gement
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equired
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INDEX
ACKNOWLEDGEMENT
I would like to thank the CBSE, for providing me the opportunity
to carry out this investigatory project. I would also like to express
my special thanks of gratitude to my Physics teacher, Mr.
Bhagwatsingh Rawat, our lab assistant and as well as our
principal Mrs. Anjali Kwatra, for guiding me and imparting a
sound base of knowledge pertaining to this topic which ensured
the successful completion of this project.
I completed this project not only as physics project, but also to
increase my knowledge.
AIM OF THE PROJECT
The objective of the project is to illustrate the
preparation of rayon thread by the
cuprammonium process. Instead of wood pulp
as cellulose source, it is attempted to use raw
cellulose products such as unprinted paper.
INTRODUCTION
Cellulose is a natural polymer found in the plant kingdom. It consists
of long chains of beta glucose. Cellulose has wide ranged
applications in the modern world. Cellulose derivative polymers like
rayon (cellulose acetate) are called semi synthetic polymers.
Wood is the major source of cellulose for industrial purposes. Since
it is only about 40-50% cellulose, cellulose is derived from it by the
process of pulping.
Rayon is used widely for the production of various products of
everyday use.
It is used in the textile industry for making textiles because of its
comfort properties similar to those of natural fibers. It is also used
for making tyre cords, carpets and surgical dressings.
REQUIREMENTS
Apparatus: Conical flask, funnel, glass rod, beaker, water bath, and
filter paper.
Chemicals: Copper sulfate crystals, Sodium hydroxide solution, dilute
sulfuric acid, liquor ammonia.
THEORY
Rayon can be obtained by the Cuprammonium Process.
It can be prepared by dissolving pieces of filter paper in a deep blue
solution containing tetra-ammine cupric hydroxide. The latter is obtained
from a solution of copper sulfate. The paper bits supply the cellulose
necessary for reaction.
The reactions involved are:
CUSO4+ 2NH4OH
Cu(OH)2+ (NH4)2S04
Pale Blue ppt
Cu(OH) 2 + 4NH4OH — [Cu(NH3) 4](0H) 2 + 4H2O
Bits of paper are added to this solution and it is left undisturbed for about 15 days. A
Viscous solution called viscose is obtained.
PROCEDURE
A.
Preparation of Schweitzer’s Solution:
a) Weigh 20g of CuSO4.5H20.
b) Transfer this to a beaker having 100ml distilled water and
add 15ml of dilute H2SO4 to prevent hydrolysis of CuSO4.
c) Stir it with a glass rod till a clear solution is obtained. Add
11ml of liquor ammonia drop by drop with slow stirring. The
precipitate of cupric hydroxide is separated out. or wash it
down the funnel.
d) Filter the solution containing cupric hydroxide through a funnel
with filter paper.
e) Wash the precipitate of cupric hydroxide with water until the filtrate
fails to give a positive test for sulfate ions with barium chloride
solution.
f)Transfer the precipitate to a beaker that contains 50ml of liquor
ammonia or wash it down the funnel. The precipitate when dissolved
in liquor ammonia gives a deep blue solution of tetra-ammine cupric
hydroxide. This is known as SCHWEITZER’S SOLUTION.
B. Preparation of Cellulose material
a)After weighing 2g of filter paper divide it into very fine pieces and
then transfer these pieces to the tetra-ammine cupric hydroxide
solution in the beaker.
b) Seal the flask and keep for 10 to 15 days, during this period the
filter paper is dissolved completely.
PHOTOGRAPHS
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BIBLIOGRAPHY
1.
2.
https:/www.wikipedia.co.in
https:/www.brittanica.co.in
3. NCERT chemistry class 12 book.