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Inorganic nanotubes reinforced polyvinylidene fluoride composites as low-cost electromagnetic interference shielding materials.

Eswaraiah V, Sankaranarayanan V, Ramaprabhu S - Nanoscale Res Lett (2011)

Bottom Line: Homogeneous distribution of f-MWCNTs and MNTs in PVDF matrix were confirmed by field emission scanning electron microscopy.The addition of 2 wt.% of MNTs (2 wt.%, f-MWCNTs) to PVDF matrix results in an increase in the electrical conductivity from 10-16S/m to 4.5 × 10-5S/m (3.2 × 10-1S/m).EMI SE of approximately 20 dB has been obtained with the addition of 5 wt.% MNTs-1 wt.% f-MWCNTs to PVDF in comparison with EMI SE of approximately 18 dB for 7 wt.% of f-MWCNTs indicating the potential use of the present MNT/f-MWCNT/PVDF composite as low-cost EMI shielding materials in X-band region.

View Article: PubMed Central - HTML - PubMed

Affiliation: Alternative Energy and Nanotechnology Laboratory (AENL), Nano Functional Materials, Technology Centre (NFMTC), Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India. ramp@iitm.ac.in.

ABSTRACT
Novel polymer nanocomposites comprising of MnO2 nanotubes (MNTs), functionalized multiwalled carbon nanotubes (f-MWCNTs), and polyvinylidene fluoride (PVDF) were synthesized. Homogeneous distribution of f-MWCNTs and MNTs in PVDF matrix were confirmed by field emission scanning electron microscopy. Electrical conductivity measurements were performed on these polymer composites using four probe technique. The addition of 2 wt.% of MNTs (2 wt.%, f-MWCNTs) to PVDF matrix results in an increase in the electrical conductivity from 10-16S/m to 4.5 × 10-5S/m (3.2 × 10-1S/m). Electromagnetic interference shielding effectiveness (EMI SE) was measured with vector network analyzer using waveguide sample holder in X-band frequency range. EMI SE of approximately 20 dB has been obtained with the addition of 5 wt.% MNTs-1 wt.% f-MWCNTs to PVDF in comparison with EMI SE of approximately 18 dB for 7 wt.% of f-MWCNTs indicating the potential use of the present MNT/f-MWCNT/PVDF composite as low-cost EMI shielding materials in X-band region.

No MeSH data available.


Related in: MedlinePlus

DC electrical conductivity of the MNTs/PVDF and f-MWCNTs/PVDF composites.
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Figure 9: DC electrical conductivity of the MNTs/PVDF and f-MWCNTs/PVDF composites.

Mentions: Electrical conductivity is of utmost importance for effective EMI shielding material. As shown in the Figure 9, the conductivity of the PVDF is about 10-16S/m. As the concentration of the MNTs increases in the PVDF matrix, electrical conductivity increases, and it follows percolation behavior. Conductivity of the 1 wt.% MNTs/PVDF composite was found to be approximately 10-6S/m, which indicates that there is a drastic improvement in electrical conductivity. An increase of about ten orders of magnitude of electrical conductivity was observed which can be attributed to the high aspect ratio and efficient dispersion of the MNTs in the PVDF matrix. Similar trend is observed in the case of electrical conductivity of the f-MWCNTs/PVDF composites as shown in Figure 9b. The possible mechanism for the increment in the electrical conductivity of the composites can be the tunneling effect of the electrons from one nanotube to the other. The effect of f-MWCNTs content on the electrical conductivity of the MNTs/PVDF composites was studied. Incorporation of 1 wt.% f-MWCNTs in 5 wt.% MNT/PVDF composites increases the conductivity from 10-5S/m to approximately 10-1S/m which can be attributed to the high aspect ratio, homogeneous dispersion, and high electrical conducting nature of the f-MWCNTs.


Inorganic nanotubes reinforced polyvinylidene fluoride composites as low-cost electromagnetic interference shielding materials.

Eswaraiah V, Sankaranarayanan V, Ramaprabhu S - Nanoscale Res Lett (2011)

DC electrical conductivity of the MNTs/PVDF and f-MWCNTs/PVDF composites.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211184&req=5

Figure 9: DC electrical conductivity of the MNTs/PVDF and f-MWCNTs/PVDF composites.
Mentions: Electrical conductivity is of utmost importance for effective EMI shielding material. As shown in the Figure 9, the conductivity of the PVDF is about 10-16S/m. As the concentration of the MNTs increases in the PVDF matrix, electrical conductivity increases, and it follows percolation behavior. Conductivity of the 1 wt.% MNTs/PVDF composite was found to be approximately 10-6S/m, which indicates that there is a drastic improvement in electrical conductivity. An increase of about ten orders of magnitude of electrical conductivity was observed which can be attributed to the high aspect ratio and efficient dispersion of the MNTs in the PVDF matrix. Similar trend is observed in the case of electrical conductivity of the f-MWCNTs/PVDF composites as shown in Figure 9b. The possible mechanism for the increment in the electrical conductivity of the composites can be the tunneling effect of the electrons from one nanotube to the other. The effect of f-MWCNTs content on the electrical conductivity of the MNTs/PVDF composites was studied. Incorporation of 1 wt.% f-MWCNTs in 5 wt.% MNT/PVDF composites increases the conductivity from 10-5S/m to approximately 10-1S/m which can be attributed to the high aspect ratio, homogeneous dispersion, and high electrical conducting nature of the f-MWCNTs.

Bottom Line: Homogeneous distribution of f-MWCNTs and MNTs in PVDF matrix were confirmed by field emission scanning electron microscopy.The addition of 2 wt.% of MNTs (2 wt.%, f-MWCNTs) to PVDF matrix results in an increase in the electrical conductivity from 10-16S/m to 4.5 × 10-5S/m (3.2 × 10-1S/m).EMI SE of approximately 20 dB has been obtained with the addition of 5 wt.% MNTs-1 wt.% f-MWCNTs to PVDF in comparison with EMI SE of approximately 18 dB for 7 wt.% of f-MWCNTs indicating the potential use of the present MNT/f-MWCNT/PVDF composite as low-cost EMI shielding materials in X-band region.

View Article: PubMed Central - HTML - PubMed

Affiliation: Alternative Energy and Nanotechnology Laboratory (AENL), Nano Functional Materials, Technology Centre (NFMTC), Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India. ramp@iitm.ac.in.

ABSTRACT
Novel polymer nanocomposites comprising of MnO2 nanotubes (MNTs), functionalized multiwalled carbon nanotubes (f-MWCNTs), and polyvinylidene fluoride (PVDF) were synthesized. Homogeneous distribution of f-MWCNTs and MNTs in PVDF matrix were confirmed by field emission scanning electron microscopy. Electrical conductivity measurements were performed on these polymer composites using four probe technique. The addition of 2 wt.% of MNTs (2 wt.%, f-MWCNTs) to PVDF matrix results in an increase in the electrical conductivity from 10-16S/m to 4.5 × 10-5S/m (3.2 × 10-1S/m). Electromagnetic interference shielding effectiveness (EMI SE) was measured with vector network analyzer using waveguide sample holder in X-band frequency range. EMI SE of approximately 20 dB has been obtained with the addition of 5 wt.% MNTs-1 wt.% f-MWCNTs to PVDF in comparison with EMI SE of approximately 18 dB for 7 wt.% of f-MWCNTs indicating the potential use of the present MNT/f-MWCNT/PVDF composite as low-cost EMI shielding materials in X-band region.

No MeSH data available.


Related in: MedlinePlus