Mathematical models for particle adsorbing polymer chains from polyelelctrolyte solution and the interaction between two particles adsorbing polymer were derived by adopting predecessor-determined random walk model (PDRWM) on the basis of self-consistent field and statistical thermodynamics. The interactions among particle

polymer segment and solvent molecule

as well as the effect of charged groups in polymer chains were taken into account in these models. The profile of segment density distribution was derived. The change of free energy of the interaction between two particles adsorbing polymer was also derived according to the change in particle surface free energy.