翻訳と辞書 Words near each other ・ Mayotte Magnus ・ Mayotte national football team ・ Mayotte national rugby union team ・ Mayotte Rugby Committee ・ Mayotte scops owl ・ Mayotte sunbird ・ Mayotte white-eye ・ Mayotte's 1st constituency ・ Mayoux ・ Mayovka ・ Mayovka (disambiguation) ・ Mayovka, Kaliningrad Oblast ・ Mayow Park ・ Mayoworth, Wyoming ・ Mayoyao, Ifugao ・ Mayo–Lewis equation ・ Maypan coconut palm ・ Maypearl High School ・ Maypearl Independent School District ・ Maypearl, Texas ・ Maypo ・ Maypole ・ Maypole (disambiguation) ・ Maypole Airfield ・ Maypole Dairy Products ・ Maypole, Birmingham ・ Maypole, Isles of Scilly ・ Mayport Ferry ・ Mayport, Florida ・ Mayport, Pennsylvania Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Mayo–Lewis equation ： ウィキペディア英語版 Mayo–Lewis equation The Mayo–Lewis equation or copolymer equation in polymer chemistry describes the distribution of monomers in a copolymer:〔''Copolymerization. I. A Basis for Comparing the Behavior of Monomers in Copolymerization; The Copolymerization of Styrene and Methyl Methacrylate'' Frank R. Mayo and Frederick M. Lewis J. Am. Chem. Soc.; 1944; 66(9) pp 1594 - 1601; 〕 It is named for Frank R. Mayo and Frederick M. Lewis. Taking into consideration a monomer mix of two components $M\_1\backslash ,$ and $M\_2\backslash ,$ and the four different reactions that can take place at the reactive chain end terminating in either monomer ($M^$ *\,) with their reaction rate constants $k\backslash ,$: :$M\_1^$ * + M_1 \xrightarrow} M_1M_2^ * \, :$M\_2^$ * + M_2 \xrightarrow} M_2M_1^ * \, and with reactivity ratios defined as: :$r\_1\; =\; \backslash frac\}\; \backslash ,$ :$r\_2\; =\; \backslash frac\}\; \backslash ,$ the copolymer equation is given as: :$\backslash frac\; =\backslash frac$ with the concentration of the components given in square brackets. The equation gives the copolymer composition at any instant during the polymerization. ==Limiting cases== From this equation several special cases can be derived: * $r\_1\; =\; r\_2\; >>\; 1\; \backslash ,$ with both reactivity ratios very high the two monomers have no inclination to react to each other except with themselves leading to a mixture of two homopolymers. * $r\_1\; =\; r\_2\; >\; 1\; \backslash ,$ with both ratios larger than 1, homopolymerization of component M_1 is favored but in the event of a crosspolymerization by M_2 the chain-end will continue as such giving rise to block copolymer * $r\_1\; =\; r\_2\; \backslash approx\; 1\; \backslash ,$ with both ratios around 1, monomer 1 will react as fast with another monomer 1 or monomer 2 and a random copolymer results. * $r\_1\; =\; r\_2\; \backslash approx\; 0\; \backslash ,$ with both values approaching 0 the monomers are unable to react in homopolymerization and the result is an alternating polymer * $r\_1\; >>\; 1\; >>\; r\_2\; \backslash ,$ In the initial stage of the copolymerization monomer 1 is incorporated faster and the copolymer is rich in monomer 1. When this monomer gets depleted, more monomer 2 segments are added. This is called composition drift. An example is maleic anhydride and stilbene, with reactivity ratio: * Maleic anhydride ($r\_1\backslash ,$ = 0.08) & cis-stilbene ($r\_2\; ,$ = 0.07) * Maleic anhydride ($r\_1\backslash ,$ = 0.03) & trans-stilbene ($r\_2\; ,$ = 0.03) Neither of these compounds homopolymerize and instead they react together to give exclusively alternating copolymer. Another form of the equation is: $F\_1=1-F\_2=\backslash frac\backslash ,$ where $F\backslash ,$ stands the mole fraction of each monomer in the copolymer: $F\_1\; =\; 1\; -\; F\_2\; =\; \backslash frac\; \backslash ,$ and $f\backslash ,$ the mole fraction of each monomer in the feed: $f\_1\; =\; 1\; -\; f\_2\; =\; \backslash frac\; \backslash ,$ When the copolymer composition has the same composition as the feed, this composition is called the ''azeotrope''. 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「Mayo–Lewis equation」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.