Regensburg 2007 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
SYPE: Symposium Polyelectrolytes
SYPE 2: Polyelectrolytes I
SYPE 2.6: Vortrag
Donnerstag, 29. März 2007, 15:30–15:45, H37
growth of polyelectrolyte complex nanoparticles: experimental and simulation studies — •Vitaliy Starchenko1, 2, Martin Müller1, and Nikolai Lebovka2 — 1Leibniz-Institut für Polymer Forschung, Dresden, Deutschland — 2Ovcharenko-Institute of Biocolloidal Chemistry, Kiev, Ukraine
Formation of polyelectrolyte complex (PEC) nanoparticles is of large fundamental interest and has application potential in e.g. biomedicine (drug/protein carrier) and water treatment (flocculation). Monodisperse particles were prepared by mixing cationic poly(diallyldimethylammonium chloride) (PDADMAC) and anionic poly(styrenesulfonate) (PSS) at nonstoichometric monomer charge ratios followed by consecutive centrifugation, which was characterized by dynamic light scattering (DLS). Using this concept small primary particles of low aggregation number have been suggested to merge to larger secondary particles by attractive dispersive forces, while the colloidal stability and the final particle size is determined by electrostatic repulsion in line with the DLVO theory. To check for the role of the Debye length, we report herein on ionic strength dependence of the particle size. In conformity with theoretical assumptions a model based on Smoluchowski theory, which includes a colloidal potential according to DLVO theory, was developed. This model can be used exclusively for simulation of the coagulation process of particles on the colloid level. Hence, additionally the influence of polyelectrolyte molecular weight on the particle size was studied to figure out the Debye length dependent contribution on the macromolecular conformation level.