Bulk-like viscosity and shear thinning during dynamic compression of a nanoconfined liquid
نویسندگان
چکیده
The viscosity of liquids under nanoconfinement remains controversial. Reports range from spontaneous solidification to no change in the viscosity at all. Here, we present thorough measurements with a small-amplitude linear atomic force microscopy technique and careful consideration of the confinement geometry, to show that in a weakly interacting liquid, average viscosity remains bulk like, except for strong shear thinning once the liquid is confined to less than four molecular layers. Overlaid over this bulk-like viscous behavior are stiffness and damping oscillations, indicating non-continuum behavior, as well as an elastic response when the liquid is allowed to order in the confinement gap.
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