English

Charge Regulation of Polyelectrolyte Gels: Swelling Transition

Soft Condensed Matter 2023-08-02 v1 Biological Physics Chemical Physics

Abstract

We study the effects of charge-regulated acid/base equilibrium on the swelling of polyelectrolyte gels, by considering a combination of the Poisson-Boltzmann theory and a two-site charge-regulation model based on the Langmuir adsorption isotherm. By exploring the volume change as a function of salt concentration for both nano-gels and micro-gels, we identify conditions where the gel volume exhibits a discontinuous swelling transition. This transition is driven exclusively by the charge-regulation mechanism and is characterized by a closed-loop phase diagram. Our predictions can be tested experimentally for polypeptide gels.

Keywords

Cite

@article{arxiv.2304.01818,
  title  = {Charge Regulation of Polyelectrolyte Gels: Swelling Transition},
  author = {Bin Zheng and Yael Avni and David Andelman and Rudolf Podgornik},
  journal= {arXiv preprint arXiv:2304.01818},
  year   = {2023}
}