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Telechelic Polyethers by Living Polymerizations and Precise Macromolecular Engineering
Published in Sophie M. Guillaume, Handbook of Telechelic Polyesters, Polycarbonates, and Polyethers, 2017
Pierre J. Lutz, Bruno Ameduri, Frédéric Peruch
In recent years, considerable research efforts have been devoted to nanostructured silicates and silicate nanoparticles as well as to mesoporous silicate structures with uniform pore channels, based on self-assembled organic template molecules. Among these organosubstituted spherosilsesquioxanes, (RSiO3/2)n represent interesting and unique 3D nanometer-sized building units for the construction of organic-inorganic hybrid structures. They have already been used to create a large variety of hybrid macromolecular architectures [158,159–160]. Typically, well-defined polyoctahedral silsesquioxanes (POSSs) with the composition R8Si8O12 or R1R7Si8O12 have been successfully incorporated either by grafting or by copolymerization in polymeric materials [161]. Such POSS structures have a high potential, once combined with PEO, to provide water-soluble biocompatible organic-inorganic hybrid materials. In the case of PEO, depending on the number of PEO, the protection of the core exerted by the PEO chains may be more or less efficient. Selected relevant examples of the grafting of mono- or bifunctional telechelic PEOs onto octameric cyclic POSS structures characterized by the formula H8SiO8O12 (T8H) for octahydridosilsesquioxane or (HSiMe2O)8O12 (Q8M8H) for octakis(hydridodimethylsiloxy) octasilsesquioxane are presented and discussed thereafter.
Mesoporous Silica and Its Prospects for Humidity Sensor Application
Published in Ghenadii Korotcenkov, Handbook of Humidity Measurement, 2020
A mesoporous silica can also be employed as a hard template for the synthesis of a mesoporous material of a composition valuable for humidity sensing (Melde et al. 2008). Ordered, well-defined mesostructures are particularly suited to these applications. In particular, mesoporous silicates have been used to template carbons, metals, and metal oxides. The silicate framework is usually removed following templating by dissolving with hydrofluoric acid or a strong base.
Removal of antibiotics from aqueous solution using silicon-based materials. An overview
Published in Environmental Technology Reviews, 2018
Yige Guo, Bin Chen, Dongfang Liu, Wenli Huang, Yu Sun, Ying Zhao
Since the discovery of M41S family by Mobil workers in 1992, highly ordered mesoporous silicate materials with high surface area, large pore volume and large pore size have received widespread attention. Up to now, varieties of highly ordered mesoporous silica materials such as M41S, SBA,3,4,15, HMS,8,9 and KIT,10 etc. have been successfully synthesized. These materials are mainly synthesized by a liquid–crystal mechanism (Figure 5) and their structures can be formed from molecular aggregates of surfactants [72]. The most commonly used meso-porous silicon we discussed in this review is composed by MCM meso-porous materials and SBA meso-porous materials.
An efficient synthesis of highly substituted functionalized pyrroles via a four-component coupling reaction catalyzed by Fe(III)-Schiff base/SBA-15
Published in Inorganic and Nano-Metal Chemistry, 2020
Ghasem Rezanejade Bardajee, Aseyeh Ghaedi, Hamideh Hazrati, Farnaz Jafarpour
Mesoporous silicate-aluminosilicates are Santa Barbara Amorphous (SBA) materials characterized by uniform pore size (4.6–30 nm), well-defined pore structure and size-distribution, high surface area, high thermal stability and the capability to support a large panel of active species including Lewis acid metal ions. One of the most promising components of this family is SBA-15.[12]