To become a textile fiber it
should have some properties or characteristics. Because textile fibers must be spun into a yarn or made
into a material by
interlacing, or interlooping in an
exceedingly sort of machines
including weaving, knitting, braiding, felting, bonding, etc. So we are able to define textile fiber as, a fiber
that has the power to
be processed into yarn which may further
be woven or knitted by certain interlacing methods is termed a textile
fiber. ( Govt jobs in
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In this article i'll discuss
different properties/characteristics of textile fiber and within the time unit i've got given different testing methods of those properties
Physical Properties of Textile Fibers:
Length and length uniformity:
Length of staple fiber is one
amongst the foremost important
characteristics. Generally a
extended average fiber length is to be preferred because it
confers variety of benefits. Because its
processing is relatively easy
from short length fiber. Besides, more even yarns is produced from them because there are less fiber ends in an exceedingly given length of
yarn and also a better strength
yarn is produced from
them for the identical level
of twist.
Moisture regain:
The amount of moisture (water) present in an exceedingly textile sample is brought up either by its regain
or its moisture content. These two terms are often confused with one another. Moisture regain is
expressed because the percentage
of water in an exceedingly sample
compared to its oven dry weight, also brought up as its bone dry weight. Moisture content is
expressed as a percentage of the
overall weight of the sample. the quality test method ASTM D2495-07 is most ordinarily employed within the textile industry to live the regain and moisture
content. The test could be a simple
one and may be easily
performed. A sample of fiber is collected and weighed, before being oven dried
at 105°C until it maintains a
continuing weight. The difference between the first mass before drying and therefore the oven dried mass
is calculated as a percentage, and is denoted either as moisture content or
moisture regain. Moisture regain and moisture content is measured using the subsequent equations.
W
R= ---------------- x 100 ------------------------------
(1)
D
W
C = ---------------- x 100
--------------------------------- (2)
D + W
Where,
R is the moisture regain
C is the moisture content
W is the weight of water
D is the oven dry weight
Trash content:
The presence of undesirable material within the fiber is taken into account to
be trash. Other synonyms include contamination and nonlint matter. it's comprised of fragments of
leaves, stalks, grasses, seeds, and dust. It also includes feathers; pieces of
plastic, rugs, and cloths; foreign fibrous material aside from the specified fiber (like
polyester or jute in cotton); and immature fibers. The immature fibers of the identical desired fiber are considered to be trash
as they're not
wanted within the final
product. A Shirley analyzer is
employed to see trash
content within the fibrous
tuft. It comprises a pair of rollers for gripped feeding into a sawtooth
beater, rotating at a high surface speed.
Cross-sectional shape of the
fiber:
Shape affects the physical and mechanical
properties of textile fiber. There are many properties which are changed
by the form of the
fiber’s cross section, like flexural rigidity, fabric softness, drape, crispness,
and stiffness. Different natural fibers have differing types of shapes, while the form of
artificial fibers depends upon the form of the spinneret from which they're extruded, as shown in
Figure. Like silk it's a
triangular cross section. Cotton fibers are kidney shaped. Wool fibers are
round or oval in shape.
Fiber color:
The color of the fiber is a very important aspect in relation to aesthetic sense and
dye shade. Every fiber type has its particular color regarding its natural or
synthetic origin. In natural fibers, cotton is found as white to yellowish in
color, wool
fiber has whitish to blackish color grades,
silk fiber is found during a lustrous
white color, and jute fiber is brown. Regenerated rayon fibers are transparent
in color unless dulled by pigments. In synthetic fibers, acrylic ones are white
to off-white, nylon ones are off-white, polyester ones are white, para-aramid
ones are dull yellowish, and carbon ones are black. Some fibers may be decolored to introduce new
colors by the dying process, while other fibers have a permanent color which
can’t be removed, as within the case
of Kevlar and carbon fibers.
Fiber fineness:
Fineness is one in all the most
important aspects of fiber characteristics and explains
cross-sectional thickness. A fine fiber may be wont to spin
fine yarns. because the linear
density of yarn decreases, the
quantity of fibers also decreases by yarn diameter. The presence or
absence of one fiber
shows longitudinal unevenness and variation in diameter. The decrease of fiber
diameter will increase the
quantity of fibers during
a cross section of yarn and hence better yarn evenness may be achieved.
Fiber fineness has great influence on the
properties of yarn and fabric. The evenness of the yarn is improved by the utilization of fine
fibers. additionally, fine
fibers need less twist and have less stiffness than coarser fibers. the rise in fiber surface thanks to a decrease in fiber
diameter contributes to a cohesion of fibers to realize the
identical strength with less twist than coarser fibers. These
characteristics contribute to the hand feel of the products developed from
them.
Fiber crimp:
The waviness during a fiber is
understood as crimp. it's measured because the number of crimps or
waves per unit length or the share increase within the extent of the fiber on
removal of the crimp. Crimps also govern the capacity of fibers to cohere under
light pressure. The bi-component structure of wool increases the crimp in it.
Cotton incorporates a low
crimp. Crimp allows the scattering of
sunshine thanks to its
wavy structure and provides a dull appearance on developed products. Synthetic
fibers are lustrous in structure, which
might be reduced by the introduction of crimps in them. Crimps
increase the thickness and enhance the bulky aspect of products.
Mechanical Properties of Textile Fiber
Fiber strength:
Strength of any material comes from the load it supports
at break and is thus a measure of its limiting load bearing capacity. Normally
strength of a textile fiber is measured in tension when the fiber is loaded
along its long axis and is designated as durability.
The strength and elongation of a cotton
fiber may be measured
by one fiber or by the
bundle method. The bundle fiber strength may be measured using an ASTM standard test procedure that employs
a nerve tissue tensile
testing machine. These machines are commercially available in pendulum
and machine mechanisms.
A fiber sample is conditioned as per the quality conditioning procedure.
Tenacity:
Tenacity is that the measure of the breaking strength of a textile
fiber. it's also
defined as ultimate breaking strength and is that the maximum force a fiber can bear without breakage.
The tenacity value for individual fibers is that the value of load applied at breakage. the precise stress is that the ratio of load to
linear density and is measured in units of g/denier, cN/tex, and MPa.
Blending is that the easiest
method to get synergistic
effects of two different materials. within the textile industry the blending of a fiber may be a common practice to get the specified functional and aesthetic properties.
Blends may be identified
either qualitatively or quantitatively. Furthermore, the testing methods for
the identification of fibers during
a blend may be technical
or nontechnical.
The nontechnical tests include the sensation test or the burning
test; these tests are for qualitative assessment.
Maturity
ratio:
The maturity of the cotton fiber is analyzed
using the ASTM standard test procedure by employing polarized light or
the hydroxide swelling
technique. an answer of
18% concentration of hydroxide is employed to swell the cotton
fibers by soaking them. The fibers are then laid parallel on the sheet glass and covered with
glass and viewed at a magnification of 400× to differentiate between immature and mature fibers. The
mature fibers swell to become almost round in cross-sectional shape. This
method isn't considered
acceptable for commercial testing thanks
to the poor precision of the results between different
laboratories.
Chemical composition:
The chemical composition of fibers depends on
their origin. Natural fibers obtained from plants are made from cellulosic structures like
cotton, jute, and hemp fibers. The fibers obtained from animals are composed of
amino acids like wool and silk. Regenerated fibers have the identical chemical
composition as those obtained from their parent origin, like rayon which is cellulosic in
nature. The chemical composition of synthetic fibers is predicated on the character of their raw
materials and also the chemical
reactions that occurred.
Reference:
