R. Brand, H. Pleiner: Macroscopic aspects of field induced particle matrix interactions in magnetorheological elastomers and liquid crystalline gels
Description
The goal of this research project is to analyze the macroscopic and rheological properties of two classes of magnetic materials for which field-controlled particle-matrix interactions play an important role. The obtained results will then be applied to specific questions. On the one hand we will investigate the transition from magneto-rheological fluids to magneto-rheological elastomers in external fields. On the other hand the phase transitions and the hydrodynamic properties of liquid crystalline magnetic gels and elastomers will be studied. In all systems that will be investigated the properties of a permanent network as well as the formation of transient networks will play an important role. It is the latter ones which can be easily influenced and controlled by magnetic fields. Macroscopically non-conserved strain fields and relative rotations between the different subsystems will come into play – in addition to macroscopic variables, which are characteristic for magnetic degrees of freedom and for orientational degrees of freedom. The macroscopic approach pursued here naturally complements experimental investigations as well as projects modeling mesoscopic and microscopic aspects. We mention that very recently the group of A. Sanchez-Ferrer (ETH Zuerich) has been successful in synthesizing nanocomposites of liquid crystalline elastomers and magnetic nanoparticles [1,2].
Project Manager
Prof. Dr. Helmut R. Brand, Universität Bayreuth
Prof. Dr. Harald Pleiner, MPI für Polymerforschung, Mainz
Staff
Tilen Potisk, Universität Bayreuth
Grant period
2013 -
Publications
[1] J.M. Haberl, A. Sanchez-Ferrer, A.M. Mihut, H. Dietsch, A.M. Hirt, und R. Mezzenga, Strain-induced macroscopic magnetic anisotropy from smectic liquid-crystalline elastomer-maghemite nanoparticle hybrid nanocomposites, Nanoscale, 5, 5539 (2013).
[2] J.M. Haberl, A. Sanchez-Ferrer, A.M. Mihut, H. Dietsch, A.M. Hirt, und R. Mezzenga, Liquid-crystalline elastomer-nanoparticle hybrids with reversible switch of magnetic memory, Adv. Mat. 25, 1787 (2013)
Contact
Prof. Dr. Helmut R. Brand
Theoretische Physik III
Universität Bayreuth
95440 Bayreuth