Sulfonation of HwBKP by Sulfur Trioxide Pyridine Complex and Preparation of Anionic Cellulose Beads Using the Same

Abstract

To expand the applications of cellulose beads, sulfonated cellulose beads were prepared by chemically modifying HwBKP fibers with sulfur trioxide pyridine complex (STP), dissolving in tetraethylammonium hydroxide (TEAOH)/urea solvent, and dropping into acetic acid solution. The effect of the amount of STP added on the properties of sulfonated cellulose solution and cellulose beads was investigated. It was observed that the sulfonated cellulose beads exhibited anionic surface charge in a fairly wide pH range, and the degree of substitution of sulfonic acid groups and the zeta potential of the cellulose beads could be controlled by adjusting the amount of added STP. In addition, as the amount of STP added increased, the crystallinity of the cellulose decreased, the viscosity and surface tension of the sulfonated cellulose/TEAOH/urea solution decreased, and the size of the cellulose beads increased.