Modelling of the rheological behaviour of CNT-polymer-composites

This aim of this project is to carry out fundamental studies on shear-induced structural changes in CNT-polymer-composites, in particular on reorganisation of the CNT-network under strong mechanical loads. The main objective is to develop such rheological material models that would describe the CNT-kinetics in polymer melts in the linear and nonlinear processing regimes. Further, it is planned to provide a coupling between a chosen rheological model and a percolation model for description of electrical conductivity in the CNT-polymer-composites (in cooperation with Deutschem Kunststoff-Institut Dramstadt). The future implementation of the coupled model into a flow simulation software should be patented together with industrial partners. The scientific results should be published and integrated into the current state of science and teaching.

Extensive experimental studies on rheological and dielectrical characterization of CNT-polymer-composites were carried out at the IPF in the frame of long-time close collaboration with the DKI. Recent theoretical research as well as common experimental studies represent a very good base for development of a coupled model and for successful implementation of the project. Furthermore, the IPF has a long experience on the experimental and theoretical studies of filler kinetics in elastomers and polymer melts by different mechanical loads. A number of thihotropic continuum models have been used to simulate the nonlinear viscoelastic behaviour of the filled polymer melts (see Figure).

BMBF "CarboNet"

The scheme of flow reversal experiment.
Flow reversal experiment with 5 wt% silicate nanocomposite: symbols – experiment; lines – Leonov theory. The shear stress is normalized on its stationary value. In collaboration with Mr. Francis Reny Costa.