STICK AND SLIP BEHAVIOR OF CONFINED OLIGOMER MELTS UNDER SHEAR - A MOLECULAR-DYNAMICS STUDY

The flow behaviour of melts of short chains, confined in molecularly t hin Couette flow geometries, is studied with molecular-dynamics simula tions. The effect of wall attraction and confinement on the density an d velocity profiles is analysed. In these highly inhomogeneous films, a strong correlation between the density and velocity profile is found . Sticking of the interfacial layer on the wall and slip on the wall a nd inside the film is manifested by changes in the velocity profile. T he location of the slip is determined by the strength of the wall attr action.