The goal of this project is to gain a more complete understanding of structure/property/performance interrelationships of water-soluble polymers which can aid industry in commercial production of polymers which are more efficient than those presently used. During the past the following have been accomplished: synthesis of model dextran-g-poly(acrylamide-co-sodium acrylates,5548 ); synthesis of model dextran-g-poly(acrylamide-co-sodium-2-acrylamido-2-methylpropane sulfonates,5548 ); characterization of model copolymers by elemental analysis, C-13NMR, and viscometry; study of dilute solution properties of the models including the effects of temperature, salt, pH; rheological studies of model graft copolymers; development of mathematical models, new calibration functions, analytical methods, and data acquisition techniques for aqueous size exclusion chromatography; application of quasielastic light scattering techniques to the study of hydrodynamic volume concepts; preferential and overall solvation studies of AN/NaA and AM/NaAMPS copolymers; study of phase behavior of model polymers in mono- and multivalent electrolytes at different polymer and salt concentrations as a function of temperature; education and training of students in basic energy research.