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The European Physical Journal E

, Volume 17, Issue 3, pp 381–388 | Cite as

Multicanonical Monte Carlo simulations on intramolecular micelle formation in copolymers

  • Tsuyoshi Koga
Original Article

Abstract.

The formation of intramolecular micelles in copolymers with periodic sequence, where hydrophobic units (stickers) are periodically placed along the chain, is studied by using multicanonical Monte Carlo computer simulations for an off-lattice bead-rod model in three dimensions. With decreasing the temperature, a transition from random-coil conformations to micelles occurs and flower-type micelles are formed via the transition. The number of stickers forming a micelle core is limited by the excluded-volume effect of loop chains around micelle cores. By this effect, two intramolecular micelles are formed for long polymer chains with 60 bonds via the coil-to-micelle transition. By further decreasing the temperature, we find that another transition, i.e., a micelle-to-micelle transition, takes place. At this transition point, the two intramolecular micelles merge into one micelle. Furthermore, we extend the multicanonical MC method to study elastic properties of single polymer chains with strong attractive interactions under external force fields, and study how the intramolecular micellization affects the elastic property of single polymer chains.

PACS.

82.35.Jk Copolymers, phase transitions, structure 05.10.Ln Monte Carlo methods 82.70.Uv Surfactants, micellar solutions, vesicles, lamellae, amphiphilic systems, hydrophilic and hydrophobic interactions 

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Copyright information

© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2005

Authors and Affiliations

  • Tsuyoshi Koga
    • 1
  1. 1.Department of Polymer ChemistryGraduate School of Engineering, Kyoto UniversityKyoto

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