The Interfacial and Colloid Science Group at the University of Washington
Dept. of Chemical Engineering is headed by Prof.
John C. Berg.
The Group presently has 5 graduate students, 1 post-doctorate and 3 undergraduate researchers.
Meet them below!
Interfacial and colloid science deals with the behavior of fine-particle
dispersions, fibers and thin films, and other systems strongly influenced
by the properties of their interfaces. Our group engages in research attempting
to acquire fundamental understanding of systems of this type and their
application to situations of current practical interest. RECENT AND CURRENT RESEARCH
THRUSTS INCLUDE:
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Dynamic surface tension and interaction of surfactant solutions with print media. The success of ink-jet printing lies in the appropriate interaction of the ink with the print medium over the time involved in the printing process. Ink-jet inks are complex formulations of dyes and surfactants in a carrier medium, while printing surfaces may be various types of treated or untreated paper or porous or swellable layers coated onto various backings. The dynamic interaction, inlcuding diffusion, adsorption, wicking and spreading as a function of system composition and morphology is under investigation.
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Mixed colloids. Here we are investigating the aggregation stability
behavior of and floc structure evolution in colloids which consist of more
than one dispersed species. One focus is on systems containing mineral
pigments together with emulsion droplets (representative of resin binder)
in aqueous media. These systems represent one type of water-based coatings
which may ultimately replace solvent-based coatings, with both environmental
and economic advantages.
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Gel-trapping of colloidal dispersions. The behavior of colloidal and supra-colloidal dispersions in visco-elastic media is under investigation. The objectives are to observe and predict sedimentation, diffusion and aggregation behavior in terms of dispersion type and the rheological properties of the medium.
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Surface energetics and adhesion. Surface energy characterization,
in particular acid-base characteristics, of solids is being conducted through
capillary measurements, inverse gas chromatography and atomic force microscopy. In particular, micro- and nano-patterned primer layers are being produced and characterized using the pulsed-force mode of AFM. The objective is to produce primers which produce strong adhesion between polymers and mineral surfaces while simultaneously promoting moisture resistance and corrosion inhibition. The data characterizing the primer surfaces are being used to correlate with adhesive performance and the mechanical properties.
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Particle-filled and fiber-reinforced composites. We are examining the properties of composite materials as they are influenced by the type, size, dispersion, and loading of different types of particles (and nanoparticles) and fibers in both thermoplastic and thermoset polymeric matrices as well as sol-gel coating systems. Both mechanical and optical properties are being examined. Novel schemes are being devised for reinforcement, including the development of new core-shell nanoparticulate reinforcements, and the development of new methods for the control of stress transfer at the particle- or fiber-matrix interface.
Members of the group
Recent News
from the group
The Short
Course in Surface and Colloid Science
J. Berg
Email -- berg@cheme.washington.edu
Web -- http://depts.washington.edu/chemeng/general/faculty.html
Berg Presentation for Chem E 515