Contact electrification and the work of adhesion

TL;DR

This paper develops a general theory linking contact electrification to the work of adhesion between solids, using surface charge correlations derived from Kelvin Force Microscopy, with a focus on silicon rubber (PDMS).

Contribution

It introduces a theoretical framework connecting surface charge correlations to adhesion work, validated with experimental KFM data on PDMS.

Findings

Surface charge correlations significantly influence adhesion work.

The theory explains variations in adhesion observed in experiments.

Quantitative estimates of electrification effects on adhesion are provided.

Abstract

We present a general theory for the contribution from contact electrification to the work necessary to separate two solid bodies. The theory depends on the surface charge density correlation function, which we deduce from Kelvin Force Microscopy (KFM) maps of the surface electrostatic potential. For silicon rubber (polydimethylsiloxane, PDMS) we discuss in detail the relative importance of the different contributions to the observed work of adhesion.