Properties of Cellulosic Material after Cationization in Different Solvents

Fibers resulting from pulping of wood are negatively charged by nature. Both the cellulose and hemicelluloses contribute to the anionicity. The negative charge of cellulosic material can be reversed with the same reagent commonly used for the cationization of starch. In this study, a bleached Kraft pulp was cationized in systems with different water-miscible organic solvents. Replacing 90% of the water with isopropanol and particularly with tetrahydrofuran yielded higher degrees of substitution and increased reaction efficiency. The degree of substitution depends on the concentration of the cationization reagent in water; partially replacing water with tetrahydrofuran can simulate a higher concentration while maintaining supramolecular properties, such as crystallinity and polymer chain integrity.