Confinement and compression of an oligomer brush

Abstract

Self-assembled monolayers and oligomer brushes confined between two parallel plates show compressional forces that are nonmonotonic as a function of plate separation. In a realistic model of short alkanethiols, based on the rotationally isomeric state model with parameters from ab initio calculations, the authors show that nonmonotonic forces arise from the elimination of longer conformers as the distance between the plates is reduced. This nonmonotonicity is a size effect that disappears when the length of the polymer molecule is sufficiently increased. An analytical model is developed that allows experimentalists to extract energy-averaged brush height distributions from compressional force curves.

Solvation force between tethered polyelectrolyte layers. A density functional approach

“…However, it has been also observed that polyelectrolytes may destabilize colloidal suspensions [42]. The problem of evaluation of the solvation forces between the surfaces modified with tethered charged chains and their dependence on the properties of a solvent and on the properties of the chains themselves was discussed in numerous papers [34,[43][44][45][46][47][48][49].…”