Chemical and Biomolecular Research Papers -- Faculty Authors Series


Date of this Version



Published by American Institute of Physics. Appl. Phys. Lett. Vol. 80, No. 23, 10 June 2002. © 2002 American Institute of Physics. Permission to use.


Structure of complex fluid at mesoscales is influenced by interfacial effects. We describe the dynamic response in such films to sudden change in interfacial tension. In a self-assembled block copolymer film, the monolayer of 15 nm diam cylindrical discrete phases close to the surface commence to sink at an average rate of 0.16 nm/day in response to the interfacial tension change. Surprisingly, this spontaneous planarization occurs, even though the cylinders are covalently stitched to the matrix. A simple model explains the observed behavior. The observation may lead to approaches to tailor the structure of mesoscale thin films of complex fluids for long-range order that are desirable for nanoscale device fabrication.