TY - JOUR
T1 - Dramatic effect of fluid chemistry on cornstarch suspensions
T2 - Linking particle interactions to macroscopic rheology
AU - Oyarte Galvez, Loreto
AU - de Beer, Sissi
AU - van der Meer, Devaraj
AU - Pons, Adeline
PY - 2017/3/17
Y1 - 2017/3/17
N2 - Suspensions of cornstarch in water exhibit strong dynamic shear-thickening. We show that partly replacing water by ethanol strongly alters the suspension rheology. We perform steady and non-steady rheology measurements combined with atomic force microscopy to investigate the role of fluid chemistry on the macroscopic rheology of the suspensions and its link with the interactions between cornstarch grains. Upon increasing the ethanol content, the suspension goes through a yield-stress fluid state and ultimately becomes a shear-thinning fluid. On the cornstarch grain scale, atomic force microscopy measurements reveal the presence of polymers on the cornstarch surface, which exhibit a co-solvency effect. At intermediate ethanol content, a maximum of polymer solubility induces high microscopic adhesion which we relate to the macroscopic yield stress.
AB - Suspensions of cornstarch in water exhibit strong dynamic shear-thickening. We show that partly replacing water by ethanol strongly alters the suspension rheology. We perform steady and non-steady rheology measurements combined with atomic force microscopy to investigate the role of fluid chemistry on the macroscopic rheology of the suspensions and its link with the interactions between cornstarch grains. Upon increasing the ethanol content, the suspension goes through a yield-stress fluid state and ultimately becomes a shear-thinning fluid. On the cornstarch grain scale, atomic force microscopy measurements reveal the presence of polymers on the cornstarch surface, which exhibit a co-solvency effect. At intermediate ethanol content, a maximum of polymer solubility induces high microscopic adhesion which we relate to the macroscopic yield stress.
U2 - 10.1103/PhysRevE.95.030602
DO - 10.1103/PhysRevE.95.030602
M3 - Article
SN - 2470-0045
VL - 95
JO - Physical review E: covering statistical, nonlinear, biological, and soft matter physics
JF - Physical review E: covering statistical, nonlinear, biological, and soft matter physics
IS - 3
M1 - 030602
ER -