Dipolar colloids in apolar media: direct microscopy of two-dimensional suspensions

Erez Janai, Avner Cohen, Alexander V Butenko, Andrew B Schofield, Moty Schultz, Eli Sloutskin

Research output: Contribution to journalArticlepeer-review

Abstract

Spherical colloids, in an absence of external fields, are commonly assumed to interact solely through rotationally-invariant potentials, u(r). While the presence of permanent dipoles in aqueous suspensions has been previously suggested by some experiments, the rotational degrees of freedom of spherical colloids are typically neglected. We prove, by direct experiments, the presence of permanent dipoles in commonly used spherical poly(methyl methacrylate) (PMMA) colloids, suspended in an apolar organic medium. We study, by a combination of direct confocal microscopy, computer simulations, and theory, the structure and other thermodynamical properties of organic suspensions of colloidal spheres, confined to a two-dimensional (2D) monolayer. Our studies reveal the effects of the dipolar interactions on the structure and the osmotic pressure of these fluids. These observations have far-reaching consequences for the fundamental colloidal science, opening new directions in self-assembly of complex colloidal clusters.
Original languageEnglish
Article number28578
Number of pages10
JournalScientific Reports
Volume6
Early online date27 Jun 2016
DOIs
Publication statusPublished - 27 Jun 2016

Fingerprint

Dive into the research topics of 'Dipolar colloids in apolar media: direct microscopy of two-dimensional suspensions'. Together they form a unique fingerprint.

Cite this