Hope this helps guys ^_^

1. Synthetic
Polymers

2. By:
Soo Ying Yu
Sharanya
Mohanadas
Christina Ong
Ng Yi Von
Tan Kah Peng

4. Polymers are large molecules made up of
many smaller and identical repeating units
joined together by covalent bonds . These
molecules are called monomers .
Polymerization is the chemical process by
which the monomers are joined together to
form a big molecule known as a polymer .
A polymer is a macromolecules (a very big
molecules) . Hence , the relative molecular
mass of a polymer is large .
The properties of a polymer are different from
its monomers .

5. POLYMERS CAN BE DIVIDED INTO 2 TYPES:
a) Naturally occurring polymers
Polymers that exists in living things
in nature (plants and animals)
b) Synthetic polymer
Polymers that are man-made by
chemical processes in the
laboratories.

6. Natural polymers Synthetic polymers
 Exist in living things in nature
(plants or animals)
 Examples:-
(1) Protein
- amino acids protein
(monomer) (polymer)
(2) Carbohydrates
- glucose carbohydrate
(monomer) (polymer)
(3) Natural rubber
- isoprene natural rubber
(monomer) (polymer)
 Polymers that are man-
made by chemical
processes in the
laboratories
 Many of the raw materials
for synthetic polymers are
obtained from petroleum,
after the refining and
cracking processes
 Example:-
(1)Plastics
(2) Fibres
(3) Elastomer
 2 types of polymerisation:-
(1) Addition polymerisation
(2) Condensation
polymerisation

7. Synthetic
Polymer

8. Synthetic Polymer Advantages Disadvantages
Thermoplastics • Light
• Low processing
costs
• High strength
• Melt
• Deformed when exposed
to high levels of stress
• Chemical Leaching
Thermoset • retain their strength
and shape even
when heated
• Cannot be recycled
• Cannot be remolded or
reshaped
Elastomer • Recyclable Material
• Resistance
• Soft
• Relatively high cost
• If heated to a relatively
high temperature, they
tend to lose their
‘rubbery’ property
Synthetic fiber • cheaper than
natural fiber
• Easy to wash and
dry up quickly
• Synthetic fibers burn
more easily
• Damage by hot washing

9. Synthetic Rubber
made by mixing two by-products of
petroleum refining, butadiene and
styrene.
mixed with soapsuds to make liquid
latex
then dried into bits and pressed into
bales
about 70 percent of all
rubber is synthetic

11. Types of synthetic rubber

12. Plastics
Polyethene
Polyamide

13. Nylon 6-6
 high mechanical strength, great rigidity,
and good stability under heat is required
 carpet fibres, tyres, zip ties, ropes,
conveyor belts, hoses

15. ELASTOMER
 A polymer that can regain its original shape after
being stretched or pressed.
 For example : Both natural rubber and synthetic
rubber.
 Two types of polymerization processes:
 Addition polymerization
 Condensation polymerization
 Addition polymerization - Plastics such as
polythene and PVC
 Condensation polymerization - Synthetic fibers
such as nylon and Terylene.

16. PROPERTIES OF SYNTHETIC
POLYMERS
The physic properties of a polymer, such as its
strength and flexibility depend on :
Chain length – the longer the chains the
stronger the polymer
Side groups – polar side groups give stronger
attraction between polymer chains, making the
polymer stronger.
Cross-linking – if polymer chains are linked
together extensively by covalent bonds, the
polymer is harder and more difficult to melt.

17. POLLUTION PROBLEM CAUSED BY
SYNTHETIC POLYMERS
1. Non-biodegradable - cannot be decomposed by
bacteria or other microorganisms.
 Disposal problems - not decay like other
organic garbage.
2. Discarded plastic items may cause blockage of
drainage systems and rivers.
 Flash floods
3. Plastic bottles and containers that are not buried
in the ground will become breeding grounds for
mosquitoes.
 Dengue

18. 4. Small plastic items that are thrown into the rivers,
lakes and seas are sometimes swallowed by
aquatic animals.
 Animals die from choking
5. The open burning of polymers may release
harmful and poisonous gases that will cause air
pollution.
 Burning of PVC will release hydrogen
chloride gas which contributes to the acid
rain problem.

19. METHODS TO OVERCOME
ENVIRONMENTAL PROBLEMS OF
POLYMERS
 Reused - Collected and reused or
reprocessed to make new items.
 Reduce - Reduce the use of non-
biodegradable polymers.
 Recycle

20. DEVELOP BIODEGRADABLE
POLYMERS
 The polymers can be decomposed by
bacteria, other microorganisms or simply by
sunlight (photodegradable).
 One type of biodegradable polymer was
developed by incorporating starch molecules
into the plastic materials so that they can be
decomposed by bacteria.

21. Make the world a better place.