title: Robust ordered cubic mesostructured polymer/silica composite films grown at the air/water interface.
abstract: Polymer/silica composite films, stable to calcination, were produced using catanionic surfactant mixtures (hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS)) and polymers (polyethylenimine (PEI) or polyacrylamide (PAAm)) at the air/water interface. Film formation processes were probed by time-resolved neutron reflectivity measurements. Grazing incidence X-ray diffraction (GID) measurements indicate that the mesophase geometry of the interfacial films could be controlled to give lamellar, 2D hexagonal, and several cubic phases (Pn3¯m, Fm3¯m, and Im3¯m) by varying the polyelectrolyte molecular weight, polyelectrolyte chemical nature, or the cationic:anionic surfactant molar ratio. On the basis of GID results, a phase diagram for the catanionic surfactant/polyelectrolyte/TMOS film system was drawn. These films can be easily removed from the interface and mesoporous silica films which retain the film geometry can be obtained after calcination; moreover, this film preparation method provides a simple way to impart polymer functionality into the mesostructured silica wall, which means these films have potential applications in a variety of fields such as catalysis, molecular separation, and drug delivery.
authors: Department of Chemistry, University of Bath, Claverton Down, Bath, United Kingdom.
authors: Bin
authors: B
authors: Yang
authors: James A
authors: JA
authors: Holdaway
authors: Karen J
authors: KJ
authors: Edler