ANOMALOUS SURFACE-TENSION OF GROWING DROPLETS

We present an in situ measurement of the mean surface tension of a population of growing droplets. These droplets are formed by nucleation of the metastable phase in a slightly supersaturated binary fluid mixture near the consolute point. The system is submitted to a shear flow and the deformation of the droplets is deduced from small-angle light scattering. Data are compared to Rallison's predictions which allows the surface tension between a droplet and the bulk phase to be determined. The value obtained under these conditions is one order of magnitude larger than the equilibrium value. This result is consistent with previous observations of anomalously shear-resistant critical droplets made by Goldburg near the critical point.