Rubber is a polymer that is elastic and can return to its original shape after being stretched or deformed. It is made of polymer chains that coil when at rest but can be stretched apart and will snap back into position when tension is released. The main types of rubber are natural rubber from rubber trees and synthetic rubber produced from petroleum. Natural rubber comes from the polymerization of the monomer isoprene and latex from trees. Synthetic rubber has similar properties but is made artificially and is cheaper than natural rubber. Common uses of both natural and synthetic rubbers include tires, hoses, gloves and footwear.

2. Introduction
 Rubber is an example of an elastomer type polymer,
where the polymer has the ability to return to its original
shape after being stretched or deformed.
 The rubber polymer is coiled when in the resting state.
 The elastic properties arise from the its ability to stretch
the chains apart, but when the tension is released the
chains snap back to the original position.

3.  The majority of rubber polymer molecules contain at least
some units derived from conjugated diene monomers.
 Such conjugated diene monomers have a constructive
backbone of at least four carbon atoms with a double-
single-double bond reactive core (C=C-C=C ).

4. Types of Rubber
Types
of
Rubber
Natural
Rubber
Synthetic
Rubber

5. NATURAL RUBBER
 Natural rubber is an addition polymer
that is obtained as a milky white fluid
known as latex from a tropical rubber
tree.
 Natural rubber is from the monomer
isoprene (2-methyl-1,3-butadiene),
which is a conjugated diene
hydrocarbon .
 It comes from latex.
 Names of the Trees: Hevea Brasiliensis
and Castilloa elástica.
 Elastic, water repellent and electric
resistent.

6. NATURAL RUBBER
HISTORY
 Discovered by the mayans and aztecs.
 Banned in the 15th century.
 La Condamine rediscovered it in 1735.
 It was a success in Europe.
 In 1791 it was first commercialized.

7. NATURAL RUBBER
RECYCLING
 Different processes to recycle it.
 Very flammable.
 It creates pollution.
 Cause of diseases.
 E.g: Rubber floors for parks.

8. NATURAL RUBBER
USES
 Tires.
 Wheel rims.
 Hoses.
 Conveyor belt.

9. SYNTHETIC RUBBER
DESCRIPTION
• Artificial elastomer:Important conjugated dienes used in
synthetic rubbers include isoprene (2-methyl-1,3-
butadiene), 1,3-butadiene.
• Polymerized 1,3-butadiene is mostly referred to simply as
polybutadiene. Polymerized chloroprene was developed
by DuPont and given the trade name Neoprene.

10.  Obtained mainly from petroleum.
• Elastic material.
• Good qualities and cheap.
• It is recyclable.

11. SYNTHETIC RUBBER
HISTORY
• Created in 1909 by Fritz Hofmann.
• Similar structure to natural rubber.
• People were very pleased.
• Cheaper than natural rubber.
• 2/3 of today’s rubber is synthetic.

12. SYNTHETIC RUBBER
PROPERTIES
• Solid, flexible, durable.
• It hardens when it’s cooled.
• It can be molded when heated.
• Resistant to heat, light and
chemicals.
• Heat and electrical insulator.

13. SYNTHETIC RUBBER
USES
• Car tires.
• Flexible rubber toys.
• Paint.
• Shoe soles.
• Rubber gloves.
• Tubes and hoses.

14. Neoprene:A Synthetic rubber
Properties
 Synthetic rubber.
 It’s produced by polymerization of chloroprene.
 It has good chemical stability.
 Flexible over a wide temperature range.
 It is colourless.
 Resistant to sun, climate and ozone deterioration.

15. Neoprene
HISTORY
 It was invented by DuPont scientist (1930).
 First name: DuPrene.
 It smelled bad and was expensive.
 Problems were solved and was a success.
 It name was changed to neoprene.

16. NEOPRENE
RECLYCLING
 Waste burying techniques.
 Incineration.
 Some brands do recycling processes.
 Using old neoprene to create shoes, t-shirts…

17. NEOPRENE
USES
 Laptop sleeves
 Wetsuits
 Small boats
 Boots
2

18. References
1.A text book of engineering Chemistry by shashi Chawla
2.https://www.Google.com
3. Engineering Chemistry by Jain and Jain