Abstract
Course-grained Monte Carlo Brownian Dynamics simulations are used to simulate the nature of polyelectrolyte brushes. For the basic understanding, the effect of salt and surface charge density to the structure 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 of the polyion is set to 1.0 and 2.0 in order to discuss the Manning's counterion condensation. Thermal equilibrium structure in room temperature of a brush system without salt and a system of added 1:1 salt are compared. The effect of salt caused the decrease of film thickness as have been detected in small angle neutron scattering experiments. The difference of the thickness at the salt-free system is discussed with the polarization of counterion atmosphere.
