Dynamic Propagation Depth in Substrate-Supported Polymer Films: A Molecular Dynamics Simulation

Abstract

The properties of substrate-supported polymer films are strongly related to the properties of the substrate. This work studies the dynamic propagation depth of the substrate effect in polymer films using molecular dynamics simulations. From the layer-resolved diffusion of polymer chains, the dynamic propagation depth of the substrate effect into nonadsorbed chains λdyn is estimated to be about 2.3R g (R g is the radius of gyration of polymers in the bulk) and 3.5R g for the weakly and strongly attractive substrates, respectively, much larger than the thickness of the adsorbed layer h ads ≈ 1.2R g. The dynamics of adsorbed and nonadsorbed polymers located below λdyn strongly depend on the substrate attraction strength. Our results reveal that the influence of substrate on the nonadsorbed polymer chains comes mainly from the tails of adsorbed chains and provides new insights into the molecular mechanism of the propagation of the substrate effect in polymer films.

Effect of Polymer Architecture on the Adsorption and Coating Stability on Heterogeneous Biomimetic Surfaces

“…They highlighted the critical role of molecular modeling in optimizing the adsorption processes in industrial applications. Molecular dynamics was also used by Zhou et al 25 to investigate how the strength of substrate attraction and polymer chain length affected the behavior of adsorbed and non-adsorbed chains in substrate-supported thin films. They found an influence zone beyond which the diffusion of polymer chains remained unaffected by the substrate.…”