CPIMA / INSTITUTE OF APPLIED MACROMOLECULAR CHEMISTRY,
UNIVERSITY OF STUTTGART, GERMANY

In continuation of a collaboration between Prof. Alice Gast and Prof. Gerald Fuller of the Department of Chemical Engineering at Stanford University and Prof. Claus Eisenbach of the Institute of Applied Macromolecular Chemistry of the University of Stuttgart in Stuttgart, Germany, Prof. Eisenbach is presently spending his sabbatical at the Department of Chemical Engineering of Stanford University.

There are several research areas to be explored in collaboration with the Gast and Fuller groups that are related to the conformation of rod-like macromolecules in solution and their rheological behavior as well as their miscibility with coil macromolecules in ionomer blends. The rod polymers as well as the ionomer blends have been synthesized and characterized at Prof. EisenbachÕs laboratories in Germany. It has been found In previous joint studies that the mechanical properties of ionomer blends are directly related to the Flory exponent of the rod-like blend component of tuned rigidity. Monolayer studies of sulfonated poly(p-phenylenes) have shown surface pressure induced isotropic Ð nematic phase transitions and non-Newtonian rheology.

As to the collaboration with the Gast group, the aim is to study the molecular structure and dynamics of rigid, semi-rigid and flexible polymer molecules in solution, gels and blends by combining a variety of light and x-ray scattering techniques. One aspect is to determine the conformation of sulfonated poly(p-phenylenes) in the form of the t-butyl ester, free acid and ionomer in order to understand the phase behavior and anisotropies in acid/base ionomer blends that result from blending the rod molecule with a base random coil polymer. In this connection, blends with increasing rod volume fraction or increasing length of the rod molecule will be investigated as well.

As to the collaboration with the Fuller group, the study of the dynamics of rod-like polymer chains constrained in two dimensions will be further persued. The problem of nematic order in two dimensions will be studied with a series of rod molecules of defined average length and rigidity. In this context, the interaction of the sulfonic side groups or pyridine moieties of the condensed rod-like molecules with monomeric and polymeric counterions in the subphase will be studied as well.