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It seems preferable to have a high degree of polymer chain alignment, but with few grain boundaries and with many chains bridging between adjacent domains. Another application which relies on the optical and semiconducting properties of conjugated polymers is solar-energy conversion. In this case, each photon of solar radiation is absorbed to generate an exciton – a bound electron–hole pair. van Doren, (Eds), Highly Conducting One-Dimensional Solids, Plenum, New York and London, 1979. As several other chapters in this volume discuss in detail, polymer morphology at the nanoscale plays a crucial role in dictating the mobility. In any conductor a high degree of order is essential to achieve high mobility, since disorder leads to scattering, trapping at defects, and localization. [20] among others, highly crystalline polymers are not necessarily ideal, because the crystallites are typically much smaller than the channel length, in which case the mobility is limited by transfer across grain boundaries. Mac Diarmid returned to Pennsylvania, where he and Heeger quickly arranged to invite Shirakawa for a sabbatical visit. Scientifically, it was understood that pristine polyacetylene is a Peierls semiconductor, as evidenced by its bond-alternating structure; it was known that charge transfer to molecular donors or acceptors would result in partially filled bands and that the resulting incommensurability of the Fermi wave-vector would destabilize the Peierls phase. issue, you‟ll start to recognise familiar themes being discussed in the popular media. Standard practice was to use a concentration of the organometallic catalyst at the millimolar level. These low concentrations led to the infamous ‘insoluble, intractable, black precipitate,’ but Shirakawa had discovered that with concentrations closer to molar, he obtained a shiny ‘metallic’ film coating the wall of the reaction vessel. Yamamoto, Preparation of thermostable and electricconducting poly(2,5-thienylene), J. As issues of processability, limits on conductivity, and environmental stability became more apparent these grand schemes fell by the wayside. De Sarbo is the Smeal Distinguished Professor of Marketing at the ... There were suggestions to replace (copper) electrical wiring in everything from printed circuit boards to home, and even grid, power distribution with inexpensive, light-weight polymeric conductors.

Photographic film is a good example of the latter application and is the reason that Bayer initiated, in conjunction with Agfa, their development of the Baytron series of products based on poly(ethylenedioxythiophene) (PEDOT) doped with poly(styrene sulphonate) PSS. At that time there was great interest in nonlinear optics, as researchers were developing new materials, both organic and inorganic, for application in optical switches, modulators and the like. (In the nomenclature used in Figure 1.1, polyacetylene would be called polyvinylene. The chemical structures are illustrated in Figure 1.1. Although there was some prior work dating back to World War II (see the review by Hush [2]) and even reports of electrochemical synthesis the nineteenth century [3], the Nobel Committee recognized the seminal contribution of Heeger [4], Mac Diarmid [5] and Shirakawa [6] by awarding them the Nobel Prize for Chemistry in 2000. Campbell Scott RI AL History of Conductive Polymers Introduction D 1.1 MA IBM Almaden Research Center, San Jose CA CO PY RI GH TE It is generally recognized that the modern study of electric conduction in conjugated polymers began in 1977 with the publication by the group at the University of Pennsylvania [1] describing the doping of polyacetylene.

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