Delayed recovery in a dense suspension of core-shell attractive particles

Justine Henry; Ludovic Feige; Clara Paillard; Thibaut Divoux

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arXiv · 2410.11102

Delayed recovery in a dense suspension of core-shell attractive particles

Justine Henry·Ludovic Feige·Clara Paillard·Thibaut Divoux

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Abstract

Soft particulate glasses are dense suspensions of jammed particles that flow like liquids under external shear and recover their solid-like properties almost instantly upon flow cessation. Here, we consider a dense suspension of core-shell attractive particles whose polymer brush allows for a delayed recovery that we monitor by time-resolved mechanical spectroscopy. Viscoelastic spectra recorded upon flow cessation show a striking power-law behavior and can be rescaled onto a master curve that hints at a time-connectivity superposition principle. Additionally, the non-linear response of this soft glass, measured at various aging times, shows a ductile-to-brittle transition, which suggests that the interactions between the particles display a progressive repulsive-to-attractive transition. These results depict an original scenario for the delayed recovery involving a time-dependent interaction potential in which attractive hydrophobic forces are only activated when neighboring particles deform their polymer shell and come in close contact.

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Justine Henry, Ludovic Feige, Clara Paillard, Thibaut Divoux. 2024-10-14. Delayed recovery in a dense suspension of core-shell attractive particles. https://arxiv.org/abs/2410.11102

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