Response of capillary suspensions to external deformations

When a small amount (less than 1%) of a second immiscible liquid is added to the continuous phase of a suspension, the rheological properties of the mixture are dramatically altered from a fluid-like to a gel-like state or from a weak to a strong gel and the strength can be tuned in a wide range covering orders of magnitude [1]. The response of a capillary state suspension to steady and oscillatory stresses is examined in this current work. This suspension, where the secondary fluid does not preferentially wet the particles, is particularly sensitive to magnitude of deformation and shows varying characteristics with the amount of secondary fluid. These admixtures also show significant time varying behavior at constant oscillatory strain amplitudes with an initial increase in the network strength and then a sudden decrease in the strength as the network is destroyed.status: publishe