i bam student of textile science

1. Hamza sameen
Assignment of
Textile
Method of identification of fiber:-
 Through burn test.
 Through Microscopic Analysis.
 Behaviors in Solution.
Identification of cotton fiber by burn:-
Burns, but does not melt. It has the odor of burning
paper leaves, or wood. The residue is a fine, feathery,
gray ash.

2. Microscopic analysis:-
 The cotton fiber is a single elongated cell.
 Under a microscope, it looks like flat, spirally
twisted ribbon like tube with rough granular
surface.
 However, mercerized cotton doesn't have
natural twist.
 The finishing process makes them swollen,
straight, smooth and round with a shining
surface.
 The thin cell wall of the fiber has from 200 to 400
convolutions per inch.


3. Chemical test:-
 As strong alkali destroy animal substances, a
5%of soda lye solution in water can be used to
eliminate wool and silk fibers from a sample
that contains a mixture of fiber.
 The vegetable fibers will not be affected by this
solution.
WOOL FIBER:-

4. Burn testing:-
 It is also a protein fiber but is harder to ignite
than silk as the individual "hair" fibers are
shorter than silk and the weave of the fabrics is
generally looser than with silk.
 The flame is steady
but more difficult to keep
burning. The smell of
burning wool is like
burning hair.
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5.  Wool Fiber has irregular, roughly cylindrical, multi cellular
structure with tapered ends.
 Under a microscope, three basic layers are shown- epidermis
(outer layer), cortex (middle layer) and medulla (inner
layer).
 Medulla is seen only in coarse and medium wool fibers and
that too under a highly powerful microscope.
Chemical Test:-
 The use of concentrated cold hydrochloric acid will dissolve
the silk and the wool fiber swells.

6. LINEN:-
Burn Test:-
 Linen takes longer to ignite.
 The fabric closest to the ash is very brittle.
 Linen is easily extinguished by blowing on it as you
would a candle.
Microscopic analysis:
 Under the microscope, the hair like flax fiber shows
several sided cylindrical filaments with fine pointed
ends.
 The fiber somewhat resembles a straight, smooth.

7. Chemical Test:-
 Cotton and linen are immersed in a 1% solution of
fuchsine in alcohol to give red rose color.
 Later, they are washed and immersed into ammonia,
linen retains the red coloration but cotton does not.
SILK:-
Burning Test:-
 It is a protein fiber and usually burns readily, not
necessarily with a steady flame, and smells like
burning hair.
 The ash is easily crumbled. Silk samples are not as
easily extinguished as cotton or linen.

8. Microscopic analysis:
 It appears somewhat elliptical and triangular in cross
section.
 When we see under the microscope it is composed of
fibroin, consisting of two filaments, called brim which
is held together by service.

9. Chemical Test:-
 The use of concentrated cold hydrochloric acid will
dissolve the silk and the wool fiber swells.
Man Made Fibers:-
Acetate:
Burning test:
 Acetate burns readily with a flickering flame that
cannot be easily extinguished.
 The burning cellulose drips and leaves a hard ash.
 The smell is similar to burning wood chips.
Microscopic analysis:
 The cross sectional view has a bulbous or multi global
appearance with indentations.

10.  These
indentations appear as occasional markings.
Rayon:-
Burning test:
 It is a regenerated cellulose fiber which is almost pure
cellulose.
 Rayon burns rapidly and leaves only a slight ash.
 The burning smell is close to burning leaves .

11. Microscopic analysis:
 Rayon fibers have a glasslike luster under the
microscope and appear to have a uniform diameter
when viewed longitudinally

12. POLYESTERS:
Burning test:
 Polyester melts and burns at the same time, the
melting, burning ash can bond quickly to any surface
it drips on including skin.
 The smoke from polyester is black with a sweetish
smell.
 The
extinguished ash is
hard.

13. Microscopic analysis:-
 Generally, polyester fibers are smooth and straight
and the cross-section is round.
 These general characteristics may be altered to
achieve certain characteristics.
CHEMICAL TEST:-
 Polyester is soluble in hot Meta cresol; however, unlike
acetate it is not soluble in acetone, and unlike nylon.
 it is not soluble in concentrated formic acid.