![]() ![]() Values of exact electrical polarizabilities for all chlorothiophenes have been calculated and listed in Table 4. Values of Polarizabilities of compounds containing halogen are used to interpret light scattering and intensities of vibrational Raman spectra. Since ionization potential energies are directly proportional to the electrochemical oxidation potentials of the compounds, it can be said that the electrochemical stability of monomers F and B are greater than other compounds. In polypyrroles, the mechanism of polymerization involves the formation of radical cations which react with another monomer to develop the polymeric structure (Figure 1). Thiophene is oxidized to form a conducting electro active polymer (CEP), with the best conductivity when it is created from α-α ' linkages. Ultrasonication has been used to improve the efficiency (improved yield, lowering of polymerization potentials) of electropolymerization process of polythiophene. Results show that when polymerization is carried out at 15-20☌, polymers with optimal properties will be obtained. The effect of temperature on polymerization process of thiophene has been investigated as well. Polythiophene has a solubility of 75% (w/w) in chloroform and a conductivity of 220 s cm -1. It has been recently shown that the attachment of a range of electron-donating or electron-withdrawing groups through a conjugated linker has a dramatic effect on polymerization potential and subsequent photovoltaic performance. The influence of water on polymerization process of thiophene as well as on the redox switching properties has been studied. Polythiophenes are normally produced from non aqueous media because the monomer is more soluble in them. Among intrinsic conducting polymers with conjugated double bonds, polythiophenes (PTHs) and related derivatives are suitable for commercial applications. The varieties of such studies have been reported in the literature that includes: surfactants, liquid crystals, polyelectrolytes, nano-wire seeds, thiophene oligomers, bulky organic dopants. There has been growing interest in research on conducting polymer nano structures (nano-rods, -tubes, -wires and -fibers) since they incorporate the advantages of organic conductors with low-dimensional systems and so create interesting physicochemical properties and potentially useful applications. ![]() The 2000 Nobel Prize in chemistry recognized the discovery of conducting polymers and over 25 years of progress in this field. ![]() Electrically-conducting polymers such as advanced materials and the new class of ' synthetic metals' have drawn high attention in the last years. ![]()
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