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Effect of the carbon nanotube surface characteristics on the conductivity and dielectric constant of carbon nanotube/poly(vinylidene fluoride) composites.

Carabineiro SA, Pereira MF, Pereira JN, Caparros C, Sencadas V, Lanceros-Mendez S - Nanoscale Res Lett (2011)

Bottom Line: Commercial multi-walled carbon nanotubes (CNT) were functionalized by oxidation with HNO3, to introduce oxygen-containing surface groups, and by thermal treatments at different temperatures for their selective removal.CNT/poly(vinylidene fluoride) composites were prepared using the above CNT samples, with different filler fractions up to 1 wt%.It was found that oxidation reduced composite conductivity for a given concentration, shifted the percolation threshold to higher concentrations, and had no significant effect in the dielectric response.

View Article: PubMed Central - HTML - PubMed

Affiliation: Universidade do Porto, Faculdade de Engenharia, Laboratório de Catálise e Materiais (LCM), LSRE/LCM - Laboratório Associado, Rua Dr, Roberto Frias, s/n, 4200-465 Porto, Portugal. sonia.carabineiro@fe.up.pt.

ABSTRACT
Commercial multi-walled carbon nanotubes (CNT) were functionalized by oxidation with HNO3, to introduce oxygen-containing surface groups, and by thermal treatments at different temperatures for their selective removal. The obtained samples were characterized by adsorption of N2 at -196°C, temperature-programmed desorption and determination of pH at the point of zero charge. CNT/poly(vinylidene fluoride) composites were prepared using the above CNT samples, with different filler fractions up to 1 wt%. It was found that oxidation reduced composite conductivity for a given concentration, shifted the percolation threshold to higher concentrations, and had no significant effect in the dielectric response.

No MeSH data available.


Related in: MedlinePlus

SEM images for the PVDF@ CNTox400 composites (for 0.2% CNTox400): (a) surface image showing the spherulitic microstructure of the polymer and (b) fracture image showing the dispersion of the CNT into the bulk of the polymeric matrix.
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Figure 3: SEM images for the PVDF@ CNTox400 composites (for 0.2% CNTox400): (a) surface image showing the spherulitic microstructure of the polymer and (b) fracture image showing the dispersion of the CNT into the bulk of the polymeric matrix.

Mentions: The morphology and fiber distribution of the composite samples were analyzed by SEM to evaluate the CNT dispersion in the polymeric matrix and determine how the composites influence the polymer crystallization microstructure. Figure 3 shows the SEM images for the PVDF/CNT composites. The main relevant microstructural feature of the composite is that the CNT are randomly distributed into the polymeric matrix. The spherulitic structure characteristic of the pure PVDF is still present in all the composites samples [12,18].


Effect of the carbon nanotube surface characteristics on the conductivity and dielectric constant of carbon nanotube/poly(vinylidene fluoride) composites.

Carabineiro SA, Pereira MF, Pereira JN, Caparros C, Sencadas V, Lanceros-Mendez S - Nanoscale Res Lett (2011)

SEM images for the PVDF@ CNTox400 composites (for 0.2% CNTox400): (a) surface image showing the spherulitic microstructure of the polymer and (b) fracture image showing the dispersion of the CNT into the bulk of the polymeric matrix.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211369&req=5

Figure 3: SEM images for the PVDF@ CNTox400 composites (for 0.2% CNTox400): (a) surface image showing the spherulitic microstructure of the polymer and (b) fracture image showing the dispersion of the CNT into the bulk of the polymeric matrix.
Mentions: The morphology and fiber distribution of the composite samples were analyzed by SEM to evaluate the CNT dispersion in the polymeric matrix and determine how the composites influence the polymer crystallization microstructure. Figure 3 shows the SEM images for the PVDF/CNT composites. The main relevant microstructural feature of the composite is that the CNT are randomly distributed into the polymeric matrix. The spherulitic structure characteristic of the pure PVDF is still present in all the composites samples [12,18].

Bottom Line: Commercial multi-walled carbon nanotubes (CNT) were functionalized by oxidation with HNO3, to introduce oxygen-containing surface groups, and by thermal treatments at different temperatures for their selective removal.CNT/poly(vinylidene fluoride) composites were prepared using the above CNT samples, with different filler fractions up to 1 wt%.It was found that oxidation reduced composite conductivity for a given concentration, shifted the percolation threshold to higher concentrations, and had no significant effect in the dielectric response.

View Article: PubMed Central - HTML - PubMed

Affiliation: Universidade do Porto, Faculdade de Engenharia, Laboratório de Catálise e Materiais (LCM), LSRE/LCM - Laboratório Associado, Rua Dr, Roberto Frias, s/n, 4200-465 Porto, Portugal. sonia.carabineiro@fe.up.pt.

ABSTRACT
Commercial multi-walled carbon nanotubes (CNT) were functionalized by oxidation with HNO3, to introduce oxygen-containing surface groups, and by thermal treatments at different temperatures for their selective removal. The obtained samples were characterized by adsorption of N2 at -196°C, temperature-programmed desorption and determination of pH at the point of zero charge. CNT/poly(vinylidene fluoride) composites were prepared using the above CNT samples, with different filler fractions up to 1 wt%. It was found that oxidation reduced composite conductivity for a given concentration, shifted the percolation threshold to higher concentrations, and had no significant effect in the dielectric response.

No MeSH data available.


Related in: MedlinePlus