COLL 108 |
| Vladimir Tsukruk, Department of Materials Science & Engineering, Department of Materials Science & Engineering, Iowa State University, 3155 Gilman Hall, Ames, IA 50011-2714 |
| We report results on microtribological studies of chemically grafted nanoscale polymer layers of different architecture with thickness below 30 nm. We fabricated the molecular lubrication coatings from elastomeric tri-block copolymers and binary polymer brushes. We observed a significant reduction of friction forces and an increase of the wear stability when a minute amount of oil was trapped within the grafted polymer layer. These polymer gel layers exhibited a very steady friction response and a small value of the coefficient of friction as compared to the initial polymer coating. A polymer "triplex" coating has been formed by a multiple grafting technique. The unique design of this layer includes a hard-soft-hard architecture with a compliant rubber interlayer mediating localized stresses transferred through the topmost hard layer. This architecture provides a non-linear mechanical response under a normal compression stress and allows additional dissipation of mechanical energy via the elastic rubber interlayer. |
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Molecular Tribology
Division of Colloid and Surface Chemistry |