Study On Synthesis And Application Of Functional Inorganic/Organic Composite Particles

The surface modification of ultrafine silica was investigated and many functional inorganic/organic composite particles were synthesized by physical and chemical methods in this paper. Because these composite particles have a lot of excellent behavior such as hydrophobic, anti-bacteria, light stability and ability to disperse in organic medium, the use sphere of superfine silica were broadened and new products with high value were developed in this works.Functions are realized on the surface of ultrafine silica in the inorganic/organic composite systems. According to the different functions expected, wet method or dry method is selected to modify the silica particles, and special organic component with functional group is also coated on the surface of silica particles relying on the formation of physical adsorption or chemical bond. The functional inorganic/organic composite particles have core-shell structure after the drying process in the preparation. The surface properties of the composite particles are improved greatly when using nanosilica as starting materials.The surface of hydrophilic silica was coated by organic component using wetting method or spray method, and chemical bond was engendered by the reaction of stearic acid or stearic alcohol with the silica modified by silane coupling agent with propriety reactive group. The resulting hydrophobic organic coating on silica not to fall off in use and processing, and the excellent hydrophobic inorganic/organic composite particles were prepared successfully.A tertiary amine salt having ester group was produced by the reaction of 1,2,2,6,6-pentamethyl-4-piperidinol and anhydride in toluene, and the light stability composite particles having hindered amine structure were obtained by the amine salt reacted with the silica particles by liquid/solid two-phase interface reaction method or W/O emulsion method in a mixture solvent of toluene and ethanol, and then by azeotropic distillatioion and vacuum drying at 130℃.Anti-bacteria DCDMH or DBDMH was directly synthesized in an aqueous suspension of silica, and they were absorbed on the surface of silica particles by physical or chemical effect, then the inorganic carrier was coated with special anti-bacteria organic matter, anti-bacteria inorganic/organic composite particles with...