Rheological and electrical properties of polycarbonate/multi-walled carbon nanotube composites

Sung, Youngje; Han, Mi Sun; Song, Ki Heon; Jung, Jae Kap; Lee, Heon Sang; Kum, C.K.; Joo, Jinsoo; Kim, W.N.

doi:10.1016/j.polymer.2006.04.008

Cited by 157 publications

(94 citation statements)

References 17 publications

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“…Pötschke et al [13] have reported an electrical percolation threshold above 0.5 vol.% of multiwall carbon nanotubes (MWNT) for MWNT-filled PC composites with an electrical conductivity value of 10 -9 S/cm. Sung et al [14] have found a similar percolation threshold and electrical conductivity for MWNT-filled PC composites, concluding that the degree of aggregation and aspect ratio of the nanotubes crucially affected the structure of the conductive network. Kim and Macosko [6] have recently reported an electrical conductivity of 10 -9 S/m for PC composites containing approximately 1 vol.% of graphene prepared by means of conventional melt-compounding, while Yoonessi and Gaier [10] reported electrical conductivities that were two orders of magnitude higher (10 -7 S/m) for graphene-filled PC composites with 0.14 vol.% of graphene prepared by the emulsion method.…”

Section: Introductionmentioning

confidence: 86%

Enhanced electrical conductivity in graphene-filled polycarbonate nanocomposites by microcellular foaming with sc-CO₂

Gedler

Antunes

Velasco

2016

Journal of Adhesion Science and Technology

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Electrically conductive polycarbonate foams containing a low concentration of graphene nanoplatelets (0.5 wt.%) were produced with variable range of expansion ratio by applying a high pressure batch foaming process using sc-CO2. The structure of the foams was assessed by means of SEM, AFM and WAXS, and the electrical conductivity was measured in the foam growing direction. Results showed that electrical conductivity of PC composite foams remarkably increased when compared to that of non-foamed PC composite, with both the electrical conductivity and the main cell size of the foams being directly affected by the resultant expansion ratio of the foam. This interesting result could be explained by the development of an interconnected graphene nanoparticle network composed by increasingly well-dispersed and reoriented graphene nanoplatelets, which was developed into the solid fraction of the foam upon foaming by sudden depressurizing of the plasticized CO2-saturated polycarbonate preform. Some evidences of morphological changes in the graphene nanoplatelets after foaming were obtained by analysing variations in graphene's (002) diffraction plane, whose intensity decreased with foaming. A reduction of the average number of layers in the graphene nanoplatelets was also measured, both Revised manuscript -2-evidences indicating that improved dispersion of graphene nanoparticles existed in the PC composite foams. As a result, foams with a proper combination of low density and enhanced electrical conductivity could be produced, enabling them to be used in applications such as EMI shielding.

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Section: Introductionmentioning

confidence: 86%

Enhanced electrical conductivity in graphene-filled polycarbonate nanocomposites by microcellular foaming with sc-CO₂

Gedler

Antunes

Velasco

2016

Journal of Adhesion Science and Technology

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“…Several authors have specifically studied the properties of PC-MWCNT composites, focusing on the melt rheology (Pötschke et al 2002;Du et al 2004;Abdel-Goad and Pötschke 2005;Sung et al 2005;Alig et al 2008), the mechanical response (Eitan et al 2006;Fornes et al 2006;Satapathy et al 2007), and the electrical properties (Du et al 2004;Sung et al 2006;Alig et al 2008;Saphiannikova et al 2012). Some authors have employed a combination of characterisation methods, such as the simultaneous electrical and rheological measurements of Alig et al (2008) and Zeiler et al (2010).…”

Section: Introductionmentioning

confidence: 99%

Viscoelastic melt rheology and time–temperature superposition of polycarbonate–multi-walled carbon nanotube nanocomposites

2013

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This work investigates the linear and non-linear viscoelastic melt rheology of four grades of polycarbonate melt compounded with 3 wt% Nanocyl NC7000 multiwalled carbon nanotubes and of the matching matrix polymers. Amplitude sweeps reveal an earlier onset of nonlinearity and a strain overshoot in the nanocomposites. Mastercurves are constructed from isothermal frequency sweeps using vertical and horizontal shifting. Although all nanocomposites exhibit a second plateau at ∼10 5 Pa, the relaxation times estimated from the peak in loss tangent are not statistically different from those of pure melts estimated from cross-over frequencies: all relaxation timescales scale with molar mass in the same way, evidence that the relaxation of the polymer network is the dominant mechanism in both filled and unfilled materials. Non-linear rheology is also measured in large amplitude oscillatory shear. A comparison of the responses from frequency and amplitude sweep experiments reveals the importance of strain and temperature history on the response of such nanocomposites.

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“…Most of the rheological studies have concentrated on the typical linear viscoelastic response and on the non terminal character at low frequencies, which is attributed to the formation of a filler network (Kharchenko et al 2004;Meincke et al 2004;Abdel-Goad and Potschke 2005;Xinfeng et al 2005;Hu et al 2006;Moniruzzaman and Winey 2006;Sung et al 2006;W ue ta l .2007a). To our knowledge, this low frequency behavior was reported first by Potschke et al in 2002.…”

Section: Introductionmentioning

confidence: 99%

“…Since then, more attention has been paid to rheological properties of CNTs/polymer nanocomposites with focus on the percolation threshold as one of the most important factors affecting the material properties or as a characterization parameter of the dispersion quality. Such a percolated system was studied using polyamide-6/MWCNT nanocomposites (Meincke et al 2004), polycarbonate/MWCNT composites (Abdel-Goad and Potschke 2005), polycarbonate/ functionalized MWCNT nanocomposites (Sung et al 2006), and poly(ethylene terephthalate)/MWCNT (Hu et al 2006). Finally, a few investigations on the modeling of the rheological behavior of carbon nanotubes suspended in low molecular weight polymeric resins have been recently carried out (Rahatekar et al 2006;Fan and Advani 2007;Hong and Kim 2007;M ae ta l .…”

Section: Introductionmentioning

confidence: 99%

Rheological properties and percolation in suspensions of multiwalled carbon nanotubes in polycarbonate

et al. 2009

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Rheological properties and percolation in suspensions ofAbstract This paper is concerned with several issues related to the rheological behavior of polycarbonate/ multiwalled carbon nanotube nanocomposites. The composites were prepared by diluting a masterbatch of 15 wt.% nanotubes using melt-mixing method, and the dispersion was analyzed by SEM, TEM, and AFM techniques. To understand the percolated structure, the nanocomposites were characterized via a set of rheological, electrical, and thermal conductivity measurements. The rheological measurements revealed that the structure and properties were temperature dependent; the percolation threshold was significantly lower at higher temperature suggesting stronger nanotube interactions. The nanotube networks were also sensitive to the steady shear deformation particularly at high temperature. Following preshearing, the elastic modulus decreased markedly suggesting that the nanotubes became more rigid. These results were analyzed using simple models for suspensions of rod-like particles. Finally, the rheological, electrical, and thermal conductivity percolation thresholds were compared. As expected, the rheological threshold was smaller than the thermal and electrical threshold.

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Rheological and electrical properties of polycarbonate/multi-walled carbon nanotube composites

Cited by 157 publications

References 17 publications

Enhanced electrical conductivity in graphene-filled polycarbonate nanocomposites by microcellular foaming with sc-CO₂

Enhanced electrical conductivity in graphene-filled polycarbonate nanocomposites by microcellular foaming with sc-CO₂

Viscoelastic melt rheology and time–temperature superposition of polycarbonate–multi-walled carbon nanotube nanocomposites

Rheological properties and percolation in suspensions of multiwalled carbon nanotubes in polycarbonate

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Rheological and electrical properties of polycarbonate/multi-walled carbon nanotube composites

Cited by 157 publications

References 17 publications

Enhanced electrical conductivity in graphene-filled polycarbonate nanocomposites by microcellular foaming with sc-CO2

Enhanced electrical conductivity in graphene-filled polycarbonate nanocomposites by microcellular foaming with sc-CO2

Viscoelastic melt rheology and time–temperature superposition of polycarbonate–multi-walled carbon nanotube nanocomposites

Rheological properties and percolation in suspensions of multiwalled carbon nanotubes in polycarbonate

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Enhanced electrical conductivity in graphene-filled polycarbonate nanocomposites by microcellular foaming with sc-CO₂

Enhanced electrical conductivity in graphene-filled polycarbonate nanocomposites by microcellular foaming with sc-CO₂