Carbon Nanotube Dispersion (carbon + nanotube_dispersion)

Distribution by Scientific Domains
Polymers and Materials Science100%

Selected Abstracts

A General Strategy to Disperse and Functionalize Carbon Nanotubes Using Conjugated Block Copolymers

ADVANCED FUNCTIONAL MATERIALS, Issue 3 2009
Jianhua Zou
Abstract A general strategy to disperse and functionalize pristine carbon nanotubes in a single-step process is developed using conjugated block copolymers. The conjugated block copolymer contains two blocks: a conjugated polymer block of poly(3-hexylthiophene), and a functional non-conjugated block with tunable composition. When the pristine carbon nanotubes are sonicated with the conjugated block copolymers, the poly(3-hexylthiophene) blocks bind to the surface of de-bundled carbon nanotubes through non-covalent ,,, interactions, stabilizing the carbon nanotube dispersion, while the functional blocks locate at the outer surface of carbon nanotubes, rendering the carbon nanotubes with desired functionality. In this paper, conjugated block copolymers of poly(3-hexylthiophene)- b -poly(methyl methacrylate), poly(3-hexylthiophene)- b -poly(acrylic acid), and poly(3-hexylthiophene)- b -poly(poly(ethylene glycol) acrylate) are used to demonstrate this general strategy. [source]

Influence of carbon nanotube dispersion on the mechanical properties of phenolic resin composites

POLYMER COMPOSITES, Issue 2 2010
R.B. Mathur
Despite the much touted mechanical properties of carbon nanotubes, composites reinforced with nanotubes have failed to achieve mechanical properties which rival those present in conventional fiber reinforced polymer composites. This article describes an attempt to bridge this gap. Multi-walled carbon nanotubes (MWCNT) were synthesized using a chemical vapor deposition method and were dispersed in phenolic resin by both the wet and dry dispersion techniques before molding into composite bars (50 × 5 × 3 mm3). Although no improvement in the mechanical properties of the MWCNT/phenolic composites was observed over the neat resin value when wet mixing dispersion was employed, an improvement of nearly 158% (160 MPa as compared with 62 MPa for neat resin) was achieved in 5 vol% MWCNT containing phenolic resin prepared by the dry mixing. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers [source]

Size-Dependence and Elasticity of Liquid-Crystalline Multiwalled Carbon Nanotubes,

ADVANCED MATERIALS, Issue 16 2008
Wenhui Song
Profound size-effects of liquid-crystalline microstructures of multiwalled carbon nanotube dispersions are reported. The figure shows that nanotubes behave like rigid rods in the case of a low aspect ratio; however, they behave as flexible beams that deform easily following the local orientation in a liquid crystalline field if they are thin and/or long with a relatively high aspect ratio. [source]

Analysis and measurement of carbon nanotube dispersions: nanodispersion versus macrodispersion

POLYMER INTERNATIONAL, Issue 10 2010
Micah J Green
Abstract Because of their unique mechanical, optical, thermal and electrical properties, carbon nanotubes (CNTs) form the basis for a wide variety of multifunctional devices and materials; many of these applications require that CNTs be dispersed and processed in liquids such as organic solvents, polymer melts or surfactant solutions. One of the most problematic issues affecting the CNT research community is the lack of standards and uniform characterization methods for CNT dispersion. A 2005 NASA-NIST workshop aimed to address this issue and made a clear distinction between ,nanodispersion' of individual CNTs and ,macrodispersion' of CNT bundles. Unfortunately, this distinction has yet to percolate through the CNT dispersion literature. The present article seeks to elucidate and commend these concepts, identify the situations where this difference is most critical, note some scenarios where these concepts have been underutilized and posit experimental and computational characterization methods for quantifying the degree of nanodispersion. Particular attention is devoted to the controversial claims of complete nanodispersion and how such claims may be verified. Copyright © 2010 Society of Chemical Industry [source]