Preparation And Application Of The Azide Organic-inorganic Hybrid Silica Material

Mesoporous silica is of wide application in areas such as adsorption, chromatography, catalysis, etc. The surface modification is a key step for the silca to get functionalized, and for most of the time, it involves reaction on solid phase which requires for high selectivity and high efficiency, and click chemistry can be welled suited for that requirements.This thesis is focused on providing a kind of azide organic-inorganic hybrid silica material with which the surface functionizaiton process can be achieved by click chemisty, and the availability of its surface reaction has been preliminary investigated.With a modified Stober method, the azide organic-inorganic hybrid silica spheres have been synthesized through one-pot co-condensation of 3-azidopropyltriethoxysilane (AzPTES) and tetraethylorthosilicate (TEOS) by utilizing a kind of cationic triblock-polymer surfactant. The influence of the temperature, surfactant content, solvent have been systematicly investigated. Spheres of good monodisperisty and uniformity can be obtained by adjusting the methonal/water ratio and surfactant concerntraton in certain range. The pore size can be adjusted between 71 A-176 A simply by changing the aging temperature, and the large pore size is beneficial for the introduction of the organic compounds especially those with large molecular weight into the inorganic materials, and by varing the AzPTES/TEOS ratio, the density of the azide group can be adjusted which provide a method for the controlled loading of the organic compounds. Meantime, the effect of the co-surfactant cetyltrimethylammonium bromide (CTAB) to the sphere's pore diameter, suface area and morphology have also been studied.On the basis of the materials preparation, several alkynylcompounds have been anchored onto the silica through click chemistry resulting with CBS immobilized catalyst, tartaric acid type chiral stationary phase, C8 and NH3 stationary phase. CBS immobilized catalyst shows certain asymmetric catalytic ability in the reduction of the acetophenone. The tartaric acid type chiral stationary phase has certain chiral separiton ability for some dinaphthol derivatives. The C8 and NH2 stationary phase retains its hydrophobic hydrophilic properties, respectively, and meantime, both obtain the ion exchange property provided by the triazole ring introduced during the click chemistry process.