| Titre : |
Carbon nanotube conductive networks through the double percolation concept in polymer systems |
| Type de document : |
texte imprimé |
| Auteurs : |
A. Abbasi, Auteur ; A. Derdouri, Auteur ; Pierre J. Carreau, Auteur |
| Année de publication : |
2014 |
| Article en page(s) : |
p. 13-27 |
| Note générale : |
Bibliogr. |
| Langues : |
Anglais (eng) |
| Catégories : |
Butylène téréphtalate cyclique
Conduction électrique
Matériaux hybrides
Matières plastiques -- Moulage par micro-injection
Nanotubes de carbone à parois multiplesUn nanotube de carbone multifeuillet est constitué de plusieurs feuillets de graphènes enroulés les uns autour des autres. Il existe deux modèles pour décrire la structure des nanotubes multifeuillets :
- le modèle poupée russe: les plans de graphène sont arrangés en cylindres concentriques ;
- le modèle parchemin: un seul feuillet de graphène est enroulé sur lui-même, comme une feuille de papier.
Percolation
Polybutylène téréphtalate
Polypropylène
|
| Index. décimale : |
668.4 Plastiques, vinyles |
| Résumé : |
We investigated the electrical conductivity and percolation behavior of binary and ternary nanocomposites based on multiwalled carbon nanotubes (MWCNs) using polypropylene (PP) and a blend of PP with cyclic butylene terephthalate (CBT). The nanocomposites were prepared by diluting a commercial 20 %wtMWCNT PP masterbatch using optimized melt-mixing conditions. The concentration of carbon nanotubes in the diluted PP samples was as low as 0.5 % and as high as 15 % in weight. For the PP/CBT blend CBT concentration was varied up to 40 %wt while the loading of CNT was from 0 to 5 %wt. SEM and TEM techniques were used to examine the quality of the dispersion and the formation of nanotube networks within the polymer matrix. TEM and Raman spectroscopy results showed that for the diluted PP/MWCNT composites the nanotubes are well aligned in samples obtained the microinjection molding process, although the level of alignment is less with crystalline PP than in an amorphous matrix such as polycarbonate (PC). FTIR and XRD results revealed that the orientation of both polymer chains and crystals decreased with the incorporation of nanotubes into PP. The electrical conductivity was also significantly altered by the nanotube alignment in a PP matrix, as was previously observed for PC/MWCNT composites; the conductivity decreased and the percolation threshold rose in highly sheared samples; however, the presence of a crystalline phase improved the conductivity even for high shear conditions through the phenomenon of double percolation threshold. This last concept refers to the requirement that the filler-rich phase be continuous and conductive and not to the existence of two percolation thresholds at two different CNT concentrations. The electrical conductivity of PP/CBT blends was also improved through a double percolation that is the basic requirement for the conductivity of the ternary nanocomposites. |
| Note de contenu : |
- EXPERIMENTAL : Materials - Nanocomposite preparation and molding - Morphological characterization - Nanotube alignment - Polymer chain and crystal orientation - Rheological measurements
- RESULTS : PP nanocomposites - PP/CBT blend nanocomposites |
| DOI : |
10.3139/217.2778 |
| En ligne : |
https://drive.google.com/file/d/1ZJZlKx49qryLnfqR7g8IQdi6ph2N2o-a/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=20571 |
in INTERNATIONAL POLYMER PROCESSING > Vol. XXIX, N° 1 (03/2014) . - p. 13-27
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Carbon nanotube conductive networks through the double percolation concept in polymer systems in INTERNATIONAL POLYMER PROCESSING, Vol. XXIX, N° 1 (03/2014)
