Carbon nanotubes mechanical properties

Keywords ceramic matrix composites, carbon nanotubes, mechanical properties, sintering, glasses... 

The yield strengths of defect-free SWNTs may be higher than that measured for Bacon s scroll structures, and measurements on defect-free carbon nanotubes may allow the prediction of the yield strength of a single, defect-free graphene sheet. Also, the yield strengths of MWNTs are subject to the same limitations discussed above with respect to tube slippage. All the discussion here relates to ideal nanotubes real carbon nanotubes may contain faults of various types that will influence their properties and require experimental measurements of their mechanical constants. 

The direct linking of carbon nanotubes to graphite and the continuity in synthesis, structure and properties between carbon nanotubes and vapor grown carbon fibers is reviewed by the present leaders of this area, Professor M. Endo, H. Kroto, and co-workers. Further insight into the growth mechanism is presented in the article by Colbert and Smalley. New synthesis methods leading to enhanced production... 

The force effect is applicable to investigation of the mechanical properties of nanomaterials [28, 29]. We measured TERS spectra of a single wall carbon nanotube (SWCNT) bundle with a metallic tip pressing a SWCNT bundle [28]. Figure 2.13a-e show the Raman spectra of the bundle measured in situ while gradually applying a force up to 2.4 nN by the silver-coated AFM tip. Raman peaks of the radial breathing... 

Another interesting type of novel carbons applicable for supercapacitors, consists of a carbon/carbon composite using nanotubes as a perfect backbone for carbonized polyacrylonitrile. Multiwalled carbon nanotubes (MWNTs), due to their entanglement form an interconnected network of open mesopores, which makes them optimal for assuring good mechanical properties of the electrodes while allowing an easy diffusion of ions. 

CNTs have been one of the most actively studied electrode materials in the past few years due to their unique electronic and mechanical properties. From a chemistry point of view, CNTs are expected to exhibit inherent electrochemical properties similar to other carbon electrodes widely used in various electrochemical applications. Unlike other carbon-based nanomaterials such as C60 and C70 [31], CNTs show very different electrochemical properties. The subtle electronic properties suggest that carbon nanotubes will have the ability to mediate electron transfer reactions with electroactive species in solution when used as the electrode material. Up to now, carbon nanotube-based electrodes have been widely used in electrochemical sensing [32-35], CNT-modified electrodes show many advantages which are described in the following paragraphs. 

CNT-doped conducting polymers possess improved mechanical, chemical, and optical properties. They also provide a simple strategy for making aligned CNTs. The disappearance of the characteristic peaks of carbon nanotubes in the FTIR spectrum of polymer/CNT composite films is normally an indication of perfect enwrapping of CNTs with the deposited conducting polymer [162, 163], Zhang et al. [40] have studied the... 

Coleman, J. N., Khan, U., Blau, W. J., and Gunko, Y. K. 2006. Small but strong A review of the mechanical properties of carbon nanotube-polymer composites. Carbon 44 1624-52. 

The mechanical properties of the inorganic nanotubes have only been investigated to a relatively small extent. The Young s modulus of multiwall BN nanotubes was measured using the vibrational method within a TEM (17) and was found to be 1.2 TPa, which is comparable to the values measured for carbon nanotubes. The Young s modulus of the b-P nanotubes was calculated (88a). The observed value, 300 GPa, is some 25% of the Young s modulus of carbon nanotubes. The Poisson ratio of b-P nanotubes was calculated to be 0.25 in this work. 

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