1. Poly Vinyl Chloride.
Accidental miracle…….

2. Introduction
 PVC is the third most used plastic after polyethylene
and poly propylene. Due to its duarability strength and
cost effectiveness it has wide applications.
 On adding plasticizers it is being used as pthalates
which is used in clothing industry, inflatable material
and rubber replacement industries.
 Pure PVC is a white brittle solid, it is insoluble in
alcohol but slightly soluble in Tetra hydro furan.

4. Discovery
 It was discovered by two chemists working
independently in the nineteenth century. Surprisingly
it was accidental.
 The polymer appeared as a white solid inside flasks of
vinyl chloride that had been left exposed to sunlight.
 It was more flexible and more easily processed
material and hence is widespread in its applications.

5. Production
 PVC is produced by polymerisation of monomer vinyl
chloride.
 The production involves suspension and emulsion
polymerization where suspension has a major share.
 The structure of polymer is linear.

6.  Polymerisation of PVC takes place by addition
polymerisation mainly by free radical mechanism.
 The monomers are mostly arranged head to tail, that is
chlorides on alternating carbon centres.
 PVC has mainly atactic stereo chemistry, which means
that the relative spatial arrangements of the chloride
centres are random.

7. Suspension polymerisation
 Vinyl chloride monomer and water along with
polymerisation initiator and other additives are taken
into a reactor.
 The reactor is pressurized and the contents are
continually mixed to maintain the suspension and to
ensure the uniform size of formed PVC.
 The reaction is exothermic and thus requires cooling
 As the volume is continually reduced water is added to
maintain the suspension.

8. Additives
 PTHALATE PLASTICIZERS- Plasticizers are
compounds that improve the performance
characteristic quotient of PVC. They must have less
volatility and less toxicity. The following is Bis(2-ethyl
hexyl)pthalate.

9.  HEAT STABILIZERS - These are one of the most
important additives. These agents minimise loss of
HCl which is a degradation process that starts at 70
degree celsius.
Once dehydrochlorination starts the process is
autocatalytic and hence it must be minimised.
Derivatives of heavy metals and Calcium stearate are
traditional heat stabilizers.

10. PHYSICAL PROPERTIES
 Glass Temperature - 82 degree celsius
 Melting Temperature – 100 to 260 degree celsius
 Effective Heat of Combustion – 17.95 MJ/Kg
 Specific Heat – 0.9 KJ/(kg.K)
 Density – 1.1 to 1.45 g/c.c

11. Properties
 Mechanical- PVC has high hardness. These properties
increases with increasing molecular weights and
decreases with increasing temperatures.
 Thermal- As the heat stability of PVC is very poor we
are adding the heat stabilizers. It starts to decompose
at 140 degrees Celsius and melts at 160 degree Celsius.
 Electrical- PVC is a polymer with good insulation
properties and generally suitable for medium or low
voltage and low frequency insulations.

12. Chlorinated PVC
 PVC can be usefully modified by chlorination, which
increases its chlorine content .The new material has
higher heat resistance so it is primarily used for hot
water pipes and fittings.
CPVC is produced by chlorination of aqueous
solution of suspension PVC particles followed by
exposure to UV light which initiates the free radical
chlorination.

13. Applications
PVC is relatively low cost, biological, chemical resistance
and workability of it resulted in it being used in many
applications.
 PIPES- It is used for sewage pipes and other pipe
applications where cost or vulnerability to corrosion
limit the use of metal.
 Electrical cables- PVC is an insulator and hence used
for insulation of electric cables. For this purpose it
must be plasticized

15. Other applications
 It is used in
Construction
Clothing
Furniture
Sports
Health care
Flooring
The image is of a black
PVC pants.

16. Disadvantages
 Recycling difficulty
 It is not recommended for use above 70 degrees




Celsius.
Sensitive to UV and oxidative degradation.
Limited thermal capability.
Thermal decomposition evolves HCl.
Higher density than many plastics.

17. REFERENCES
 www.australianresearch.com
 www.google.com
 www.sciencedirectory.com
 Wikipedia

18. THANK YOU
A presentation by
P S V Sai Teja.
D Pramod Reddy.
K Vishnu Teja Reddy.
Nazeem.
B Laxmidhar .