Glass Transition and Yielding of Ultrasoft Charged Spherical Micelles

Autor(en)

Roshan Akdar Mohamed Yunus, Utku Gürel, Aleksander Guzik, Philippe Dieudonné-George, Marc C.A. Stuart, Christos N. Likos, Patrizio Raffa, Domenico Truzzolillo, Andrea Giuntoli, Daniele Parisi

Abstrakt

Colloids are widely used as model systems to study the glass transition, with much research focused on hard or soft neutral colloids and their mixtures. However, the glass transition of soft-charged spherical colloids and its dynamic effects remain underexplored. This study assesses the glass transition of polymeric multiarm charged soft colloids using shear rheology, coarse-grained molecular dynamics (MD) simulations, and X-ray scattering. Strong particle-particle correlations, driven by electrostatic interarm repulsion, inhibit Newtonian behavior in the dilute regime. The liquid-to-glass transition occurs at just 0.25 wt %, marked by weak caging and minimal interdigitation of arms, as evidenced by particle contact analysis in MD simulations and the strong frequency dependence of the dynamic moduli. Particle shells interdigitate only well within the glassy regime, leading to a nearly frequency-independent rheological response. The weak volume fraction dependence of the yield stress sets these charged systems among the softest colloids reported in the literature.

Organisation(en)

Computergestützte Physik und Physik der Weichen Materie

Externe Organisation(en)

University of Groningen, Université Montpellier 2

Journal

Macromolecules

Anzahl der Seiten

16

ISSN

0024-9297

DOI

https://doi.org/10.1021/acs.macromol.4c03215

Publikationsdatum

04-2025

Peer-reviewed

Ja

ÖFOS 2012

103015 Kondensierte Materie, 104011 Materialchemie

ASJC Scopus Sachgebiete

Organic Chemistry, Polymers and Plastics, Inorganic Chemistry, Materials Chemistry

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/c5c79624-8876-43b4-ad8a-7ddf84b9f3a6