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Phthalic Anhydrides
Phthalic anhydride is the organic compound with the formula C6H4(CO)2O. It is the anhydride of phthalic acid. Phthalic anhydride is a principal commercial form of phthalic acid. It was the first anhydride of a dicarboxylic acid to be used commercially. This white solid is an important industrial chemical, especially for the large-scale production of plasticizers for plastics. In 2000, the worldwide production volume was estimated to be about 3 million tonnes per year. Synthesis and production Phthalic anhydride was first reported in 1836 by Auguste Laurent. Early procedures involved liquid-phase mercury-catalyzed oxidation of naphthalene. The modern industrial variant process instead uses vanadium pentoxide (V2O5) as the catalyst in a gas-phase reaction with naphthalene using molecular oxygen. The overall process involves oxidative cleavage of one of the rings and loss of two of the carbon atoms as carbon dioxide. An alternative process involves oxidation of the two meth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society (professional association) in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 34,000 in the UK and a further 8,000 abroad. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monochlorophenol
The monochlorophenols are chemical compounds consisting of phenol substituted with a Chlorine, chlorine atom. There are three isomers, 2-chlorophenol, 3-chlorophenol, and 4-chlorophenol. See also * Chlorophenol * Monobromophenol References {{reflist Chloroarenes Phenols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinizarine Green SS
Quinizarine Green SS, also called Solvent Green 3 is an anthraquinone derivative. It is a black powder that is soluble in polar organic solvents, but insoluble in water. It is used as a dye for adding greenish coloring to cosmetics and medications. It is used in some colored smoke formulations. According to X-ray crystallography, the anthroquinone portion of the molecule is planar. Both amine protons form hydrogen bonds to the carbonyls. This dye is a component in some smoke grenade Smoke grenades used at demonstrations in Paris, 2008 upBritish L83A1 Smoke Grenade manufactured in May 2008. This grenade has already been used. A smoke grenade is a canister-type grenade used as a signaling device, target or landing zone mark ...s, and questions have been raised about its toxicity. References {{reflist Solvent dyes Anthraquinone dyes Aromatic amines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthroquinone
Anthraquinone, also called anthracenedione or dioxoanthracene, is an aromatic organic compound with formula . Isomers include various quinone derivatives. The term anthraquinone however refers to the isomer, 9,10-anthraquinone (IUPAC: 9,10-dioxoanthracene) wherein the keto groups are located on the central ring. It is a building block of many dyes and is used in bleaching pulp for papermaking. It is a yellow, highly crystalline solid, poorly soluble in water but soluble in hot organic solvents. It is almost completely insoluble in ethanol near room temperature but 2.25 g will dissolve in 100 g of boiling ethanol. It is found in nature as the rare mineral hoelite. Synthesis There are several current industrial methods to produce 9,10-anthraquinone: # The oxidation of anthracene. Chromium(VI) is the typical oxidant. # The Friedel-Crafts reaction of benzene and phthalic anhydride in presence of AlCl3. o-Benzoylbenzoic acid is an intermediate. This reaction is useful for producing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyes
A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution and may require a mordant to improve the fastness of the dye on the fiber. There are two broad categories of dyes: natural and synthetic; Natural dyes are dyes extracted from plants, Insects, or minerals. The majority of natural dyes are vegetable dyes derived from plant sources such as roots, berries, bark, leaves, and wood, as well as other biological sources like fungi. Synthetic dyes are also referred to as "coal tar dyes" because they are derived from substances that, until recently, could only be extracted from coal tar. A synthetic dye consists of a chromophore and an auxochrome added to a benzene derivative. Both dyes and pigments are colored, because they absorb only some wavelengths of visible light. Dyes are usually soluble i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinoline Yellow SS
Quinoline Yellow SS is a bright yellow dye with green shade. It is insoluble in water, but soluble in nonpolar organic solvents. Quinoline yellow is representative of a large class of quinophthalone pigments. It is suggested that quinoline yellow exhibits excited-state intramolecular proton transfer (ESIPT) behavior and the behavior might be the cause of its decent photostability, by recent spectroscopic study. Synthesis and reactions As first described in 1878, the dye is prepared by the fusion of phthalic anhydride and quinaldine. The compound exists as a mixture of two tautomers. Using other anhydrides and other quinaldine derivatives other dyes in the quinophthalone family can be prepared. When sulfonated, it converts to a water-soluble derivative, Quinoline Yellow WS. Uses and safety Quinoline Yellow SS is used in spirit lacquers, polystyrene, polycarbonates, polyamides, acrylic resins, and to color hydrocarbon solvents. It is also used in externally applied drugs and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bis(2-ethylhexyl) Phthalate
Bis(2-ethylhexyl) phthalate (di-2-ethylhexyl phthalate, diethylhexyl phthalate, diisooctyl phthalate, DEHP; incorrectly — dioctyl phthalate, DIOP) is an organic compound with the formula C6H4(CO2C8H17)2. DEHP is the most common member of the class of phthalates, which are used as plasticizers. It is the diester of phthalic acid and the branched-chain 2-ethylhexanol. This colorless viscous liquid is soluble in oil, but not in water. Production Di(2-ethylhexyl) phthalate is produced commercially by the reaction of excess 2-ethylhexanol with phthalic anhydride in the presence of an acid catalyst such as sulfuric acid or ''para''-toluenesulfonic acid. It was first produced in commercial quantities in Japan around 1933 and in the United States in 1939. : As 2-ethylhexanol is produced as a racemic mixture, DEHP consists of the (''R'',''R'')- and (''S'',''S'')-diasteromers, and the '' meso''-isomer. : Use Due to its suitable properties and the low cost, DEHP is widely used as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcoholysis
In chemistry, solvolysis is a type of nucleophilic substitution (S1/S2) or elimination reaction, elimination where the nucleophile is a solvent molecule. Characteristic of S1 reactions, solvolysis of a chirality (chemistry), chiral reactant affords the racemate. Sometimes however, the stereochemical course is complicated by intimate ion pairs, whereby the leaving anion remains close to the carbocation, effectively shielding it from an attack by the nucleophile. Particularly fast reactions can occur by neighbour group participation, with nonclassical ions as intermediates or transition states. Examples For certain nucleophiles, solvolysis reactions are classified. Solvolysis involving water (molecule), water is called hydrolysis. Related terms are alcoholysis (Alcohol (chemistry), alcohols) and specifically methanolysis (methanol), acetolysis, ammonolysis (ammonia), and aminolysis (alkyl amines). Glycolysis is however an older term for the multistep conversion of glucose to pyruvat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phthalate Ester
Phthalates (, ), or phthalate esters, are esters of phthalic acid. They are mainly used as plasticizers, i.e., substances added to plastics to increase their flexibility, transparency, durability, and longevity. They are used primarily to soften polyvinyl chloride (PVC). Note that while phthalates are usually plasticizers, not all plasticizers are phthalates. The two terms are specific and unique and cannot be used interchangeably. Lower-molecular-weight phthalates, those derived from C3-C6 alcohols, are being gradually replaced in many products in the United States, Canada, and European Union over health concerns. They are being replaced by high-molecular-weight phthalates (those with more than six carbons in their backbone, which gives them increased permanency and durability), as well as alternative plasticizers not based on phthalic anhydride. In 2010, the market was still dominated by high-phthalate plasticizers; however, due to legal provisions and growing environmental a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
V2O5OxNaphth
V, or v, is the twenty-second and fifth-to-last letter in the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''vee'' (pronounced ), plural ''vees''. History The letter V ultimately comes from the Phoenician letter ''waw'' by way of U. See U for details. During the Late Middle Ages, two minuscule glyphs of U developed which were both used for sounds including and modern . The pointed form "v" was written at the beginning of a word, while a rounded form "u" was used in the middle or end, regardless of sound. So whereas "valour" and "excuse" appeared as in modern printing, "have" and "upon" were printed as "haue" and "vpon". The first distinction between the letters "u" and "v" is recorded in a Gothic script from 1386, where "v" preceded "u". By the mid-16th century, the "v" form was used to represent the consonant and "u" the vowel sound, giving us the modern letter V. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
