Polymer at Surface

Adsorption of highly branched polymers

The tension in branched polymer backbones due to adsorption on surface can break carbon-carbon bonds of molecular brushes. We combine theoretical analysis, molecular dynamics simulation, and experiments to understand the dependence of adsorption process on side-chain length, solvent quality, and spreading parameter. We are developing theories and carrying out computer simulation to describe the distributed tension in these moelecules.

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1. "Adsorption-Induced Scission of Carbon-Carbon Bonds" by S. S. Sheiko, F. Sun, A. Randall, D. Shirvanyants, M. Rubinstein, H. Lee, and K. Matyjaszewski, Nature 440, 191-194 (2006).

2. "Flow-Enhanced Epitaxial Ordering of Brush-Like Macromolecules on Graphite" by H. Xu, S. S. Sheiko, D. Shirvanyants, M. Rubinstein, K. L. Beers, and K. Matyjaszewski, Langmuir 22, 1254-1259 (2006).

 

Architecture-induced mixing of polymer blends at surfaces

Architecturally different polymers form phase-separated domains when mixed together under certain conditions on surfaces. We investigate the formation and growth mechanism of this phase separation theoretically and observe the effect of various experimental parameters on the domain structure.

Polymer spreading on a surface

Polymer can spread on solid substrate to form monolayer-like film. We monitor such spreading process by using AFM technique and develop a theory of polymer dynamics on surface.