Lecture Gerald G. Fuller
|18 January 2005||FWN-Building 5114.0004, Nijenborgh 4, 9747 AG, Groningen|
|Speaker:||Dr. Gerald G. Fuller|
|Affiliation:||Chemical Engineering, Stanford University|
|Title:||Connect the drops: wetting, adhesion, and rheology of particle-stabilized emulsions|
|Date:||Tue Jan 18, 2005|
|Telephone:||+31 50 363 6440|
Colloidal particles are attracted to liquid-fluid interfaces and can be induced to create remarkable, long-range structures by adjusting interparticle forces. These include two-dimensional crystals, flocculated networks, and foam-like aggregates. These interfaces find application in the stabilization of foams and emulsions, and are also useful analogs to appreciate the dynamics, structure, and phase behavior of two-dimensional systems.
The presence of adsorbed colloidal particles will endow an interface with important mechanical properties, such as viscoelasticity, bending moduli, and spontaneous curvature. This lecture describes shearing transitions in two-dimensional crystals, and the rheology of two-dimensional suspensions. Furthermore, the coalescence behavior of colloid-laden interfaces is explored as a means of understanding the stabilization mechanisms that are possible with emulsions in the presence of particles. Complementary systems, representing oil-in-water and water-in-oil emulsions, exhibit contrasting drainage mechanisms as they serve to temporarily stabilize the approaching surfaces. It is demonstrated that selecting the proper the contact angle of the particles allows them to bridge liquid interfaces and effectively bind droplets against one another.
|Last modified:||22 October 2012 2.31 p.m.|