Complexation behavior between polyelectrolyte stars and charged colloids

• Antragsteller: Professor Dr. Matthias Ballauff; Professor Dr. Christos N. Likos
• Fachliche Zuordnung: Theoretische Physik der kondensierten Materie
• Förderung: Förderung von 2006 bis 2012
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 22053299

The present project deals with the complexation and phase behavior of mixtures consisting of hard, spherical colloidal particles and oppositely charged polyelectrolyte stars (PES). These PEstars result when / polyelectrolyte chains are grafted on a common center. Preliminary simulation results have shown that when a single PES approaches an oppositely charged colloid, a complexation transition of morphological nature takes place. The PES completely attaches itself on the surface of the colloid, assuming thereby a two-dimensional form of a curved starfish that sticks to the colloid surface. Addition of salt causes a gradual unsticking transition of the PES, in which the arms of the latter appear to detach themselves from the colloid surface in a quantized fashion. In the present project, a systematic investigation of the behavior of such mixtures will be undertaken, in which simulations will directly be compared to experimental data. Ways to manipulate the complexation morphologies as well as the phenomenon of overcharging will be looked upon. The macroscopic behavior of concentrated solutions of such systems will be investigated both by theory, employing effective interaction potentials, and by experiment, by carrying out scattering experiments with labeled particles.

• DFG-Verfahren: Sachbeihilfen