Simulating the long-time viscoelastic response of long polymers

Simulating the long time dynamics of even a simple model polymer with a realistic number of monomers is impractical. We therefore use a renormalization procedure to represent an original polymer with fewer monomers. By showing that the results become independent of the number of beads in the chain, we can infer the stress-stress correlation function for a long polymer in both the short and long time regimes. To do so we simulate a chain of at most 32 monomers. Our value for the polymer contribution to the viscosity in the long polymer limit is consistent with theory. However, it comes toward the lower end of the range of theoretical predictions.