ABSTRACT Proposal Number: 9624293 PI: Koelling This ward is for an integrated career development plan to educate junior high, senior high, undergraduate, and graduate students in the field of rheolgical behavior of complex fluids and conduct research on the extensional rheology of polymers. The research will involve four different extensional rheometers. These rheometers will be used to study the extensional properties of polymer solutions over a range a range of temperatures. This research is focused on determining the properties necessary to characterize the behavior of viscoelastic fluids. It will address a range of issues such as what is the molecular conformation and steady-state extensional viscosity of a polymer undergoing large Henky strains and whether existing constitutive equations are adequate for describing shear and shear-free material functions of viscoelastic fluids. This information is of fundamental importance to many polymer processing operations including fiber spinning, blow molding, and injection molding and in a variety of other phenomena including turbulent drag reduction, jet stability, anti-misting and flow through porous media. An ambitious educational plan has been formulated. Demonstrations will be developed to introduce students to the relationship between rheology and the behavior of materials in everyday use. Examples include elasticity of rubber bands, Weissenberg effects in viscoelastic fluids such as cake batter and scrambled eggs, die swell with shampoos and yield stresses developed in mayonnaise and ketchup. The PI plans to work with high school students in developing science fair projects and also plans to develop an interdisciplinary course and laboratory experience for both undergraduate and graduate students interested in the rheology of foods bio-materials, colloids, emulsions, foams, polymer melts, polymer solutions, elastomers, composites, waxes and metals.
