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Stretching an adsorbed polymer globule

Franck Celestini·Thoma Frisch·Xabier Oyharcabal
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Abstract

Using molecular dynamic simulation, we study the stretching of an adsorbed homopolymer in a poor solvent with one end held at a distance $z_e$ from the substrate. We measure the vertical force $f$ on the end of the chain as a function of the extension $z_e$ and the substrate interaction energy $w$. The force reaches a plateau value at large extensions. In the strong adsorption limit, we show that the plateau value increase linearly in $w$ in good agreement with a theoretical model. In the weak adsorption limit, a polymer globule with a layered structure is formed and elastically deformed when stretched. In both cases a simple theoretical model permits us to predict the relation between the necessary force to fully detach the polymer and its critical extension.

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Franck Celestini, Thoma Frisch, Xabier Oyharcabal. 2004-06-08. Stretching an adsorbed polymer globule. https://doi.org/10.1103/physreve.70.012801

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