Sergei Egorov, at the University of Virginia, is supported by the Theoretical and Computational Chemistry Program to pursue research in supercritical fluids and their uses as a tunable media for chemical reactions and materials processing. The project deals with the theoretical and computational simulation of diblock copolymers, such as partially fluorinated alkane chains, in a supercritical carbon dioxide fluid. The diblock copolymer is modeled as a chain of fluorinated and hydrogenated units which may exhibit bond bending or torsional distortions. Nonbonded units interact via Lennard Jones potentials. The fluid is modeled by treating the carbon dioxide molecule as three partial charges interacting with neighbors via coulomb and Lennard-Jones potentials. Specific phenomena to be modeled include density-induced formation and disintegration of micellar aggregates, a statistical mechanical treatment of sterically stabilized nanoparticles and the study of ionic mobility in supercritical fluids. Long-term interest is in understanding how environmentally friendly supercritical fluids may be used for chemical and materials processing.
This project deals with understanding how to replace conventional liquid solvents, currently used in the chemical industry, with environmentally friendly nontoxic, nonflammable, abundant and cheap supercritical solvents such as carbon dioxide. The work will proceed by understanding the structure and dynamics of supercritical fluids at the molecular level by the development and implementation of new theoretical and computational methods. Activity includes training of students in nanoscale materials processing and preparing them for entry into industry.