Mixtures of anisotropic and spherical colloids: Phase behavior, confinement, percolation phenomena and kinetics

Purely entropic systems such as suspensions of hard rods, platelets and spheres show rich phase
behavior. Rods and platelets have successfully been used as models to predict the equilibrium
properties of liquid crystals for several decades. Over the past years hard particle models have
also been studied in the context of non-equilibrium statistical mechanics, in particular regarding
the glass transition, jamming, sedimentation and crystallization. Recently suspensions of hard
anisotropic particles also moved into the focus of materials scientists who work on conducting soft
matter composites. An insulating polymer resin that is mixed with conductive filler particles becomes
conductive when the filler percolates. In this context the mathematical topic of connectivity
percolation finds an application in modern nano-technology. In this article, we briefly review recent
work on the phase behavior, confinement effects, percolation transition and phase transition
kinetics in hard particle models. In the first part, we discuss the effects that particle anisotropy
and depletion have on the percolation transition. In the second part, we present results on the
kinetics of the liquid-to-crystal transition in suspensions of spheres and of ellipsoids.