Processing of Textile Fibers Textile Fibers Fibers Fiber
Processing of Textile Fibers
Textile Fibers
Fibers • Fiber is a class of materials that are continuous filaments, similar to lengths of thread. • One common definition of a fiber requires that its length be at least 100 times its diameter.
Natural Fibers
• Natural fibers include those produced by plants, animals, and geological processes. They are biodegradable over time. They can be classified according to their origin: • Vegetable fibers are generally based on arrangements of cellulose, often with lignin: examples include cotton, hemp, jute, flax, ramie, and sisal. Plant fibers are employed in the manufacture of paper and textile (cloth), • Wood fiber distinguished from vegetable fiber, is from tree sources. • Animal fibers consist largely of particular proteins. Instances are spider silk, sinew, catgut, wool and hair, fur such as sheepskin, rabbit, mink, fox, beaver, etc. • Mineral fibers comprise asbestos. Asbestos is the only naturally occurring long mineral fiber.
Synthetic Fibers
Cellulose fibers • Cellulose fibers are a subset of man-made fibers, regenerated from natural cellulose. The cellulose comes from various sources. Modal is made from beech trees, bamboo fiber is a cellulose fiber made from bamboo, seacell is made from seaweed, etc.
Mineral fibers • Fiberglass, made from specific glass, and optical fiber, made from purified natural quartz, silica fiber, made from sodium silicate (water glass). • Metallic fibers can be drawn from ductile metals such as copper, gold or silver. • Carbon fibers are often based on oxidized and carbonized polymers, but the end product is almost pure carbon.
Polymer fibers • Polymer fibers are a subset of man-made fibers, which are based on synthetic chemicals (often from petrochemical sources). These fibers are made from: – – – polyamide nylon, PET or PBT polyester phenol-formaldehyde (PF) polyvinyl alcohol fiber (PVA) polyvinyl chloride fiber (PVC) polyolefins (PP and PE) acrylic polyesters, pure polyester PAN fibers. Aromatic polyamids (aramids) polyethylene (PE), eventually with extremely long chains Elastomers polyurethane fiber
PET
Acetal Polyoxymethylene (POM), also known as acetal. polyacetal, and polyformaldehyde, is an engineering thermoplastic
ABS
PTFE
PVF is also used as whiteboard surface material (Coating)
PEEK Polyether ketone
Definition of Textile Terms • Denier is a unit of measure for the linear mass density of fibers. It is defined as the mass in grams per 9, 000 meters. 1 denier= 1 gram per 9 000 meters= 0. 05 grams per 450 meters (1/20 of above)= 0. 111 milligrams per meter
Tenacity: The tensile strength of fiber is usually expressed in terms of tenacity. Tenactiy is the customary measure of strength of a fiber or yarn. Tenacity is defined as the strength per unit size number, such as the denier. Tenacity is thus a function of the density of the fiber as well as its tensile strength.
• Crimp is the waviness of the fibers, a measure of the difference between the length of the unstraightened and that of the straightened fiber.
Fiber Spinning Fibers are made from polymers by a process called Spinning. 1. Melt Spinning 2. Dry Spinning 3. Wet Spinning
Melt Spinning
Lumps are removed
Wet Spinning
Non solvent precipitates polymer in the form of fine filaments.
Dry Spinning
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