Authors Liebscher, M. ; Gärtner, T. ; Tzounis, L. ; Micusik, M. ; Pötschke, P. ; Stamm, M. ; Heinrich, G. ; Voit, B.
Title Influence of the MWCNT surface functionalization on the thermoelectric properties of melt-mixed polycarbonate composites
Date 15.08.2014
Number 43042
Abstract The thermoelectric properties of conductive polymer composites consisting of a polycarbonate (PC) matrix loaded with different kinds of commercially available multi-walled carbon nanotubes (MWCNTs) have been examined. The PC/MWCNT composites were prepared by melt-mixing using a small-scale compounder. Unfunctionalized, as well as carboxyl (–COOH) and hydroxyl (–OH) modified MWCNTs were incorporated into the PC matrix at a constant amount of 2.5 wt.%, which is a concentration above the electrical percolation threshold. The amount of MWCNTs was kept low to understand the fundamental aspects of the physical properties and their correlation to the composite morphology. The results suggest that different functional groups on the surface of MWCNTs can have an impact on the thermoelectric values and the conductivity of the composites, measured at room temperature. The highest Seebeck coefficient (S) was found for the composite containing carboxyl functionalized MWCNTs (11.3 µV/K). In specific, an increase of the Seebeck coefficient was found with an increased oxygen content of MWCNTs. It is believed that these thermoelectric figure of merit values are still too low for commercial applications; however, they can be enhanced by increasing the amount of conducting fillers and improvement of dispersion in the polymer matrix.
Publisher Composites Science and Technology
Citation Composites Science and Technology 101 (2014) 133-138
Tags carbon nanotubes nano composites electrical properties thermal properties thermoelectric properties walled carbon nanotubes power-factor nanocomposites behavior dispersion efficiency networks films

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