Theoretical Condensed Matter Physics Jeffrey Sokoloff Professor Physics Department Executive Officer PhD Massachusetts Institute of Technology, 1967 (617)373-2931 3630jbs@neu.edu sokoloff@neu.edu Research Summary: "Microscopic Mechanisms for Friction" J. B. Sokoloff This work deals with theoretical studies of wear�less friction between solid surfaces. The methods of study involve both analytic methods based on scaling theory, numerical model studies and simulations. The combined use of these methods allows us to gain insights which would be impossible to obtain with one method alone. Two of the problems considered are studies of a proposed mechanism for the reduction of friction by a lubricant, based on collective pinning theory and studies of a mechanism for why the thin films in quartz crystal microbalance experiments, designed for studying friction, are able to slide under the exceedingly weak inertial forces exerted on the films when quartz crystal oscillates. I have begun to study a lubrication mechanism due to polymer brush coatings. In publication 5, it is shown that at suffciently light loads polymer brush coated surfaces can slide, with the load supported entirely by osmotic pressure, at a sufficiently large spatial separation so as to avoid entanglement, and hence static friction. J. B. Sokoloff, "Theory of Lubrication due to Poly-Electrolyte Polymer Brushes," unpublished. C. Daley and J.B. Sokoloff, "Theory of Static and Dynamic Friction due to Absorbed Molecules," submitted to Physical Review E. J. B. Sokoloff, "Superlubricity for Incommensurate, Crystalline and Disordered Interfaces," a chapter in a book, "Superlubricity," by A. Erdemir and J.M. Martin (Elsevier, Boston, 2007). J. B. Sokoloff, "Theory of Friction Between Neutral Polymer Brushes," Macromolecules; 2007; 40 (11) pp 4053-4058. J. B. Sokoloff, "Theory of the Effects of Multiscale Surface Roughness and Stiffness on Static Friction" Physical Review E73, 016104 (2006). Related links: Full description of Professor Sokoloff's reseach CIRCS |
