Condensed Matter Physics, 2015, vol. 18, No. 2, 23802
DOI:10.5488/CMP.18.23802
arXiv:1506.03976
Title:
Adsorption of symmetric random copolymer onto symmetric random surface:
the annealed case
Author(s):
 
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A.A. Polotsky
(Institute of Macromolecular Compounds, Russian Academy of Sciences,
31 Bolshoy prospekt, 199004 Saint Petersburg, Russia; Saint Petersburg National Research University of Information Technologies,
Mechanics and Optics (ITMO University), 49 Kronverkskiy prospekt,
197101 Saint Petersburg, Russia)
,
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Adsorption of a symmetric (AB) random copolymer (RC) onto a
symmetric (ab) random heterogeneous surface (RS) is studied
in the annealed approximation by using a two-dimensional partially
directed walk model of the polymer. We show that in the symmetric
case, the expected a posteriori compositions of the RC and the
RS have correct values (corresponding to their a priori probabilities)
and do not change with the temperature, whereas second moments of
monomers and sites distributions in the RC and RS change. This indicates
that monomers and sites do not interconvert but only rearrange in
order to provide better matching between them and, as a result, a
stronger adsorption of the RC on the RS. However, any violation of
the system symmetry shifts equilibrium towards the major component
and/or more favorable contacts and lead to interconversion of monomers and sites.
Key words:
random copolymer, random surface, polymer adsorption, annealed approximation,
generating functions
PACS:
87.10.Hk, 82.35.Gh, 82.35.Jk
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