STATIC AND DYNAMIC LIGHT-SCATTERING OF DILUTE MAGNETORHEOLOGICAL EMULSIONS

The structure formation and dynamics of a dilute, monodisperse ferrofl uid emulsion under the influence of an external magnetic field have be en investigated using static and dynamic light scattering techniques. In the absence of an external field, the spherical emulsion particles behave as a dilute system of hard spheres where the static light scatt ering is dominated by the droplet form factor and the dynamic light sc attering provides the diffusion coefficient due to their Brownian moti on. An applied magnetic field induces a magnetic dipole moment in each droplet. Static light scattering is used to study the time dependence of the structure formation caused by the dipole-dipole interaction as a function of the field strength. The change of the dynamic propertie s due to chain formation is studied by dynamic light scattering.