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Polyphenylene Vinylene
Poly(''p''-phenylene vinylene) (PPV, or polyphenylene vinylene) is a Conducting polymers, conducting polymer of the rigid-rod polymer family. PPV is the only polymer of this type that can be processed into a highly ordered crystalline thin film. PPV and its derivatives are electrically conducting upon doping. Although insoluble in water, its precursors can be manipulated in aqueous solution. The small optical band gap and its bright yellow fluorescence makes PPV a candidate in applications such as light-emitting diodes (LED) and photovoltaic devices. Moreover, PPV can be doped to form electrically conductive materials. Its physical and electronic properties can be altered by the inclusion of functional side groups. Preparation PPVs can be synthesized by a variety of methods, the details of which determine purity and molecular weight. The most popular methods proceed via p-xylylene intermediates after a base induced elimination from α,α'-disubstituted para-xylenes. : Other me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conducting Polymers
Conductive polymers or, more precisely, intrinsically conducting polymers (ICPs) are organic polymers that conduct electricity. Such compounds may have metallic conductivity or can be semiconductors. The biggest advantage of conductive polymers is their processability, mainly by dispersion. Conductive polymers are generally not thermoplastics, ''i.e.'', they are not thermoformable. 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. The electrical properties can be fine-tuned using the methods of organic synthesis and by advanced dispersion techniques. History Polyaniline was first described in the mid-19th century by Henry Letheby, who investigated the electrochemical and chemical oxidation products of aniline in acidic media. He noted that reduced form was colourless but the oxidized forms were deep blue. The first highly-conductive orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
