Electrical properties of poly(phenylene sulfide)/multiwalled carbon nanotube composites prepared by simple mixing and compression

Abstract

Poly(phenylene sulfide) (PPS)/multiwalled carbon nanotubes (MWNTs) conductive composites were prepared through the simple mixing of PPS granules with MWNT powder and subsequent compression. The electrical properties as a function of MWNT loading clearly showed a low percolation threshold of about 0.22 vol % and a high critical exponent value of 3.55 for composites prepared by this method. A comparison study with composites prepared via melt mixing was also carried out, where a random dispersion of MWNTs was achieved. There existed a striplike morphology of MWNTs in the PPS matrix and MWNTs were selectively located in strips caused by compression. The effects of temperature and pressure on the conductivity of the PPS/MWNT composites as prepared via simple mixing and compression are discussed. In addition, the conductivity also showed a dependence on the flow direction of the compression, with higher conductivity in the direction parallel to the flow direction than in the direction perpendicular to the flow direction. So the relationship of the processing and morphological properties was investigated in detail. The possible conductive mechanisms of conventional melt blending and preparation via sample mixing and compression are also discussed.

Estudo das propriedades elétricas e térmicas de compósitos nanoestruturados de poli(sulfeto de fenileno) reforçados com nanotubos de carbono

“…Além disso, foi observado que o valor de (t) encontrado neste estudo foi maior que o esperado, conforme apresentado na teoria da percolação descrita na Equação 2. Yang et al [33] e Jang et al [34] determinaram, respectivamente, valores de 3,6 e 3,3 para o expoente critico de compósitos nanoestruturados de PPS/MWCNT. Este comportamento pode ser explicado através do modelo de percolação de tunelamento [35] , onde as partículas condutoras estão dispersas de maneira não aleatória no sistema, ou ainda sob a forma de pequenos aglomerados na matriz polimérica.…”

Dispersing carbon nanotubes in phenolic resin using an aqueous solution

“…Similar results have been reported by the literature. [6][7][8][9][10][11] Individual CNTs are active in the UV-Vis region and exhibit characteristic bands. However, bundled CNTs are hardly active in the wavelength region between 200 and 800 nm most probably due to charge transfer via tunneling between the respective nanotubes.…”

“…Therefore, despite the extremely high strength of individual CNT shells, the weak shear interactions between adjacent shells and tubes lead to significant reductions in the effective strength of multi-walled carbon nanotubes. [8][9][10][11][12] This is responsible for the carbon nanotube bundles down to only a few GPa. [8][9][10][11][12] Nowadays, phenolic resins are indeed irreplaceable materials for selective high-technology applications, offering high reliability under severe conditions.…”

“…[8][9][10][11][12] This is responsible for the carbon nanotube bundles down to only a few GPa. [8][9][10][11][12] Nowadays, phenolic resins are indeed irreplaceable materials for selective high-technology applications, offering high reliability under severe conditions. Because of its excellent ablative properties, structural integrity, thermal stability and solvent resistance, phenolic resins are still widely used, especially in thermal insulation materials, molding compounds, coatings and composite materials.…”

“…However, due to the strong van der Waals forces of single CNTs, this reinforcement tends to form bundles within production process. For thermoset resin, several works have been done [7][8][9][10][11][12] in order to deagglomerate CNT bundles using organic and inorganic surfactants solvents. Botelho et al 2041 Vol.…”