The effect of solid wall interaction on an amorphous polyethylene thin film, using a Monte Carlo simulation on a high coordination lattice

A Monte Carlo simulation on a high coordination lattice employing the RIS scheme for short-range interaction and a Lennard-Jones potential for long-range interaction was carried out on C-120 polyethylene thin film adsorbed at an impenetrable solid wall as well as freestanding films at 443 and 343 K, respectively. The interaction between the solid wall and polymer chains was given by a step-like function whose well depth is is an element of. Three is an element of values, -6.0, -2.0, and 0.0 kJ/mol, were tested in order to study the influence of the solid wall on the static and dynamic properties of the film. Significant density increase near the solid wall with the strongest interaction was observed, giving rise to the contraction of film thickness, which is in accordance with experimental observation. The presence of the solid wall reduces the interfacial width relative to the free-standing film and the extent of the reduction shows a tendency to grow with the strength of the interaction and lowering temperature. The population of chain end groups is significantly depressed near the attractive solid wall. The chain mobility as a whole in the normal direction toward the him surface is retarded near the free surface and the solid wall, while the bead mobility is dependent on the nature of interactions. (C) 1999 Elsevier Science Ltd. All rights reserved.