Transcript Interfacial Structure of Pickering Emulsions Kjersta Larson-Smith and Prof. Danilo Pozzo University of Washington Chemical Engineering, Seattle WA • • • • • Particle stabilized emulsions (Pickering) form.

Interfacial Structure of Pickering Emulsions
Kjersta Larson-Smith and Prof. Danilo Pozzo
University of Washington Chemical Engineering, Seattle WA
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Particle stabilized emulsions (Pickering) form during the processing of organic fluids in the presence of
water and solid micro and/or nanoparticles.
Particles are enriched at the oil-water interface due to a favorable energy of adsorption.
Emulsion stability is controlled primarily by the structure of solid particles at the interface.
Nanoparticles and microparticles differ in their emulsion stabilization mechanisms: Steric vs. electrostatic
Project Accomplishments:
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Develop a scattering-based toolbox to probe the interfacial organization of the particles in the emulsion.
Probe interfacial transitions that occur in Pickering emulsions that are subjected to changing environmental conditions
(freeze-thaw cycles, pH and ionic strength).
Small Angle Neutron and X-ray Scattering
50 mm
Oil
Water
Model Emulsions: Hexadecane-inwater emulsions stabilized by
functionalized gold, polystyrene or
silica nanoparticles (4-100 nm)
Side-Project: A one-pot synthesis scheme
was developed to create amphiphilic
nanoparticles that strongly adsorb at
interfaces and also self-associate to form
stable cluster structures analogous to
micelles. Emulsions stabilized by
amphiphilic particles are now being
explored.
K. Larson-Smith, A. Jackson and D.C. Pozzo, J. Colloid and Interface Science, 343: 36 (2010)