Morphology and electrical conduction

CORRELATION OF MORPHOLOGY AND ELECTRICAL CONDUCTION IN NANOSTRUCTURED PERYLENE PIGMENT FILMS... 

Surface morphology and electrical conduction in laser beam deposited perylene based thin films were investigated. It is found that the peak-to-peak value of the surface relief significantly increases with an increase of the substrate temperature at the deposition. Measuring of electrical properties by cyclic thermal desorption method shows that the hopping conductivity mechanism is realized in the films. The conductivity is intrinsic or impurity depending on the concentration of the adsorbed oxygen. 

Catalytic studies conducted on CNT- or CNF-based systems have shown encouraging results in terms of activity and selectivity. In particular, high selectivity has been obtained on catalytic systems displaying different metal-support interaction and/or charge transfer phenomena than those evidenced on other supports, such as activated carbon or alumina. High activity values arise from the mesoporous nature of this support, which avoids mass transfer limitations. For electrocatalysis, which constitutes an important field of application, the combination of specific support morphology and electrical conductivity often allows us to reach high electrocatalytic activity. 

Yui, H., Wu, G., Sano, H., Sumita, M., and Kino, K. 2006. Morphology and electrical conductivity of injection-molded polypropylene/carbon black composites with addition of high-density polyethylene. Polymer 47 3599-3608. 

In the present work, we used polyaniline (PANI)/polyacrylonitrile (PAN) blend to form a nonwoven mat. The PANI exists in a large number of intrinsic redox states. The half oxidized emeraldine base is the most stable and widely investigated state in the PANI family that can be dissolved in N-methyl-2 pyrohdon (NMP). The polyaniline emeraldine base (PANIEB)/polyacrilonitrile blend solution in NMP was prepared and then it was electrospun with different blending ratio. The fibers diameter, fibers morphology, and electrical conductivity of the mats were analyzed and discussed. 

M. Aldissi, Thesis, Polymerization of Acetylene with New Cata ts, New Doping Agents, Morphology and Electrical Conductivity of the Doped Polyacetylene Filins , Montpellier, 1981. 

Mo doping can be performed by a solid-state reaction including ball milling and heat-treatment. The macroscopic morphology and electrical conductivity of fhe doped samples is enhanced, and the cooperative actions of Mo... 

I. L. Hoiser, A. S. Vaughan, D. Patel, S. L. Sutton and S. G. Swingler, Morphology and electrical conductivity in polyaniline/ polyolefin blends. Transactions on Dielectrics and Electrical Insulation 8,698-704 (2001). 

In many composites, conducting fillers (carbon black, carbon nanotubes, or metal nanoparticles) are added to make material conductive. The relationship between composite morphology and electrical conductivity has been studied extensively, especially in the context of carbon black filled polymers [156-162]. It is well known that the dependence of conductivity on the loading of conductive filler, percolation theory there is some threshold filler loading below which there is no conductive pathway through the system and conductivity is zero above the threshold, conductivity grows very rapidly as ... 

Although there is no consistent explanation of the relationship between organic polymer morphology and electrical properties,51 amorphous structures are generally preferred over a crystalline structure. An experiment was conducted to study the structure of the fdm deposited using an inert carrier gas. The PNT-N... 

Jun, Z., Hou, H., Schaper, A., Wendorff, J.H., and Greiner, A., 2003. Poly-L-lactide nanofibers by electrospinning influence of solution viscosity and electrical conductivity on fiber diameter and fiber morphology, e-Polymers, paper 9. Available at http //www. e-polymers.org/journal/abstract.cfm.abstractld=401 (accessed September 17, 2007). 

Figure 17.6. Generalized comparison of phase separated blends comprising an electrically conducting polymer as a minor constituent. Normal nucleation and growth yields non-conductive blends micellar-type morphology yields electrical conductivity [Heeger, 1993].

The intractability of the early preparations of polyacetylene has severely hampered the establishment of clear-cut relationships between structure, morphology and (electrical) properties. An early example of an integrated approach to structure-property relations is a paper by Haberkom et al. [24], From a combination of x-ray data with NMR and IR investigations, these authors have found a relationship between the content of sp defects and crystallinity in polyacetylene prepared by the Shirakawa, Luttinger and other methods. Such defects are apparently expelled to the amorphous phase. The authors find a correlation with conductivity in both undoped and iodine-doped samples. 

Flow rate is the main parameter affecting the size and morphology of particles. Several studies have shown that the particle diameter can be controlled by flow rate and electrical conductivity. Ganan-Calvo proposed a theoretical model that reasonably agrees with the experimental results ... 

Liu et at fabricated the well-defined carboxylated CNTs/PPy composite hollow microspheres with near xmiform particle size of 1.4 pm via chemical oxidative interfacial polymerization of Py in the presence of the carboxylated carbon nanotubes (CNT-COOH) for the first time (Figure 8.1) [33]. It was found that the presence of the carboxylated CNTs greatly improved their morphological, thermal, and electrical conductive properties. The cycling stability as electrode materials for supercapacitors had been evidently improved by introducing the CNT-COOH, although the presence of the CNT-COOH had slightly enhanced their SC. 

Haidar I, Biswas M, Nayak A, Ray SS. Morphological, dielectric and electrical conductivity characteristics of clay-containing nanohybrids of poly(n-vinyl carbazole) and polypyrrole. J Nanosci Nanotechnol 2012 12(10) 7841-8. 

In situ polymerization to prepare immiscible blends was pioneered by Watkins and McCarthy [108], stimulating other researchers to apply this methodology to prepare novel polymer blends [109-112], fiber-reinforced composite materials[39], and electrically conducting composites [66, 67, 113-116]. Polymer blends produced in this manner include polystyrene/poly(vinyl chloride) [117, 118], polysty-rene/PET [119], nanometer-dispersed polypropylene/polystyrene interpenetrating networks [120], polypropylene/polystyrene [121] and polyethylene/polystyrene [122]. The resultant polymer blend may have a unique morphology compared to the traditionally prepared counterpart (if it is feasible to prepare such a blend via conventional procedures) and therefore demands a thorough investigation. 

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