Light Scattering Experiments in a Gel Saturated with a Liquid Mixture

Abstract

When a binary mixture is quenched through its critical point, domains of differing composition grow in composition contrast and in spatial size. As the process proceeds, droplets form and coalesce. Finally gravity separates the two phases and a sharp interface appears between them. Our concern here is how this scenario is modified when the liquid mixture is saturating a gel. Light scattering results are discussed in this paper^†; in the following one, S. Satija describes neutron scattering experiments which probe phase separation in the gel at smaller length scales. Both sets of experiments suggest that the gel in effect imposes a static random field, or chemical potential, on the mixture.