1. Conducting polymers

2. Conductive polymers are organic polymers that conduct electricity.
These polymers are not thermoplastics but like insulating polymers,
they are organic materials.
They can offer high electrical conductivity but do not show similar
mechanical properties to other commercially available polymers.
Conductive polymers are prepared by oxidative coupling of
monocyclic precursors.
In 1977, Shirakawa, MacDiarmid, and Heeger were able to increase
the conductivity of trans polyacetylene samples, after doping, to a
conductivity of about 1000 S/m or 1 S/cm. They got Nobel Prize in
2000.
INTRODUCTION

4. Polyacetylene
Properties/Characteristics:
Polyacetylene has been produced by several methods, many utilizing the
Zeigler–Natta polymerization systems.
Both cis and trans isomers exist. The cis polyacetylene is copper-
colored with films having a conductivity of about 10-8 S/m. By
comparison, the trans-polyacetylene is silver-colored with films
having a much greater conductivity on the order of 10-3 S/m.
The cis isomer is converted into the thermodynamically
more stable trans isomer by heating (150 °C).
Conductivity is greatly increased when the trans-
polyacetylene is doped (to about 10^2 – 10^4 S/cm).

5. CONJUGATED CONDUCTING POLYMERS
The carriers of electron conducting polymers are free electrons and their
common characteristic is a long π-conjugated system in the molecular
skeleton, which results in delocalised electrons.
These molecules are called conjugated conducting polymers.
To efficiently increase the movement of electrons in the π-system, the energy
level difference caused by energy band splitting should be reduced to easily
overcome the energy difference between the full and empty bands.
They are widely used in organic solar cells (OSCs), organic field effect
transistors (OFETs), sensors, and colour-changing coatings.

10. Extrinsic conducting polymers
Those conducting polymers which owe their conductivity due
to the presence of externally added ingredients in them are
called extrinsically conducting polymers.
Extrinsically conducting polymers (ECP’s) are of two types.
These are: (1) conducting elements filled polymers(CEFP),
and (2) blended conducting polymers(BCP)

11. 1.CONDUCTING ELEMENTS FILLED POLYMERS
In this type, a conducting element is added to the polymer.
The conducting material will have more surface area and more porosity.
Therefore, the polymer acts as a binder to hold the conducting elements
together in solid entity.
Thus, conductivity of these polymers is due to the addition of external
ingredients.
Upon addition of conducting element, the polymer will have a property of
that conducting element and it will start conducting electricity.

12. EXAMPLE:

13. Properties/Characteristics:
Poly(3-hexylthiophene) (P3HT) is a derivative of
polythiophene. The two major steps for the preparation is
Grignard metathesis polymerization, and quenching reaction.
P3HT is popular because of its wide availability, low cost,
well-known morphology, and easy processability.
P3HT is a semicrystalline polymer and its backbone is made
up of isolated rings and linear side chains. This structural
arrangement enables the freedom to sample conformational
space.
It is used in personal mobile phone charger, solar panel,
organic transistors.

15. 2.Blended conducting polymers
These types of polymers are obtained by blending a conventional
polymer with a conducting polymer either physically or chemically.
This blend of polymers conduct electricity.
Such polymers can be easily processed and possess better physical ,
chemical and mechanical properties.
Examples: poly(styrene) (PS)–poly(phenylene oxide) (PPO) and
poly(styrene-acrylonitrile) (SAN)–poly (methyl methacrylate)
(PMMA).

17. THANK YOU
BY- M.SHRI HARSHA(478)
S.SHYLENDRAN(519)
RAHUL V.K.(529)