Any substance, natural
or manufactured, the small component, hair like in nature with a high length to
wide ratio and with suitable characteristics for being processed into yarn to
fabric called Textile Fiber.
What are the Properties of Textile Fiber?
Primary Properties- High length to width ratio, Tenacity, Flexibility, Spinning quality (cohesiveness), Uniformity
Secondary Properties- Elastic recovery, Density, Lusture, Color,
Moisture regain, Resiliency, Physical Shape etc.
Besides Properties of Textile are four types-
1.
Physical Properties- Length, Fineness, Crimp, Maturity, Softness,
Lusture, Rupture, Density, Elongation, Flexibility etc.
2.
Chemical Properties- Chemical composition, Effects of Acid, Effects of
Alkali, Effects of Organic Solvents, Effects of Insects, Effects of
micro-organism etc.
3.
Mechanical Properties- Solubility in Aqueous Salt, Solubility in Organic
Salt etc.
4.
Structural Properties- Fine Structure, Micro Structure, X-Sectional view,
Longitudinal view etc
What is the
Classification of Textile Fiber?
Classifications: Textile fibers can be
classified as two groups- 1. Natural Fibers & 2. Man-Made Fibers.
These are again divided
in many groups which are given in below picture-
Fig:-Textile Fibers Classification
What are the tests usually used for Fiber
Identification?
Fiber Identification Tests-
1. Burning Test
2. Light Microscopy Test
3. Chemical Solubility Test (Acetic Acid, Acetone, Sodium Hypochlorite used)
2. Light Microscopy Test
3. Chemical Solubility Test (Acetic Acid, Acetone, Sodium Hypochlorite used)
What is Cotton Fiber?
Cotton:
Cotton is a natural, cellulosic, seed & mono-cellular staple fiber.
Cotton fiber is the King of all fiber. It is
a soft, fluffy staple fiber that grows in a boll, or protective
capsule, around the seeds of cotton plants of the genus Gossypium. The
fiber is almost pure cellulose. Under natural conditions, the cotton bolls
will tend to increase the dispersion of the seeds.
What is Cotton Polymer?
The cotton polymer is a
linear, cellulose polymer. The repeating unit in the cotton polymer is
cellobiose which consists of two glucose units. The
cotton polymer consists of about 5000 cellubiose units, i.e. degree of
polymerization. The most important
chemical groupings on the cotton polymer are hydroxyl groups (OH) and methyl groups
(CH2OH).
What are the Physical & Chemical Properties of
Cotton Fiber?
Physical Properties
|
Chemical
Properties
|
Length: 0.5'' to 2.75''
Lusture: High
Tenacity(Strength): Dry- 3-5 g/d , Wet- 3.3-6.0
g/d
Moisture regains-7.1-8.5 %, Strength increase when
wet.
Mercerized: conditioned- 8.5–10.3%
Density- 1.54-1.56 g/cm³
|
Effect of acid: damage
Effects of Alkali: no harmful effects
Organic Solvents: high resistance to most
Microorganism- Mildew and rot-producing bacteria
damage fibers.
Insects-Silverfish damage fibers |
What are the types of Cotton Fiber?
Types of Cotton Fiber-
·
Egyptian Cotton
·
Sea Island Cotton
·
Pima Cotton
·
Asiatic Cotton
·
American Upland Cotton
·
Canton Cotton
·
French Terry Cotton
·
Organic Cotton
·
Bamboo Cotton etc.
What
are the uses of Cotton Fiber?
Uses of Cotton:
Cotton is used to
make a number of textile products. These include terrycloth for highly
absorbent bath towels and robes; denim for blue
jeans; cambric, popularly used in the manufacture of blue work shirts
(from which we get the term "blue-collar"); and corduroy,
seersucker and cotton twill. Socks, and most T-shirts are
made from cotton. Bed sheets often are made from cotton. Cotton also is used to
make yarn used in crochet and knitting Fabric also can be made from
recycled or recovered cotton that otherwise would be thrown away during the
spinning, weaving, or cutting process. While many fabrics are made completely
of cotton, some materials blend cotton with other fibers, including rayon
and synthetic fibers such as polyester. It can either be used in
knitted or woven fabrics, as it can be blended with elastine to make a
stretcher thread for knitted fabrics, and apparel such as stretch jeans.
Write Short Note on Jute Fiber.
Jute:
According to classification, jute is the bast fiber.
The Jute strand is a bundle of individual fiber, held together by gums, Waxes,
and lignin. The cross section of fiber is polygonal in shape with sharply
defined angles. Cell is thick, the lumen is large.
Chemical Composition:
Cellulose 65.2%
Hemi-Cellulose 22.2%
Lignin 10.8%
Water
soluble matter 1.5%
Fats
and Wax 0.3%
Physical Properties
|
Chemical Properties
|
Length (fiber)- 150 to 300 cm (5-12 ft)
Length to width ratio- 90 : 1
Moisture regains- 13.75% and absorbs
30-40 ml.of water of its dry weight.
Strength- Tendency dry 3.5- 5 g/d.
Wet strength is lower than dry strength.
Elasticity- Breaking extension-
1.8, Recovery (y.) is very low.
|
Effects of bleaches: Not affects
by oxidizing and reducing bleaches.
Effect of acid and alkali: Easily
damaged by acids resistance to alkalis.
Dye ability: Easily dyed but
light and wash fastness is poor.
Biological Properties: Scoured Jute
has good to excellent resistant to micro-organism and insects.
|
What are defects of Jute Fiber?
Defects of Jute:
- Specky
Jute: If the jute fibers are not rotted and washed properly the barks
adhere to the fibers causing them speck.
- Rooty
fiber: If the plants are allow to stay in water for long time, then the
root ends are rooted causing Rooty fiber.
- Knots
fibers: Having knot in the fiber or sticky together. Difficult to separate
the fiber from the steam.
Write
Short note on Wool Fiber.
Wool Fiber:
According to
classification, Wool is Natural Protein/Animal Hairy fiber which is collected
from hair of Sheep or Lamb. The wool fiber is
made of two or three layers- on the outer layer of scales called cuticle, middle
area called the cortex and the central area called medulla.
Keratin 33%
Dust 26%
Suit 28%
Fat 12%
Mineral matter 1%
Macro
Structure of Wool:
Length- 5 cm
to 35 cm
Diameter- 14 m
and coarse- 45 m
Length to width
ratio- Fine short- 2500:1 & Long coarse- 75:1
Color- Off
white, light cream.
Physical Properties
|
Chemical Properties
|
Moisture
regain- 13 – 16%, very absorbent, decrease
strength when wet.
Strength:
Tenacity, dry = 1.35 g/d,wet = dry *.69
Elasticity:
Breaking extension 69%,Recovery 5%
Hand
Feel: Very soft.
|
Effect
of acids: Fairly stable in acid.
Effect
of alkali: Destroy and dissolved.
Bleaching:
Bleaching powder is harmful.
Heat:
Burn, poor conductivity.
Dye
ability- Easy to dye by acid dye
|
What
are types of Wool Fiber?
Types:
Two
type of Wool fibers are found-
1. Woolen
fiber = Cording
2. Worsted
fiber = Cording + Combing.
Write
Short notes on Silk Fiber.
Silk:
Silk
is Smooth, soft, lustrous & resilient fiber. Silk is called the queen of
all fibers. Silk is filament by the caterpillar of various butter flies. Silkworms spin cocoons in filaments. Silk is very fine, regular filament.
Chemical Composition
Silk
or fibroin 62.5 to 67%
Silk
gum or sericin 22 to 25%
Water 10 to 11%
Salts 1 to 1.75%
The Macro Structure of Silk:
Length- 600
meter long. Average-300 meter.
Diameter- 12
m to 30 m
Length to
width ratio- 2000 : 1
Color- bright
yellow.
Physical Properties
|
Chemical Properties
|
Moisture Regain- 11%
Strength- Tenacity- dries 4.3 g/d,
Strength decrease very lightly when wet. Wet = dry * 0.92.
Elasticity- Breaking extension-
23.4%
Resiliency- Moderate.
|
Effect of Acid- Degraded by acid.
Effect of Alkali- More resistance
by wool.
Heat- Poor conduct ivy
Dye- Ability to dye need lower temperature
than any other natural fiber. Give brighter shade with direct, acid, basic
and vat dyes.
|
Write
Short note on Viscose Fiber.
Viscose:
Viscose is a manufactured regenerated
cellulose fiber. It is made from Cotton linter or Wool pulp which is chemically
converted into a soluble compound which is purified by dissolving in a solution
of Ammonia, Copper Sulphate and Caustic Soda. It is then dissolved and forced
through a spinneret to produce filaments which are chemically solidified resulting
in synthetic fibers of nearly pure cellulose.
Physical Properties
|
Chemical Properties
|
It is a linear
cellulose polymer, similar to that of cotton.
Viscose is
fine, regular filament or staple fiber.
Diameter- 12 m
to 22 m.
Moisture
regain- 11%
Strength:
Tenacity- 1.8 to 2.9 g/d.
|
Effect of acid and alkali- Easily
damaged by acid, concentrated alkali will course swelling and reduced
strength.
Bleaches: It can withstand both
oxidizing and reducing bleaches.
Dye ability- Better affinity for
dyes than cotton, can be dyed with Direct dye, Reactive dye or Vat dyes.
Flammability- Burn rapidly.
Sunlight and heat- Will undergo
degradation when exposed to sunlight, it loses strength.
|
Write Short note on Polyester
Fiber.
Polyester:
Polyester is a manmade synthetic fiber. It is
the most commonly used polyester apparel filaments which are usually composed
of polyethylene terephthalate polymers. Compared with nylon, polyesters are
rather heavy fibers. For this reason, polyester textile materials are
manufactured as light weight or thin fabrics.
Physical Properties
|
Chemical Properties
|
Polyester are a medium weight fiber
with a density of 1.39 g/cm
The fiber diameter of polyester
filament or staple fibers ranges from 12 cm to 25 cm
Length to width ration- 2000 : 1
Tenacity 4.5 to 5.5 g/d.
The polyester filaments are hard and
stiff to handle. Their breaking extension is 30%.
Moisture Regain- 0 to 0.4%
Hydrophobic.
Thermal Properties- Sensitive to heat
|
Effect of acid- Polyester is very
resistant to acid. They are dyed with disperse dye anti acidic medium.
Bleaches- Normally polyester textile
materials do not need to bleach
Dye ability- Very difficult for dye
molecule to penetrate into the polyester fibers. Only relatively small
molecules of disperse dyes are used to dye or print polyester fiber at high
temperature pressure.
|
What are the uses of Polyester
fiber?
Polyester fiber in use:
Wrinkle free
appearance, ease of care, resist wrinkling, no or little require ironing, easy
to dry, blend with wool, cotton, rayon, easy to maintain due to strength and
durability.
Write
note on Acrylic Fiber.
Acrylic
The acrylic
fibers are manmade, synthetic Polymer based, Poly acrylonitrile. They are
divided into two types-
1. Polyacrylonitrile fibers- generally
referred to as the acrylic fibers.
2. Modified polyacrylonitrile fibers-
generally referred to as the modocrylic fibers.
Commercial
Names:
Acrylon, Creslan, Zefran,
Courtelle, Verel.
Physical Properties
|
Chemical Properties
|
Diameter- 15 m to 25
m
Length width ration- 200 : 1
Color- Dull
Strength- Tenacity- 2.5 – 3 g/d. The
strength of acrylic fiber is fair to strong. In wet condition, they loss
their tenacity.
Moisture Regain- 1.24%,
Acrylic fiber are hydrophobic
|
Effect of
Acids- The acrylic fibers are resistance to acid. Acids are used for stain
and spot removal.
Alkali-
Resistance to weak alkali but affected by boiling strong detergent, washing
soda, eventually lead to discoloration, yellowing.
Dye- Acrylic
and modocrylic fibers are most commonly dyed and printed basic and disperse
dyes
|
Write note on Elastomeric Fiber.
Elastomeric Fibers (Spandex):
The word elastomeric was coined from elosic and
polymer to imply an elastic fiber. Chemically the elastomeric's are
polyurethane based fibers, shoes polymers are characterized by urethane group.
Spandex is the generic term used in
the USA for elastic fibers.
Physical Properties
|
Chemical Properties
|
Tenacity- tenacity unaffected whether
wet or dry.
Elastic- Plastic nature-
Extremely elastic Moisture regain-
Thermal Properties- Thermoplastic,
sensitive to heat excessive application of heat may result in a complete loss
of the elastic property.
|
Effect of Acid- Resistant to
acid.
Alkali- Effect by alkali, seen at
a yellowing of the white or a dulling of the colored elostomaric textile
materials.
Dye- Difficult to dye as it is
hydrophobic.
|
What
are characteristics of a good textile fiber?
Essential
characteristics:
A)
Length-
should not be less than 5mm
B) Staple Length- Short Staple
Length=2‘’, Medium Staple Length= 2‘’-4‘’, Long Staple Length=4’’
C) Strength and related properties
D) Flexibility
E) Cohesiveness.
Desirable
characteristics:
a) Fineness
b) Resiliency (Resistance to compression
fleering or torsion.
c) Uniformity
d) Porosity
e) Luster
f) Commercial availability.
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