Doing synthesis on the surface on polymer colloids

COLL 361

Geeta Sharma and Matthias Ballauff. University of Bayreuth, Physikalische Chemie I, Universitaetsstrasse, Bayreuth, 95440, Germany
If long polyelectrolyte chains are attached densely to colloidal latex particles, a spherical polyelectrolyte brush results. These spherical polyelectrolytes are dispersed in water and carry a high charge. We demonstrate that these systems can be used to immobilize ions of heavy metal as e.g. gold as counterions. Reduction of these ions leads to metallic nano-particles. In this way the brush layer attached to the surface of the particles becomes a “nano-reactor” that may be used for chemical conversions of the metal ions. We show that the reduction of AuCl4- ions within these nano-reactors leads to well-defined and rather monodisperse gold nano-particles that are attached to the surface of the core. A stable dispersion of polymeric core particles with attached nano-particles results. All results reported here suggest that chemical reactions of ions immobilized in spherical polyelectrolyte brushes provides a new route to composite particles of inorganic and organic materials.