Furthermore, the stabilization of the interfacial structure was further examined by separating the short-range interaction forces from the long-range interaction forces. The long-range repulsive conservative force was observed near the solid surface, which acted over a long distance from the solid surface (about 2-3 nm) after settling for a longer time at room temperature or heating. The layered density distributions were suppressed by settling for a more extended time at room temperature or heating at 80 ℃. This finally disappeared by settling at room temperature for 142 h; however, it remained after the heating for 16 h, followed by settling at room temperature for 24 h. The temperature dependence and the activation energy of this relaxation process are close to that for bulk viscoelastic relaxation, suggesting that it is mainly rate-limited by the same mechanism as bulk viscoelastic relaxation. On the other hand, the increase of the decay length for the long-range repulsive force on the interface showed a steeper time-temperature dependence and a larger activation energy than the bulk viscoelastic relaxation, which implies they were ratelimited by the activation energy for substitution of the molecular segments interacting with the solid surface.