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Heteropolymers in a Solvent at an Interface

A. Maritan·M. P. Riva·A. Trovato
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Abstract

Exact bounds are obtained for the quenched free energy of a polymer with random hydrophobicities in the presence of an interface separating a polar from a non polar solvent. The polymer may be ideal or have steric self-interactions. The bounds allow to prove that a ``neutral'' random polymer is localized near the interface at any temperature, whereas a ``non-neutral'' chain is shown to undergo a delocalization transition at a finite temperature. These results are valid for a quite general a priori probability distribution for both independent and correlated hydrophobic charges. As a particular case we consider random AB-copolymers and confirm recent numerical studies.

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A. Maritan, M. P. Riva, A. Trovato. 1999-01-26. Heteropolymers in a Solvent at an Interface. https://arxiv.org/abs/cond-mat/9901292

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