Synthesis and properties ofO-2-[2-(2-methoxyethoxy)ethoxy]acetyl cellulose

Abstract

In this article, a series of O‐2‐[2‐(2‐methoxyethoxy)ethoxy]acetyl celluloses with different degree of substitution (DS) values was synthesized by a homogeneous reaction of cellulose with 2‐[2‐(2‐methoxyethoxy)ethoxy]acetyl chloride in a 10% (w/w) dimethylacetamide/lithium chloride solution, combined with pyridine as the acid acceptor. The total DS values of the derivatives in anhydroglucose units was determined by 1H and 13C NMR spectra, and ranged from 0.4 to 3.0, depending on the amount of acid chloride in the reaction. The effects of the total DS values and the O‐2‐[2‐(2‐methoxyethoxy)ethoxy]acetyl substituent distribution on the solubility of the derivatives were investigated. The lowest limit of the DS value for water‐soluble O‐2‐[2‐(2‐methoxyethoxy)ethoxy]acetyl cellulose was approximately 0.5, which is lower than that of methylcellulose. The amphiphilic derivatives with higher DS values than 1.7 exhibited a good solubility in both water and organic solvents, such as dimethyl sulfoxide, tetrahydrofuran, and chloroform. Sol‐gel transition in aqueous solution was observed for the amphiphilic derivatives with a higher DS value than 1.7; the precipitation temperature (Tp) decreased as the DS value increased, showing that the derivatives are highly temperature sensitive. The thermal properties of the fully substituted derivative were measured using polarized microscopy, DSC, and X‐ray diffraction; and are discussed in terms of phase transition of the sample derivatives. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 376–382, 2001

Partial substitution of cellulose by ring‐opening esterification of cyclic esters in a homogeneous system

“…Cellulose C3‐OH has no relation to the formation of a cellulose/LiCl/DMAc complex due to the intramolecular hydrogen bond with the O5 of the adjacent AHG unit 15. It has also been reported that the reactivity order for cellulose‐OH is C2 > C6 ≫ C3 in heterogeneous systems, while C6 > C2 ≫ C3 in a LiCl/DMAc system 16, 17. Moreover, many researchers have reported that bulky moieties are regioselectively introduced at the C6‐OH of cellulose 18–20.…”

Nanofiltration Membranes with Modified Active Layer Using Aromatic Polyamide Dendrimers

“…obtained by reacting 2-[2-(2-methoxyethoxy)ethoxy]acetic acid with thionyl chloride, was used to functionalize the amine-terminated NH 2 -Gn (n = 1-3) by amide bond formation. [ 17 ] Aramide dendrimers G1-G3 were then obtained in moderate yield after column chromatography. The structures of dendrimers G1-G3 have been characterized by 1 H NMR, 13 C NMR, MALDI-TOF mass spectrometry and gel permeation chromatography (GPC).…”