Self-Salting Coacervates: Interfacial Tension Reveals a Critical-Like Self-Suppression of Complex Coacervation
- 1Centre de Recherche Paul Pascal (CRPP), UMR 5031, University of Bordeaux, CNRS
- 2UMR
- 3University of Bordeaux, CNRS, Bordeaux INP
Abstract
Complex coacervation is typically controlled via salt concentration, while the role of polymer concentration itself has received much less attention. Here, we show that increasing polyelectrolyte concentration can progressively suppress complex coacervation in a charge-stoichiometric, salt- free PDADMAC/PANa system. As polymer concentration increases, the coacervate phase swells while the polymer recovery stays nearly constant, and the compositions and densities of the coacervate and supernatant phases progressively converge. At = 400 mM, the macroscopic phase boundary vanishes and the system reaches a homogeneous, self-suppressed coacervation state. Over this range, the liquid–liquid interfacial tension decreases continuously toward zero following a critical-like power law with an exponent of 1.43 ± 0.03, close to the classical mean-field value of 3/2. These results show that polymer concentration is not merely a compositional variable, but can itself drive coacervation toward a critical-like, one-phase state by increasing salt-like screening from polymer-derived counterions, analogous to the effect of added salt.
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BibTeX
@misc{yu2026selfsalting,
title = {{Self-Salting Coacervates: Interfacial Tension Reveals a Critical-Like Self-Suppression of Complex Coacervation}},
author = {Yue Yu and Hongwei Li and Christophe Schatz and Jean-Paul Chapel},
howpublished = {ChemRxiv},
year = {2026},
month = sep,
doi = {10.26434/chemrxiv.15008981/v1},
url = {https://chemrxiv.org/doi/full/10.26434/chemrxiv.15008981/v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - Self-Salting Coacervates: Interfacial Tension Reveals a Critical-Like Self-Suppression of Complex Coacervation
AU - Yue Yu
AU - Hongwei Li
AU - Christophe Schatz
AU - Jean-Paul Chapel
PY - 2026
DA - 2026/09/17
PB - ChemRxiv
DO - 10.26434/chemrxiv.15008981/v1
UR - https://chemrxiv.org/doi/full/10.26434/chemrxiv.15008981/v1
AB - Complex coacervation is typically controlled via salt concentration, while the role of polymer concentration itself has received much less attention. Here, we show that increasing polyelectrolyte concentration can progressively suppress complex coacervation in a charge-stoichiometric, salt- free PDADMAC/PANa system. As polymer concentration increases, the coacervate phase swells while the polymer recovery stays nearly constant, and the compositions and densities of the coacervate and supernatant phases progressively converge. At = 400 mM, the macroscopic phase boundary vanishes and the system reaches a homogeneous, self-suppressed coacervation state. Over this range, the liquid–liquid interfacial tension decreases continuously toward zero following a critical-like power law with an exponent of 1.43 ± 0.03, close to the classical mean-field value of 3/2. These results show that polymer concentration is not merely a compositional variable, but can itself drive coacervation toward a critical-like, one-phase state by increasing salt-like screening from polymer-derived counterions, analogous to the effect of added salt.
ER -