TY - JOUR
T1 - Linear viscoelastic behavior of aggregated colloidal dispersions
AU - Wolthers, W.
AU - van den Ende, D.
AU - Breedveld, V.
AU - Duits, M.H.G.
AU - Potanin, A.A.
AU - Wientjes, R.H.W.
AU - Mellema, J.
PY - 1997
Y1 - 1997
N2 - The viscoelastic behavior of a depletion-flocculated dispersion of colloidal spheres is investigated at different volume fractions of the spheres, using a controlled stress and a dynamic rheometer. Combining the results, we obtain the storage G′ and loss G′′ moduli over a frequency range of 0.02<ω<200rad/s. The measured G′ gradually increases with increasing frequency, while G′′ almost remains constant, indicating a broad spectrum of relaxation times. To describe and explain the observed behavior of the moduli as a function of frequency and volume fraction in terms of microscopic parameters, a microrheological model based on the fractal concept is proposed. Comparing experimental results with model calculations, we find a good agreement between the two, with physically plausible parameter values.
AB - The viscoelastic behavior of a depletion-flocculated dispersion of colloidal spheres is investigated at different volume fractions of the spheres, using a controlled stress and a dynamic rheometer. Combining the results, we obtain the storage G′ and loss G′′ moduli over a frequency range of 0.02<ω<200rad/s. The measured G′ gradually increases with increasing frequency, while G′′ almost remains constant, indicating a broad spectrum of relaxation times. To describe and explain the observed behavior of the moduli as a function of frequency and volume fraction in terms of microscopic parameters, a microrheological model based on the fractal concept is proposed. Comparing experimental results with model calculations, we find a good agreement between the two, with physically plausible parameter values.
U2 - 10.1103/PhysRevE.56.5726
DO - 10.1103/PhysRevE.56.5726
M3 - Article
SN - 1063-651X
VL - 56
SP - 5726
EP - 5733
JO - Physical review E: Statistical physics, plasmas, fluids, and related interdisciplinary topics
JF - Physical review E: Statistical physics, plasmas, fluids, and related interdisciplinary topics
ER -