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Conducting Phase (conducting + phase)
Selected AbstractsSynthesis and characterization of polyaniline doped with organic acidsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 8 2004Milind V. Kulkarni Abstract Spectroscopic [UV,visible and Fourier transform IR (FTIR)] and thermal properties of chemically synthesized polyanilines are found to be affected by varying the protonation media (acetic, citric, oxalic, and tartaric acid). The optical spectra show the presence of a greater fraction of fully oxidized insulating pernigraniline phase in polyaniline doped with acetic acid. In contrast, the selectivity in the formation of the conducting phase is higher in oxalic acid as a protonic acid media. The FTIR spectra of these polymers reveal a higher ratio of the relative intensities of the quinoid to benzenoid ring modes in acetic acid doped polyaniline. Scanning electron micrographs revealed a sponge-like structure derived from the aggregation of the small granules in acetic acid and oxalic acid doped polyaniline. A three-step decomposition pattern is observed in all the polymers, regardless of the protonic acid used for the doping. The second step loss related to the loss of dopant is found to be higher in the oxalic acid doped polymer. In accordance with these results the conductivity is also found to be higher in oxalic acid doped material. The temperature dependent conductivity measurements show the thermal activated behavior in all the polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2043,2049, 2004 [source] Electroactive composite systems containing high conductive polymer layers on poly(ethylene) porous films,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 9-10 2006G. K. Elyashevich Abstract New composite electroactive materials containing conducting polymers were elaborated by oxidative polymerization of aniline and pyrrole onto porous poly(ethylene) films. The morphology of the conducting phase on the surface of the composites was investigated by scanning electron microscopy. The influence of preparation method and porous support structure on electric and mechanical properties of the composite materials was studied. The correlation between the composites electroconductivity and the absorbance of electromagnetic radiation in the IR region was observed. It was found that gas separation and ion-exchange membrane properties of the composites strongly depend on their conductivity and content of conducting component. Copyright © 2006 John Wiley & Sons, Ltd. [source] Rich Phase Behavior in a Supramolecular Conducting Material Derived from an OrganogelatorADVANCED FUNCTIONAL MATERIALS, Issue 6 2009Josep Puigmartí-Luis Abstract Organic conducting fiber-like materials hold great promise for the development of nanowires that can act as connections in miniature electronic devices, as an alternative to inorganic nanometer scale structures. This article presents a conducting organic tetrathiafulvalene-based supramolecular material which possesses a rich phase behavior with different packing of the molecules in the different forms, evidenced by electron spin resonance (ESR) spectroscopy. The distinct phases of conducting nanofibers can be easily fabricated through the temperature control of their preparation process from a xerogel by doping with iodine vapors. A total of four conducting phases have been identified conclusively using ESR spectroscopy as the key analytical tool. Three of the phases show a good long-term stability and areas in which the I,V curves have ohmic behavior when studied by current sensing (conducting) AFM. They offer promise for applications where electrical nanometer scale connections are required. [source] On a hierarchy of models for electrical conduction in biological tissuesMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 7 2006M. Amar Abstract In this paper we derive a hierarchy of models for electrical conduction in a biological tissue, which is represented by a periodic array of period , of conducting phases surrounded by dielectric shells of thickness ,, included in a conductive matrix. Such a hierarchy will be obtained from the Maxwell equations by means of a concentration process , , 0, followed by a homogenization limit with respect to ,. These models are then compared with regard to their physical meaning and mathematical issues. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||