Polymeric nanoparticles and colloids have generated a great deal of interest for their realized and potential applications in a variety of fields.^1,2  Polymer colloids can be used to deliver therapeutics or imaging aids to specific targets in the body^3–6  or to probe biological responses to foreign objects.⁷  Those which respond to chemical or physical stimuli can assemble to create nanocircuits or electronic displays,^8,9  and their propulsion behavior can give insights into the microrheology of their environment.^10,11  In other systems, immiscible mixtures can be compatibilized upon the introduction of polymer colloids which act as interfacial property modifiers.^12,13  Many of these applications require polymer colloids with anisotropic surface chemistries, complex internal morphologies, or specific surface charges. In order to be utilized in industrial applications, these colloids must be produced at large scale using an economical process.