Module 8 Lyocell Fiber PDF
Document Details
Uploaded by CrispVigor5348
Daffodil International University
Tags
Summary
This document provides an overview of Lyocell fiber, including its production methods, properties, and applications. It details the steps involved in manufacturing the fiber and highlights its unique characteristics. The document also includes comparisons to other fibers and their uses.
Full Transcript
LYOCELL FIBER Module 8 Content Introduction Chemistry of Fiber Manufacture Fiber Production Method Physical Properties Chemical Properties End Uses 2 Introduction » Lyocell is a new generatio...
LYOCELL FIBER Module 8 Content Introduction Chemistry of Fiber Manufacture Fiber Production Method Physical Properties Chemical Properties End Uses 2 Introduction » Lyocell is a new generation cellulosic fiber. » Fiber is made by solvent spinning i.e. dissolving and spinning without formation of a derivative. » Although direct solvent N-‐methylmorpholine-‐N-‐ oxide (NMMO) for cellulose was discovered in 1939, commercial production of Lyocell fiber started in 1988 by Courtaulds. » Global production close to 0.1m tons. 4 Viscose Vs. Lyocell 5 Chemistry of Lyocell Fiber 6 Lyocell Fiber Production 7 Lyocell Fiber Production » The wood (Eucalyptus, Oak etc.) pulp is shredded and mixed with dilute aqueous NMMO to penetrate the pulp fully. » Excess water is removed and the solution is heated under vacuum at 90-‐120oC. 8 After filtration of the spinning solution, fibers are formed by spinning into an air gap and then coagulating 9 in a water/NMMO bath. Lyocell Fiber Production » Fibers are washed and dried. » The wash liquor is purified and concentrated to recover the solvent. » NMMO is non-‐toxic and recycled within the process to generate minimum effluent. » Fibers are crimped and made in tow, staple or filament forms. 10 Physical Properties » Similar to viscose fiber but exhibits enhanced properties in terms of softness, drapability and dimensional stability. » Higher absorbency than cotton (MR, 11%) and quick release property. 14 Physical Properties » Strongest cellulosic fiber at dry and wet states. » Higher crystalline areas and orientation. » Can be made fibrillated or non-‐fibrillated. 15 Physical Properties 16 Chemical Properties » Better alkali resistance than viscose. » Better dyeability than cotton and viscose. » Susceptible to damage by mildew and silverfish. 17 End Uses » Apparel, home textiles and technical textiles. » Soft, luxurious men and women dresses. » Undergarments, hosiery and sportswear. 18 Thank You 20
