The flow induced phase inversion phenomenon is applied to the phase inversion emulsification of high molecular weight epoxy polymer melt to obtain sub-micron particles. It is found that molecular surfactants could not be used to obtain the initial [water-in-polymer melt] emulsion. Polymeric surfactants, hydrophobically modified water soluble polymers have to be used for this purpose. The molecular structure of the polymeric surfactant is important in obtaining smaller emulsion droplets for a given polymer melt. Depending on the processing history, either a 'powdery dispersion' containing 10 wt% water or water continuous dispersion can be obtained. Sub-micron epoxy particles can be obtained, even at relatively low polymeric surfactant concentrations, by subjecting the [water-in-polymer melt] emulsion to very high deformation rates using a model static mixer called Multiple Expansion Contraction Static Mixer. This mixer is essentially a series of short capillaries separated by flow dividers. In order to provide constant flow rate at very high pressures, an injection moulding machine is used.