The Role of Nonlinear Friction in the Dewetting of Thin Film Polymers

TL;DR

This paper investigates how nonlinear friction and residual stresses influence the dewetting dynamics of thin polymer films, explaining phenomena like rim width evolution and velocity decrease that previous models could not fully account for.

Contribution

It introduces a model incorporating nonlinear friction and residual stresses to explain previously unexplained dewetting behaviors in thin polymer films.

Findings

Rim width exhibits a maximum over time due to nonlinear effects.

Nonlinear friction explains the rapid decrease in dewetting velocity.

Residual stresses contribute to the observed dewetting dynamics.

Abstract

The study of the dewetting of very thin polymer films has recently revealed many unexpected features (e.g. unusual rim morphologies and front velocities) which have been the focus of several theoretical models. Surprisingly, the most striking feature of all, that is a decrease of the rim width with time, have not yet been explained. In the present letter, we show how the combined effects of a non-linear friction between the film and the substrate, and the presence of residual stresses within the film, result in the presence of a maximum in the time evolution of the rim width. In addition, we show how the introduction of a non-linear friction can also simply explain the rapid decrease of the dewetting velocity with time observed experimentally.