Viscoelasticity of depletion-induced gels in emulsion-polymer systems

Using rheometry and light scattering, we have studied the viscoelasticity o f gels formed by the kinetically arrested phase separation in an emulsion-p olymer mixture; to prevent the gels From collapsing under their own weight, we have used an isopycnic solvent. At constant osmotic pressure (set by th e polymer concentration) and droplet volume fractions phi well, above the g elation transition, we find the elastic modulus to increase roughly linearl y with phi, indicating an entropic elasticity based on the cluster packing.