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Surface Resistivity (surface + resistivity)
Selected AbstractsSelf-Organized Single-Walled Carbon Nanotube Conducting Thin Films with Honeycomb Structures on Flexible Plastic FilmsADVANCED FUNCTIONAL MATERIALS, Issue 2 2009Nobuo Wakamatsu Abstract Complex 1, synthesized from anionic shortened single-walled carbon nanotubes and cationic ammonium lipid dissolved in organic solvents, is cast on pretreated transparent flexible poly(ethylene terephthalate) (PET) films under a higher relative humidity to form thin films with self-organized honeycomb structures. The cell sizes are controllable by changing the experimental conditions. The lipid, which is the cationic part of complex 1, is easily removed by a simple ion-exchange method, while maintaining the basic honeycomb structures. After the ion exchange, the nanotube honeycomb films on PET with thinner skeletons exhibit a dramatic decrease in the surface resistivity from insulating to conducting. Carbon nanotubes with honeycomb structures formed by the self-organization on flexible polymer films are useful in many areas of nanoscience and technology including nanomaterials, nanoelectronics, nanodevices, catalysts, sensors, and so on. [source] Plasma-induced graft polymerization of poly(ethylene glycol) on poly(methyl methacrylate) surfaces for improving antistatic propertyJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2010Yanlin Wei Abstract Ar plasma-induced graft polymerization of poly(ethylene glycol) (PEG) on Ar plasma pretreated poly(methyl methacrylate) (PMMA) surfaces was carried out to improve the antistatic properties. The surface composition and microstructure of the PEG-grafted PMMA surfaces from plasma induction were characterized by attenuated total reflectance Fourier transfer infrared (ATR-FTIR) spectroscopy, water contact angles (CA), and atomic force microscopy (AFM) measurements. The measurements revealed that the antistatic properties can be remarkably improved with the surface resistivity of PEG-grafted PMMA surface decreasing significantly by 3,6 orders of magnitude, with the optimum condition for polymerization grafted onto the Ar plasma pretreated PMMA surface being 40 W for RF power and 3 min for glow discharge time. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Nonlinear surface electrical resistivity of graphite,polyurethane composite filmsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2007Ganesh K. Kannarpady Abstract In this article, we study the surface resistivity of graphite,polyurethane composites using voltage,current characteristics. The evolution of the percolation network of graphite in polyurethane is qualitatively studied using optical micrographs. As expected, the surface resistivity decreases as a function of graphite concentration. In particular, the surface resistivity of the 69% graphite,polyurethane composite is about four orders of magnitude lower than the surface resistivity of the 27% graphite,polyurethane composite. The electrical resistivity of the composite is found to be highly nonlinear with respect to an increasing voltage at a low graphite weight fraction. On the other hand, the nonlinearity is significantly milder at higher weight fractions. The reasons behind the nonlinearity are discussed. Very preliminary studies indicate that very low weight fractions of single wall carbon nanotubes (e.g. 2.5%) are sufficient to generate electrical conductivities comparable to much higher loading fractions (, 60% and higher) of the heavier graphite particles. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [source] Effect of ATH content on electrical and aging properties of EVA and silicone rubber blends for high voltage insulator compoundJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2007M. A. Pradeep Abstract The effect of trihydrated alumina (Al2O3, 3H2O) (ATH) filler in ethylene-vinyl acetate copolymer (EVA) and silicone rubber blends was investigated by performing a series of laboratory experiments to simulate different natural aging conditions. Samples with varying ATH content in a 50-50 blend of EVA and polydimethylsiloxane (PDMS) (silicone rubber, MQ) were tested to investigate the tracking resistance, resistance to UV radiation, corona, heat, and water immersion. Changes in surface resistivity, volume resistivity, and hydrophobic characteristics were evaluated for different compounds having ATH content. These exercises were mainly carried out to optimize the filler level. In immersed condition the water absorption increases with ATH content. The recovery of hydrophobicity, after aging by heat, is appreciable at higher ATH levels, than at lower ATH levels. The tracking and erosion resistance decrease as ATH content increases. When compounds containing different ATH content were subjected to corona treatment, the samples with higher ATH levels exhibited better results. All samples changed their color to a darker shade and there was an increase in the hydrophobicity, when subjected to UV radiation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3505,3516, 2007 [source] Use of Single-Walled Carbon Nanotubes as Reinforcing Fillers in UV-Curable Epoxy SystemsMACROMOLECULAR MATERIALS & ENGINEERING, Issue 8 2008Marco Sangermano Abstract CNT were dispersed in an epoxy matrix and cured by means of UV light. An increase on elastic modulus and Tg values was measured by DMTA analysis and attributed to the constraint effect of CNT on polymer chain mobility. Excellent scratch resistant coatings characterized by high critical load, small cracks and high recovery were obtained in the presence of a very low CNT content (0.025 wt.-%). TEM analysis showed some isolated CNT and some cluster agglomerations of size of about 250 nm. It was shown that it was possible to decrease the surface resistivity of the cured samples by three orders of magnitude in the presence of 0.1 wt.-% of SWCNT content. [source] Development of a packaging material using non-bleed-type antistatic ionomerPACKAGING TECHNOLOGY AND SCIENCE, Issue 5 2004Nobuyuki Maki Abstract Generally, plastics and plastic films are low in moisture absorption and high in electric insulation. They are inherently vulnerable to static charge build-up, which can result in a variety of problems. We have developed a functional packaging material to solve these static problems, by using a potassium salt of ethylene ionomer, which is a non-bleed-type antistatic agent. Good antistatic performance was shown by evaluating a variety of electric characteristics (e.g. the static decay time, ash test and saturated electrostatic charge and half-life) and surface resistivity. In addition, antistatic performance was achieved on the mLLDPE (non-treated) side in a multilayer structure. This means that the use of potassium ionomer on any layers in a multilayer structure provides antistatic performance, leading to the expectation of developing a wide variety and diversity of packaging materials. Copyright © 2004 John Wiley & Sons, Ltd. [source] In-situ synthesis of transparent and conductive carbon nanotube networksPHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 4 2007Márcio D. Lima Abstract A method for the production of transparent carbon nanotube networks (CNTNs) over transparent substrates was developed. In this method, CNTNs were grown directly in the target surface by applying the catalyst in specific zones of the substrate through lithographic techniques. The networks can be also transferred from the original substrate to other surfaces. The newly grown carbon nanotubes have a very high aspect ratio (>50000). Thus far, networks with an optical transmittance of 94% at 550 nm and a surface resistivity of 3.6 k,/sq have been produced. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||