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the first highly-conductive organic compounds were the charge transfer complexes. In 1955 researchers reported that polycyclic compounds form semi-conducting salts with halogens. These compounds do have very low resistivities as | the first highly-conductive organic compounds were the charge transfer complexes. In 1955 researchers reported that polycyclic compounds form semi-conducting salts with halogens. These compounds do have very low resistivities as | ||
low as 8 ohms-cm and thats why they were and still are interesting for engineering. | low as 8 ohms-cm and thats why they were and still are interesting for engineering. | ||
Revision as of 19:05, 19 January 2015
' Conductive polymers are polymers that can conduct electricity. They can have metallic conductivity or be so called semiconductors, which have a value of conductivity between a conductor, like silver and an insulator, like normal polymers. The materials have the advantage that they have a great processability because of their organic origin. Because of that, they can offer high electrical conductivity. Those materials are not similar to mechanical properties of other polymers. Scientists are able to customize their properties by using organic synthesis or dispersion. Organic synthesis is similar to chemical synthesis where organic compounds are build by using organic reactions. Dispersion is a method where particles in the materials are dispersed to modify the chemical features.
Types:
The main class are linear-backbone "polymer blacks" Then there are the Poly(p-phenylene vinylene) or just PPV which are semiconducting polymers. The third type are the Poly(3-alkylthiophenes) which are used for solar cells and transistors. There are just a few well studied classes but a lot more that still have to be studied.
Synthesis
Conductive polymers are prepared by chemical, electrochemical and photoelectonical methods. Most conductive polymers are prepared by CVD (chemical vapour deposition). Thin layers of oxidised Material can be easily cut off to achieve the desired output.
Applications of EAP
EAP is short for ElectroActive Polymer. Such Materials can be easily manufactured into many different shapes which are very versatile. One potential application for EAPs is to integrate it into smart actuators. Artificial muscles Artificial muscles is probably the application with the best prospective. They are able to emulate the operation of biological muscles with high percision because of their strength and durability. Tactile displays Just recently electro active polymers have been used to simulate a displays. This concept is using an EAP actuator that is applied in an array form. Rows of electrodes on one side of an EAP film featuring also columns on the other side. Each individual element in the array is being opperated ba applying a voltage across the thickness of the element, causing local thickness reduction. A cnotrollable CPU display would also feature dots to create tactile patterns of highs and lows standing for information.
History
Henry Letheby was the first who described a conductive polymers, in his case it was the material Polyaniline. He noticed that materials change their colour after they have been oxidized. But this was just the beginning though,
the first highly-conductive organic compounds were the charge transfer complexes. In 1955 researchers reported that polycyclic compounds form semi-conducting salts with halogens. These compounds do have very low resistivities as low as 8 ohms-cm and thats why they were and still are interesting for engineering.
Applications of EAP
Notes and references
See also
- [[]]
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Interwiki links
- Wikipedia:http://en.wikipedia.org/wiki/Conductive_polymer
- Wikipedia:http://en.wikipedia.org/wiki/Dispersion_(chemistry)
- Wikipedia:http://en.wikipedia.org/wiki/Organic_synthesis
External links
[[Category:]] [[Category:]]