COLL 385 |
| Jennifer Logan1, Brian Dorvel1, Raju Francis2, Sergei S Sheiko3, Yves Gnanou4, and Randolph S. Duran1. (1) Butler Polymer Laboratory, Department of Chemistry, University of Florida, Gainesville, FL 32611, (2) Department of Chemistry, St. Joseph's College, University of Calicut, Calicut, Kerala, 673008, India, (3) Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3290, (4) Laboratoire de Chimie des Polymeres Organiques, University of Bordeaux, ENSCPB, 16, Avenue Pey-Berland, Pessac, 33607, France |
| A series of three-arm star block copolymers were examined using Atomic Force Microscopy (AFM). These stars consisted of a polystyrene (PS) core composed of ca. 111 styrene units/branch with poly(ethylene oxide) (PEO) chains at the star periphery. Each star contained different amounts of PEO, varying from ca. 107-415 ethylene oxide units/branch. The stars were spread as thin films at the air/water interface on a Langmuir trough and transferred onto mica at various surface pressures. Circular domains representing aggregated molecules were observed at low pressures. Upon further compression, these domains underwent additional aggregation. Domain area and the number of molecules/domain increased with increasing pressure. In addition, it was found that longer PEO chains led to greater intermolecular separation and less aggregation. These AFM results correspond to attributes seen in the surface pressure-area isotherms of the stars. |
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Symposium in Memory of Arthur W. Adamson
8:30 AM-12:10 PM, Wednesday, March 31, 2004 Marriott -- Orange County 4, Oral
Division of Colloid and Surface Chemistry |