Page 36 - Genius Kidz Prudence Learning Sc-8

of
mation
for
polymer
a

the
is
olymerization
of
process
P
b
smaller
tog
ether
of
units

y
called
! Polymerization is the process of formation of a polymer by linking together of smaller units called
linking
! ! Polymerization is the process of formation of a polymer by linking together of smaller units called
“monomer”.
“monomer”.
“monomer”.
! ! Synthetic fibres and plastics are the examples of polymers.
and
fibres
! Synthetic fibres and plastics are the examples of polymers. .
Synthetic
plastics
the

of
examples
polymers
are
acrilan.
and
fibres
include
y
ra
on,
polyester
nylon,
! ! Synthetic fibres include rayon, nylon, polyester and acrilan.
Synthetic
! Synthetic fibres include rayon, nylon, polyester and acrilan.
ther
! Plastic can be thermosetting or thermoplastic. .
mosetting
Plastic
! ! Plastic can be thermosetting or thermoplastic.
or
can
be
moplastic
ther
compared
ther
moplastics
to
! ! Thermosetting is superior as compared to thermoplastics.
.
mosetting
T
is
her
as
! Thermosetting is superior as compared to thermoplastics.
superior
EXERCISE
EXERCISE
1. Multiple choice questions.
(a) ______________ was the first semi-synthetic polymer.
(i) Bakelite (ii) Rayon (iii) Nylon (iv) PET
(b) ______________ fibre is similar in properties to wool.
(i) Rayon (ii) Orion (iii) PET (iv) Nylon
(c) A thermoplastic is that plastic which has the following properties :
(i) High molecular weight and remoulding capacity.
(ii) Low molecular weight and brittle.
(iii) Low molecular weight and glassy.
(iv) None of the above.
2. Fill in the blanks.
(a) ________ is the first semi-synthetic fibre.
(b) Rayon is an ____________.
(c) Toothbrush bristles are made up of __________.
(d) Terrycot is ________.
3. Match the columns.
Column A Column B
(a) Polyester (i) Fruit juice bottle
(b) PET (ii) Light weight shawls
(c) Acrilan (iii) Teflon
(d) Tetrafluoroethene (iv) Thermosetting
(e) Bakelite (v) PET
4. Mark the statements as True /False .
(a) Nylon is an example of natural polymer.
(b) Latex is an artificial polymer.
(c) Nylon can retain dyes.
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