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DEFINITION OF PLASTIC
HISTORY
TYPES
PRODUCTION
USES
ADVANTAGES
DISADVANTAGES
PROPERTIES

DEFINITION OF PLASTIC
 Plastics comes from
the Greek word
plastikos, which means
to form or to mold.
All synthetic polymers are considered
plastics .
Plastic is a common
name for Polymers:
materials made of long
strings of carbon and
other elements.

HISTORY
The development of plastic materials started with the use of natural
materials with plastic properties (e.g., chewing gum) then evolved
with the development of chemically modified natural materials (e.g.,
rubber, nitrocellulose, collagen, galalite) and finally the wide range of
completely synthetic material that we would recognise as modern
plastics started to be developed around 100 years ago. Perhaps the
earliest example was invented by Alexander Parkes in 1855. We know
it today as celluloid, but he named it Parkesine. Polyvinyl chloride
(PVC) was first polymerised between 1838-1872 and a key
breakthrough came in 1907 when Leo Baekeland created Bakelite, the
first real synthetic, mass-produced plastic.

THERMOPLASTICS
THERMOSETS

THERMOPLASTICS:
 Soften with heat and
harden with cooling.
 Thermoplastics can be
reshaped anytime by
reheating the part – thus,
making it easy to recycle.
 The concept of
thermoplastics is much
like wax from a candle.
When heat is applied, it
melts and turn into molten
liquid. While in liquid
state it can easily be
shaped by a mold.

Are hardened by heat.
Unlike thermoplastics, thermosets
cannot be recycled.
The concept of thermosetting is
similar to baking cakes or bread.
Firstly, the material is shaped like a
dough and placed into a mold. Then
heat is applied to the mold and the
material expands (just like baking a
bread in an oven) to take the shape of
the mold. After curing, the final
product is removed from the mold.

FROM RAW MATERIAL TO PLASTIC PRODUCT:

It lasts forever .
It is very cheap to make.
It does not decompose but it can instead
be recycled.
It can be converted back into oil.
Easy to work with.
Heat insulating.
No electrical conductivity.
Resistant.

when it is melted the compound
gas that is given off is very harmful
for our health and environment; it
weakens the ozone layer.
The world is gradually running out
of oil.

Properties:
Plastics are used because they
are:
Easy to recycle
Hard and slippery
Rubbery
Tough and slippery
Flexible
Good insulators of heat or
electricity
Light weight
Non-rusting
Easy to shape and colour
Cheap

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