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|Section2= |Section3= |Section4= |Section5= |Section6= |Section7= |Section8= }} Ethylene oxide, properly called oxirane by IUPAC, is the organic compound with the formula . It is a cyclic ether. (A cyclic ether consists of an alkane with an oxygen atom bonded to two carbon atoms of the alkane, forming a ring.) Ethylene oxide is a colorless flammable gas at room temperature, with a faintly sweet odor; it is the simplest epoxide: a three-membered ring consisting of one oxygen atom and two carbon atoms. Because of its special molecular structure, ethylene oxide easily participates in addition reactions; e.g., opening its ring and thus easily polymerizing. Ethylene oxide is isomeric with acetaldehyde and with vinyl alcohol. Although it is a vital raw material with diverse applications, including the manufacture of products like polysorbate 20 and polyethylene glycol (PEG) that are often more effective and less toxic than alternative materials, ethylene oxide itself is a very hazardous substance. At room temperature it is a flammable, carcinogenic, mutagenic, irritating, and anaesthetic gas, with a misleadingly pleasant aroma. The chemical reactivity that is responsible for many of ethylene oxide's hazards has also made it a key industrial chemical. Although too dangerous for direct household use and generally unfamiliar to consumers, ethylene oxide is used industrially for making many consumer products as well as non-consumer chemicals and intermediates. Ethylene oxide is important or critical to the production of detergents, thickeners, solvents, plastics, and various organic chemicals such as ethylene glycol, ethanolamines, simple and complex glycols, polyglycol ethers and other compounds. As a poison gas that leaves no residue on items it contacts, pure ethylene oxide is a disinfectant that is widely used in hospitals and the medical equipment industry to replace steam in the sterilization of heat-sensitive tools and equipment, such as disposable plastic syringes. Ethylene oxide is industrially produced by direct oxidation of ethylene in the presence of silver catalyst. It is extremely flammable and explosive and is used as a main component of thermobaric weapons;〔〔 therefore, it is commonly handled and shipped as a refrigerated liquid.〔Rebsdat, Siegfried and Mayer, Dieter (2005) "Ethylene Oxide" in ''Ullmann's Encyclopedia of Industrial Chemistry''. Wiley-VCH, Weinheim. .〕 ==History== Ethylene oxide was first reported in 1859 by the French chemist Charles-Adolphe Wurtz, who prepared it by treating 2-chloroethanol with potassium hydroxide: :Cl–CH2CH2–OH + KOH → (CH2CH2)O + KCl + H2O Wurtz measured the boiling point of ethylene oxide as 13.5 °C, slightly higher than the present value, and discovered the ability of ethylene oxide to react with acids and salts of metals. Wurtz mistakenly assumed that ethylene oxide has the properties of an organic base. This misconception persisted until 1896 when Georg Bredig found that ethylene oxide is not an electrolyte.〔 That it differed from other ethers — particularly by its propensity to engage in addition reactions, which are typical of unsaturated compounds — had long been a matter of debate. The heterocyclic triangular structure of ethylene oxide was proposed by 1868 or earlier.〔Eugen F. von Gorup-Besanez, ed., ''Lehrbuch der organischen Chemie für den Unterricht auf Universitäten'' … (of Organic Chemistry for Instruction at Universities … ), 3rd ed. (Braunschweig, Germany: Friedrich Vieweg und Sohn, 1868), vol. 2, (p. 286 ). See also (p. 253 ) of the 1876 edition: Eugen F. von Gorup-Besanez, ed., ''Lehrbuch der organischen Chemie für den Unterricht auf Universitäten'' … , 5th ed. (Braunschweig, Germany: Friedrich Vieweg und Sohn, 1876), vol. 2.〕 Wurtz's 1859 synthesis long remained the only method of preparing ethylene oxide, despite numerous attempts, including by Wurtz himself, to produce ethylene oxide directly from ethylene. Only in 1931 did French chemist Theodore Lefort develop a method of direct oxidation of ethylene in the presence of silver catalyst.〔Lefort, T.E. (23 April 1935) "Process for the production of ethylene oxide". 〕 Since 1940, almost all industrial production of ethylene oxide has relied on this process. Sterilization by ethylene oxide for the preservation of spices was patented in 1938 by the American chemist Lloyd Hall. Ethylene oxide achieved industrial importance during World War I as a precursor to both the coolant ethylene glycol and the chemical weapon mustard gas. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ethylene oxide」の詳細全文を読む スポンサード リンク
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