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Title: Single-chain simulation of Ising density functional theory for weak polyelectrolytes
Conventional theories of weak polyelectrolytes are either computationally prohibitive to account for the multidimensional inhomogeneity of polymer ionization in a liquid environment or oversimplistic in describing the coupling effects of ion-explicit electrostatic interactions and long-range intrachain correlations. To bridge this gap, we implement the Ising density functional theory (iDFT) for ionizable polymer systems using the single-chain-in-mean-field algorithm. The single-chain-in-iDFT (sc-iDFT) shows significant improvements over conventional mean-field methods in describing segment-level dissociation equilibrium, specific ion effects, and long-range intrachain correlations. With an explicit consideration of the fluctuations of polymer configurations and the position-dependent ionization of individual polymer segments, sc-iDFT provides a faithful description of the structure and thermodynamic properties of inhomogeneous weak polyelectrolyte systems across multiple length scales.  more » « less
Award ID(s):
2234013
PAR ID:
10539604
Author(s) / Creator(s):
; ;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
159
Issue:
21
ISSN:
0021-9606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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