Preparation method of surface-hybridized high-strength silicon dioxide microspheres

Abstract

The invention discloses a preparation method of surface-hybridized high-strength silicon dioxide microspheres, and relates to preparation of micron-sized inorganic / organic hybridized silicon dioxide microspheres. The preparation method comprises the following steps: by taking high-purity inorganic silicon dioxide microspheres subjected to high-temperature calcination as matrix microspheres, removing moisture in the microspheres, enabling the microspheres to obtain the characteristic of high mechanical strength, then mixing the microspheres with a proper amount of anhydrous toluene, heating and refluxing, adding an alkaline compound as a catalyst, then dropwise adding a toluene solution of tetraethoxysilane and alkoxy silane containing organic functional groups, and reacting for 2-4 hours at the temperature of 60-80 DEG C; the two silanization reagents are subjected to condensation polymerization on the surfaces of the silicon dioxide microspheres and the surfaces of the pore channels to form a hybrid layer, the microspheres are separated from a solution after the reaction is finished, the microspheres are cleaned, and vacuum drying is performed to obtain the product. The hybrid microsphere not only has high mechanical strength of an inorganic silicon dioxide microsphere, but also has stable chemical performance of an inorganic / organic hybrid silicon dioxide microsphere. And the method can be applied to wider pH separation conditions.

Description

technical field [0001] The invention relates to the preparation of micron-scale inorganic / organic hybrid silica microspheres, in particular to a preparation method of surface hybrid high-strength silica microspheres. Background technique [0002] Porous silica microspheres have been widely used in chromatographic analysis, but the chemical properties of silica gel itself still limit its application range. First, its chemical stability is poor, unstable in alkaline mobile phase, and can only be used in the range of pH=2-8. Another disadvantage of long-term use is that there are a large number of active silanol groups on the surface of silica gel, which interferes with the separation of alkaline substances. The emergence of hybrid matrix silica gel makes silica gel perfectly solve the above shortcomings. Hybrid silica gel is made by incorporating organic groups into the molecular skeleton to make the material show more excellent chemical stability, but the organic groups in th...

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Problems solved by technology

[0002] Porous silica microspheres have been widely used in chromatographic analysis, but the chemical properties of silica gel itself still limit its application range. First, its chemical stability is poor, unstable in alkaline mobile phase, and can only be used in the range of pH=2-8. Another disadvantage of long-term use is that there are a large number of active silanol groups on the surface of silica gel, which interferes with the separation of alkaline substances.

The emergence of hybrid matrix silica gel makes silica gel perfectly solve the above shortcomings. Hybrid silica gel is made by incorporating organic groups in the molecular skeleton to make the material show more excellent chemical stability, but the organic groups in the skeleton are at high temperature (approximately 300°C) is easy to decompose and burn, so that silica gel cannot obtain higher mechanical strength through calcination (greater than 400°C), so hybrid silica gel loses the advantages of high mechanical strength when it obtains excellent chemical stability

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