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Cyclododecatriene
Cyclododecatrienes are cyclic trienes with the formula C12H18. Four isomers are known for 1,5,9-cyclododecatriene. The ''trans'',''trans'',''cis''-isomer is a precursor in the production of nylon-12. : Production The ''trans'',''trans'',''cis''-isomer is obtained by cyclotrimerization of butadiene catalyzed by a mixture of titanium tetrachloride and an organoaluminium co-catalyst. Production capacity in 1995 was 8000 tons. : As aforementioned, titanium catalysts predominantly produce the important ''cis'',''trans'',''trans''- isomer. The all-''trans'' isomer is, however, the product from nickel- and chromium-catalyzed trimerization reactions. The yield of cyclododecatriene through these methods is often greater than 80%. The principal side products are the dimers and oligomers of butadiene. Properties All of the isomers of 1,5,9-cyclododecatriene are colorless, possess typical terpene-like odors, and have low melting points. The all-''trans'' isomer melts at 34 °C while the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marl Chemical Park
Marl Chemical Park (german: Chemiepark Marl) is an industrial park in Marl, North Rhine-Westphalia, Germany. It is the third largest industrial cluster in Germany and among the largest chemical production facilities in Europe. The site occupies over 6 square kilometers, hosts 100 chemical plants, employs 10,000 people, and produces 4 million metric tons of chemicals annually. 18 companies are based in the Park, including primary tenant Evonik Industries AG, which also owns and operates the infrastructure through its subsidiary Infracor GmbH. Originally named Chemische Werke Hüls, the complex was built in 1938 by a consortium led by IG Farben to produce synthetic rubber and other war materials for the Third Reich. By 1942 over 5000 workers' families had relocated into new housing which transformed Marl into a company town. At the height of World War II, the Germans also used slave laborers and prisoners of war at the plant. Allied bombing heavily damaged the site in mid-1943 al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evonik Industries
Evonik Industries AG is a stock-listed German specialty chemicals company headquartered in Essen, North Rhine-Westphalia, Germany. It is the second largest chemicals company in Germany, and one of the largest specialty chemicals companies in the world. It is predominantly owned by the RAG Foundation and was founded on 12 September 2007 as a result of restructuring of the mining and technology group RAG Aktiengesellschaft, RAG. Evonik Industries united the business areas of chemicals, energy and real estate of RAG, while mining operations continue to be carried out by RAG. Since then, the energy and real estate business areas have been divested, with no share being held in the former and a minority share still being held in the latter. Its specialty chemicals business generates around 80% of sales in areas in which it holds leading market positions. Evonik Industries employs about 37,000 people and carries out activities in more than 100 countries. The operating activitie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butadiene
1,3-Butadiene () is the organic compound with the formula (CH2=CH)2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a precursor to synthetic rubber. The molecule can be viewed as the union of two vinyl groups. It is the simplest conjugated diene. Although butadiene breaks down quickly in the atmosphere, it is nevertheless found in ambient air in urban and suburban areas as a consequence of its constant emission from motor vehicles. The name butadiene can also refer to the isomer, 1,2-butadiene, which is a cumulated diene with structure H2C=C=CH−CH3. This allene has no industrial significance. History In 1863, the French chemist E. Caventou isolated butadiene from the pyrolysis of amyl alcohol. This hydrocarbon was identified as butadiene in 1886, after Henry Edward Armstrong isolated it from among the pyrolysis products of petroleum. In 1910, the Russian chemist Sergei Lebedev polymerized butadiene and obtained a material wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laurolactam
Laurolactam is an organic compound from the group of macrocyclic lactams. Laurolactam is mainly used as a monomer in engineering plastics, such as nylon-12 and copolyamides.T. Schiffer, G. Oenbrink: ''Cyclododecanol, Cyclododecanone, and Laurolactam.'' In: ''Ullmann's Encyclopedia of Industrial Chemistry.'' Wiley-VCH, Weinheim 2002, . Synthesis Although a derivative of 12-aminododecanoic acid, it is made from cyclododecatriene. The triene is hydrogenated to the saturated alkane, cyclododecane. For the production of laurolactam, cyclododecane is oxidized with air or oxygen in the presence of boric acid and transition metal salts (e.g. cobalt(II) acetate), obtaining a mixtureH.-J. Arpe: ''Industrielle Organische Chemie.'' 6., vollst. überarb. Aufl., Wiley-VCH Verlag, Weinheim, 2007, . of cyclododecanol and cyclododecanone. This mixture is quantitatively dehydrogenated on a copper contact catalyst to cyclododecanone and this reacted with hydroxylamine to cyclododecanone oxime. The o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dodecanedioic Acid
Dodecanedioic acid (DDDA) is a dicarboxylic acid with the formula . A white solid, the compound finds a variety of applications ranging from polymers to materials. The unbranched compound is the most commonly encountered C12 dicarboxylic acid. Production DDDA has traditionally been produced from butadiene using a multi-step chemical process. Butadiene is first converted to cyclododecatriene through cyclotrimerization. The triene is then hydrogenated to cyclododecane. Autoxidation by air in the presence of boric acid gives a mixture of cyclodecanol and the cyclododecanone. In the final step, this mixture oxidized to the diacid using nitric acid. An alternative route involves ozonolysis of cyclododecene. : Biological process Paraffin wax can be converted into DDDA on a laboratory scale with a special strain of ''Candida tropicalis'' yeast in a multi-step process. Renewable plant-oil feedstocks sourced from switchgrass could also be used to produce DDDA. Uses DDDA os used i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigma-Aldrich
Sigma-Aldrich (formally MilliporeSigma) is an American chemical, life science, and biotechnology company that is owned by the German chemical conglomerate Merck Group. Sigma-Aldrich was created in 1975 by the merger of Sigma Chemical Company and Aldrich Chemical Company. It grew through various acquisitions until it had over 9,600 employees and was listed on the Fortune 1000. The company is headquartered in St. Louis and has operations in approximately 40 countries. In 2015, the German chemical conglomerate Merck Group acquired Sigma-Aldrich for $17 billion. The company is currently a part of Merck's life science business and in combination with Merck's earlier acquired Millipore Corporation, Millipore, operates as MilliporeSigma. History Sigma Chemical Company of St. Louis and Aldrich Chemical Company of Milwaukee were both American specialty chemical companies when they merged in August 1975. The company grew throughout the 1980s and 1990s, with significant expansion in fac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boric Acid
Boric acid, more specifically orthoboric acid, is a compound of boron, oxygen, and hydrogen with formula . It may also be called hydrogen borate or boracic acid. It is usually encountered as colorless crystals or a white powder, that dissolves in water, and occurs in nature as the mineral sassolite. It is a weak acid that yields various borate anions and salts, and can react with alcohols to form borate esters. Boric acid is often used as an antiseptic, insecticide, flame retardant, neutron absorber, or precursor to other boron compounds. The term "boric acid" is also used generically for any oxoacid of boron, such as metaboric acid and tetraboric acid . History Orthoboric acid was first prepared by Wilhelm Homberg (1652–1715) from borax, by the action of mineral acids, and was given the name ("sedative salt of Homberg"). However boric acid and borates have been used since the time of the ancient Greeks for cleaning, preserving food, and other activities. Molecular a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nylon 12
Nylon 12 is a nylon polymer with the formula CH2)11C(O)NHsub>n. It is made from ω-aminolauric acid or laurolactam monomers that each have 12 carbons, hence the name ‘Nylon 12’. It is one of several nylon polymers. Synthesis Nylon 12 can be produced through two routes. The first being polycondensation of ω-aminolauric acid, a bifunctional monomer with one amine and one carboxylic acid group. n H2N(CH2)11CO2H → CH2)11CONHsub>n + n H2O The second route is ring-opening polymerization of laurolactam at 260-300˚C. Ring opening can be carried out by cationic or anionic initiators, although cationic initiators have not been used commercially due to the product being less stable and oxidized relatively quickly in comparison to those produced by activated anionic polymerization (monomer casting). Ring-opening polymerization is the preferred route for commercial production. :n CH2)11CONH → CH2)11CONHsub>n Properties Nylon 12 exhibits properties between short chain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beckmann Rearrangement
The Beckmann rearrangement, named after the German chemist Ernst Otto Beckmann (1853–1923), is a rearrangement of an oxime functional group to substituted amides. The rearrangement has also been successfully performed on haloimines and nitrones. Cyclic oximes and haloimines yield lactams. The Beckmann rearrangement is often catalyzed by acid; however, other reagents have been known to promote the rearrangement. These include tosyl chloride, thionyl chloride, phosphorus pentachloride, phosphorus pentoxide, triethylamine, sodium hydroxide, trimethylsilyl iodide among others. The Beckmann fragmentation is another reaction that often competes with the rearrangement, though careful selection of promoting reagent and solvent conditions can favor the formation of one over the other, sometimes giving almost exclusively one product. The rearrangement occurs stereospecifically for ketoximes and N-chloro/N-fluoro imines, with the migrating group being anti-periplanar to the leaving gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxime
In organic chemistry, an oxime is a organic compound belonging to the imines, with the general formula , where R is an organic side-chain and R’ may be hydrogen, forming an aldoxime, or another organic group, forming a ketoxime. O-substituted oximes form a closely related family of compounds. Amidoximes are oximes of amides () with general structure . Oximes are usually generated by the reaction of hydroxylamine with aldehydes () or ketones (). The term ''oxime'' dates back to the 19th century, a combination of the words ''oxygen'' and ''imine''. Structure and properties If the two side-chains on the central carbon are different from each other—either an aldoxime, or a ketoxime with two different "R" groups—the oxime can often have two different geometric stereoisomeric forms according to the ''E''/''Z'' configuration. An older terminology of ''syn'' and ''anti'' was used to identify especially aldoximes according to whether the R group was closer or further from the hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydrogenation
In chemistry, dehydrogenation is a chemical reaction that involves the removal of hydrogen, usually from an organic molecule. It is the reverse of hydrogenation. Dehydrogenation is important, both as a useful reaction and a serious problem. At its simplest, it is useful way of converting alkanes, which are relatively inert and thus low-valued, to olefins, which are reactive and thus more valuable. Alkenes are precursors to aldehydes (), alcohols (), polymers, and aromatics. As a problematic reaction, the fouling and inactivation of many catalysts arises via coking, which is the dehydrogenative polymerization of organic substrates. Enzymes that catalyze dehydrogenation are called dehydrogenases. Heterogeneous catalytic routes Styrene Dehydrogenation processes are used extensively to produce aromatics in the petrochemical industry. Such processes are highly endothermic and require temperatures of 500 °C and above. Dehydrogenation also converts saturated fats to unsatura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclododecanone
Cyclododecanone is an organic compound with the formula (CH2)11CO. It is a cyclic ketone that exists as a white solid at room temperature. It is produced by the oxidation of cyclododecane via cyclododecanol. Cyclododecanone is mainly consumed as a precursor to 1,12-dodecanedioic acid and laurolactam, which are precursors to certain specialized nylons. Small amounts are also converted to cyclohexadecanone Cyclohexadecanone is an organic compound with the formula (CH2)15CO. It is a cyclic ketone, which is a minor component of the musk scent of the civet. Several related derivatives are also important in the fragrance industry, especially those wi ..., which is used in some fragrances.Johannes Panten and Horst Surburg "Flavors and Fragrances, 2. Aliphatic Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2015, Wiley-VCH, Weinheim. References Perfume ingredients Macrocycles Mammalian pheromones Cycloalkanones {{Ketone-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
