翻訳と辞書
Words near each other
・ Carpathian Flysch Belt
・ Carpathian Foothills
・ Carosone
・ Carosue Dam Gold Mine
・ Carotene
・ Carotene (horse)
・ Carotene 7,8-desaturase
・ Carotene epsilon-monooxygenase
・ Carotenoid
・ Carotenoid 1,2-hydratase
・ Carotenoid isomerooxygenase
・ Carotenoid oxygenase
・ Carotenoid-9',10'-cleaving dioxygenase
・ Carotenosis
・ Carothers
Carothers equation
・ Carothers Parkway General Dentistry
・ Caroticotympanic
・ Caroticotympanic arteries
・ Caroticotympanic nerves
・ Carotid artery
・ Carotid artery dissection
・ Carotid artery stenosis
・ Carotid body
・ Carotid bruit
・ Carotid canal
・ Carotid Doppler machine
・ Carotid endarterectomy
・ Carotid groove
・ Carotid plexus


Dictionary Lists
翻訳と辞書 辞書検索 [ 開発暫定版 ]
スポンサード リンク

Carothers equation : ウィキペディア英語版
Carothers equation
In step-growth polymerization, the Carothers equation (or Carothers' equation) gives the degree of polymerization, ''X''n, for a given fractional monomer conversion, ''p''.
There are several versions of this equation, proposed by Wallace Carothers who invented nylon in 1935.
==Linear polymers: two monomers in equimolar quantities==
The simplest case refers to the formation of a strictly linear polymer by the reaction (usually by condensation) of two monomers in equimolar quantities. An example is the synthesis of nylon-6,6 whose formula is ()n
from one mole of hexamethylenediamine, H2N(CH2)6NH2, and one mole of adipic acid, HOOC-(CH2)4-COOH. For this case〔Cowie J.M.G. "Polymers: Chemistry & Physics of Modern Materials (2nd edition, Blackie 1991), p.29〕〔Rudin Alfred "The Elements of Polymer Science and Engineering", Academic Press 1982, p.171〕
:\bar_n=\frac
In this equation
:
*\bar_n is the number-average value of the degree of polymerization, equal to the average number of monomer units in a polymer molecule. For the example of nylon-6,6 \bar_n = 2n (n diamine units and n diacid units).
:
*p=\frac is the extent of reaction (or conversion to polymer), defined by
:
*N_0 is the number of molecules present initially as monomer
:
*N is the number of molecules present after time t. The total includes all degrees of polymerization: monomers, oligomers and polymers.
This equation shows that a high monomer conversion is required to achieve a high degree of polymerization. For example, a monomer conversion, ''p'', of 98% is required for \bar_n = 50, and ''p'' = 99% is required for \bar_n = 100.

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「Carothers 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.