Persistent droplet motion in liquid-liquid dewetting.

When a nonvolatile liquid film dewets from a partly compatible liquid substrate, the advancing dewetting front leaves behind droplets formed through a Rayleigh instability mechanism at its rim. We have found that these droplets continue to move in the direction of the dewetting front for extended periods (of order one day) with an initial droplet velocity varying linearly with the droplet size, and a displacement varying logarithmically with time. We attribute this persistent motion to a transient surface tension gradient on the substrate liquid surface trailing the dewetting front.

Alternative dewetting pathways of thin liquid films.

An alternative pathway for the initiation of dewetting in thin metastable films of partially miscible liquid mixtures is described. In this pathway, phase separation is followed by a dewetting process at the interface between the two phases. Dewetting proceeds (from the sample edges inward) as holes form.