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Extraordinary Flow Characteristics of Nanotube-Filled Polymer Materials



S B. Kharchenko, Kalman D. Migler, Jack F. Douglas, Jan Obrzut, E A. Grulke


Carbon nanotubes are under intense investigation due their potential for modifying the electrical conductivity (s), shear viscosity (h) and other transport properties of polymeric materials. They are hybrids of ordinary filler particles and nanoscale additives since their lengths are macroscopic (mm) while their cross-sectional dimensions are closer to molecular scales (nm). The combination of particle geometry, rigidity and deformability under flow allows nanotube additives to be mechanically dispersed in polymer matrices in the form of disordered network structures. Our measurements on these jammed indicate extraordinary property changes under flow. Specifically, s and h both decrease strongly with increasing shear rate in our (in situ) measurements on MWNT-polypropylene composites and these materials exhibit impressively large and negative normal stress differences.We illustrate the practical implications of these non-linear transport properties by showing that these additives can completely eliminate die swell in the pipe extrusion of the composite
Nature Materials


electrical conductivity, multiwall carbon nanotubes, normal stress, processing, rheology


Kharchenko, S. , Migler, K. , Douglas, J. , Obrzut, J. and Grulke, E. (2004), Extraordinary Flow Characteristics of Nanotube-Filled Polymer Materials, Nature Materials, [online], (Accessed March 1, 2024)
Created August 2, 2004, Updated February 17, 2017