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arXiv · 1707.09401

Interparticle hydrogen bonding can elicit shear jamming in dense suspensions

Nicole James·Endao Han·Justin Jureller·Heinrich Jaeger
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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.

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Nicole James, Endao Han, Justin Jureller, Heinrich Jaeger. 2017-07-28. Interparticle hydrogen bonding can elicit shear jamming in dense suspensions. https://doi.org/10.1038/s41563-018-0175-5

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