Relaxation of a single polymer chain trapped in an array of obstacles in two dimensions

Relaxation of a single polymer chain trapped in a periodic array of obstacl es in two dimensions is studied by Monte Carlo simulations of the bond fluc tuation model, where only tile excluded volume interaction is taken into ac count. Relaxation modes and rates of tile polymer chain are estimated by so lving a generalized eigenvalue problem for the equilibrium time correlation matrices of the coarse-grained relative positions of segments of the polym er chain. The Slowest relaxation rate lambda (1) of the polymer chain of N segments behaves as lambda (1) proportional to N-3.1. The pth,lowest relaxa tion rate lambda (p) with p greater than or equal to 2 shows the p-dependen ce lambda (p) proportional to p(2.1) and the N-dependence consistent with l ambda (p) proportional to N-3.1 for small values of p/N. For each N, the sl owest relaxation rate lambda (1) is remarkably smaller than the value extra polated from the behavior lambda (p) proportional to p(2.1) for p greater t han or equal to 2. The behaviors of slow relaxation modes are similar to th ose of the Rouse modes. These behaviors of tile relaxation rates and modes correspond to those of the slithering snake model with the excluded volume interaction.