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|Section2= }} Polyfluorenes are a class of polymeric materials. They are of interest because similar to other conjugated polymers, they are currently being investigated for use in light-emitting diodes, field-effect transistors, and plastic solar cells. They are not a naturally occurring material, but are designed and synthesized for their applications. Modern chemistry has enabled adaptable synthesis and control over polyfluorenes that has facilitated use in many organic electronic applications. Academic and industrial research are interested in these polymers because of their optical and electrical properties. They have high photoluminescence quantum yields. They are a prototypical conjugated polymer but they are the only class of conjugated polymers which can be tuned to emit light throughout the entire visible region. Polyfluorenes are primarily interesting because of the optoelectronic properties imbued by their chromophoric constituents and their extended conjugation. The design of polyfluorene derivatives relies on the character and properties of their monomers. Thus, the discovery and development of these polymeric repeat units has had a profound influence on the development of polyfluorenes. The physical properties of polyfluorenes differ depending on their substitution pattern. ==History== Despite the similar sounding names, polyfluorene is unrelated to the element fluorine. Fluorene, a principal repeat unit in polyfluorene derivatives, was isolated from coal tar and discovered by Marcellin Berthelot prior to 1883. Its name originates from its interesting fluorescence, fluorene became the subject of chemical-structure related color variation (visible rather than luminescent), among other things, throughout the early to mid-20th century. Since it was an interesting chromophore researchers wanted to understand which parts of the molecule were chemically reactive, and how substituting these sites influenced the color. For instance, by adding various electron donating or electron accepting moieties to fluorene, and by reacting with bases, researchers were able to change the color of the molecule.〔 The physical properties of the fluorene molecule were recognizably desirable for polymers; as early as the 1970s researchers began incorporating this moiety into polymers. For instance, because of fluorene’s rigid, planar shape a polymer containing fluorene was shown to exhibit enhanced thermo-mechanical stability. However, more promising was integrating the optoelectronic properties of fluorene into a polymer. Reports of the oxidative polymerization of fluorene (into a fully conjugated form) exist from at least 1972. However, it was not until after the highly publicized high conductivity of doped polyacetylene, presented in 1977 by Heeger, MacDiarmid and Shirakawa, that substantial interest in the electronic properties of conjugated polymers took off. As interest in conducting plastics grew, fluorene again found application. The aromatic nature of fluorene makes it an excellent candidate component of a conducting polymer because it can stabilize and conduct a charge; in the early 1980s fluorene was electropolymerized into conjugated polymer films with conductivities of 10−4 S cm−1. The optical properties (such as variable luminescence and visible light spectrum absorption) that accompany the extended conjugation in polymers of fluorene have become increasingly attractive for device applications. Throughout the 1990s and into the 2000s, many devices such as organic light-emitting diodes (OLEDs), organic solar cells., organic thin film transistors, and biosensors have all taken advantage of the luminescent, electronic and absorptive properties of polyfluorenes. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Polyfluorene」の詳細全文を読む スポンサード リンク
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