Thermal Conductivity and Electrical Resistivity of Electrospun Polyacrylonitrile-Multi Wall Carbon Nanotubes Composite Carbon Nanofibers

Single filler polyurethane composites with carbon fibers (CFs) and multi-walled carbon nanotubes (MWNTs) were prepared by melt mixing methods and its thermal as well as electrical resistivity characteristics were investigated. The influences of fillers and mixing methods on thermal and electrical conductivity of CF/- and MWNT/polyurethane composites were investigated and the result shows that the addition of carbon fillers improved the thermal conductivity of the polyurethane composites. Higher filler concentration results in better thermal conductivity because better formation of thermally conductive networks along polymer matrix to ensure the thermal was conducted through the matrix and the network along the polymer composites. The presence of carbon additives improves the electrical resistivity of the materials as well. The present study revealed the potential of carbon as agent for better thermal and electrical conductivities and their properties depend strongly on the dispersion and distribution of the fillers in the polymer matrix.

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Experimental study on density, thermal conductivity, specific heat, and viscosity of water-ethylene glycol mixture dispersed with carbon nanotubes

Thermal Science ◽

10.2298/tsci141015028g ◽

2017 ◽

Vol 21 (1 Part A) ◽

pp. 255-265 ◽

Cited By ~ 10

Author(s):

Jayabalan Ganeshkumar ◽

Durai Kathirkaman ◽

Kandhaswamy Raja ◽

Vellisamy Kumaresan ◽

Ramalingam Velraj

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Ethylene Glycol ◽

Specific Heat ◽

Fold Increase ◽

Modified Model ◽

Multi Wall Carbon Nanotubes ◽

Conductivity Enhancement ◽

Mwcnt Concentration ◽

Nanoparticle Aggregates

This article presents the effect of adding multi wall carbon nanotubes (MWCNT) in water ? ethylene glycol mixture on density and various thermophysical properties such as thermal conductivity, specific heat and viscosity. Density of nanofluids was measured using standard volumetric flask method and the data showed a good agreement with the mixing theory. The maximum thermal conductivity enhancement of 11 % was noticed for the nanofluids with 0.9 wt. %. Due to lower specific heat of the MWCNT, the specific heat of the nanofluids decreased in proportion with the MWCNT concentration. The rheological analysis showed that the transition region from shear thinning to Newtonian extended to the higher shear stress range compared to that of base fluids. Viscosity ratio of the nanofluids augmented anomalously with respect to increase in temperature and about 2.25 fold increase was observed in the temperature range of 30 ? 40 ?C. The modified model of Maron and Pierce predicted the viscosity of the nanofluids with the inclusion of effect of aspect ratio of MWCNT and nanoparticle aggregates.

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Thermoelectric Properties of Carbon Nanotubes Added n-type CoSb3 Compound

MRS Proceedings ◽

10.1557/opl.2011.515 ◽

2011 ◽

Vol 1314 ◽

Cited By ~ 3

Author(s):

Takashi Itoh ◽

Masashi Tachikawa

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Electrical Resistivity ◽

Seebeck Coefficient ◽

Thermoelectric Properties ◽

Phonon Scattering ◽

Pulse Discharge ◽

Molar Ratios ◽

Performance Reduction ◽

Compound Matrix

ABSTRACTCobalt triantimonide compounds are well known as materials with good thermoelectric properties over temperature range of 550-900 K. For further improving thermoelectric performance, reduction of thermal conductivity is required. In this study, we attempted to disperse carbon nanotubes (CNTs) homogeneously into the n-type CoSb3 compound for lowering lattice thermal conductivity by the phonon scattering. Powders of Co, Ni, Sb and Te were blended with molar ratios of n-type Co0.92Ni0.08Sb2.96Te0.04 compound, and the compound was synthesized through a pulse discharge sintering (PDS) process. After coarsely grinding the synthesized compound, CNTs were mixed with the compound powder at different mass% (0, 0.01, 0.05 and 0.1 mass%). Then, the mixture was mechanically ground with a planetary ball milling equipment. The ground composite powder was compacted and sintered by PDS. Thermoelectric properties (Seebeck coefficient, electrical resistivity and thermal conductivity) of the sintered samples were measured. It was confirmed that the fibrous CNTs existed homogeneously in the compound matrix. The absolute value of Seebeck coefficient slightly decreased with increase of CNT content. The minimum thermal conductivity was obtained at addition of 0.01mass%CNT, and the electrical resistivity was a little increased with CNT content. The maximum ZT of 0.98 was achieved at 853 K in the 0.01mass%CNT-added sample.

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The effect of filler functionalization on dispersion and thermal conductivity of polypropylene/multi wall carbon nanotubes composites

Composites Part B Engineering ◽

10.1016/j.compositesb.2016.03.072 ◽

2016 ◽

Vol 94 ◽

pp. 350-359 ◽

Cited By ~ 34

Author(s):

Antonella Patti ◽

Pietro Russo ◽

Domenico Acierno ◽

Stefano Acierno

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Multi Wall Carbon Nanotubes

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Thermal Conductivity of Diamond Packed Electrospun PAN-Based Carbon Fibers Incorporated with Multi Wall Carbon Nanotubes

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.11992 ◽

2016 ◽

Vol 16 (2) ◽

pp. 1843-1847 ◽

Cited By ~ 4

Author(s):

Qi Dong ◽

Chunyuan Lu ◽

Kelimu Tulugan ◽

Chunzi Jin ◽

Soo Jong Yoon ◽

...

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Carbon Fibers ◽

Multi Wall Carbon Nanotubes

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Measurements of the Intrinsic Thermal Conductivity of Individual Multi-Wall Carbon Nanotubes

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44340 ◽

2011 ◽

Author(s):

Juekuan Yang ◽

Scott W. Waltermire ◽

Yang Yang ◽

Deyu Li ◽

Yunfei Chen

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Heat Source ◽

Thermal Resistance ◽

Effective Thermal Conductivity ◽

Experimental Studies ◽

Contact Thermal Resistance ◽

Multi Wall Carbon Nanotubes ◽

The Past ◽

Thermal Conductivities

Thermal transport through carbon nanotubes (CNTs) attracted a lot of attention over the past decade. Several experimental studies have been carried out to determine the thermal conductivities of CNTs [1–3]. However, the measurements are based on an individual CNT sample between two suspended membranes and the results actually include both the intrinsic thermal resistance of the CNT and the contact thermal resistance between the CNT and the two suspended membranes that serve as a heat source and a heat sink. Hence, the effective thermal conductivity extracted from these measurements should be lower than the intrinsic thermal conductivities of the CNTs measured. To minimize the contact thermal resistance, electron beam induce deposition (EBID) of different metals has been used to increase the contact area between the CNT and the heat source and sink [3,4]. However, it is still not clear how effective this treatment is and to what level the effective thermal conductivity obtained after the EBID treatment reflects the intrinsic one.

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Enhanced figure of merit in Mg2Si0.877Ge0.1Bi0.023/multi wall carbon nanotube nanocomposites

RSC Advances ◽

10.1039/c5ra12225b ◽

2015 ◽

Vol 5 (80) ◽

pp. 65328-65336 ◽

Cited By ~ 16

Author(s):

Nader Farahi ◽

Sagar Prabhudev ◽

Matthieu Bugnet ◽

Gianluigi A. Botton ◽

Jianbao Zhao ◽

...

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Carbon Nanotube ◽

Power Factor ◽

Figure Of Merit ◽

Phonon Scattering ◽

Thermoelectric Performance ◽

Multi Wall Carbon Nanotubes ◽

Energy Filtering ◽

Multi Wall Carbon Nanotube

Adding multi wall carbon nanotubes to Mg2Si0.877Ge0.1Bi0.023 led to an increased power factor via energy filtering as well as a lowered thermal conductivity via increased phonon scattering, and thus an enhanced thermoelectric performance.

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Thermal Conductivity and Electrical Resistivity of Melt-Mixed Polypropylene Composites Containing Mixtures of Carbon-Based Fillers

Polymers ◽

10.3390/polym11061073 ◽

2019 ◽

Vol 11 (6) ◽

pp. 1073 ◽

Cited By ~ 10

Author(s):

Beate Krause ◽

Piotr Rzeczkowski ◽

Petra Pötschke

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Electrical Resistivity ◽

Carbon Fibers ◽

Filler Content ◽

Synergistic Effects ◽

Volume Resistivity ◽

Graphite Nanoplatelets ◽

Polypropylene Composites ◽

Carbon Based

Melt-mixed composites based on polypropylene (PP) with various carbon-based fillers were investigated with regard to their thermal conductivity and electrical resistivity. The composites were filled with up to three fillers by selecting combinations of graphite nanoplatelets (GNP), carbon fibers (CF), carbon nanotubes (CNT), carbon black (CB), and graphite (G) at a constant filler content of 7.5 vol%. The thermal conductivity of PP (0.26 W/(m·K)) improved most using graphite nanoplatelets, whereas electrical resistivity was the lowest when using multiwalled CNT. Synergistic effects could be observed for different filler combinations. The PP composite, which contains a mixture of GNP, CNT, and highly structured CB, simultaneously had high thermal conductivity (0.5 W/(m·K)) and the lowest electrical volume resistivity (4 Ohm·cm).

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