Organic electronics
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Organic electronics, or plastic electronics, is a branch of electronics that deals with conductive polymers, or plastics. It is called 'organic' electronics because the molecules in the polymer are carbon-based, like the molecules of living things. This is as opposed to traditional electronics which relies on inorganic conductors such as copper or silicon.
Conductive polymers are lighter, more flexible, and less expensive than inorganic conductors. This makes them a desirable alternative in many applications. It also creates the possibility of new applications that would be impossible using copper or silicon.
New applications include smart windows and electronic paper. Conductive polymers are expected to play an important role in the emerging science of molecular computing.
Conductive polymers have a higher resistance and therefore conduct electricity slowly and inefficiently, as compared to inorganic conductors. Researchers currently are exploring ways of "doping" organic semiconductors, like melanin, with relatively small amounts of conductive metals to boost conductivity. However, for many applications, inorganic conductors will remain the only viable option.
McGinness, Corry, and Proctor reported a high conductivity state in a polyacetylene and the first organic electronic device. This was a voltage-controlled switch (Science, vol 183, 853-855 (1974)). These researchers further patented batteries, etc. using organic semiconductive materials. Their orginal "gadget" is now in the Smithsonian's collection of early electronic devices.
However, though in a major journal, this early work was lost and went uncredited. Consequently, the men principally credited for the discovery and development of conductive organic polymers were Alan J. Heeger, Alan G. MacDiarmid, and Hideki Shirakawa, who were jointly awarded the Nobel Prize in Chemistry in 2000.
Examples of electrically conductive polymers include polyacetylene: PA (more specificially iodine-doped trans-polyacetylene); polyaniline: PANI, when doped with a protonic acid; and poly(dioctyl-bithiophene): PDOT. Every electrically conductive polymer is conductive due to resonance stabilization and delocalization of pi electrons along entire polymer backbones.