A generalized Zimm model: Hydrodynamic screening in polymer solutions

This work presents a phenomenological theory for the single-chain dynamics in semidilute and concentrated polymer solutions and allows to describe the crossover from Zimm to Rouse-like behavior both in time domain and in spatial domain. The polymer solution is described as a set of oscillators fixed in space and submerged in an incompressible fluid. It is shown that the coupled equations of motion of such a polymer system give rise to the time dependence of the Oseen-like tensor and, as a consequence, the time-dependent hydrodynamic screening length. Monomer mean-square displacements and the single-chain dynamic structure factor are calculated.