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東京大学理学系研究科・佐野研究室の上道雅仁です。
東大理・本郷での談話会の案内をさせていただきます。
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Date： Nov. 27, Monday, 15:30-16:30
Place： Faculty of Science Building #1, room 414 (4th Floor)
東京大学本郷キャンパス理学部1号館4階 414号室
Speaker： Dr. Andreas M. Menzel （Heinrich Heine University Dusseldorf）
Title： Mesoscopic modeling of magnetic elastomers and gels with links to
the macroscale
Abstract:
By the terms "magnetic gels" and "magnetic elastomers" we refer to
substances that consist of magnetic or magnetizable colloidal particles
embedded in an elastic polymer matrix, potentially swollen by a solvent.
Interesting behavior results for these materials as their overall
mechanical properties can be reversibly tuned from outside by external
magnetic fields. We study such situations by a mesoscopic approach that
discretizes the colloidal particles but treats the elastic matrix either
by simplified elastic interactions or by continuum elasticity theory. As
a result, we find a pronounced nonlinear stress-strain behavior for an
anisotropic class of the materials, switchable by external magnetic
fields. Similarly, we investigate the adjustability of the overall
static and dynamic elastic moduli by changes in the magnetic
interactions, depending on the spatial arrangement of the colloidal
particles. Apart from that, we developed a theoretical approach that
describes the coupled displacements and rotations of rigid particles in
a soft elastic gel matrix when they mutually repel or attract each other
as tuned by external magnetic fields. Comparison with experiments shows
good agreement and allows for micromechanical measurements of local
elastic moduli in elastic media.
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上道 雅仁
Masahito UWAMICHI
Higuchi Laboratory, Sano Laboratory
Graduate School of Science, The University of Tokyo
7-3-1 Hongo, Bunkyo-ku, Tokyo
113-0033 JAPAN
Email:uwamichi@daisy.phys.s.u-tokyo.ac.jp