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Polydisperse star polymer solutions

Christian von Ferber·Arben Jusufi·Martin Watzlawek·Christos N. Likos·Hartmut Lowen
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Abstract

We analyze the effect of polydispersity in the arm number on the effective interactions, structural correlations and the phase behavior of star polymers in a good solvent. The effective interaction potential between two star polymers with different arm numbers is derived using scaling theory. The resulting expression is tested against monomer-resolved molecular dynamics simulations. We find that the theoretical pair potential is in agreement with the simulation data in a much wider polydispersity range than other proposed potentials. We then use this pair potential as an input in a many-body theory to investigate polydispersity effects on the structural correlations and the phase diagram of dense star polymer solutions. In particular we find that a polydispersity of 10%, which is typical in experimental samples, does not significantly alter previous findings for the phase diagram of monodisperse solutions.

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Christian von Ferber, Arben Jusufi, Martin Watzlawek, Christos N. Likos, Hartmut Lowen. 2000-07-31. Polydisperse star polymer solutions. https://doi.org/10.1103/physreve.62.6949

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