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|Section2= |Section3= |Section7= }} Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colourless liquid, the methyl ester of methacrylic acid (MAA) is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA). ==Production and properties== The compound is manufactured by several methods, the principal one being the acetone cyanohydrin (ACH) route. ACH is produced by condensation of acetone and hydrogen cyanide. The cyanohydrin is hydrolyzed in the presence of sulfuric acid to a sulfate ester of the methacrylamide, Methanolysis of this ester gives ammonium bisulfate and MMA. Although widely used, the ACH route coproduces substantial amounts of ammonium sulfate. :(CH3)2CO + HCN → (CH3)2C(OH)CN :(CH3)2C(OH)CN + H2SO4 → (CH3)2C(OSO3H)C(O)NH2. In fact the sulfate ester of the amide is initially produced as an adduct with sulfuric acid ((CH3)2C(OSO3H)C(O)NH2. H2SO4), which is removed in a cracking step. The sulfate ester is then methanolyzed (reacted with methanol): :(CH3)2C(OSO3H)C(O)NH2 + CH3OH → CH2 =C(CH3)C(O)OCH3 + NH4HSO4 As indicated in the last reaction, each kilogram of methyl methacrylate produced yields 2.5 kg of ammonium hydrogen sulphate, Disposal of this salt is energy intensive. This technology affords more than 3 billion kilograms per year. The economics of the ACH route have been heavily optimized.〔Koichi Nagai, New developments in the production of methyl methacrylate, Applied Catalysis A: General 221 (2001) 367–377〕〔http://www.chemistryviews.org/details/news/2502791/New_Catalyst_for_Methyl_Methacrylate_Process.html〕 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「Methyl methacrylate」の詳細全文を読む スポンサード リンク
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