Enhancing the electrical conductivity of carbon black/graphite nanoplatelets: Poly(ethylene‐butyl acrylate) composites by melt extrusion

Abstract

The influence of processing parameters such as screw geometry, temperature profile, and screw speed on the electrical properties of hybrid composites consisting of graphite nanoplatelets and carbon black in ethyl butyl acrylate was studied. Two different screws were used to compound the hybrid composites at two different temperatures and two different screw speeds. A beneficial effect was noted with regard to the electrical properties when adding nanoplatelets to the filler system. The cause could be a synergistic effect due to the difference in particle shape of the two fillers. Lower percolation thresholds were obtained with the conventional screw due to less breakage of the graphite nanoplatelets compared to the barrier screw. No significant changes of the electrical properties were observed when changing the temperature profiles or the screw speeds. Furthermore, the melt viscosity of the compounds was not appreciably affected at the rather low filler contents used here.

Linear and Nonlinear Rheology Combined with Dielectric Spectroscopy of Hybrid Polymer Nanocomposites for Semiconductive Applications

“…The CB was characterized by a surface area of 70 /g and a density of 1.8 g/ , while the GnP had a thickness of 6–8 nm, a characteristic diameter of 5 m, a surface area of 120–150 /g and a density of 2.2 g/ (manufacturer data). The composition of the EBA-GnP-CB hybrid nanocomposites was optimized by Oxfall et al [ 2 ], and Arino et al [ 3 ] further improved the electrical properties of the nanocomposites by varying the processing conditions, such as screw geometry, temperature profile and screw speed. A Brabender, Brabender GmbH, Duisburg, Germany, 19/25D (barrel diameter of 19 mm and barrel length of ) single-screw extruder, equipped with a 1.5-mm radius circular die was used for sample preparation.…”

“…However, significant challenges remain to be overcome in the development of graphene-based consumer products. In this framework, of particular importance is understanding the flow field-matrix-filler interaction in polymer nanocomposites [ 2 , 3 ]. By the method of processing, the microstructure can be tailored to attain the desired material properties by de-agglomerating the particles, improving dispersion and ensuring the desired orientation of the nanofillers in the melt [ 4 ].…”

“…However, applications such as semi-conductive layers for high voltage cables require highly filled carbon black nanocomposites that can pose problems to the manufacturing of the cables [ 17 , 18 ]. Hybrid EBA-GnP-CB nanocomposites for semiconductive high voltage cable applications were considered by Arino et al [ 3 ] and took advantage of synergistic effects due to the particle shape of the two fillers. The electrical conductivity of the nanocomposites was optimized via melt extrusion with different processing histories with a strong influence on the electrical percolation behavior [ 3 ].…”

“…Hybrid EBA-GnP-CB nanocomposites for semiconductive high voltage cable applications were considered by Arino et al [ 3 ] and took advantage of synergistic effects due to the particle shape of the two fillers. The electrical conductivity of the nanocomposites was optimized via melt extrusion with different processing histories with a strong influence on the electrical percolation behavior [ 3 ].…”

“…In the present study, the influence of processing conditions on percolated ethylene butyl acrylate (EBA) nanocomposites containing graphite nanoplatelets (GnP) and GnP-carbon black (CB) was investigated from the rheological point of view. Thermogravimetric analysis, scanning electron microscopy, optical microscopy and image analysis, X-ray diffraction, mechanical properties and capillary viscometry (high shear rates) analysis of the samples used in the present study can be found in Arino et al [ 3 ], and the two studies should be interpreted complementarily. In this publication, dynamic frequency and strain sweeps, extensional and rheo-dielectric tests are presented.…”