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DELHI PRIVATE SCHOOL DUBAI
CERTIFICATE
Certified that this practical file is the bonafide work of Master /
Miss
Class
Div
...
____________________
______________________
External Examiner
Teacher in-Charge
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Rashmi Nandkeolyar
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ajith jacob in providing a helping hand in this project
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I would like to thank my parents who supported and
also helped me in all my endeavors
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And last but not the least I
thank the Almighty for whatever I have achieved till now
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∑ Properties and uses of bakelite
∑ Theory
∑ Experiment
∑ Precautions
∑ Bibliography
INTRODUCTION
History is shaped by the materials we develop and use
...
Some 5,000 years ago, we learned how to make alloys of
copper, and the Bronze Age began
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The introduction of Bakelite the world s first synthetic plastic in
1907 marked the introduction of the Polymer Age
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"Plastic" (from the Greek "plastikos,"
meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers
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Most
polymers but not all consist of monomers that are similar to each other, joined
together in a straight chain, like a long string of pearls
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Properties and Uses of Bakelite
∑ Bakelite can be molded very quickly, an enormous advantage in mass
production processes where many identical units were produced one after
the other
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∑ Bakelite was also particularly suitable for the emerging electrical and
automobile industries because of its extraordinarily high resistance (not
only to electricity, but to heat and chemical action as well)
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∑ Along with its electrical uses, molded Bakelite found a place in almost
every area of modern life
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BANGLES
TELEPHONES(MADE WITH BAKELITE)
SWITCHES MADE OF BAKELITES
BILLIARD BALLS
Theory
Bakelite or polyoxybenzylmethylenglycolanhydride, is an early plastic
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Bakelite was a combination of phenol, formaldehyde, and wood flour
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Today, Bakelite is manufactured and
produced in sheet, rod and tube form for hundreds of industrial applications in the electronics, power
generation and aerospace industries, and under a variety of commercial brand names
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EXPERIMENT
AIM:- To prepare phenol formaldehyde resin
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∑ Under a hood, measure 25 mL of the phenol-formaldehyde reaction mixture into a
150-mL beaker
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∑ Add 10 mL of concentrated hydrochloric acid, slowly, with stirring
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(You will need
approximately 2 mL of HCl
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∑ At the point where polymerization begins, the white precipitate will not dissolve
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Wash the plastic
well before handling
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They
possess
∑ excellent adhesive properties and are usually used as bonding glue for laminated
wooden
∑ Phenol-formaldehyde resins having high degree of polymerization are hard, rigid,
scratch resistant and infusible
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They can withstand very high temperatures
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∑ They are used for making decorative laminates, wall coverings etc
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∑ They are used for impregnating fabrics wood and paper
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PRECAUTIONS
∑ Wear safety goggles at all times in the laboratory
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∑ Phenol is toxic via skin contact
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∑ Glacial acetic acid is an irritant and can cause burns on contact
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wikipedia
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youtube
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wolframalpha