Abstract
Monte Carlo Brownian Dynamics simulations are used to simulate the properties of polyelectrolyte brushes. For the basic understanding, the effect of linear charge density and surface density of polyelectrolyte brushes is studied. Polyions are grafted to the surface of up to several tens of nanometers pitch. For flexible polyion model of 128 segments, bond and bond angle degree of freedom is adopted. Linear charge density parameter ξ of the polyion is set to 0.5 to 4.0 in order to discuss the Oosawa-Manning's counterion condensation. Thermal equilibrium structure in room temperature of a brush system. When ξ is high, counterions are absorbed in the polyion layer. When the surface density decreases, the height of the brushes slightly increased in high ξ which is not consistent with the scaling theories, but could be understood by Oosawa theory. Net charge distribution showed a potential barrier when ξ is high, which may be related to the electric and kinetic dynamics of the surface.
