond length in peroxides is about 1.45 Ångström, Å, and the angles (R = Hydrogen, H, Carbon, C) are about 110° (water-like). Characteristically, the dihedral angles are about 120°. The bond is relatively weak, with a bond dissociation energy of , less than half the strength ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentaerythritol Tetrakis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)
Pentaerythritol tetrakis(3,5-di-''tert''-butyl-4-hydroxyhydrocinnamate) is a chemical compound composed of four sterically hindered phenols linked through a pentaerythritol core. It is used as primary antioxidant for stabilizing polymers, particularly polyethylene and polypropylene. Synthesis Base catalysed Michael addition of methyl acrylate to 2,6-di-''tert''-butylphenol forms the intermediate dibutyl- phloretic ester. High temperature transesterification of this with pentaerythritol Pentaerythritol is an organic compound with the formula C(CH2OH)4. The molecular structure can be described as a neopentane with one hydrogen atom in each methyl group replaced by a hydroxyl (–OH) group. It is therefore a polyol, specifically a ... gives the final product. Driving this reaction to completion can be difficult and commercial samples often contain low levels of the tri-ester. Properties The linking of phenols together with pentaerythritol maintains their activity with greatly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus Trichloride
Phosphorus trichloride is an inorganic compound with the chemical formula PCl3. A colorless liquid when pure, it is an important industrial chemical, being used for the manufacture of phosphites and other organophosphorus compounds. It is toxic and reacts readily with water to release hydrogen chloride. History Phosphorus trichloride was first prepared in 1808 by the French chemists Joseph Louis Gay-Lussac and Louis Jacques Thénard by heating calomel (Hg2Cl2) with phosphorus. Later during the same year, the English chemist Humphry Davy produced phosphorus trichloride by burning phosphorus in chlorine gas. Preparation World production exceeds one-third of a million tonnes. Phosphorus trichloride is prepared industrially by the reaction of chlorine with white phosphorus, using phosphorus trichloride as the solvent. In this continuous process PCl3 is removed as it is formed in order to avoid the formation of PCl5. :P4 + 6 Cl2 → 4 PCl3 Structure and spectroscopy It has a t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentaerythritol
Pentaerythritol is an organic compound with the formula C(CH2OH)4. The molecular structure can be described as a neopentane with one hydrogen atom in each methyl group replaced by a hydroxyl (–OH) group. It is therefore a polyol, specifically a tetrol. Pentaerythritol is a white solid. It is a building block for the synthesis and production of explosives, plastics, paints, appliances, cosmetics, and many other commercial products. The word pentaerythritol is a blend of ''penta-'' in reference to its five carbon atoms and ''erythritol'', which also possesses 4 alcohol groups. Synthesis Pentaerythritol was first reported in 1891 by German chemist Bernhard Tollens and his student P. Wigand. It may be prepared via a base-catalyzed multiple-addition reaction between acetaldehyde and 3 equivalents of formaldehyde to give pentaerythrose (CAS: 3818-32-4), followed by a Cannizzaro reaction with a fourth equivalent of formaldehyde to give the final product plus formate ion. : Uses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tris(2,4-di-tert-butylphenyl)phosphite
Tris(2,4-di-tert-butylphenyl)phosphite is an organophosphorus compound with the formula C4H9)2C6H3Osub>3P. This white solid is a widely used stabilizer in polymers where it functions as a secondary antioxidant. It also reduces discoloration (yellowing) of plastics. The compound is a phosphite ester formed by the reaction of 2,4-di-tert-butylphenol with phosphorus trichloride. It is an approved food contact materials Food contact materials or food contacting substances (FCS) are materials that are intended to be in contact with food. These can be things that are quite obvious like a glass or a can for soft drinks as well as machinery in a food factory or a ... in the US.{{cite journal , last1=Markley , first1=Laura C. , last2=González Bonet , first2=Andrés M. , last3=Ogungbesan , first3=Adejoke , last4=Bandele , first4=Omari J. , last5=Bailey , first5=Allan B. , last6=Patton , first6=Geoffrey W. , title=Safety assessment for Tris(2,4-di-tert-butylphenyl) phosphite (Irgaf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyolefin
A polyolefin is a type of polymer with the general formula (CH2CHR)n where R is an alkyl group. They are usually derived from a small set of simple olefins (alkenes). Dominant in a commercial sense are polyethylene and polypropylene. More specialized polyolefins include Polyisobutene, polyisobutylene and polymethylpentene. They are all colorless or white oils or solids. Many copolymers are known, such as polybutene, which derives from a mixture of different butene isomers. The name of each polyolefin indicates the olefin from which it is prepared; for example, polyethylene is derived from ethylene, and polymethylpentene is derived from 4-methyl-1-pentene. Polyolefins are not olefins themselves because the double bond of each olefin monomer is opened in order to form the polymer. Monomers having more than one double bond such as butadiene and isoprene yield polymers that contain double bonds (polybutadiene and polyisoprene) and are usually not considered polyolefins. Polyolefins are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engineering Plastic
Engineering plastics are a group of plastic materials that have better mechanical or thermal properties than the more widely used commodity plastics (such as polystyrene, polyvinyl chloride, polypropylene and polyethylene). Engineering plastics are more expensive than standard plastics, therefore they are produced in lower quantities and tend to be used for smaller objects or low-volume applications (such as mechanical parts), rather than for bulk and high-volume ends (like containers and packaging). Engineering plastics have a higher heat resistance than standard plastics and are continuously usable at temperatures up to about . The term usually refers to thermoplastic materials rather than thermosetting ones. Examples of engineering plastics include polyamides (PA, nylons), used for skis and ski boots; polycarbonates (PC), used in motorcycle helmets and optical discs; and poly(methyl methacrylate) (PMMA, major brand names acrylic glass and plexiglass), used e.g. for taillight ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyurethane
Polyurethane (; often abbreviated PUR and PU) is a class of polymers composed of organic chemistry, organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane term does not refer to the single type of polymer but a group of polymers. Unlike polyethylene and polystyrene, polyurethanes can be produced from a wide range of starting materials resulting in various polymers within the same group. This chemical variety produces polyurethanes with different chemical structures leading to many List of polyurethane applications, different applications. These include rigid and flexible foams, and coatings, adhesives, Potting (electronics), electrical potting compounds, and fibers such as spandex and polyurethane laminate (PUL). Foams are the largest application accounting for 67% of all polyurethane produced in 2016. A polyurethane is typically produced by reacting a polymeric isocyanate with a polyol. Since a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
