Production of quasi-monodisperse emulsions with large droplets using a micromachined device

The development and operation of a modified method for the preparation of quasi-monodisperse (CV < 16%) emulsions are reported. The device uses a microfabricated-nozzle (MN) array, produced by micromachining technology, to achieve a higher rate of emulsification [76.8 m(3)/(m(2.)h)] than previously reported for microchannel (MC) emulsification methods. The dispersed phase is extruded into a continuous phase through the MN, and the emulsion droplets are formed by viscous drag force of the continuous phase. The droplet diameter decreased with an increase in the flow velocity and viscosity in the continuous phase, which was explained by the theoretical model. The range of droplet diameters produced (130 to 370 pm) was larger than in previously reported MC emulsification, membrane emulsification, and shear-rupturing methods.