Béziel W, Fragneto G, Cousin F, Sferrazza M
Département de Physique, Faculté des Sciences, Université Libre de Bruxelles, Boulevard du Triomphe, CP223, 1040 Bruxelles, Belgique.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Aug;78(2 Pt 1):022801. doi: 10.1103/PhysRevE.78.022801. Epub 2008 Aug 6.
We have investigated how the interface width between two thin polymer films approaches its equilibrium state. Neutron reflection for different polyolefin bilayers of various degrees of incompatibility as a function of the annealing time was measured. By tuning the interaction parameter, we have probed both an immiscible polymer couple and systems approaching criticality where the interface is wider. Since polymer chains have slow dynamics, we have observed the slow broadening of the interface connected to the growth at long times of the wavelength capillary-wave modes, which involve large-scale hydrodynamic flows.