| Rheology of High-Interface Systems
(a two-day course) |
|
|
October 7 and 8, 2006 (Saturday and Sunday) |
|
All classes will begin
at 8:30 AM at the Holiday Inn By the Bay
in Portland, Maine. |
The short courses are held in conjunction with the
78th
Annual Meeting of The Society of Rheology (October
8-12, 2006)
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Instructor Biosketches
Gerald G. Fuller is Professor of Chemical Engineering at
Stanford University. Since joining Stanford in 1980 he has conducted
research in the areas of optical rheometry and interfacial rheometry.
He has co-authored 190 papers including the book “Optical Rheometry”
published by Oxford University Press. He has served as the President
of the Society of Rheology and was awarded the Bingham Medal from
the Society in 1997. In 2005 he was elected to the National Academy
of Engineering.
Jan Vermant is Professor of Chemical Engineering at the K. U.
Leuven in Belgium. His research focuses on bulk and interfacial
rheology and relations to flow-induced structures in complex fluids
and interfaces, particularly for colloidal dispersions. He is a
recipient of a Dupont Young Faculty Award (2002-2004).
Andy Kraynik is a technical
staff member at Sandia National Laboratories in Albuquerque, New
Mexico. Since joining Sandia in 1976 he has been involved in
research on liquid and solid foams with emphasis on a
microrheological point of view. He is currently the President of the
Society of Rheology and received the Distinguished Service Award in
2001.
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This two-day short course is aimed at systems where the rheology
and structure are dominated by the presence of high degrees of fluid
interface. Common examples include foams, emulsions, and blends.
Further cases come from biology where the behavior of phospholipid
monolayers and bilayers control the mechanical response of lung
surfactants, cells, and vesicles.
Course Outline
| Saturday Morning (all instructors) |
| |
The syllabus begins with a presentation of capillarity
and wetting. The concepts of surface tension, wetting,
contact angles, and capillary forces are discussed. The
Young-Laplace equations are developed and the stresses
imposed by curved interfaces are predicted. Marangoni
stresses arising from surface tension gradients are
described. The molecular structure of surfactants,
amphiphilic polymers, and proteins are described and their
manner of attachment to fluid interfaces is explained. The
attachment of colloidal particles to interfaces is also
described. The phase behavior of complex fluid interfaces is
explored along with the techniques to measure them. These
include Langmuir troughs and Wilhelmy balances, Brewster
angle and fluorescence microscopies, pendant drop, and du
Nouy tensiometers.
|
| Saturday Afternoon (Kraynik) |
| |
Foams are complex fluids in which gas bubbles are
dispersed in a small amount of liquid. Applications include
foods and beverages, froth flotation, petroleum production,
fire fighting, and polymer foam processing. Foams exhibit a
wide range of rheological properties (shear modulus, yield
stress, non-Newtonian shear viscosity, slip at the wall, and
expansion viscosity) that strongly depend on their
microstructure (cell size and liquid fraction), which can
evolve by various mechanisms (foam expansion, diffusive
coarsening, and foam drainage). Techniques for
characterizing foam structure and measuring foam rheology
will be reviewed. Models of foam structure ranging in
complexity from the regular honeycomb in two dimensions to
random polydisperse foams in three dimensions will be
discussed. The connection between macroscopic foam
properties and cell-level structure and flow mechanisms will
be illustrated with many examples.
|
| Sunday Morning (Fuller) |
| |
The rheology of emulsions and blends depends on the
interfaces (composition, deformation and orientation) that
divide the dispersed and continuous liquid phases.
Morphological processes, such as deformation, different
types of break-up and coalescence will cause the interfacial
contributions to the rheological behavior to depend on the
flow conditions and history. The base case of immiscible
mixtures with Newtonian components will be reviewed first.
The evolution of the rheological properties in combination
with in-situ observations of the microstructure will be
compared to the predictions of continuum models. The effects
of a presence of interfacial agents and the role of their
interfacial rheology will subsequently be addressed. Both
systems compatibilized by surfactants and block-copolymers,
as well as particle stabilized systems (Pickering systems)
will be addressed. It will be discussed how the
morphological processes which control the rheological
properties are altered by the presence of interfacial
agents.
|
| Second Afternoon (Vermant) |
| |
In many applications, the interfaces themselves respond
nonlinearly to deformation and flow. The non-Newtonian
rheology of these two-dimensional systems is a consequence
of strong interactions and cooperative behavior of molecular
amphiphiles and particles residing at the interface. In
analogy to their bulk counterparts, two-dimensional polymer
melts, gels, liquid crystals, and suspensions can assemble
at fluid interfaces and strongly affect the stability and
bulk rheology of emulsions, foams, and blends. Interfacial
rheology plays an important role in controlling coalescence
and Oswalt ripening. The rheology of important classes of
complex fluid interfaces is discussed and measurement
techniques are discussed. These include interfacial shear
and dilatational rheometry and the use of flow-microscopies
to image nonlinear interfacial flow responses. |
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Short course registration includes a complete set of
course notes. Registration fees are in U.S. dollars. Payment can be
made online with MasterCard,
Visa, Discover, or American Express.
| Registration Fee for |
Through 9/8/06 |
After 9/8/06 |
| |
Member |
$500 |
$600 |
| |
Non-Member*
(includes
membership for 2007) |
$555 |
$655 |
| |
Student Member |
$300 |
$375 |
| |
Student Non-Member*
(includes student membership for 2007) |
$325 |
$400 |
*Non-members who are registering to
attend the 78th Annual Meeting may register for the short course at
the member rates.
Cancellations for the short course received in
writing (The Society of Rheology
78th Annual Meeting, c/o Albert Co, Department of Chemical
and Biological Engineering, University of Maine, Orono,
ME 04469-5737, USA) by September 8, 2006
will be refunded minus a $30 administrative charge. Cancellations
after September 8, 2006 will only be refunded if the course is
overbooked and the seat is refilled (again, subject to a $30.00
administrative charge). Each class is limited to 40 students.
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Questions can be directed to Professor Michael J.
Solomon, University of Michigan, current chair of the SOR
Education Committee, at
mjsolo@umich.edu. |
