A method for preparing airgel fiber mat by secondary compounding

Abstract

The invention provides a method for preparing an airgel fiber mat through secondary compounding. First, the surface treatment agent of the fiber mat is removed by heat treatment, and then the surface is hydrophobically modified by using a silane coupling agent; the above pretreated fiber mat is Except for one side, the other sides are encapsulated, and the airgel slurry cannot enter and exit the inner aperture of the fiber mat through the side of the package; the airgel slurry made of airgel powder is filled into the packaged surface by vacuum infusion. In the fiber mat, the unencapsulated surface of the fiber mat is finally encapsulated so that the airgel slurry cannot pass into and out of the inner pores of the fiber mat. The preparation process of the method of the present application is relatively simple, does not require expensive production equipment, and the cost is low, and the performance of the prepared airgel fiber mat can be comparable to the in-situ synthesis method; to ensure that the airgel particles are fully filled inside the fiber mat , the surrounding resin encapsulation can prevent the airgel powder from falling off, and the obtained airgel fiber mat has excellent performance.

Description

technical field [0001] The invention belongs to the technical field of airgel functional materials, and in particular relates to a method for preparing an airgel fiber mat through secondary compounding. Background technique [0002] Aerogel has the characteristics of extremely low density, high specific surface area, and high porosity. It is considered to be the best porous material for thermal insulation. However, the low strength of pure aerogel limits its application. Therefore, fiber-reinforced materials are usually used to strengthen aerogels to form airgel fiber mats to overcome the problem of poor aerogel strength and meet the requirements of use. [0003] At present, airgel fiber mat products mainly adopt the method of in-situ compounding. For example, in the preparation process of airgel fiber mat disclosed in patent CN105906298A, the airgel precursor needs to go through sol-gel reaction, solution graded replacement, surface Complex steps such as modification, atmo...

AI Technical Summary

Problems solved by technology

[0003] At present, airgel fiber mat products mainly adopt the method of in-situ compounding. For example, in the preparation process of airgel fiber mat disclosed in patent CN105906298A, the airgel precursor needs to go through sol-gel reaction, solution graded replacement, surface Complex steps such as modification, atmospheric pressure drying or supercritical drying generate airgel in situ inside the fiber mat, which has the disadvantages of complex process, long cycle and high cost.

In order to overcome the defects of the in-situ synthesis method, people try to prepare airgel fiber mats by secondary compounding (such as CN 107604634 A, CN 106757781A, CN 107574657 A and other patents). In the preparation method, airgel powder solutions with different particle sizes and fiber mats are mainly compounded by direct soaking, spraying, coating, etc. to obtain airgel fiber mats. These methods have simple processes and require simple equipment. It greatly reduces the production cost, and it is difficult to ensure that the airgel particles are completely filled inside the fiber mat, especially when the fiber mat is thicker, it is more difficult to fill and compound, so it is only suitable for the production of airgel ultra-thin fiber mat