Nanotubes types

In order to obtain accurate estimates of adsorption energies, it is important to understand how H2 molecules are distributed in the lattice of each SWNT type. Specifically, for a given nanotube type and H2 loading, we must first determine the... 

Composite Nanotube type Nanotube cont. PVA mol weight Y/Y p g/g p Reference... 

It comes out, that polymer network is a very specific ensemble of entities [II] in terms of classification in the introductory chapter of this book, it has been possible to transform some nanoeffects to macroscale. At the same time, as we shall see, it is expected to be liable to statistical, mechanical, and even quantum statistics treatment. Recent experiments with networks of nanotube type, as quantum wires capable of ballistic transfer of charge [12,13], can be reported as the extension of a such approach to carbon-carbon network. 

Obviously the strength of the interfacial bonding between the CNTs and the polymer matrix will have a major impact upon their ability to reinforce the composite. Wagner et al. [114] studied this issue by conducting experiments in which a MWNT, attached to an AFM tip, was embedded in a polymer and pulled out. The force versus pull-out length was recorded for a poly(ethylene-butene) matrix resulting in an interfacial shear strength of 47 MPa. This value is consistent with other measurements where estimates of 50 MPa for various nanotube types were recorded [12]. 

Figure 1.12 Three types of carbon nanotubes (a) armchair, (b) zigzag, and (c) chiral. The definition of nanotube types is according to the orientation perpendicular to the nanotube axis. (Figure from Ref. [82].)...

The use of organic nanofillers allows the reduction of the filler content required to achieve high thermal conductivity. In particular, multi-walled carbon nanotubes (MWCNTs), with their one-dimensional structure, high aspect ratio and superior thermal conductivity (3000 W/mK for an individual MWCNT and 200 W/mK for bulk MWCNTs at room temperature (Yang et al., 1991)) have recently attracted great attention in the scientific world. The influence of different carbon nanotube types, particle content, interfacial area, surface functionalization and aspect ratio on the electrical and thermal conductivity of epoxy resins has been investigated (Gojny et al., 2006). 

Under appropriate conditions, the oligomers made up of 2,6-diaminopyridine and 2,6-pyridinedicarboxylic acid oligoamides, such as the one shown in Figure 4(d), self-assemble into double helical structures. The diameter of the double helices formed by oligoamide foldamers is intermediate between those of DNA and Gramicidin D. These nanotube types can be considered as a barrel model and are discussed in the following section. 

Similar nanotube types were also prepared form peptide amphiphiles made of a hydrophilic head with one or two charged amino acids and a hydrophobic tail of four or more consecutive hydrophobic ones. Between the studied hydrophobic amino acids, alanine and valine produce more homogeneous and stable nanotubes than glycine, isoleucine, and leucine. On the other hand, lysine or histidine is preferred over arginine, possibly due to steric effects. The tubes are stabilized mainly by the hydrophobic effects similar to the LNTs, albeit the diameter is around an order of magnitude smaller. Unlike conventional surfactants. 

Within the huge amount of papers deahng with carbon nanotubes (CNTs or, simply NTs) that appeared in the literature since the seminal work by lijima [151] and exponentially increased in the following decades [152,153], porphyrin-decorated NT represent an important part, both with the single-walled (SWCNTs) and multiwalled (MWCNTs) carbon nanotube type. 

Polymer Characteristics Nanotube Type Preparation Steps Technique (wt%) (kn in s ) (°C) AT C C) ... 

Characteristics Nanotube Type Preparation Steps Technique (wt%)... 

Nanotube type Preparation approach Polymer/organic molecules Catalyst/ reagent References... 

Polymer or surfactant Nanotube type Preparation method References... 

A wide range of values for conductivity and percolation thresholds of CNT composites has been reported in the literature during the last decade, depending on the processing method, polymer matrix, and nanotube type. Recent review articles can be found in Refs [6,87,90]. In Table 10.2, selected research studies concerning the DC electrical properties of CNT-polymer composites are presented. Also, a comparison between the different types of polymeric matrices, CNTs type... 

The electrical conductivity of polymer-CNT composites can be explained by percolation theory. The conductivity depends upon the filler concentration (commonly named as percolation threshold). The choice of polymer, nanotube type and solvent used during synthesis all affect the percolation threshold. In addition to it the processing technique, mixing stresses applied during preparation, as well as the shaping procedure play imperative roles [15]. 

Single nanostructures pump probe microscopy experiments revealed energy relaxation pathways that are obscured by ensemble averaging. For example, understanding of the intrinsic optical properties of single wall carbon nanotubes (SWCNTs) has been previously hindered primarily by the broad distribution of semiconducting and metallic nanotube types in as-synthesized... 

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