%0 Conference Proceedings
%T Equilibrium concentration profiles and sedimentation kinetics of colloidal gels under gravitational stress
%+ Dipartimento di Chimica
%+ Laboratoire Charles Coulomb (L2C)
%A Buzzaccaro, Stefano
%A Secchi, Eleonora
%A Brambilla, Giovanni
%A Piazza, R.
%A Cipelletti, Luca
%Z CNES, PRIN2008
%Z This is an author-created, un-copyedited version of an article accepted for publication in Journal of Physics Condensed Matter. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The definitive publisher-authenticated version will be available online
%< avec comité de lecture
%@ 0953-8984
%J Journal of Physics: Condensed Matter
%( NA
%B Eight Liquid Matter Conference
%C Vienna, Austria
%I IOP Publishing
%V 24
%N 28
%P 284103
%8 2011-09-06
%D 2011
%Z 1202.6474
%R 10.1088/0953-8984/24/28/284103
%K gels
%K colloids
%K settling
%K sedimentation
%K ligth scattering
%Z 47.57.ef,64.70.pv,82.70.Dd
%Z Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]Conference papers
%X We study the sedimentation of colloidal gels by using a combination of light scattering, polarimetry and video imaging. The asymptotic concentration profiles $\varphi(z,t\rightarrow \infty)$ exhibit remarkable scaling properties: profiles for gels prepared at different initial volume fractions and particle interactions can be superimposed onto a single master curve by using suitable reduced variables. We show theoretically that this behavior stems from a power law dependence of the compressive elastic modulus \textit{vs} $\varphi$, which we directly test experimentally. The sedimentation kinetics comprises an initial latency stage, followed by a rapid collapse where the gel height $h$ decreases at constant velocity, and a final compaction stage characterized by a stretched exponential relaxation of $h$ towards a plateau. Analogies and differences with previous works are briefly discussed.
%G English
%2 https://hal.science/hal-00675086/document
%2 https://hal.science/hal-00675086/file/GelLong_v2.pdf
%L hal-00675086
%U https://hal.science/hal-00675086
%~ CNRS
%~ L2C
%~ MIPS
%~ UNIV-MONTPELLIER
%~ GDR_MFA
%~ UM-2015-2021