This title appears in the Scientific Report :
2013
Please use the identifier:
http://dx.doi.org/10.1039/c3sm27754b in citations.
Please use the identifier: http://hdl.handle.net/2128/5038 in citations.
Structural arrest and texture dynamics in suspensions of charged colloidal rods
Structural arrest and texture dynamics in suspensions of charged colloidal rods
There is an abundance of experiments and theories on the glass transition of colloidal systems consisting of spherical particles. Much less is known about possible glass transitions in suspensions of rod-like colloids. In this study we present observations of a glass transition in suspensions of ver...
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Personal Name(s): | Kang, Kyongok (Corresponding author) |
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Dhont, Jan K.G. | |
Contributing Institute: |
Weiche Materie; ICS-3 |
Published in: | Soft matter, 9 (2013) 17, S. 4401-4411 |
Imprint: |
Cambridge
Royal Society of Chemistry (RSC)
2013
|
DOI: |
10.1039/c3sm27754b |
Document Type: |
Journal Article |
Research Program: |
Soft Matter Composites |
Link: |
OpenAccess Published under German "Allianz" Licensing conditions on 2013-02-26. Available in OpenAccess from 2014-02-26 |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/5038 in citations.
There is an abundance of experiments and theories on the glass transition of colloidal systems consisting of spherical particles. Much less is known about possible glass transitions in suspensions of rod-like colloids. In this study we present observations of a glass transition in suspensions of very long and thin rod-like, highly charged colloids. We use as a model system fd-virus particles(a DNA strand covered with coat proteins) at low ionic strength, where thick electric double layers are present. Structural arrest as a result of particle-caging is observed by means of dynamic light scattering. The glass-transition concentration is found to be far above the isotropic-nematic coexistence region. The morphology of the system thus consists of nematic domains with different orientations. Below the glass-transition concentration the initial morphology with large shear-aligned domains breaks up into smaller domains, and equilibrates after typically 50-100 hours. We quantify the dynamics of the transitional and the equilibrated texture by means of image time-correlation. A sharp increase of relaxation times of image time-correlation functions is found at the glass-transition concentration. The texture dynamics thus freezes at the same concentration where structural arrest occurs. We also observe a flow instability, which sets in after very long waiting times (typically 200-300 hours), depending on the rod concentration, which instability affects the texture morphology. |