Abstract: We demonstrate how we can tune the size, shape, surface functionality and properties of nanoparticles and use them as ideal model systems for fundamental investigations as well as for materials applications. In particular we describe ways to create functionalized core-shell particles with various degree of anisotropy and interesting magnetic properties. We show how we can use these particles in order to study the equilibrium and non-equilibrium phase behavior of colloidal suspensions with different interaction potentials and summarize our current understanding of the phenomenon of dynamical arrest, i.e. gel and glass formation. While different nanoparticles are vital for fundamental studies of various aspects of soft condensed matter, they also offer fascinating possibilities in materials science. We will demonstrate this with the example of nanocomposites made through an in situ polymerization reaction.

Abstract: We have systematically investigated the phase diagram of clay particles in water to understand the relation between the local and macroscopic properties and the structures of clay suspensions. We focused, in particular, on sodium Cloisite (CNa) particles at concentrations typically used in nanocomposites (concentrations from 1 to 4 wt %) and at an extended range of ionic strengths (10(-5) to 10(-2) M NaCl). The suspensions have been characterized using rheology and a combination of scattering techniques (neutrons, X-rays, and light). We demonstrate the existence of a liquid cluster phase at low clay and intermediate salt concentrations and provide new insight into the nature of the solid-like dispersions at low and high ionic strengths.