Gravitational compression of colloidal gels

European Physical Journal E

Volumn 28, Issue 2, 2009, Pages 159-164

  Lietor Santos J J ^a,b   Kim, C ^a,c   Lu, P J ^a   Fernandez Nieves A ^a,b   Weitz, D A ^a  

^a HARVARD UNIVERSITY   (United States)

^b GEORGIA INSTITUTE OF TECHNOLOGY   (United States)

^c KENT STATE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

COLLOIDAL GELS; COMPRESSION PROCESS; DEPLETION GELS; GRAVITATIONAL STRESS; NON-LINEAR; PORO-ELASTIC MODELS; TIME EVOLUTIONS; VISCOUS STRESS;

GELS; GRAVITATION; TITRATION;

GELATION;

EID: 60049085118     PISSN: 12928941     EISSN: 1292895X     Source Type: Journal    
DOI: 10.1140/epje/i2008-10390-7     Document Type: Article

References (20)

1. G. Foffi, C.D. Michèle, F. Sciortino, P. Tartaglia, Phys. Rev. Lett. 94, 078301 (2005).
2. N.A.M. Verhaegh, D. Asnaghi, H.N.W. Lerkkerkerker, M. Giglio, L. Cipelletti, Physica A 242, 104 (1997).
3. S. Asakura, F. Oosawa, J. Chem. Phys. 22, 1255 (1954).
4. S. Manley, J.M. Skotheim, L. Mahadevan, D.A. Weitz, Phys. Rev. Lett. 94, 218302 (2005).
5. C. Kim, Y. Liu, A. Kühnle, S. Hess, S. Viereck, T. Danner, L. Mahadevan, D.A. Weitz, Phys. Rev. Lett. 99, 028303 (2007).
6. L. Anti, J. Goodwin, R. Hill, S. Owens, S. Papworth, J.A. Waters, Colloid Surf. 17, 67 (1986).
7. P. Greenspan, E. Mayer, S. Fowler, J. Cell. Biol. 100, 965 (1985).
8. P.J. Lu, J.C. Conrad, H.M. Wyss, A.B. Schofield, D.A. Weitz, Phys. Rev. Lett. 96, 028306 (2006).
9. A. Yethiraj, A. Blaaderen, Nature (London) 421, 513 (2003).
10. M.F. Hsu, E.R. Dufresne, D.A. Weitz, Langmuir 21, 4881 (2005).
11. D.R. Lide, 79th CRC Handbook of Chemistry and Physics (CRC Press, Boca Raton, 1999).
12. J. Brandup, Polymer Handbook (Wiley, New York, 1998).
13. We have performed similar experiments with polystyrene particles in the presence of non-adsorbing polymer. In this case, the system does not cream but rather sediments along the gravitational direction; as a result there are no depletion interactions with the upper liquid-air interface. Consistent with this, we find no delay time.
14. R. Buscall, Colloid Surf. 5, 269 (1982).
15. The volume fraction for gelation is taken from [8], which contains the phase diagram for our experimental system.
16. The length scale of a pixel in one of our images is 10 μm. We thus expect that the structure of the colloidal suspension should not greatly affect the transmission through the sample. We also assume that contributions arising from the scattering from other parts of the cell are negligible compared to the transmission [17].
17. J.K.G. Dhont, An Introduction to the Dynamics of Colloids (Elsevier, Amsterdam, 1996).
18. H. Darcy, Les fontaines publiques de la ville de Dijon (Dalmont, Paris, 1856).
19. A.D. Dinsmore, V. Prasad, I. Wong, D.A. Weitz, Phys. Rev. Lett. 96, 185502 (2007).
20. In the initial compression stages, the gel does not change appreciably its volume fraction. As a result, the elastic stress gradient in equation (9) can be neglected. The initial stages are thus determined by the balance between the gravitational and frictional stress gradients. This is used to determine the initial permeability of the gel from the slope of the interface evolution with time. See [4] for further details.