Conducting polymers optical properties

The relationship between material properties and structure was often disputed as the conductivity and optical properties for the same material are often found to be very different from one group of researchers to another. Sophisticated models have been widely used to account for the electron-phonon coupling for various polymers including the twist motion along the backbone, while many attempts were made to explain the variation of the current as a function of the structure or the temperature [1-4]. 

Polymer clay nanocomposites are already used in many applications to enhance existing properties of a particular material, and development should be focused on the true multifunctional materials. Certainly, clay nanocomposites will continue to be used for enhanced mechanical, flammability, and gas barrier properties, but fundamental limits in clay chemistry prevent them from being used easily in applications requiring electrical/ thermal conductivity or optical properties. Similarly, combinations of... 

L.R. Dalton, J. Thompson and H.S. Nalwa, The role of extensively delocalized n-electrons in electrical conductivity, nonlinear optical properties and physical properties of polymers. Polymer, 28 543 (1987). 

Based on these three criteria, more than two hundred polymers were chosen for inclusion in this work. The properties presented for each polymer include some of great current interest, such as surface and interfacial properties, pyrolyzability, electrical conductivity, nonlinear optical properties, and electroluminescence. Not aU the properties are available for all the polymers included, and some properties may not even be relevant for certain polymer classes. Some polymers exhibit properties shown by few others—such as electrolununescence—and those have been presented as "Properties of Special Interest."... 

Every attempt has been made to include modem topics not covered in a convenient handbook format elsewhere, such as scaling and fractal dimensions, computational parameters, rotational isomeric state models, liquid-crystalline polymers, medical applications, biodegradability, surface and interfacial properties, microUthography, supercritical fluids, pyrolyzabil-ity, electrical conductivity, nonlinear optical properties, and electroluminescence. 

Polymers — prepared via the polymerization of 2-bromomagnesio-5-bromo-3-alkylthiophenes — exhibit enhanced conductivity and optical properties when compared with regiorandom materials [58,59]. Another approach to regioregular alkylpoly(thio-phene)s is the usage of zinc instead of magnesium in nickel- or palladium eatalyzed polymerizations [60,61]. Due to the improvements, these synthetic methods are by far the most valuable synthetie routes to these materials. In contrast, the regioselective synthesis of substituted poly(pyrrole)s was not reported to date. 

Smart materials. 2. Polymers—Optical properties. 3. Conducting polymers. 4. Photoreffactive materials. 5. Photobiochemistry. 

Different methods were widely used for the study of fundamental structure and dynamics properties of conductive polymers optical and X-ray photoelectron spectroscopy, scanning electron miCToscopy (SEM), chromatography, dc and alternating current (ac) conductometry, microwave dielectrometry, Faraday balance and alternating force magnetometry, and thermoelectric power. As the electronic properties of... 

M.-S. Jang and H.-K. Shim, Synthesis, electrical conductivity and optical properties of multifunctional poly[2-(2-ethyl-hexyloxy)-1,4-phenylenevinyl-ene], Polym. Bull. 35 49 (1995). 

The polysdanes are normally electrical insulators, but on doping with AsF or SbF they exhibit electrical conductivity up to the levels of good semiconductors (qv) (98,124). Conductivities up to 0.5 (H-cm) have been measured. However, the doped polymers are sensitive to air and moisture thereby making them unattractive for practical use. In addition to semiconducting behavior, polysilanes exhibit photoconductivity and appear suitable for electrophotography (qv) (125—127). Polysdanes have also been found to exhibit nonlinear optical properties (94,128). 

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