Man
Made Fibers
As a result of chemical processing of Cotton and
wood pulp cellulose is extracted. The fabric is thus made from these man made
cellulose fibers. Ex: Rayon , Acetate.
Fibers are made in a similar way by synthesizing
carbon, oxygen, hydrogen and other chemical elements into large, complex
molecular combinations or structures called polymers, which help in creating
man-made non-cellulose polymer fibers. Ex: Nylon, Polyester, and Acrylic.
Chemists successfully extracted Proteins from corn
and milk, which have been chemically processed to make man-made protein fibers.
But this has not achieved commercial success.
Rayon:
The two types of rayon that are being commercially produced are Viscose and
high wet-modulus.
Acetate:
This is primarily used for apparel. This consists of a cellulose compound
identified as acetylated cellulose a cellulose salt. The fiber is
thermoplastic, thus can be transformed into any desired shape by the
application of pressure or heat.
Nylon:
This fiber is thermoplastic, resilient, elastic and very strong and therefore
is used for a wide variety of apparel, home furnishings and industrial
products. This is a manufactured fiber in which carbon, oxygen, nitrogen, and
hydrogen are combined by chemical processes into compounds to form long chain
molecules, known as polyamides and are then formed into fibers.
Polyester:
These fibers are also thermoplastic, strong and hydrophobic (do not absorb
water well). They are also Used for a wide variety of apparel, home furnishings
and also industrial fabrics. This is another manufactured fiber in which the
carbon, oxygen and hydrogen are polymerized.
Conversion of Fiber to Yarn
In modern mills, most fiber processing operations
are performed by mechanical means. Bales of cotton and fleece of wool are
treated at the mill to remove various unwanted material such as twigs and
burrs. Wool must also be treated to remove suint or wool grease. Similarly silk
must be treated to remove sericin ( a gum from the cocoon ), and the very short
silk fibers or unwanted silk. Raw linen, the fiber of flax, is separated from
the impurities before delivery. Man made fibers rarely contain these waste
materials as they are produced by factory operations.
Natural Fibers
Everything comes from nature and thus fibers are
naturally available to mankind. The following fall under the classification of
natural fibers :
1. Vegetable fibers found in the cell walls of
plants, ex: cotton, linen,Jute
2. Animal fibers produced by animals or insects, ex: wool , Silk
3. Mineral Fibers mined from certain types of rocks ex: Asbestos
Vegetable Fibers
Cotton Fiber:
This grows in the seedpod of the cotton plant. Each fiber is a single,
elongated cell that is flat, twisted and ribbon like with a wide inner hollow.
Composition of the cell:
It is composed of 90% cellulose, about 6% moisture and remaining 45% consists
of natural impurities. A protective wax like coating covers the outer
surface of the fiber. This gives the fiber an adhesive quality.
Fabrics woven from the yarn spun from this fiber
are universally accepted for all types of apparel, home furnishings and
industrial applications. Major producers of this fiber are U.S..A, Russia,
China and India. Other small producers include Pakistan, Brazil, Turkey, Egypt,
Mexico, Iran and Sudan.
Linen Fiber:
This fiber is obtained from the stalk of the flax
plant. The composition of the fiber is about 70% cellulose, 30% Pectin, ash,
woody tissue and moisture. Linen has a smooth, straight and lustrous finish and
is widely used for apparel, home furnishings and upholstery, though it is more
brittle and less flexible than cotton. Largest producer of this fiber is the
Russia. Other large producers include Poland, Germany, Belgium and France.
Largest exporters are Northern Ireland and Belgium.
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