Effect of commercial and synthesized multiwalled carbon nanotubes on the electrical and thermal properties of polystyrene

Multiwalled carbon nanotubes (JMWCNTs) were synthesized using varying amounts of ferrocene catalyst (5-8 wt% of hydrocarbon precursor) and Jatropha seed oil as hydrocarbon precursor by chemical vapour deposition (CVD). The synthesized carbon material revealed highly entangled MWCNTs with some amount of amorphous carbon with very few defects. The range of product yield (compared to total weight of hydrocarbon source) was 20 - 28 % being highest in the case of nanotubes produced using 7 % (w/w) catalyst. The carbon nanotubes prepared by this method had diameter ranging from 50-100 nm and lengths from hundreds of nanometres to several micrometers. A decrease in diameter of nanotubes was observed along with increase in catalyst content upto 7% (w/w). The morphology of nanotubes synthesized was studied by high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM) and Raman spectroscopy. The effect of above prepared nanotubes and commercial multiwalled carbon nanotubes (CMWCNTs) on electrical, thermal, barrier and morphological properties of polystyrene was studied. Polystyrene nanocomposites prepared with JMWCNTs gave better improvement in properties as compared to nanocomposites prepared using CMWCNTs

Supplemental material for Refractive index matching for high light transmission composite systems

<p>Supplemental material for Refractive index matching for high light transmission composite systems by Erin Keaney, John Shearer, Artee Panwar and Joey Mead in Journal of Composite Materials</p

Effect of Molecular Weight on the Electrophoretic Deposition of Carbon Black Nanoparticles in Moderately Viscous Systems

Electrophoretic deposition from viscous media has the potential to produce in-mold assembly of nanoparticles onto three-dimensional parts in high-rate, polymer melt-based processes like injection molding. The effects of the media′s molecular weight on deposition behavior were investigated using a model system of carbon black and polystyrene in tetrahydrofuran. Increases in molecular weight reduced the electrophoretic deposition of the carbon black particles due to increases in suspension viscosity and preferential adsorption of the longer polystyrene chains on the carbon black particles. At low deposition times (≤5 s), only carbon black deposited onto the electrodes, but the deposition decreased with increasing molecular weight and the resultant increases in suspension viscosity. For longer deposition times, polystyrene codeposited with the carbon black, with the amount of polystyrene increasing with molecular weight and decreasing with greater charge on the polystyrene molecules. This deposition behavior suggests that use of lower molecular polymers and control of electrical properties will permit electrophoretic deposition of nanoparticles from polymer melts for high-rate, one-step fabrication of nano-optical devices, biochemical sensors, and nanoelectronics