Configurational relaxation and diffusion of a flexible polymer in a dynamically disordered medium

Abstract

A stochastic model of the dynamics of a flexible linear polymer is developed and analyzed. The medium in which the polymer moves relaxes on a time scale whose value is an adjustable parameter, and may therefore be taken to be either long or short compared to the time scales of polymer motions. The polymer is represented by a freely jointed chain, which moves by a ‘‘kink–jump’’ algorithm. At any instant in time, a fraction of the chain’s beads are immobilized by obstacles that relax on an arbitrary time scale. The connection of this model to random walks with dynamical bond disorder is established, and calculations of the correlation function of the end‐to‐end vector and of the mean squared displacement of one bead are performed using the dynamical effective medium approximation.