9305286 Winey Rheometry is the most common and reliable technique for measuring viscoelastic properties of materials. This rheometer, a Rheometrics Solids Analyzer, satisfies the sample configuration requirements of many researchers on campus, in that it can accommodate molten polymers, glassy thin films, fibers, concentrated solutions, rubber, and composites. The processing equipment, includes a melt mixer for combining a variety of components and a small extruder to form samples for subsequent structural and mechanical evaluation. Throughout the School of Engineering and Applied Science and the School of Arts and Sciences, this new equipment will compliment the experimental techniques currently used by Penn faculty. In our research laboratories we prepare copolymer/homopolymer blends by using a volatile solvent, a practice which is avoided by industry, and evaluate the morphology and phase behavior using transmission electron microscopy and small angle x-ray scattering. With the proposed equipment, blends will be prepared without using a solvent and our extensive morphological studies will be related to new rheological studies. In another example, preceramic polymers are currently studied at Penn by using synthetic techniques elemental and thermal analysis, and wide angle x-ray scattering. The new equipment will provide a means of fabricating fibers, using the extruder, and studying the mechanical properties of the preceramic polymers, using the rheometer. Other research projects include: relating the percent crystallinity and conductivity of a conducting polymer with the viscoelastic properties of the materials, comparing the molecular motion in polymer blends as measured by both diffusion and zero shear viscosity, and testing theoretical models of ionomer solutions by neutron scattering and rheology. An important goal of this project is to make the research at Penn more relevant to industrial concerns by using similar processing techniques and g iving more emphasis to the interdependence of microscopic structure and macroscopic properties. ***
