Effective preparation of cellulose derivatives in a new simple cellulose solvent

Abstract

Cellulose with a degree of polymerization up to 650 can be dissolved in dimethyl sulfoxide containing 10 to 20% (w/v) tetrabutylammonium fluoride trihydrate without any pretreatment within 15 min at room temperature. The new solvent can be classified as a non-derivatizing one as concluded from 13C NMR measurements. The solvent can be used as reaction medium for the homogeneous functionalization of the polymer. Cellulose esters are prepared very effective by transesterification reactions. The functional groups are distributed in the order expected for a homogeneous conversion, i. e., a preferred reaction at the primary hydroxyl groups occurs. Moreover, carboxymethyl cellulose with a preferred functionalization at the primary hydroxyl groups and a non-statistic content of the different repeating units was accessible.