Buckling of particle-laden interfaces

Theo D Kassuga; Jonathan P Rothstein

doi:10.1016/j.jcis.2015.02.012

Buckling of particle-laden interfaces

J Colloid Interface Sci. 2015 Jun 15:448:287-96. doi: 10.1016/j.jcis.2015.02.012. Epub 2015 Feb 11.

Authors

Theo D Kassuga¹, Jonathan P Rothstein²

Affiliations

¹ University of Massachusetts Amherst, Mechanical and Industrial Engineering Department, United States.
² University of Massachusetts Amherst, Mechanical and Industrial Engineering Department, United States. Electronic address: rothstein@ecs.umass.edu.

PMID: 25746181
DOI: 10.1016/j.jcis.2015.02.012

Abstract

In this paper, we investigate the buckling of an oil-water interface populated by micron-sized latex particles using a Langmuir trough. In this work, we extend results of buckling of particle-laden interfaces from the millimeter down to the submicron range while investigating the effect of a different capillary length on the resulting wavelength. The experimental data is compared to the existing theoretical framework. An unexpected deviation from the prediction of theory of the dominant wavelength of buckling is observed for particles smaller than one micron. Those observations suggest that there is a transition to a new buckling regime involving the formation of trilayers below one micron. For the first time in particle rafts, cascading of the dominant wavelength similar to that observed in thin polymer films is reported. In addition a series of transitions between wavelengths not observed in thin films is observed within the same particle raft. Lastly, the effect of compression history on the macroscopic arrangement of particles is investigated, along with its effect on the buckling wavelength.

Keywords: Cascading; Hysteresis; Particle-laden interfaces; Wavelength of buckling.