Recent progress in regenerated cellulose-based fibers from alkali/urea system via spinning process

Cellulose as the most abundant renewable polymer displays great potential to substitute the petroleum-derived synthetic polymers. However, cellulose is difficult to be melted or dissolved, which greatly restricts its development and utilization. Herein, the "green" alkali/urea aqueous system for cellulose dissolution is briefly summarized by illustrating the dissolving mechanism. The comparison of cellulose fibers from different solvent is presented. In addition, the recent achievements for the efficient and "green" preparation of regenerated cellulose fibers from alkali/urea system are also summarized. By investigating the effects of experimental conditions and technical parameters on the structure and performance of regenerated cellulose fibers, the improved fiber mechanical properties and the decreased production costs are achieved. Moreover, the preparation and application of cellulose-based functional fibers from alkali/urea system are also reviewed, together with the urgent challenges and future development perspectives, which provide the novel approach for the high value-added development and utilization of cellulose fibers.