Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2007-10-29
Phys. Rev. E 78, 061402 (2008).
Physics
Condensed Matter
Soft Condensed Matter
11pages, 13 figures. submitted to Phys. rev. E
Scientific paper
10.1103/PhysRevE.78.061402
We report measurements of the frequency-dependent shear moduli of aging colloidal systems that evolve from a purely low-viscosity liquid to a predominantly elastic glass or gel. Using microrheology, we measure the local complex shear modulus $G^{*}(\omega)$ over a very wide range of frequencies (1 Hz- 100 kHz). The combined use of one- and two-particle microrheology allows us to differentiate between colloidal glasses and gels - the glass is homogenous, whereas the colloidal gel shows a considerable degree of heterogeneity on length scales larger than 0.5 micrometer. Despite this characteristic difference, both systems exhibit similar rheological behavior which evolve in time with aging, showing a crossover from a single power-law frequency dependence of the viscoelastic modulus to a sum of two power laws. The crossover occurs at a time $t_{0}$, which defines a mechanical transition point. We found that the data acquired during the aging of different samples can be collapsed onto a single master curve by scaling the aging time with $t_{0}$. This raises questions about the prior interpretation of two power laws in terms of a superposition of an elastic network embedded in a viscoelastic background. Keywords: Aging, colloidal glass, passive microrheology
Atakhorram M.
Bonn Daniel
Eiser Erika
Jabbari-Farouji Sara
MacKintosh Fred C.
No associations
LandOfFree
High-bandwidth viscoelastic properties of aging colloidal glasses and gels does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with High-bandwidth viscoelastic properties of aging colloidal glasses and gels, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High-bandwidth viscoelastic properties of aging colloidal glasses and gels will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-19465