Search results for " CNT"

Simulations on the mechanism of CNT bundle growth upon smooth and nanostructured Ni as well as θ-Al2O3 catalysts

2011

Abstract In the current study, we have performed ab initio DFT calculations on the gradually growing 2D periodic models of capped single-wall carbon nanotubes (SW CNTs) upon their perpendicular junctions with the Ni(111) substrate, in order to understand the peculiarities of the initial stage of their growth on either smooth or nanostructured catalytic particles. Appearance of the adsorbed carbon atoms upon the substrate follows from the dissociation of CVD hydrocarbon molecules, e.g., CH4: (CH4)ads → (CH)ads+3Hads and (CH)ads → Cads+Hads. (Since the effective growth of CNTs upon Ni nanoparticles occur inside the nanopores of amorphous alumina, we have also simulated analogous surface react…

Flexible Perfluoropolyethers-Functionalized CNTs-Based UHMWPE Composites: A Study on Hydrogen Evolution, Conductivity and Thermal Stability

2022

Flexible conductive composites based on ultra-high molecular weight polyethylene (UHMWPE) filled with multi-walled carbon nanotubes (CNTs) modified by perfluoropolyethers (PFPEs) were produced. The bonding of PFPE chains, added in 1:1 and 2:1 weight ratios, on CNTs influences the dispersion of nanotubes in the UHMWPE matrix due to the non-polar nature of the polymer, facilitating the formation of nanofillers-rich conductive pathways and improving composites’ electrical conductivity (two to five orders of magnitude more) in comparison to UHMWPE-based nanocomposites obtained with pristine CNTs. Electrochemical atomic force microscopy (EC-AFM) was used to evaluate the morphological changes dur…

Statistical analysis of the performances of PC/CNTs nanocomposites

2013

Statistical analysis of mechanical and dynamic-mechanical properties of PC/CNTs nanocomposites.

2013

Using matrix-assisted laser deposition/ionization time-of-flight mass spectrometry for the characterization of fucntionalized carbon nanotubes

2013

Melt-spun conductive fibers containing functionalized CNTs

2013

Multifunctional fibers based on polyamide 6 and plasma functionalized carbon nanotubes.

2013

Rheological behaviour of ultrahigh molecular weight polyethylene/functionalized-MWCNTs nanocomposites

2013

Mechanical Performance of CNT Fibres

2014

The initial strength hype over carbon nanotubes arose from predictions of the strength of individual graphene layers, encouraged by measurements of individual MWCNTs and SWCNT bundles in AFM. The challenge for fibres composed of carbon nanotubes (CNTs) is to translate the impressive properties of the individual carbon nanotubes into the fibres. Yarn-like fibres composed of carbon nanotubes made by the direct spinning process have been used as the subject of this study. There have been occasional observations of strengths greater than 5 N/tex, which have served to maintain the enthusiasm for on-going developments. Here, we will re-examine those reports in the context of the response of nanot…

Sonication-Induced Modification of Carbon Nanotubes: Effect on the Rheological and Thermo-Oxidative Behaviour of Polymer-Based Nanocomposites.

2018

The aim of this work is the investigation of the effect of ultrasound treatment on the structural characteristics of carbon nanotubes (CNTs) and the consequent influence that the shortening induced by sonication exerts on the morphology, rheological behaviour and thermo-oxidative resistance of ultra-high molecular weight polyethylene (UHMWPE)-based nanocomposites. First, CNTs have been subjected to sonication for different time intervals and the performed spectroscopic and morphological analyses reveal that a dramatic decrease of the CNT's original length occurs with increased sonication time. The reduction of the initial length of CNTs strongly affects the nanocomposite rheological behavio…