Interparticle hydrogen bonding can elicit shear jamming in dense suspensions

TL;DR

This study reveals that interparticle hydrogen bonding, influenced by surface chemistry, can induce shear jamming in dense suspensions, expanding understanding of non-Newtonian fluid behaviors.

Contribution

It demonstrates that hydrogen bonding between particles can trigger shear jamming, a novel insight into the mechanisms behind non-Newtonian suspension behaviors.

Findings

Hydrogen bonding facilitates shear jamming in suspensions.

Surface chemistry controls the transition from shear thickening to shear jamming.

Atomic force microscopy shows increased friction due to hydrogen bonds.

Abstract

Dense suspensions of hard particles in a liquid can exhibit strikingly counter-intuitive behavior, such as discontinuous shear thickening (DST) [1-8] and reversible shear jamming (SJ) into a state with finite yield stress [9-13]. Recent studies identified a stress-activated crossover from hydrodynamic interactions to frictional particle contacts to be key for these behaviors [2-4, 6-8, 10, 14]. However, many suspensions exhibit only DST and not SJ. Here we show that particle surface chemistry can play a central role in creating conditions that allow for SJ. We find the system's ability to form interparticle hydrogen bonds when sheared into contact elicits SJ. We demonstrate this with charge-stabilized polymer microspheres and non-spherical cornstarch particles, controlling hydrogen bond formation with solvents. The propensity for SJ is quantified by tensile tests [13] and linked to an enhanced friction by atomic force microscopy. Our results extend the fundamental understanding of the SJ mechanism and open new avenues for designing strongly non-Newtonian fluids.