title: Manipulating and quantifying temperature-triggered coalescence with microcentrifugation.
abstract: In this paper we describe a new approach to quantify the stability and coalescence kinetics of thermally switchable emulsions using an imaging-based microcentrifugation method. We first show that combining synchronized high-speed imaging with microfluidic centrifugation allows the direct measurement of the thermodynamic stability of emulsions, as expressed by the critical disjoining pressure. We apply this to a thermoresponsive emulsion, allowing us to measure the critical disjoining pressure as a function of temperature. The same method, combined with quantitative image analysis, also gives access to droplet-scale details of the coalescence process. We illustrate this by measuring temperature-dependent coalescence rates and by analysing the temperature-induced switching between two distinct microscopic mechanisms by which dense emulsions can destabilise to form a homogeneous oil phase.
authors.affiliation: Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands. joris.sprakel@wur.nl.
authors.forename: Huanhuan
authors.initials: H
authors.lastname: Feng
authors.forename: Dmitry
authors.initials: D
authors.lastname: Ershov
authors.forename: Thomas
authors.initials: T
authors.lastname: Krebs
authors.forename: Karin
authors.initials: K
authors.lastname: Schroen
authors.forename: Martien A Cohen
authors.initials: MA
authors.lastname: Stuart
authors.forename: Jasper
authors.initials: J
authors.lastname: van der Gucht
authors.forename: Joris
authors.initials: J
authors.lastname: Sprakel