Strictly two-dimensional self-avoiding walks: Thermodynamic properties revisited

  • N. Schulmann
  • H. Xu
  • H. Meyer
  • P. Polińska
  • J. Baschnagel
  • J. P. Wittmer
Regular Article

Abstract

The density crossover scaling of various thermodynamic properties of solutions and melts of self-avoiding and highly flexible polymer chains without chain intersections confined to strictly two dimensions is investigated by means of molecular dynamics and Monte Carlo simulations of a standard coarse-grained bead-spring model. In the semidilute regime we confirm over an order of magnitude of the monomer density ρ the expected power law scaling for the interaction energy between different chains eintρ21/8, the total pressure Pρ3 and the dimensionless compressibility gT = limq→0S(q) ∼ 1/ρ2. Various elastic contributions associated to the affine and non-affine response to an infinitesimal strain are analyzed as functions of density and sampling time. We show how the size ξ(ρ) of the semidilute blob may be determined experimentally from the total monomer structure factor S(q) characterizing the compressibility of the solution at a given wave vector q . We comment briefly on finite persistence length effects.

Keywords

Soft Matter: Polymers and Polyelectrolytes 

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Copyright information

© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • N. Schulmann
    • 1
  • H. Xu
    • 2
  • H. Meyer
    • 1
  • P. Polińska
    • 1
  • J. Baschnagel
    • 1
  • J. P. Wittmer
    • 1
  1. 1.Institut Charles SadronUniversité de Strasbourg & CNRSStrasbourg Cedex 2France
  2. 2.LCP-A2MC, Institut Jean BarriolUniversité de Lorraine & CNRSMetz Cedex 03France

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