The European Physical Journal E

, Volume 22, Issue 4, pp 325–333 | Cite as

Behavior of block-polyampholytes near a charged surface

  • R. Messina
Regular Articles


The behavior of polyampholytes near a charged planar surface is studied by means of Monte Carlo simulations. The investigated polyampholytes are overall electrically neutral and made up of oppositely charged units (called blocks) that are highly charged and of the the same length. The influence of block length and substrate's surface-charge-density on the adsorption behavior is addressed. A detailed structural study, including local monomer concentration, monomer mean height, and transversal chain size, is provided. It is demonstrated that adsorption is favored for long enough blocks and/or high enough Coulomb interface-ion couplings. By explicitly measuring the chain size in the bulk, it is shown that the charged interface induces either a swelling or a shrinkage of the transversal dimension of the chain depending, in a non trivial manner, on the block length.


82.35.Gh Polymers on surfaces; adhesion  82.35.Jk Copolymers, phase transitions, structure 87.15.Aa Theory and modeling; computer simulation  


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Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2007

Authors and Affiliations

  1. 1.Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1DüsseldorfGermany

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