One-Step Activation and Surface Fatty Acylation of Cellulose Fibers in a Solvent-Free Condition

Abstract

Fatty acid cellulose esters with excellent water repellency and improved processability have gained a lot of attention in varied applications. In this study, a “green” synthetic route employing mechanochemical reaction methods was developed to prepare long-chain cellulose esters from cellulose fibers. Specifically, cellulose fibers were ball-milled to prepare activated cellulose particles; asymmetric mixed anhydrides from acetic anhydride and oleic acid were formed for improved esterification reactivity. Cellulose powder and mixed anhydride were mechanochemically reacted during ball-milling. The effects of the catalyst, ball-milling time, and reagent molar ratio were investigated. The results revealed that ball-milling was shown to be an effective approach to modifying the surface of cellulose powder with acetic–oleic mixed chains. The adding of a catalyst accelerated the reaction greatly. Increasing the ball-milling time and raising the mixed anhydride molar fractions promoted the esterification of cellu...