Page 29 - Science Class 08

and moist condi on. Prolonged exposure Thread Weight Required to Break the Thread
to sunlight causes loss of strength because
of degrada on of cellulose chains.
NYLON
Nylon was the first synthe c fibre to be made
en rely of chemicals. It derives its name from
the ci es of New York and London, where it
was first marketed.
Nylon fibre is very strong and elas c, in fact,
nylon thread is stronger than steel wire. It is
light and wrinkle-resistant. It is also wear-
resistant, that is why nylon garments last for a
long me. It is easy to wash and absorbs very
li le water, therefore garments made from
nylon dry quickly. It is lustrous in appearance.
Nylon
Tensile Strength of Fibres
Take threads of co on, wool, silk and nylon
of about the same length and thickness.
Hang one of them from a stand. A ach a pan
at the other end of the thread. Add weights,
one-by-one, to the pan un l the thread
breaks. Note the total weight required to
break the thread. This gives a measure of the
tensile strength of the thread. Repeat with
the other threads. Tabulate your results and
compare the strengths of the threads.
Science-8
Co on
Wool
Silk
Nylon
We all use umbrellas, stockings, socks, tooth-
brushes in our day to day lives. Most of us have
also come across the term ‘nylon’ at some
point or other. But, have you ever stopped to
consider what is nylon? How can one material
be both plas c-like as in bristles and pliable as
in a pair of socks? Nylon is an umbrella term for
synthe c materials that can be processed into
different shapes and textures to be put to
various uses.
What is Nylon Made of?
Nylon is a plas c with super-long, heavy
molecules built up of short, con nually repea ng
sec ons of atoms. The polymers can be mixed
with various substances to achieve different
varia ons in proper es, which explain why this
material has such a varied use.
Advantages of Fabrics Made of Nylon
v Fabrics made of nylon dry quickly.
v They are long las ng.
v They are light and wrinkle free.
Disadvantages of Fabrics Made of Nylon
v They catch fire easily.
v They are not comfortable in the summer
season.
Other Uses of Nylon
v In making ropes, parachutes, fishing nets,
etc. because nylon fibres are very strong
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