Synthesis of monodisperse, re-dispersable polymer particles by one-step high solid emulsion polymerization in the presence of reactive surfactant

In this study, monodispersed and re-dispersed poly (methyl methacrylate) (PMMA) particles were prepared by high solid content (50 wt%) macroemulsion polymerization using commercial macromonomer (Emulsogen APS 100) as a reactive surfactant (surfmer). Highly monodispersed, re-dispersed PMMA particles with sizes around 300 nm were obtained using this process. The effect of recipe composition including surfmer content, monomer/water ratio and electrolyte concentration on particle formation and growth were also investigated. Compared to classical macroemulsion polymerization theory, the formation of particles was found different. The number of formed particles firstly increased to a maximum value, then rapidly decreased to reach a constant value stabilized at around 1/5 of the maximum particle number. The particle coagulation theory was used to explain the process of particle formation and growth. The relationship between polymer particle size distribution and particle coagulation was also examined and the results were discussed. The proposed method would probably find applications in industrial production of monodisperse particles.