  The evolution over time of the non-linear slip behavior of a
polydimethylsiloxane (PDMS) polymer melt on a weakly adsorbing surface made of
short non-entangled PDMS chains densely end-grafted to the surface of a fused
silica prism has been measured. The critical shear rate at which the melt
enters the nonlinear slip regime has been shown to increase with time. The
adsorption kinetics of the melt on the same surface has been determined
independently using ellipsometry. We show that the evolution of slip can be
explained by the slow adsorption of melt chains using the Brochard-de Gennes's
model.
