Relaxation dynamics of langmuir polymer films: a power-law analysis.

We report an experimental study on the mechanical relaxation of Langmuir films of a flexible polymer: polyvinylacetate, a good example of a two-dimensional polymeric system at good-solvent conditions. This study allows us to explore the dependence of the relaxation times and the surface viscosity on the concentration. In the semidilute regime, both dynamical properties follow well-defined power laws, which are in quantitative agreement with 2D reptation.