Dynamics of ring polymer melts: Memory function approach
We investigated the static and dynamic properties of a Rouse ring polymer modified by introducing an effective, spherically symmetric, attractive potential of entropic nature and a memory function describing the effect of dynamic entanglement. Renormalized Rouse formalism is used to approximate the time dependence of the memory matrix. The results obtained are in good agreement with existing experimental data and the results of computer simulations of ring polymer ring with , , where N_e is the number of Kuhn segments in linear polymer melts between neighboring entanglements and , the number of Kuhn segments. For large molecular weights, a refined self-consistent approximation is proposed to describe the time dependence of the memory function. It is shown that this approximation allows us to describe an exponential decrease in the self-diffusion coefficient with molecular weight of the rings, i.e., the effect of dynamic localization.