Well ordered mesoporous silica films were prepared by infusion and selective condensation of Si alkoxides within pre-organized block copolymer/homopolymer blend templates using supercritical CO2 as the delivery medium. The morphologies of mesoporous silica films reflect improvements in the long range order of poly (ethylene oxide-b-propylene oxide-b-ethylene oxide) triblock copolymer film templates imparted by blending with selectively associating homopolymers such as poly (acrylic acid) or poly (4- hydroxystyrene) prior to alkoxide infusion. Control over film porosity, pore ordering, and morphology of mesoporous silica films is achieved through simple variations in the homopolymer concentration. The films were characterized using x-ray reflectivity, small angle x-ray scattering and transmission electron microscopy.
Citation: Chemistry of Materials
Pub Type: Journals
block copolymers, homopolymers, long-range order, mesoporous silica, nanotechnology, supercritical carbon dioxide