Microporous Mesoporous Mat.

Highly ordered periodic mesoporous organosilicas (PMOs) with the 1,4-diureylenebenzene moieties incorporated into the silica framework walls were synthesized through co-condensation of bissilylated 1,4-diureylenebenzene and tetraethyl orthosilicate using triblock copolymer P123 as a structure-directing agent in acidic solutions. These PMOs were characterized by powder X-ray diffraction, N(2) adsorption/desorption measurements, (13)C and (29)Si solid state NMR spectra, FT-IR, SEM, TEM and elemental analysis. It is observed that the PMOs containing 1,4-diureylenebenzene groups inside the pore walls possess large surface area ranging from 423 to 223 m(2)/g and uniform mesopores between 4.7 and 6.2 nm. With the increasing component of the bissilylated precursor to 10 mol%, PMOs with a rod-like morphology were obtained. When the fraction of the bridged organosilane exceeds 10 mol% in the start mixture, the orderness of the PMOs decreases and the mesoporous wall structure collapses under the adopted synthetic conditions. (C) 2007 Elsevier Inc. All rights reserved.Highly ordered periodic mesoporous organosilicas (PMOs) with the 1,4-diureylenebenzene moieties incorporated into the silica framework walls were synthesized through co-condensation of bissilylated 1,4-diureylenebenzene and tetraethyl orthosilicate using triblock copolymer P123 as a structure-directing agent in acidic solutions. These PMOs were characterized by powder X-ray diffraction, N(2) adsorption/desorption measurements, (13)C and (29)Si solid state NMR spectra, FT-IR, SEM, TEM and elemental analysis. It is observed that the PMOs containing 1,4-diureylenebenzene groups inside the pore walls possess large surface area ranging from 423 to 223 m(2)/g and uniform mesopores between 4.7 and 6.2 nm. With the increasing component of the bissilylated precursor to 10 mol%, PMOs with a rod-like morphology were obtained. When the fraction of the bridged organosilane exceeds 10 mol% in the start mixture, the orderness of the PMOs decreases and the mesoporous wall structure collapses under the adopted synthetic conditions. (C) 2007 Elsevier Inc. All rights reserved