Colloidal gels: equilibrium and non-equilibrium routes

Colloidal gels: equilibrium and non-equilibrium routes

We attempt a classification of different colloidal gels based on colloidcolloid interactions. We discriminate primarily between non-equilibrium and equilibrium routes to gelation, the former case being slaved to thermodynamic phase separation while the latter is individuated in the framework of competing interactions and of patchy colloids. Emphasis is put on recent numerical simulations of col...

Experimental determination of order in non-equilibrium solids using colloidal gels

The idea of quantifying order in disordered systems has been introduced recently by Torquato and co-workers (2000 Phys. Rev. E 62 993–1001). We are interested in the application of this idea to measure structure in non-equilibrium systems. Here we focus on gels, using as a model system colloidal gels formed from hard spheres with polymer added to the systems to induce a controlled, weak attract...

Structure and Dynamics of Equilibrium and Non-Equilibrium Systems: Colloidal Suspensions in Confining Light Fields

Observation of empty liquids and equilibrium gels in a colloidal clay.

The relevance of anisotropic interactions in colloidal systems has recently emerged in the context of the rational design of new soft materials. Patchy colloids of different shapes, patterns and functionalities are considered the new building blocks of a bottom-up approach toward the realization of self-assembled bulk materials with predefined properties. The ability to tune the interaction ani...

Equilibrium concentration profiles and sedimentation kinetics of colloidal gels under gravitational stress.

We study the sedimentation of colloidal gels by using a combination of light scattering, polarimetry and video imaging. The asymptotic concentration profiles (z,t → ∞) 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 theoret...