Macromolecules, Vol.39, No.16, 5381-5384, 2006
Synthesis of ultrahigh surface area monodisperse porous polymer nanospheres
Synthesis of vinyl benzyl chloride (VBC)/divinylbenzene (DVB) copolymers via surfactant-free emulsion polymerization yields near monodisperse chloromethylated polystyrene precursor nanospheres similar to 400 nm in diameter. These are analogous to gel-type suspension polymerized particles typically of similar to 100-500 Am in diameter and are essentially nonporous in the dry state having only a very nominal surface area (similar to 10 m(2) g(-1)). Cross-linking of appropriate dichloroethane swollen precursors with a high content of VBC residues in the presence of FeCl3 (i. e., using a Davankov-type strategy) yields near monodisperse porous hyper-cross-linked nanoparticles with extremely high surface areas up to similar to 1200 m(2) g(-1). The latter display all the characteristics of Davakov-type resins in terms of their ability to sorb both thermodynamically "poor" and "good" solvents and in particular despite their superficial hydrophobic makeup are able to sorb significant quantities of water (up to similar to 2.5 g/g). By adjusting the content of VBC in the precursor particles, the surface area of the near monodisperse nanoparticles can be adjusted in the range similar to 15-1300 m(2) g(-1).