Method for preparing silica aerogel material

Abstract

The invention discloses a method for preparing a silica aerogel material and relates to the method for preparing the aerogel material, in particular to the method for rapidly preparing a transparent SiO2 aerogel by being based on the sol-gel technology and adopting secondary modification and normal pressure drying. The invention provides the method for preparing the silica aerogel material, and the method has simple technology, short cycle, low cost and good safety and is conductive to large-scale production. Tetraethoxysilane is adopted as a silicon source, methyl trimethoxysilane or methyl triethoxysilane is taken as a modifier of a co-precursor, anhydrous ethanol is taken as a solvent, and hydrochloric acid and ammonia are taken as catalysts. The sol-gel acid-base two-step method is adopted for catalysis, thereby preparing the SiO2 wet gel; and the further modification is carried out on a wet gel sample after aging treatment under certain conditions, and the normal pressure low-temperature drying is finally carried out in air atmosphere, thereby preparing the SiO2 aerogel. The equipment cost during the preparation technology is low, the product has good performances and the reaction process is controllable.

Description

technical field [0001] The invention relates to a preparation method of an airgel material, in particular to a method based on sol-gel technology and adopting secondary modified atmospheric pressure drying to rapidly prepare transparent SiO 2 Airgel method. Background technique [0002] Airgel is the lightest solid known in the world, and it is included in the Guinness Book of World Records. Airgel is mainly divided into inorganic oxide aerogel, organic aerogel and carbon gas obtained by carbonization of organic aerogel. gel. Silicon dioxide (SiO 2 ) airgel was first prepared by Kistler of Stanford University in 1931 through sol-gel method and supercritical drying technology. [0003] SiO 2 Airgel is a kind of material with high specific surface area (500~1500m 2 / g), high porosity (80%~99.8%), low density (~0.03g / cm 3 ), low refractive index (1~1.1), low thermal conductivity (~0.01W·m -1 ·K -1 ), low dielectric constant (1.0-2.0) and other nano-porous solid material...

AI Technical Summary

Problems solved by technology

[0016] Compared with the supercritical drying process, the preparation of SiO by atmospheric pressure drying 2 Airgel greatly reduces the cost and operational risk, the equipment used is simple and can be produced continuously, and the SiO 2 The possibility of industrial production of airgel, but some normal pressure drying methods have a long preparation period, and the preparation process route needs to be optimized

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