Emulsion Solidification: Influence of the Droplet Size of the Water-in-Oil Emulsion on the Generated Particle Size

The solidification or crystallization characteristics of water-in-oil (w/o) emulsion drops generated from the capillary in stagnant coolant, here pure water, was investigated. The emulsions were prepared at different energy inputs by using a rotor stator and then pumped through a single orifice with the help of a syringe pump at a constant velocity. The uniform drops from this w/o emulsion were formed at the orifice exit which were then solidified in the coolant at a temperature below the freezing point of oil. The higher the energy input in the emulsification process, the lower was the size of water droplets distributed in the emulsion. The smaller water droplets in the emulsion affected the size of the drops from the orifice which then turned into solid particles. The water droplet distribution in the emulsion and the orientation or location within the solid particles were investigated and the ultimate effects on the particle formation from these emulsions observed.