Issue 10, 2016

Charging and aggregation of latex particles in aqueous solutions of ionic liquids: towards an extended Hofmeister series

Abstract

The effect of ionic liquid (IL) constituents and other monovalent salts on the stability of polystyrene latex particles was studied by electrophoresis and light scattering in dilute aqueous suspensions. The surface charge and the aggregation rate were both sensitive to the type of ion leading to different critical coagulation concentration (CCC) values. Systematic variation of the type of IL cation and anion allows us to place these ions within the Hofmeister series. We find that the dicyanoamide anion should be placed between iodide and thiocyanate, while all 1-alkyl-3-methylimidazolium cations can be positioned to the left of the tetramethylammonium and ammonium ions. The hydrophobicity of the 1-butyl-1-methylpyrrolidinium (BMPL+) ion is intermediate between 1-ethyl-3-methylimidazolium (EMIM+) and 1-butyl-3-methylimidazolium (BMIM+). With increasing alkyl chain length, the 1-alkyl-3-methylimidazolium cations adsorb on the latex particles very strongly, and 1-hexyl-3-methylimidazolium (HMIM+) and 1-octyl-3-methylimidazolium (OMIM+) lead to pronounced charge reversal and to an intermediate restabilization region.

Graphical abstract: Charging and aggregation of latex particles in aqueous solutions of ionic liquids: towards an extended Hofmeister series

Article information

Article type
Paper
Submitted
24 Nov 2015
Accepted
07 Feb 2016
First published
09 Feb 2016
This article is Open Access
Creative Commons BY license

Phys. Chem. Chem. Phys., 2016,18, 7511-7520

Author version available

Charging and aggregation of latex particles in aqueous solutions of ionic liquids: towards an extended Hofmeister series

T. Oncsik, A. Desert, G. Trefalt, M. Borkovec and I. Szilagyi, Phys. Chem. Chem. Phys., 2016, 18, 7511 DOI: 10.1039/C5CP07238G

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements