Berlin 2012 – wissenschaftliches Programm

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 37: Poster: Rheology (joint focus with DRG)

CPP 37.7: Poster

Donnerstag, 29. März 2012, 18:45–19:45, Poster A

dynamics of thermosensitive core-shell dumbbell-shaped microgels — •Fangfang Chu, Miriam Siebenbürger, Nils Heptner, Joachim Dzubiella, Yan Lu, and Matthias Ballauff — Soft Matter and Functional Materials, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin, Germany

We present a study of the dynamics of dumbbell-shaped microgels. The thermosensitive dumbbell-shaped microgel latices consist of a dumbbell-shaped polystyrene-core and a themosensitive shell of cross-linked poly(N-isopropylacrylamide). These colloidal particles could be synthesized with an uniform size and morphology. The aspect ratio L*, which is defined as the ratio of the center to center distance L and the diameter D, was L*~0.24. Oscillatory experiments in the linear viscoelastic regime and flow curves in the steady sheared state were performed to investigate the phase diagram and the dynamics of concentrated dumbbell suspensions at various volume fractions and aspect ratios. The formation of a plastic crystal phase for higher volume fractions was found which was predicted by simulations [1,2,3]. For the higher volume fractions a glassy like behavior is found.

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