Structure of salted and discharged globules of hydrophobic polyelectrolytes adsorbed from aqueous solutions

Authors

  • Oleksandr Trotsenko,

    1. Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Ave., Potsdam, New York 13699-5810
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  • Yuri Roiter,

    1. Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Ave., Potsdam, New York 13699-5810
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  • Sergiy Minko

    Corresponding author
    1. Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Ave., Potsdam, New York 13699-5810
    • Department of Chemistry and Biomolecular Science, Clarkson University, 8 Clarkson Ave., Potsdam, New York 13699-5810
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Abstract

In this article, we compare structures of protonated poly(2-vinylpyridine) globules (2D compact coils on the surface) adsorbed on the mica surface from aqueous solution when the shrinking is brought about either by discharging the molecules at an elevated pH or by adding monovalent and polyvalent salts. We study the structure of the PE coils using in situ atomic force microscopy experiments in aqueous solutions in a liquid cell. The abrupt coil-to-globule transition caused by pH changes and the discharge of polymer chains resulted in compact globules. If the pH corresponding to extended coil conformation remains unchanged, the coil shrinks due to the added salt. The size of the globule in the latter case corresponds to the unperturbed dimension of the polymer coil. There is no essential difference in the dimensions of the globules as obtained in the presence of monovalent and multivalent counterions for the studied ionic strength. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1623–1627, 2010

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