Premium
Characteristics of carboxymethyl cellulose synthesized in two‐phase medium C 6 H 6 C 2 H 5 OH. I. Distribution of substituent groups in the anhydroglucose unit
Author(s) -
Cheng Fa,
Li Guifeng,
Feng Jianxin,
Zhang Jingwu
Publication year - 1996
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/(sici)1097-4628(19960906)61:10<1831::aid-app25>3.0.co;2-3
Subject(s) - substituent , crystallinity , carboxymethyl cellulose , chemistry , benzene , cellulose , ethanol , crystallography , stereochemistry , organic chemistry , sodium
Carboxymethyl cellulose was synthesized in two‐phase medium containing benzene, ethanol, and water. The distribution of substitution of hydroxyl group attached to C k Carbons ( k = 2, 3, and 6) in an anhydroglucose unit (AGU) was determined by 1 H‐NMR method. It showed that the sequence of distribution of carboxymethyl group of the products in AGU was C 6 > C 2 > C 3 ; and when degree of substitution (DS) was low to 1.0, the approximate value of C 2 : C 3 : C 6 was 1.45: 1: 2.15. When DS was higher than 1.0 and increased, the distribution of substitution tends to identical. Through analysis of X‐ray diffraction and calculation of crystallinity and interplanar distance of CMC, the principle of distribution of the substituent had been explained. The influence of benzene on distribution of substituent of CMC was also investigated. It was found that distribution of substituent of CMC prepared in medium benzene‐ethanol at C 6 position was higher than that prepared in ethanol. © 1996 John Wiley & Sons, Inc.