Method for preparing high-dispersity nanosilicon dioxide particle

Abstract

The invention relates to a method for preparing high-dispersity nanosilicon dioxide particles. The method comprises the following steps: firstly, modifying nanosilicon dioxide particles to graft an azide group on the surfaces of the nanosilicon dioxide particles, preparing a polymer with a plurality of alkynyl groups on a non-terminal group of the molecular chain in a free radial polymerization mode, and finally the surfaces of the particles with the polymer through click chemistry reaction. The modified nanosilicon dioxide particles prepared by using the method are good in dispersity in organic solvents, overcome the problem of easy conglobation and have great application potential in the fields of coatings, composite materials and the like.

Description

technical field [0001] The invention particularly relates to a preparation method of highly dispersed nano silicon dioxide particles, belonging to the technical fields of polymer chemistry and organic materials. Background technique [0002] Nano-silica is widely used in coatings, chemical industry, composite materials, environmental protection, food, construction and other fields. However, nano-silica has small particles, large specific surface area, strong interaction between particles, and is easy to agglomerate and difficult to disperse. , the defects exposed during the application process lead to the degradation of the overall material performance, limiting its wide application. [0003] In order to improve its dispersibility, many methods have been developed, such as patent CN 103922352 A introducing the use of polyhydric alcohols to improve its dispersibility under alkaline conditions; patent CN 103097467 A introducing the use of 1,4-butanediol and monoethylene glycol...

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Problems solved by technology

[0002] Nano-silica is widely used in coatings, chemical industry, composite materials, environmental protection, food, construction and other fields, but the particles of nano-silica are small and the specific surface area Large, strong interaction between particles, easy to agglomerate, not easy to disperse, and the defects exposed during the application process lead to the decline of the entire material performance, which limits its wide application

[0003] In order to improve its dispersibility, a variety of methods have been developed, such as the introduction of patent CN 103922352 A to improve its dispersibility under alkaline conditions by utilizing polyols; patent CN 103097467 A introduces the use of 1,4-butanediol and monoethylene glycol to enhance its dispersibility as a chain extender; in the patent CN 102816458 A, nano silicon dioxide or its modified products are dispersed in organosilane to form a dispersion; there are A large number of literatures have reported that polymers compatible with the substrate are grafted on the surface through chemical reactions. The grafted reactive groups are all at one end of the molecular chain or compound, which will lead to the generation of grafted molecular chains. The steric hindrance effect affects the dense coating of other molecular chains on the surface of silica, resulting in poor dispersion of silica particles, or a large amount of polymer must be grafted to achieve the dispersion effect

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