Synthesis of monodisperse crosslinked St-PEG200DMA copolymeric microspheres
Dispersion copolymerization of styrene with polyethely en e glycol 200-dimethacrylae as crosslinking agent was carried out by using poly (N-vinylpy rrolidone), 2,2-azo-bisisobutyronitrile as the stabilizer and initiator, respectively. Highly monodisperse microspheres were prepared by the o ne-step method of dispersion copolymerization.The effects of the concentration of crosslinking agent on the microsphere morphology and copolymerization rate we re studied.It was found that the crosslinking agent played an important role on the particle morphology and system stability.When the concentration of crosslink ing agent was below 2.0%(mass) of styrene, all the microspheres were spherical with smooth surface. However, after the concentration reached 2.5%(mass) or hig her, monodisperse microspheres with flower-liked wrinkles on the surface were o btained.