Authors Pötschke, P. ; Abdel-Goad, M. ; Pegel, S. ; Jehnichen, D. ; Mark, J.E. ; Zhou, D. ; Heinrich, G.
Title Comparisons among electrical and rheological properties of melt-mixed composites containing various carbon nanostructures
Date 25.01.2010
Number 20583
Abstract The present investigation compares different carbon-based nanoscaled materials with regard to their effectiveness in producing thermoplastic polymers with antistatic and electrically conductive behavior. The dispersed phases are carbon black (CB) as spherical particles, multiwalled carbon nanotubes (MWNT) as fiber-like filler, and expanded graphite (EG) as platelet-like filler. Each was incorporated into polycarbonate by small-scale melt mixing. The electrical percolation concentrations were found to be 2 wt% for MWNT, 4 wt% for EG, and 8.75 wt% for CB which parallels the aspect ratios of the fillers. For EG a strong dependence of morphology and electrical resistivity on mixing time was observed, indicating a structural change/destruction during intensive shear mixing. Rheological percolation thresholds were found to be lower than electrical percolation threshold for the MWNT and CB, but similar in the case of EG. The general impact on complex melt viscosity decreases in the order MWNT, CB, EG. For EG, at higher loadings (above 4wt%) the viscosity increase with filler content is delayed as is the decrease in resistivity.
Publisher Journal of Macromolecular Science - A: Pure Applied Chemistry
Citation Journal of Macromolecular Science - A: Pure Applied Chemistry 47 (2010) 12-19

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