This proposal is for a three-way collaboration between U. Minnesota, Princeton, and U. of Alabama, with different but mutually enhancing expertise in synthetic chemistry and materials science, to obtain needed information on the interfacial physical chemistry of amphophilic polymer dispersants. The specific approach is to study the direct effects of systematic variations os molecular weight, chemical structure, polymer architecture, and other factors which might possibly be used for tailoring amphophilic polymer dispersants, on the interactions that determine the macroscopic properties of colloidal dispersions. Effects of systematic variation of molecular characteristics of adsorbed layers of amphophilic block copolymers on the interaction forces between two such macroscopic layers will be studied. Polymers molecules with well-defined molecular weights and architectures will be synthesized by anionic polymerization and characterized with respect to block molecular weights, compositions, and architectures. Direct measurement of forces between adsorbed layers will be made. Theoretic modelling of the measured interaction profiles using self-consistent field theory will be carried out. With the measured and qualitatively modelled interactions having been determined, the response of macroscopic dispersion properties can be related in a direct way to molecular characteristics of the dispersion agents.
