Characterizing polymers through molecular visualization

POLY 632

Sergei S. Sheiko, sergei@email.unc.edu, Frank C. Sun, Jamie R. Boyce, jboyce@email.unc.edu, and Sherryl Y. Yu. Department of Chemistry, University of North Carolina at Chapel Hill, CB# 3290 Venable Hall, Chapel Hill, NC 27599-3290
In recent years, atomic force microscopy (AFM) has been successfully used for visualization of both natural and synthetic macromolecules. The unique advantage of AFM is that one obtains molecular dimensions in direct space affording more opportunities for statistical analysis. The role of molecular visualization has grown to be especially profound with the synthesis of complex designer macromolecules whose structures are difficult to confirm using conventional characterization techniques such as light spectroscopy and scattering. This is especially true for molecules that are branched, heterogeneous, and polydisperse. Here, molecular visualization represents a very effective tool as it provides not only pictorial evidence for the molecular architecture, but also enables characterization of molecular conformation and processes. We will demonstrate the use of AFM for understanding physical properties of branched macromolecules by monitoring conformational transitions and mechanochemical reactions on surfaces.