24 Dielectric Properties and AC Conductivity of Epoxy/Hybrid Nanocarbon. . .
391
threshold in σ dc conductivity for these composites. It was found that the increase
of CNT in hybrid filler promotes the high increase of dielectric permittivity and
dissipation factor tanδ and, accordingly, shift of the maximum of permittivity and
dielectric loss into lower concentration of filler. It was concluded that the presence
of GNP in hybrid filler GNP/CNT expands the filler concentration range before
percolation and blocks the aggregation of CNTs that leads to increase of the number
of formed microcapacitors and enhances dielectric permittivity.
The mechanism of electrical conductivity in these CMs is electron tunneling
between neighboring fillers and/or clusters. The increase of CNT content in CMs
increases the electrical conductivity and weakens its dependence on frequency
(related to electron tunneling transport process in CMs) due to more effective formation of a continuous carbon network and turning of diffusive electron
transport.
References
1. Stankovich S, Dikin DA, Dommett GHB, Kohlhaas KM, Zimney EJ, Stach EA, Piner RD,
Nguyen ST, Ruoff RS (2006) Graphene composite materials. Nature 442:282–286
2. Lee CG, Wei XD, Kysar JW, Hone J (2008) Measurement of the elastic properties and intrinsic
strength of monolayer graphene. Science 321:385–388
3. Balandin AA, Ghosh S, Bao W, Calizo I, Teweldebrhan D, Miao F, Lau C-N (2008) Superior
thermal conductivity of single-layer graphene. Nano Lett 8(3):902–907
4. Wang Z, Luo J, Zhao G–L (2014) Dielectric and microwave attenuation properties of graphene
nanoplatelet–epoxy composites. AIP Adv 4:017139
5. Zhang H-B, Yan Q, Zheng W-G, He Z, Zhong-Zhen Y (2011) Tough graphene-polymer
microcellular foams for electromagnetic interference shielding. ACS Appl Mater Interfaces
3(3):918–924
6. Zhang HB, Zheng WG, Yan Q, Yang Y, Wang J, Lu ZH, Ji G-Y, Yu Z-Z (2010) Electrically conductive polyethylene terephthalate/graphene nanocomposites prepared by melt compounding.
Polymer 51:1191–1196
7. He L, Tjong SC (2013) Low percolation threshold of graphene/polymer composites prepared
by solvothermal reduction of graphene oxide in the polymer solution. Nanoscale Res Lett
8:132
8. Mansour SA, Al-ghoury ME, Shalaan E, El Eraki MHI, Abdel-Bary EM (2011) Dielectric
dispersion and AC conductivity of acrylonitrile butadiene rubber-poly(vinyl chloride)/graphite
composite. J Appl Polym Sci 122(2):1226–1235
9. Wang D, Bao Y, Zha J-W, Zhao J, Dang Z-M, Hu G-H (2012) Improved dielectric properties
of nanocomposites based on poly(vinylidene fluoride) and poly(vinyl alcohol)-functionalized
graphene. ACS Appl Mater Interfaces 4:6273–6279
10. Brosseau C, Beroual A (2001) Effective permittivity of composites with stratified particles. J
Phys D Appl Phys 34:704–710
11. Hashemi R, Weng GJ (2016) A theoretical treatment of graphene nanocomposites with
percolation threshold, tunneling-assisted conductivity and microcapacitor effect in AC and DC
electrical settings. Carbon 96:474–490
12. El Bouazzaoui S, Achour ME, Brosseau C (2011) Microwave effective permittivity of carbon
black filled polymers: comparison of mixing law and effective medium equation predictions. J
Appl Phys 110:074105
391
threshold in σ dc conductivity for these composites. It was found that the increase
of CNT in hybrid filler promotes the high increase of dielectric permittivity and
dissipation factor tanδ and, accordingly, shift of the maximum of permittivity and
dielectric loss into lower concentration of filler. It was concluded that the presence
of GNP in hybrid filler GNP/CNT expands the filler concentration range before
percolation and blocks the aggregation of CNTs that leads to increase of the number
of formed microcapacitors and enhances dielectric permittivity.
The mechanism of electrical conductivity in these CMs is electron tunneling
between neighboring fillers and/or clusters. The increase of CNT content in CMs
increases the electrical conductivity and weakens its dependence on frequency
(related to electron tunneling transport process in CMs) due to more effective formation of a continuous carbon network and turning of diffusive electron
transport.
References
1. Stankovich S, Dikin DA, Dommett GHB, Kohlhaas KM, Zimney EJ, Stach EA, Piner RD,
Nguyen ST, Ruoff RS (2006) Graphene composite materials. Nature 442:282–286
2. Lee CG, Wei XD, Kysar JW, Hone J (2008) Measurement of the elastic properties and intrinsic
strength of monolayer graphene. Science 321:385–388
3. Balandin AA, Ghosh S, Bao W, Calizo I, Teweldebrhan D, Miao F, Lau C-N (2008) Superior
thermal conductivity of single-layer graphene. Nano Lett 8(3):902–907
4. Wang Z, Luo J, Zhao G–L (2014) Dielectric and microwave attenuation properties of graphene
nanoplatelet–epoxy composites. AIP Adv 4:017139
5. Zhang H-B, Yan Q, Zheng W-G, He Z, Zhong-Zhen Y (2011) Tough graphene-polymer
microcellular foams for electromagnetic interference shielding. ACS Appl Mater Interfaces
3(3):918–924
6. Zhang HB, Zheng WG, Yan Q, Yang Y, Wang J, Lu ZH, Ji G-Y, Yu Z-Z (2010) Electrically conductive polyethylene terephthalate/graphene nanocomposites prepared by melt compounding.
Polymer 51:1191–1196
7. He L, Tjong SC (2013) Low percolation threshold of graphene/polymer composites prepared
by solvothermal reduction of graphene oxide in the polymer solution. Nanoscale Res Lett
8:132
8. Mansour SA, Al-ghoury ME, Shalaan E, El Eraki MHI, Abdel-Bary EM (2011) Dielectric
dispersion and AC conductivity of acrylonitrile butadiene rubber-poly(vinyl chloride)/graphite
composite. J Appl Polym Sci 122(2):1226–1235
9. Wang D, Bao Y, Zha J-W, Zhao J, Dang Z-M, Hu G-H (2012) Improved dielectric properties
of nanocomposites based on poly(vinylidene fluoride) and poly(vinyl alcohol)-functionalized
graphene. ACS Appl Mater Interfaces 4:6273–6279
10. Brosseau C, Beroual A (2001) Effective permittivity of composites with stratified particles. J
Phys D Appl Phys 34:704–710
11. Hashemi R, Weng GJ (2016) A theoretical treatment of graphene nanocomposites with
percolation threshold, tunneling-assisted conductivity and microcapacitor effect in AC and DC
electrical settings. Carbon 96:474–490
12. El Bouazzaoui S, Achour ME, Brosseau C (2011) Microwave effective permittivity of carbon
black filled polymers: comparison of mixing law and effective medium equation predictions. J
Appl Phys 110:074105