Organically modified silica functions

There are four major functions of amino groups attached to organically modified silica gels ... 

Summary Mixed functionalized octa( -alkyl/halogenalkylsilsesquioxanes) with different side chains has been prepared by acid-catalyzed cohydrolysis of w-alkyl- and lialogenalkyltrichlorosilanes. The silsesquioxane mixtures were separated in preparative amounts with normal-phase HPLC. Mixed functionalized octa( -alkyl/halogenalkylsil-sesquioxanes) with different side chains are suitable examples of an organically modified silica gel. They can be modified by nucleophilic substitution of the halogen atom with -PPh and rhodium-phosphino complexes are be formed. 

In recent years, silica sol-gel-based inorganic-organic hybrid materials have also been reported. The introduction of various functional groups into organic alkoxide has led to organically modified sol-gel glasses (ormosils). Some of the ormosil monomers and ormosil formations can be found in Fig. 16.3. Redox molecules can be coupled with the ormosil monomer functional group. The immobilized redox molecules can... 

The ability of organically modified ceramics based on alumina, zirconia, titania, or silica (and mixtures of each) to function as abrasion-resistant coatings has also been studied (62). For example, polycarbonate, when coated with an epoxy—aluminosilicate system, experiences a significant reduction in the degree of hazing induced by an abrader, as compared to uncoated polycarbonate. 

Markowitz et al. developed a different approach, again in an attempt to overcome some of the inherent difficulties that arise when imprinted bulk materials are used as catalysts [82], Here, the authors used a template-directed method to imprint an a-chymotrypsin TSA at the surface of silica nanoparticles, prepared with a number of organically modified silanes as functional monomers. Silica particle formation was performed in a microemulsion, where a mixture of a non-ionic surfactant and... 

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