Tailored hierarchically structured (organo) silica beads with particle diameters between 0.3 and 2.5 mm have been prepared using an emulsion based sol-gel approach. Poly(propylene oxide)-poly(ethylene oxide) triblock copolymers as surfactants, aniline or 1-butanol as solvent and different silanes such as tetraethyl silicate, [3-(2-aminoethylamino)propyl]trimethoxysilane and phenyltrimethoxysilane are used to direct morphology and porosity. The silica spheres provide specific surface areas up to 900 m(2)/g and adjustable porosity in the meso- and macroporous region. The texture includes particulate structures with controllable size between 80 nm and 2.5 mu m of the silica particles on the inside of the spheres and a macroporous foam-like shell with macropores in the range between 0.2 and 4.0 mu m and a thickness of the shell between 0.6 and 44 mu m. The high variability of this preparation method and the simultaneous control of the nano-to millimeter scale structure including the porosity as well as the morphology allows one to design tailor-made adsorbents and catalysts.     «

Tailored hierarchically structured (organo) silica beads with particle diameters between 0.3 and 2.5 mm have been prepared using an emulsion based sol-gel approach. Poly(propylene oxide)-poly(ethylene oxide) triblock copolymers as surfactants, aniline or 1-butanol as solvent and different silanes such as tetraethyl silicate, [3-(2-aminoethylamino)propyl]trimethoxysilane and phenyltrimethoxysilane are used to direct morphology and porosity. The silica spheres provide specific surface areas up to...     »

ISI Document Delivery No.: 751AF Times Cited: 1 Cited Reference Count: 22 Scholz, Sabine Lercher, Johannes A. Wacker Chemie AG Financial support by Wacker Chemie AG and fruitful discussions within the Wacker-Institut fur Siliciumchemie and the framework of the network of excellence IDECAT is gratefully acknowledged. The authors thank Wacker Chemie AG and the BASF Corporation for the gift of the Geniosil silanes, TES40, and the Pluronic polymers, Dipl.-Ing. Martin Neukamm for SEM analysis, Dipl.-Ing. Xaver Hecht for BET analysis and Hg-porosimetry, Georgeta Krutsch and Aleksandra Jonovic for TGA measurements, Ulrike Ammari and co-workers from the microanalytical lab for elementary analysis, and Dr. Yongzhong Zhu for helpful discussions. 1 Amer chemical soc Washington     «

ISI Document Delivery No.: 751AF Times Cited: 1 Cited Reference Count: 22 Scholz, Sabine Lercher, Johannes A. Wacker Chemie AG Financial support by Wacker Chemie AG and fruitful discussions within the Wacker-Institut fur Siliciumchemie and the framework of the network of excellence IDECAT is gratefully acknowledged. The authors thank Wacker Chemie AG and the BASF Corporation for the gift of the Geniosil silanes, TES40, and the Pluronic polymers, Dipl.-Ing. Martin Neukamm for SEM analysis, Dipl.-...     »