Issue 30, 2013

Alternative dissipation mechanisms and the effect of the solvent in friction between polymer brushes on rough surfaces

Abstract

Surfaces covered with end-anchored polymers under good solvent conditions have excellent tribological properties. The friction between such surfaces is commonly attributed to steady-state interdigitation of the opposing polymer brushes. However, this conclusion tends to be based on idealized geometries neglecting surface roughness. Using molecular dynamics simulations, we find that there are qualitative differences between the friction of rough and flat polymer-brush surfaces. For rough surfaces the dissipation due to transient interdigitation and capillary- and shape-hysteresis is just as important or can even dominate over steady-state interdigitation. Having a mix of dissipation mechanisms that are all intertwined affects the observed friction force in linear-response as well as in the shear-thinning exponents and effective viscosity. Moreover, we find that the effect of the solvent viscosity is sublinear.

Graphical abstract: Alternative dissipation mechanisms and the effect of the solvent in friction between polymer brushes on rough surfaces

Supplementary files

Article information

Article type
Paper
Submitted
17 Feb 2013
Accepted
09 May 2013
First published
20 May 2013

Soft Matter, 2013,9, 7234-7241

Alternative dissipation mechanisms and the effect of the solvent in friction between polymer brushes on rough surfaces

S. de Beer and M. H. Müser, Soft Matter, 2013, 9, 7234 DOI: 10.1039/C3SM50491C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements