Polymer diffusion in a lattice polymer model with an intrinsic reptation mechanism

Abstract

Rubinstein's repton model, extended by van Heukelum and Barkema for the simulation of polymer melts, is studied. This model has two dynamical mechanisms, explicit reptation and sideways motion, each with a prescribed rate. We study how the polymer diffusion coefficient depends on the ratio γ of these rates, while the sum of these rates is kept constant. We find that the diffusion coefficient of the polymers as a function of γ is not simply a linear combination of the contributions of the individual mechanisms; there is a large amount of cooperativity between the two kinds of mechanisms. A better understanding of this cooperativity might benefit research in a wide range of topics.