ABSTRACT
We have shown that the polymer relaxation time is dependent upon the solvent quality. In the case of a bad solvent (poor solvent close to 9 conditions), the polymer diffusion reaches equilibrium even in the quickest experimental runs. Under worse solvent conditions, however, (poor solvent far from 6 conditions), the polymer does not achieve this equilibrium, even for the slowest experimental runs (minutes). Pushing the surfaces together with a greater force squeezes out the solvent and thus further reduces the rate of diffusion. In the worse solvency conditions, the pull-off force increases as a logarithmic function of the contact time. This is suggestive of reptation based primitive path fluctuations as the dominant mechanism of interdiffusion.
