Seminarium Zak³adu Mechaniki i Fizyki P³ynów

Hydrodynamics and Structure of Dispersion Colloids

prof. Gerhard Naegele (AMAS visiting professor, Institut für Festkörperforschung Jülich)

¶roda, 26 marca 2003

Dispersion colloids consist of submicron-sized solid particles dispersed in a low-molecular solvent. Typical examples of dispersion colloids are aqueous solutions of proteins or viruses (bio-polymers), and dispersions of synthetic latex particles. The Brownian stochastic dynamics of the colloidal particles is determined not only by direct inter-particle interactions like electrostatic and van der Waals forces. It depends also crucially on indirect hydrodynamic interactions (HI), mediated by the intervening solvent flow. Using analytic theory and computer simulations of model dispersions of charged, neutral and magnetic particles, we show that HI give rise to interesting and, quite often, surprising effects on various diffusional and viscoelastic properties.