Templating hollow polymeric spheres from catanionic equilibrium vesicles: Synthesis and characterization

Hollow polymer spheres of styrene and divinyl benzene can be templated from catanionic equilibrium vesicles formed by cetyltrimethylammonium tosylate (CTAT) and sodium dodecylbenzenesulfonate (SDBS) or cetyltrimethylammonium bromide (CTAB) and sodium octyl sulfate (SOS). Characterization by many methods suggests the microstructure of the equilibrium vesicle template is left largely intact in the final polymer product. The particles have an average radius of ca. 60 nm and a membrane shell less than 10 nm thick. The cross-linked hollow polymer vesicles are robust and withstand complete drying and resuspension in water with no apparent change in microstructure. The polymer membrane surfaces can be functionalized by sulfonation or surfactant adsorption, and this functionalization prevents aggregation of the polymer particles when they are resuspended in water.