in this paper, 4,4ʹ-bipyridinium dichloride  supported sba-15 (sba@bipy2+ 2cl-) was used for the synthesis of dihydropyrimidinones. the synthesized catalyst was characterized by ft-ir spectroscopy, scanning electron microscopy (sem), transmission electron microscopy (tem) and thermogravimetric analysis (tga). this nanocomposite was shown to be an efficient heterogeneous catalyst for the synthes...

Mesoporous silica has been used as a heterogeneous support for catalysts; however, asymmetric induction by the helicity of inorganic mesoporous silica itself has not yet been achieved. P- and M-helical mesoporous silica was found to act as a chiral inorganic trigger for asymmetric autocatalysis to afford (S) and (R)-pyrimidyl alkanol with >99.5% ee, respectively.

Silica monolithic columns suitable for implementation on microchips have been evaluated by ion-exchange capillary electrochromatography. Two different silica monoliths were created from the alkyl silane, tetramethyl orthosilicate (TMOS), by introducing a water-soluble organic polymer, poly(ethylene oxide) (PEO), with varying molecular weights into the prehydrolyzed sol. Silica monoliths created...

Highly uniform 3-D ordered macroporous spheres in regular arrays were produced by a double templating process. The first template of larger silica balls produced the polymer skeleton for guiding the shape and size of the self-assembled superstructure of smaller polymeric balls, which are introduced subsequently into the internal space of the skeleton. The second templating with inorganic precur...

The association of natural polymers with silica is a fruitful strategy to design novel hybrid structures with potential applications in the fields of biotechnology, medicine, and environmental sciences. Here we illustrate the principles of formation, the structure, and the properties of such biohybrid systems by the specific example of silica–pectin porous materials. The influence of the silica...

PSU/MMT nanocomposites are prepared by dispersing MMT nanolayers in a PSUmatrix via in situ photoinduced crosslinking polymerization. Intercalated methacrylate-functionalized MMT and polysulfone dimethacrylate macromonomer are synthesized independently by esterification. In situ photoinduced crosslinking of the intercalated monomer and the PSU macromonomer in the silicate layers leads to nanoco...

2.4. Sol-Gel Reactions 2070 2.5. Polyol Methods 2071 2.6. Flow Injection Syntheses 2071 2.7. Electrochemical Methods 2071 2.8. Aerosol/Vapor Methods 2071 2.9. Sonolysis 2072 3. Stabilization of Magnetic Particles 2072 3.1. Monomeric Stabilizers 2072 3.1.1. Carboxylates 2073 3.1.2. Phosphates 2073 3.2. Inorganic Materials 2073 3.2.1. Silica 2073 3.2.2. Gold 2074 3.3. Polymer Stabilizers 2074 3.3...

We have established a facile and generalizable "silica-assisted" synthesis for diverse carbon spheres-a category that covers mesoporous carbon nanospheres, hollow mesoporous carbon nanospheres, and yolk-shell mesoporous carbon nanospheres-by using phenolic resols as a polymer precursor, silicate oligomers as an inorganic precursor, and hexadecyl trimethylammoniumchloride as a template. The part...

Polyethylene (PE) and silica are perhaps the simplest and most common organic and inorganic polymers, respectively. We describe, for the first time, a physically interpenetrating nanocomposite between these two elementary polymers. While polymer-silica composites are well known, the nanometric physical blending of PE and silica has remained a challenge. A method for the preparation of such mate...

Free-radical polymerization inside mesoporous silica has been investigated in order to open a route to functional polymer-silica composite materials with well-defined mesoporosity. Various vinyl monomers, such as styrene, chloromethyl styrene, 2-hydroxyethyl methacrylate, and methacrylic acid, were polymerized after impregnation into mesoporous silicas with various structures, which were synthe...