ISBN 9783843920162

978-3-8439-2016-2, Reihe Werkstoffwissenschaften

Johannes Krückel
Electrical and Rheological Behaviour of Carbon Black Filled Polymers

164 Seiten, Dissertation Universität Erlangen-Nürnberg (2014), Softcover, A5

Zusammenfassung / Abstract

The electrical properties of conductive polymer composites are determined by conductive particle structures which are the result of the interplay between shear and elongational flow components during the melt processing, as well as the filler and matrix properties. To study the influence of different flow deformations on the development of conductive particle structures in polymer melts, coupled electrical and rheological experiments provide a unique tool. On one hand, the electrical properties react very sensitively on changes of the conductive structures. On the other hand, such measurements allow the separation between shear and elongational flow components. Therefore it is possible to investigate the electrical properties of conductive polymer composites under defined deformations in the molten state. Moreover, it is possible to study the impact of the conductive fillers on the rheological properties of the composites. In this work composites, based on polymethylmethacrylate and a special conductive grade of carbon black, are investigated. The electrical conductivity of the composites prior, during, and after shear in oscillatory or constant stress mode is determined by direct current measurements. Moreover, simple physical models based on the experimental results are presented to obtain a deeper insight into the development of conductive particle structures.