A review on raw materials, commercial production and properties of lyocell fiber

Abstract

As one of the regenerated cellulosic fibers, viscose fiber has the largest output. However, the wastes produced in the manufacturing process are difficult to eliminate, which restricts the development of viscose fiber. Lyocell fiber is claimed as “green and eco-friendly fiber” with a good application prospect in the 21st century. The preparation of lyocell fiber is based on the cellulosic non-derivative solution system, i.e., N-methylmorpholine-N-oxide system which is nontoxic and recyclable. In this review, firstly, the demands of dissolving pulp properties for regenerated-cellulosic fiber (RCF), especially for lyocell fiber, were introduced in detail. Next, the whole manufacturing processes including pretreatment, preparation of spinning dope, spinning, posttreatment and efficient solvent recovery technologies were reviewed emphatically. Then, the properties and structural characteristics of lyocell fiber were illustrated. At last, some suggestions were proposed for lyocell fiber development in China.

Keywords

• Lyocell fibers
• N-methyl morpholine-N-oxide (NMMO)/H2O solution
• Spinning dope
• Dissolving pulp