Polystyrene-poly(N,N-diethylamino ethyl methacrylate) (PS-PDEAEMA) particles with a core-shell morphology were prepared by seeded emulsion polymerization. Poly(oxyethylene) (POE) (n = 15 and 30) nonyl phenol and sodium lauryl sulfate (SLS) were used as emulsifiers. These two emulsifiers were selected in order to study the effect of nonionic and ionic emulsifiers on the reaction because of the basic character of DEAEMA. The core-shell morphology was investigated independently in the presence of water-soluble potassium persulfate (KPS) and of oil-soluble azobisisobutyronitrile (AIBN). The morphologic structure of the particles was studied using scanning electron microscopy and transmission electron microscopy. The latex particles and the polymers were characterized by differential scanning analysis, thermogravimetric analysis, and gel permeation chromatography.