Uploaded by Yasir Khan

TEXTILE FIBER

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Textile Fiber Definition [An
Introduction]
Fiber is the first elementary raw material of textile manufacturing. To understand the whole textile manufacturing
process, it is essential to have a good knowledge about textile fiber definition.
There are two types of textile fibers: it is either natural or man-made, in form of staple or filaments. The types of textile
fiber determine their uses. Natural fibers are those fibers that are directly produces at nature, usually at plants, animals
or minerals.
Man-made synthetic fibers or artificial fibers which are usually manufactured from solutions of natural polymer
(cellulose, milk protein) or derivatives of natural polymer. Textile fibers should exhibit some specific properties which is
discussed in this content below.
Textile Fiber Definition
Textile fiber is a class of materials that are natural or manufactured can takes only tensile force not compression and
spun into yarn by twisted to-gather or also converting into fabric (non-woven) direct from fiber. If two fibers are twisted
to-gather is stronger than both individual without increasing its tenacity.
Fiber is continuous filament or is in discrete piece (staple). It is the smallest visible substance which is extremely thin in
relation to its width at least 500 times longer than its lateral dimension.
Types of textile fiber
There are two types of fibers:
1. Natural fiber
2. Man-made fiber
Natural fiber
Natural fibers are of three types:
1. Vegetable, Example: Cotton, Kapok, Coir (They are from Seed); Jute, Flax, Ramie (Baste); Abaca, Sisal, Henequn (They
are from leaf)
2. Animal, Example: Wool, Silk, Hair
3. Mineral, Example: Asbestos
Man-made fiber
These fibers are basically two types:
1. Regenerated, Example: Viscose, Lyocell, Modal, Cupro, Acetate, Tri-acetate, Alginate, Rubber, Casein, Protein
2. Synthetic, Example: Polyester, Nylon, Polyolefin, Polyvinyl acrylic, Elastane
3. Others: Glass, Carbon, Aramid, Metallic
Properties of Textile Fibers
There are several properties necessary for a polymeric material to make an adequate and appropriate fiber to
certain end uses. A fiber has to the following physical and chemical properties to meet some specific requirements
and these are:
 Fiber length
 Length to width ratio (Slenderness ratio)
 Tensile properties (Strength/Elongation)
 Elasticity
 Flexibility
 Elastic recovery from strain
 Cohesiveness
 Wet-ability
Dye-ability
 Density
 Comfort to human skin
 Resiliency
 Toughness
 Work of rupture
 Fiber friction
 Uniformity
 Crimp
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Fineness (MIC)
Color/Luster
Maturity ratio
High abrasion resistance
Chemical resistance
Textile Fiber Structure
Textile fibers are a class of solid organic polymers. This distinguishes them from other polymers by their physical
properties and geometric dimensions. But a few exception exists. This tem can’t be applicable for a few specialty
fibers like glass, asbestos etc. as they are based on inorganic substances.
Fiber can be easily identifiable. It is extremely long with respect to width, flexible and has high anisotropic physical
properties. But the only thing that differs fiber from the other polymers is their molecular structure. This molecular
structures decide the physical and chemical properties of fibers.
Levels of molecular structure
For the ease of perception, let’s consider three levels of molecular structure. Each level relates to certain aspects of
fiber behavior and properties.
The Organo-chemical Structure
>It defines the structure of repeating units in the base polymer.
>Also, it describes the nature of polymeric link.
>It is directly related to chemical properties, dyeability, moisture absorption, swelling characteristics and indirectly all
the physical properties.
The Macro-molecular structure
>It entitles the family of polymer molecules.
>Chain length, chain length distribution, chain stiffness, molecular size and molecular shape, all these parameters are
characterized by this structure.
The Super-molecular Structure
>Describes the arrangement of the polymer chains.
>Polymer orientation, crystallinity and fibrillar structure all these may be described by this structure.
In general, the textile fibers useful for textile applications are semi-crystalline and irreversibly oriented polymer. The
fibers have highly oriented molecular chains in some region where they are closely packed and near arranged. This
regions are named as crystalline region.
The physical properties of fibers are strongly influenced by degree of orientation or the degree of crystallinity.
The textile fiber has some regions where the molecular chains are not well oriented, tending to a random coil
configuration. These regions are referred to as amorphous region.
Various identifiable aggregates of polymer chains are found in case of natural fibers. These are often referred to as
micelles, fibrils, micro-fibrils etc.
Fiber Polymer System
Molecular segment is the basic unit of the textile fiber. This is called monomer. It is repeated to form a long chain or
macro-molecule. This is called polymer.
From two or more different monomers, formation of polymer can also be achieved. This is called co-polymer. To make
up a co-polymer, there is no definite regularity in the order of monomers.
Some fibers contain additional monomers. They are not a part of the polymer chain rather they are incorporated to
improve certain properties like dye affinity. These are grafted on the polymer chain as side group.
Cotton
The word cotton comes from Arabic word “Katan”. It is called the king of fibers just only because of the characteristics of
cotton. Cotton is the backbone of world’s textile market and it is also one of the most important and widely produced
agricultural and industrial crops in the world.
Cotton is grown is about 80 different countries. The most important producers are China, USA, India, Pakistan, Uzbekistan,
Turkey, Australia, Brazil, Argentina, and Syria. In this article we will discuss about the characteristics of cotton, types, physical
and chemical properties of cotton.
Characteristics of Cotton
Comfortable
Light weight
Non-elastic
Good draping quality
Feels soft
Super absorbent
Color retention capacity is good
Dry cleanable
Machine wash is possible
Great strength
Good cooling properties
Dries fast
Extremely shiny
Moisture absorption is very good
Very durable
Wet fibers are more resistant
Morphological structure
Cotton contains 95% cellulose. High grade, soft material with super absorbent quality- all these qualities are
extremely suitable for cotton.
Cotton is of different colors based on its origin. Cotton fiber length varies between 10 to 65 mm. American cotton
has white color whereas Egyptian and Chinese cotton has yellowish and red-yellowish color respectively.
Under microscope the fiber appears to beRibbon like
Kidney-shaped cross-section
Natural convulation of longitudinal view
Having two ends
Twisted in a spiral, tightly and regularly wrapped in high end fiber
With sanforization and mercerization process, the properties of cotton can be improved.
Morphological structure of cotton
Structural view of cotton
Polymeric structure of cotton
Cotton is a cellulosic fiber.80-90% cellulose is in cotton but oil, wax, protein, pectin and some coloring content
are also present. The polymer chain of cotton cellulose is linear.
It is a polymeric sugar of polysaccharide made up of 4000-9000 repeating cellobiose unit, which consists of two
glucose units connected to each other by 8-ether linkages.
The number of repeating unit of a polymer chain is called Degree of Polymerization (DP).
If 5000 repeating unit stay in a polymer chain then its Degree of Polymerization is 5000.
Macro structure of cotton
Grading & Classification of Cotton
The word Grading means the rating of cotton according to quality parameter of cotton. Cotton is classified by grading and it is
done according to length, fineness, strength, color, lusture and impurities. This division is done by different way according to
the production land.
Different grading systems
Properties of different cotton fibers
with spinning limit
General Physical & Chemical Properties of Cotton fiber
Fiber Length: Varies from 10-65 mm
Fiber Strength: Strength is varied 24-32 gm/tex
Fineness: The value varies 3-6
Maturity ratio: varies from 0.7-0.9
Color: Light yellow or brown
Moisture Content: 8.5%
Gravity: 1.48 – 1.51 g/cm3
Effects of Acids: Cotton fibers are weakened by cold weak dilute acids and degraded by strong acids.
Effects of Alkali: Unaffected or undamaged by alkaline solution
Types of Cotton yarns
 100% Cotton
These yarn has 100% cotton fibers. Garments containing 100% cotton yarn has ability to absorb sweat
immediately. It has cooling properties. So, this is used in hot weather extensively. But blends of cotton is cheap
than this. For maintaining high quality, 100% cotton is used to make garments or apparels.
 CVC
CVC stands for chief value cotton. A blended yarn having more percentage of cotton as compared to that of polyester is
called CVC yarn. For example: Cotton: Polyester 70: 30. Pricing of CVC is still too high.
 PC
Yarn produced by blending of cotton and polyester fibers. The maximum part of these yarns are polyester. The yarn
contains more than 50% of polyester. The rest part is cotton.
 TC
TC stands for Terelyne – Cotton. This is also made by blending of cotton and terelyne fibers. But in this case, the higher
amount used is polyester fibers and the rest portion is cotton fibers. TC yarn is used for making apparels most of the time.
This provides the soft and cool feel of cotton to the user.
Identification of cotton fiber
There are different tests which could be used for the identification of the cotton fiber. It is suggested to combine at least
two or more different methods to reach an acceptable and reliable conclusion in practice.
 Feeling test: Unresponsive, smooth and a soft hand to human skin, feels good against skin.
 Burning test: The reaction of fibers to heat from an open flame is a useful guide in identification of fibers. Non melt,
burn. Smell like paper burning. The smell of cotton burning is like of paper burning because paper is also a cellulosic
material.
Some technical tests are required for detailed identification
Microscopic identification
Chemical test
Coloring with dyestuffs
Solubility test: Cotton is easily dissolved by H2SO4
Staining
End use
Apparel
Home textile to Industrial textiles
Different Types of Cotton
Cotton is, by far, the most important textile fiber. There are different types of cotton fibers according to their staple
length and plant varieties. With the plant varieties, their quality also varies. To produce top quality product, we need
optimum quality cotton fibers.
Cotton consists of cellulose, a polymer of glucose. Cellulose is the basic building material of all types of vegetation and
many different plants are sources of cellulose fibers.
How we get cotton?
Cotton comes from the seed pod of plants in the Gossypium family cultivated in a number of subtropical climates. The
fibers grow out of the seeds in the closed pod. In the initial phase, they form long, thin-walled cells filled with protoplasm.
Later, as the growth in length ends, the cell walls increase in thickness as rings of cellulose are deposited on the inner
surface of the cell wall. When the pod or boll bursts, the cotton fibers, whose function is to aid seed transport in the wind,
dry out.
Once the remaining protoplasm has evaporated, the cotton bolls are harvested mechanically and the fibers removed from
the seeds by a process called ginning.
This must be carefully controlled to avoid over-cutting of the fibers. Cotton ‘linters’, the short lint hairs not removed from
the seeds by ginning, are also an important source of pure cellulose. Pressing the residual seeds gives cotton seed oil.
Types of cotton
In different parts of the world, many cotton fiber is grown with wide range growing conditions. As a result, there
are many grades of cotton fibers around the world. They are of various quality that vary widely with their
characteristics and properties.
It is a quite difficult job to assess the quality of cotton. It requires great skill and experience. Quality of cotton is
directly related with staple length and its characteristics which is generally quoted to refer any cotton.
Staple length is an assessment of fiber with respect to its technically most important length. In case of cotton,
staple length corresponds very closely with the most frequent length of the fibers when measured in a
straightened condition.
Commercial Types of Cotton
Commercial cotton may be classified broadly into three categories. Here they are:
 Staple length 1-1 ½ inch (26-65 mm): Includes the fine, lustrous fibers which forms the top quality cotton. The fibers
are generally of 10 -15 microns diameter and are of 1.1-1.8 dtex (0.99-1.62 den).
Sea Island, Egyptian, American pima are in this category. These are high category cotton. These cottons are difficult to
grow. Their supply are comparatively low.
 Staple length ½ – 1 5/16 inch (12-33mm): This includes medium strength, medium luster cotton. This form the
bulk of the world crop. These fibers are generally of 12-17 micron diameter and are of 1.4-2.2 dtex (1.26-1.98
den)
American upland and some Peruvian types fall into this category.
 Staple length 3/8 – 1 inch (9-26mm): This includes coarse and low grade fibers. They are low in strength and have
little or no luster. They are generally of 13-22 microns diameter. They are of 1.5-2.9 dtex (1.26-1.98 den)
Many of Asiatic, Indian and some Peruvian cottons fall in this category.
Types of Cotton depending on cotton plant varaites
According to plant varieties, there are 4 types of Cotton.
Gossypium hirsutum (Upland cotton)
Most widely this type of cotton is produced. 90% of the world’s cotton production is from this category. Cotton
from Central America and the Caribbean Sea Island accounts for this category. These are exported to every
location throughout the world. They are characterized by short-staple fiber that grows in any climate.
For making a quality fabric that all can afford, Upland is perfect. Especially in the US, this type of cotton mostly
plants. Or you can say, 95% of fibers grow in American soil.
Gossypium Hirsutum (Acala cotton)
San Joaquin Valley Acala, the cotton type only produced by California. Among all of the upland cotton, this type is the
highest quality cotton. This type of cotton gets benefits from the climate of San Joaquin Valley.
Acala cotton gets an extended growing period that increases yield. As a result, we get a finer product. This type of cotton
is a bit costlier than American Upland cotton. This is due to its growing requirements.
Gossypium barbadense (Pima Cotton)
This type of cotton accounts for 8% of the world’s cotton production. These are more expensive than the previous one. This
type of cotton consists of extra-long staple fiber. Textiles become softer and lustrous with this type of cotton.
South American cotton is from this category, they are exported throughout the world. Pima kind of cotton is from this
category. Producers from China and India produce this cotton.
So, what’s the benefit of using this extra-long staple fiber? It makes the fabric strong that makes it resistant to fraying,
fading, wrinkling, and pilling.
Gossypium herbaceum (Egyptian cotton)
This type of cotton grows in longer bushes that can be considered as tree. This accounts for 2% of the
world’s condition.
As like as Pima cotton, this type of Egyptian cotton is from extra-long staple fiber. This quality makes it also
soft, supple, and vibrant in performance. So what is the difference between Egyptian cotton and Pima
cotton?
The main difference is in the cultivation process of cotton. Egyptian cotton is grown at hot and dry climate
beside Neil River in Egypt. This type of cotton is exceptionally quality full.
Gossypium arboretum
This type of cotton is from Arabia and Africa. This accounts for not more than 2% of the world’s cotton cultivation.
To Wrap Up!
Cotton and Viscose contain pure cellulose among all fibers. Other natural fibers containing cellulose, also contain some
other constitutional materials. Although cotton and viscose are almost pure cellulose, they have quite different physical
properties because of their distinctive morphologies and molecular arrangements.
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