New solvents and functional materials prepared from cellulose solutions in alkali/urea aqueous system

Cellulose, the most abundant renewable polysaccharide on earth, has safe, biocompatible, hydrophilic and biodegradable natures, and is one of the best candidates for food packing and other functional materials. However, cellulose is hard to dissolve in most common solvents, which limited its development and application. In this paper, the quick dissolution of cellulose in NaOH/urea, NaOH/thiourea and LiOH/urea aqueous systems at the low temperature, as well as cellulose-based functional materials including fibers, films, membranes, microspheres, hydrogels and cellulose derivatives prepared via "green" process has been summarized. This review aims at highlighting on the recent researches and developments dealing with cellulose in our laboratory. About 84 literatures have been cited to describe the new aqueous cellulose solvents and functional materials and to discuss their wide applications in food packaging, separation technology, textile, and biomedicine and biology fields. (C) 2010 Elsevier Ltd. All rights reserved.