Influence of Relative Humidity on Interparticle Capillary Adhesion

A homemade instrument is designed to directly characterize the adhesion between two rigid polymeric microspheres in the presence of moist air. The tensile load is measured as a function of approach distance at designated relative humidity (RH). The measurement is consistent with our model from the first approximation. The model is further extended to include a rough surface. Capillary adhesion force is shown to be monotonically increasing with RH for smooth surfaces but becomes more pronounced at low RH for rough surfaces. Moisture has a profound influence on interparticle adhesion, which has significant impacts on a wide range of industrial applications.

Automated summary

A homemade instrument is used to characterize the adhesion between rigid polymeric microspheres in moist air. The study demonstrates that capillary adhesion force is affected by humidity, especially on rough surfaces. Moisture significantly impacts interparticle adhesion and industrial applications.