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2-Hydroxyethyl Terephthalic Acid
2-Hydroxyethyl terephthalic acid is an organic compound with the formula HOC2H4O2CC6H4CO2H. It is the monoester of terephthalic acid and ethylene glycol. The compound is a precursor to poly(ethylene terephthalate) (PET), a polymer that is produced on a large scale industrially. 2-Hydroxyethyl terephthalic acid is a colorless solid that is soluble in water and polar organic solvents. Near neutral pH, 2-hydroxyethyl terephthalic acid converts to 2-hydroxyethyl terephthalate, HOC2H4O2CC6H4CO2−. Occurrence and reactions 2-Hydroxyethyl terephthalic acid is an intermediate in both the formation and hydrolysis of PET. It is produced on a massive scale as the first intermediate in certain routes to PET. Specifically, it is produced in the course of the thermal condensation of terephthalic acid and ethylene glycol: :HOC2H4OH + HO2CC6H4CO2H → HOC2H4O2CC6H4CO2H + H2O Further dehydration of 2-hydroxyethyl terephthalic acid gives PET. It is also produced by the partial hydrolys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Living t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. They perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties. '' Nomenclature Etymology Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terephthalic Acid
Terephthalic acid is an organic compound with formula C6H4(CO2H)2. This white solid is a commodity chemical, used principally as a precursor to the polyester PET, used to make clothing and plastic bottles. Several million tonnes are produced annually. The common name is derived from the turpentine-producing tree ''Pistacia terebinthus'' and phthalic acid. History Terephthalic acid was first isolated (from turpentine) by the French chemist Amédée Cailliot (1805–1884) in 1846. Terephthalic acid became industrially important after World War II. Terephthalic acid was produced by oxidation of ''p''-xylene with dilute nitric acid. Air oxidation of ''p''-xylene gives ''p''-toluic acid, which resists further air-oxidation. Conversion of ''p''-toluic acid to methyl p-toluate (CH3C6H4CO2CH3) opens the way for further oxidation to monomethyl terephthalate, which is further esterified to dimethyl terephthalate. In 1955, Mid-Century Corporation and ICI announced the bromide-promoted oxida ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethylene Glycol
Ethylene glycol (IUPAC name: ethane-1,2-diol) is an organic compound (a vicinal diol) with the formula . It is mainly used for two purposes, as a raw material in the manufacture of polyester fibers and for antifreeze formulations. It is an odorless, colorless, flammable, viscous liquid. Ethylene glycol has a sweet taste, but it is toxic in high concentrations. Production Industrial routes Ethylene glycol is produced from ethylene (ethene), via the intermediate ethylene oxide. Ethylene oxide reacts with water to produce ethylene glycol according to the chemical equation: This reaction can be catalyzed by either acids or bases, or can occur at neutral pH under elevated temperatures. The highest yields of ethylene glycol occur at acidic or neutral pH with a large excess of water. Under these conditions, ethylene glycol yields of 90% can be achieved. The major byproducts are the oligomers diethylene glycol, triethylene glycol, and tetraethylene glycol. The separation of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly(ethylene Terephthalate)
Polyethylene terephthalate (or poly(ethylene terephthalate), PET, PETE, or the obsolete PETP or PET-P), is the most common thermoplastic polymer resin of the polyester family and is used in synthetic fibre, fibres for clothing, packaging, containers for liquids and foods, and thermoforming for manufacturing, and in combination with glass fibre for engineering resins. In 2016, annual production of PET was 56 million tons. The biggest application is in fibres (in excess of 60%), with bottle production accounting for about 30% of global demand. In the context of textile applications, PET is referred to by its common name, polyester, whereas the acronym ''PET'' is generally used in relation to packaging. Polyester makes up about 18% of world polymer production and is the fourth-most-produced polymer after polyethylene (PE), polypropylene (PP) and polyvinyl chloride (PVC). PET consists of repeating (C10H8O4) units. PET is commonly PET bottle recycling, recycled, and has the digit 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensation Reaction
In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a dehydration synthesis. However other molecules can also be lost, such as ammonia, ethanol, acetic acid and hydrogen sulfide. The addition of the two molecules typically proceeds in a step-wise fashion to the addition product, usually in equilibrium, and with loss of a water molecule (hence the name condensation). The reaction may otherwise involve the functional groups of the molecule, and is a versatile class of reactions that can occur in acidic or basic conditions or in the presence of a catalyst. This class of reactions is a vital part of life as it is essential to the formation of peptide bonds between amino acids and to the biosynthesis of fatty acids. Many variations of condensation reactions exist. Common examples include the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PETase
PETases are an esterase class of enzymes that catalyze the hydrolysis of polyethylene terephthalate (PET) plastic to monomeric mono-2-hydroxyethyl terephthalate (MHET). The idealized chemical reaction is (where n is the number of monomers in the polymer chain): :(ethylene terephthalate)n + H2O → (ethylene terephthalate)n-1 + MHET Trace amount of the PET breaks down to bis(2-hydroxyethyl) terephthalate (BHET). PETases can also break down PEF-plastic ( polyethylene-2,5-furandicarboxylate), which is a bioderived PET replacement, into the analogous . PETases can't catalyze the hydrolysis of aliphatic polyesters like polybutylene succinate or polylactic acid. Non-enzymatic natural degradation of PET will take hundreds of years, but PETases can degrade PET in matter of days. History The first PETase was discovered in 2016 from ''Ideonella sakaiensis'' strain 201-F6 bacteria found from sludge samples collected close to a Japanese PET bottle recycling site. Other types of PET degradi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Alcohols
A primary alcohol is an alcohol in which the hydroxy group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ... is bonded to a primary carbon atom. It can also be defined as a molecule containing a “–CH2OH” group. In contrast, a secondary alcohol has a formula “–CHROH” and a tertiary alcohol has a formula “–CR2OH”, where “R” indicates a carbon-containing group. Examples of primary alcohols include ethanol and n-Butanol, 1-butanol. Methanol is also generally regarded as a primary alcohol, including the 1911 edition of the Encyclopædia Britannica,. See also * Alcohol (chemistry), Alcohol (especially Nomenclature section for discussion on Secondary and Tertiary alcohols.) * Oxidation of primary alcohols to carboxylic acids References Primary alcohols, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
