CAPTURE OR REPULSION OF TREATED NYLON PARTICLES BY AN ICE-WATER INTERFACE

In this contribution, we investigate the importance of surface propert ies in particle entrapment or rejection by an upward moving ice-water interface. Spherical nylon particles of diameter ranging from 3 x 10(- 3) to 5 x 10(-3) m are used. Some are untreated, some are coated with a thin layer of carbon or gold and some are soaked in ethanol for seve ral days before testing. According to the surface state, a particle ma y be more or less rejected under the same experimental conditions. For instance, nylon + carbon particles are more easily repulsed than nylo n particles. For nylon + gold particles, entrapment is favoured. These experimental results are discussed and compared to our theoretical wo rk based on the calculation of the different forces acting on untreate d and treated particles (disjoining force and viscous force).