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arXiv · 1109.5077

Thermodynamics of polymer adsorption to a flexible membrane

Steffen Karalus·Wolfhard Janke·Michael Bachmann
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Abstract

We analyze the structural behavior of a single polymer chain grafted to an attractive, flexible surface. Our model is composed of a coarse-grained bead-and-spring polymer and a tethered membrane. By means of extensive parallel tempering Monte Carlo simulations it is shown that the system exhibits a rich phase behavior ranging from highly ordered, compact to extended random coil structures and from desorbed to completely adsorbed or even partially embedded conformations. These findings are summarized in a pseudophase diagram indicating the predominant class of conformations as a function of the external parameters temperature and polymer-membrane interaction strength. By comparison with adsorption to a stiff membrane surface it is shown that the flexibility of the membrane gives rise to qualitatively new behavior such as stretching of adsorbed conformations.

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Steffen Karalus, Wolfhard Janke, Michael Bachmann. 2011-09-23. Thermodynamics of polymer adsorption to a flexible membrane. https://doi.org/10.1103/physreve.84.031803

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