(643e) Fiber Dissolution Using Naoh/Urea Solution

Cellulose dissolution is always an important and interesting research topic. Among the solvents for cellulose dissolution, NaOH/urea aqueous solution has recently attracted researchers' attention particularly owing to its environmental friendliness and cost effectiveness. Previous studies indicated that the chemical components, molecular structure and the crystallinity of cellulosic materials are key factors that affect the dissolution rate and dissolution degree. It was found that there are several abnormalities of this dissolution system comparing with regular polymer dissolution, for examples, the dissolution system favors cold temperature rather than high temperature and some high crystallinity celluloses have higher dissolution degree than low crystallinitity celluloses. However the underlying mechanisms of these phenomena have not been fully understood.

This study is dedicated to investigate the mechanism for the specific interaction between cellulose and NaOH/urea solvent system. The effects of temperature and solvent chemistry on the dissolution process are studied. The systematically study using celluloses with different molecular weights, crystalinities, particle sizes of the crystals will be reported. The regeneration process and the properties of regenerated celluloses from the solution at different conditions will also been reported.