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Polypyrrole (PPy) is a type of organic polymer formed by polymerization of pyrrole. Polypyrroles are conducting polymers, related members being polythiophene, polyaniline, and polyacetylene.〔"Polypyrrole: a conducting polymer; its synthesis, properties and applications" ''Russ. Chem. Rev.'' 1997; vol. 66, p.443ff. (PDF )〕 The Nobel Prize in Chemistry was awarded in 2000 for work on conductive polymers including polypyrrole.〔A. G. MacDiarmid, "Synthetic metals: A novel role for organic polymers (Nobel Lecture)" ''Angew. Chem., Int. Ed.'' 2001; 40, 2581-2590. 〕 ==Synthesis== Some of the first examples of polypyrroles were reported in 1963 by Weiss and coworkers. These workers described the pyrolysis of tetraiodopyrrole to produce highly conductive materials.〔R. McNeill, R. Siudak, J. H. Wardlaw, D. E. Weiss "Electronic Conduction in PolymersI. The Chemical Structure of Polypyrrole" Aust. J. Chem. 1963, vol. 16, pp. 1056-75. 〕 Most commonly PPy is prepared by oxidation of pyrrole, which can be achieved using ferric chloride in methanol: :n C4H4NH + 2 FeCl3 → (C4H2NH)n + 2 FeCl2 + 2 HCl Polymerization is thought to occur via the formation of the pi-radical cation C4H4NH+. This electrophile attacks the C-2 carbon of an unoxidized molecule of pyrrole to give a dimeric cation (C4H4NH)2]++. The process repeats itself many times. Conductive forms of PPy are prepared by oxidation ("p-doping") of the polymer: :(C4H2NH)n + x FeCl3 → (C4H2NH)nClx + x FeCl2 The polymerization and p-doping can also be affected electrochemically. The resulting conductive polymer are peeled off of the anode. Cyclic voltammetry and chronocoulometry methods can be used for electrochemical synthesis of polypyrrole.〔Ahmad Sharifi-Viand, (Determination of fractal rough surface of polypyrrole film: AFM and electrochemical analysis ), Synthetic metals(Elsevier), 191: 104-112 (2014). 〕 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「Polypyrrole」の詳細全文を読む スポンサード リンク
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