Electromagnetic, chemical and thermo-mechanical processing can be applied to the fabrication of polymeric materials which react to external fields such as stress, temperature, moisture, pH, electric or magnetic fields to optimise properties. In this article, the application of the pulsed electromagnetic field in an immiscible liquid phase is reviewed. The droplet behaviour of polymer emulsion's liquid phases is enriched with significant complex phenomena. In emulsion, droplet break-up, size evolution, coalescence, coarsening, flocculation and interfacial interaction among droplets are assessed as a function of processing. This review was submitted as part of the 2018 Materials Literature Review Prize of the Institute of Materials, Minerals and Mining run by the Editorial Board of MST. Sponsorship of the prize by TWI Ltd is gratefully acknowledged.