Structure of phase-separated athermal colloid-polymer systems in the protein limit

Nathan A. Mahynski, Barry Irick, Athanassios Z. Panagiotopoulos

Research output: Contribution to journalArticle

15 Scopus citations

Abstract

Structural features of phase-separated athermal colloid-polymer mixtures in the so-called "protein limit," where polymer chain dimensions exceed those of the colloid, are investigated using grand canonical Monte Carlo simulations on a fine lattice. Previous work has shown that this model accurately captures the phase behavior of experimental systems, and that colloids with sufficiently small diameters, σc, relative to that of the monomeric segments, σs, phase separate more readily than their large-diameter counterparts. In the present study, we directly connect colloid and polymer structure with their phase behavior by investigating these solutions along their binodal curves; we also explore the role of colloid surface curvature in destabilizing such solutions. Our findings suggest that simple consideration of an additional depletion radius, on the order of the σs, leads to a quantitatively accurate prediction of the division between stable and unstable ranges of d=σs/ σc. We compare these results to continuum models with different bonding potentials between monomer segments in order to elucidate the significance of the lattice model's bond fluctuations and inherently coarse colloid surface. In a number of cases, the continuum models deviate both qualitatively and quantitatively from the lattice results, but the binodals of the continuum models are presently not known, making a strong conclusion about these differences impossible.

Original languageEnglish (US)
Article number022309
JournalPhysical Review E - Statistical, Nonlinear, and Soft Matter Physics
Volume87
Issue number2
DOIs
StatePublished - Feb 27 2013

All Science Journal Classification (ASJC) codes

  • Statistical and Nonlinear Physics
  • Statistics and Probability
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Structure of phase-separated athermal colloid-polymer systems in the protein limit'. Together they form a unique fingerprint.

Cite this