Effect of chain flexibility on the dynamics of rodlikk polymers in the entangled state

The Brownian motion of semiflexible polymers in networks and in concentrated solutions is discussed. If the polymer is assumed to move only along itself by reptation, various time correlation functions are calculated rigorously. The results show that the Brownian motion is independent of the mesh size a over a wide range. It is then argued that the observed rodlike behavior of semiflexible polymers in concentrated solutions is due to the rapid bending fluctuation of the polymer.