Computer Simulation of Complexes of Dendrimers with Linear Polyelectrolytes

Abstract

Brownian dynamics computer simulations have been carried out of complexes formed by charged dendrimers and oppositely charged linear polymer chains of different degree of polymerization N ch . Bead−rod freely jointed models in the Debye−Hückel approximation without hydrodynamic interactions have been considered. Mean-square radii of gyration together with the radial density distribution functions have been calculated separately for a complex, a dendrimer, and a linear chain in a complex. The mean-square radius of gyration, the different monomer radial distribution functions, and the static structure factor for a dendrimer in a complex with long enough chains are very close to those for a single neutral dendrimer. The monomers of the linear chains with N ch equal to the number of the dendrimer's terminal charged groups are located very close to these terminal groups. For longer chains the total number of the chain monomers adsorbed onto a dendrimer exceeds the number that is necessary for a dendrimer neutralization, and the overcharging phenomenon is observed. Comparison with predictions of the correlation theory has been carried out.