Glass fiber aerogel heat insulation felt and preparation method thereof

Abstract

The preparation method comprises the following steps: firstly, mixing a silicon source, ethanol, deionized water and a catalyst according to a certain proportion to prepare a silicon dioxide glue solution, then immersing one or more layers of glass fiber base materials into the prepared silicon dioxide glue solution, carrying out circulating reflux, pressing, aging the gel, and carrying out vacuum drying to obtain the glass fiber aerogel heat insulation felt. And after modification, drying to obtain the glass fiber aerogel heat insulation felt. The glue solution in the tank body is circulated by using the pump machine, so that the glass fiber base material is immersed in the glue solution, meanwhile, bubbles enriched on the outer layer of the base material are expelled by using the pressing block or the rolling shaft, and the finally obtained glass fiber aerogel heat insulation felt product is free of glue shortage in appearance. The technological process is finely designed, the adjustable characteristic suitable for preparation of various reinforced fibers is shown, meanwhile, the characteristics of being low in technological production cost and easy to operate are achieved, and the performance of all regions of the produced aerogel felt can be promoted to be unified, so that the performance is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of aerogel composite materials technology, and in particular to a glass fiber aerogel thermal insulation felt and its preparation method. Background Technology

[0002] When glass fiber mat is combined with aerogel, the excellent properties of both are combined to form a high-performance, multifunctional composite material. Compared with traditional thermal insulation materials, it has advantages in important properties such as thermal insulation performance, unit mass, corrosion resistance, and structural stability. Therefore, this aerogel composite material is widely used in building energy conservation, new energy storage, new energy vehicles, chemical industry and other fields. As a result, aerogel glass fiber mat has a wide range of applications and a huge demand.

[0003] In actual large-scale production, when using the sol-gel method to prepare roll aerogel composites, the dense internal structure of the glass fiber mat roll prevents the adhesive from fully penetrating during the immersion process. This hinders the removal of air bubbles from the roll, resulting in areas of insufficient adhesive at the time of finished product discharge, leading to material waste and reduced yield. Therefore, improving the adhesive-free conditions based on existing procedures is crucial. Summary of the Invention

[0004] The purpose of this invention is to provide a glass fiber aerogel thermal insulation felt and its preparation method, thereby improving the problem of uneven impregnation of adhesive solution during the preparation of glass fiber aerogel thermal insulation felt.

[0005] To solve the above-mentioned technical problems, the present invention provides a method for preparing glass fiber aerogel thermal insulation felt, comprising the following steps: Step A: Mix the silicon source, ethanol, deionized water and catalyst in a certain proportion to prepare a silica gel solution; Step B: Immerse one or more layers of glass fiber substrate in the prepared silica gel solution, circulate and recirculate, press and age the gel, and dry after modification to obtain glass fiber aerogel insulation felt.

[0006] Preferably, the silicon source in step A is tetraethyl orthosilicate, tetraethyl orthosilicate 40 or tetraethyl orthosilicate 28, the catalyst is ammonia and ammonium fluoride, and the ethanol content is 60.0-99.99%.

[0007] Preferably, the proportions of the components in the silica gel solution prepared in step A are as follows: the mass ratio of silicon source: ethanol: deionized water: ammonia: ammonium fluoride is 100: 50-1000: 0-30: 0-10: 0-10.

[0008] Preferably, the glass fiber substrate in step B includes silicon dioxide, magnesium oxide, aluminum oxide, calcium oxide, boron oxide, and titanium oxide; its thickness is 0.1-100 mm.

[0009] Preferably, the reflux in step B is achieved by using a pump to reflux the silica liquid in the tank repeatedly to ensure that the glass fiber substrate is fully impregnated with the silica, and the time is >5 minutes.

[0010] Preferably, the pressing in step B is done by using a rubber block to apply pressure in the range of 5KG-10KG, pressing from one end of the glass fiber substrate to the other end, with each pressing interval being 3-5cm, and the number of pressing times being 2-3.

[0011] Preferably, the aging time in step B is 16-72 hours.

[0012] Preferably, in step B, the multilayer glass fiber substrates are separated by one or more of nonwoven fabric, monofilament filter cloth, spunlace cloth, fiber cloth, fiber paper, and polyethylene, polypropylene, polyester, polyamide mesh or membrane, and are slowly placed in the modification liquid.

[0013] Preferably, the drying time in step B is 4-72 hours, and the drying method is any one of supercritical drying, freeze drying, vacuum drying, or room temperature and pressure drying.

[0014] The present invention also provides a glass fiber aerogel thermal insulation felt. The glass fiber aerogel thermal insulation felt prepared by the above-mentioned method has a thermal conductivity of ≤0.023W / (m·K) at 25℃ and a compression of 60.4% at 2MPa. Compared with the traditional method, it can effectively improve the uniformity of adhesive impregnation into the fiber felt while meeting the relevant mechanical performance parameter requirements and with lower operation difficulty.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. The preparation method of the glass fiber aerogel thermal insulation felt of the present invention promotes the fullness of the glass fiber substrate in the composite with silica gel liquid during the dynamic stage of the pressing operation. Furthermore, the glass fiber aerogel thermal insulation felt prepared by the method of the present invention exhibits significantly reduced glue deficiency and a good appearance; and it can be adapted to the production needs of glass fiber aerogel thermal insulation felts of different specifications. 2. By adjusting the pressure distribution and pressing sequence in real time, the flow path of the silica gel liquid in the glass fiber substrate is optimized to achieve a uniform impregnation effect. This invention utilizes a pump to circulate the silica gel in the tank, immersing the glass fiber substrate in the liquid. Simultaneously, pressure blocks or rollers are used to expel air bubbles accumulated on the outer layer of the substrate, resulting in a glass fiber aerogel insulation felt product with no missing adhesive. The process flow of this invention is meticulously designed, exhibiting adjustable characteristics suitable for the preparation of various reinforcing fibers. It also features low production costs and simple operation, promoting uniform performance across all areas of the produced aerogel felt, resulting in significant performance improvements. Detailed Implementation

[0016] The features, operations, and characteristics described in this specification can be combined in any suitable manner to form various embodiments. Similarly, the steps or actions described in the method can be rearranged in a manner readily apparent to those skilled in the art. Therefore, the various orders in this specification are merely for the purpose of clearly describing a particular embodiment and are not necessarily required orders, unless otherwise stated that a particular order must be followed.

[0017] Example 1 This invention provides a method for preparing glass fiber aerogel insulation felt. First, 84.5 kg of ethyl silicate and 189.1 kg of ethanol are mixed. Then, 15.1 kg of deionized water is slowly added under stirring. Next, 1.09 kg of ammonia and 0.51 kg of ammonium fluoride are added slowly in sequence, and the mixture is stirred for 7 minutes to obtain silica sol.

[0018] Then, a roll of 0.7 mm thick glass fiber substrate was slowly immersed in the aforementioned silica sol, and pressed into the sol with a cover plate. Next, a pump was used to circulate the silica sol back and forth to ensure complete impregnation of the glass fiber substrate for 40 minutes. Simultaneously, a rubber press was used to apply pressure of 5-10 kg from one end of the glass fiber substrate to the other, with each press interval of 3-5 cm, and the number of presses was 2-3 times. Finally, after gelling and aging at room temperature for 12 hours, it was placed in a modification tank for 30 hours, then removed and transferred to a supercritical drying oven for 6 hours to obtain glass fiber aerogel insulation felt. The glass fiber aerogel insulation felt prepared by this method has a thermal conductivity of ≤0.023 W / (m·K) at 25℃ and a compression loss of 60.4% at 2 MPa.

[0019] Example 2 The present invention also provides a method for preparing glass fiber aerogel insulation felt. First, 84.5 kg of ethyl silicate and 189.1 kg of ethanol are mixed, and then 15.1 kg of deionized water is slowly added under stirring. Next, 1.09 kg of ammonia and 0.51 kg of ammonium fluoride are added slowly in sequence, and the mixture is stirred for 7 min to obtain silica sol.

[0020] Then, a roll of 1.0 mm thick glass fiber substrate is slowly immersed in the aforementioned silica sol, and pressed into the sol with a cover plate. Next, the silica sol is circulated back and forth using a pump to ensure complete impregnation of the glass fiber substrate for 45 minutes. Simultaneously, a rubber press is used to apply pressure of 5-10 kg from one end of the glass fiber substrate to the other, with each press interval of 3-5 cm, and the number of presses is 2-3 times. Finally, after gelling and aging at room temperature for 20 hours, it is placed in a modification tank for 36 hours, then removed and transferred to a supercritical drying oven for 8 hours to obtain glass fiber aerogel insulation felt. The glass fiber aerogel insulation felt prepared by this method has a thermal conductivity of ≤0.023 W / (m·K) at 25℃ and a compression loss of 60.4% at 2 MPa.

[0021] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A method for preparing a glass fiber aerogel thermal insulation felt, characterized in that, Includes the following steps: Step A: Mix the silicon source, ethanol, deionized water and catalyst in a certain proportion to prepare a silica gel solution; Step B: Immerse one or more layers of glass fiber substrate in the prepared silica gel solution, circulate and recirculate, press and gel age, and dry after modification to obtain glass fiber aerogel insulation felt.

2. The method for preparing a glass fiber aerogel thermal insulation felt as described in claim 1, characterized in that, The silicon source in step A is tetraethyl orthosilicate, tetraethyl orthosilicate 40 or tetraethyl orthosilicate 28, the catalyst is ammonia and ammonium fluoride, and the ethanol content is 60.0-99.99%.

3. The method for preparing a glass fiber aerogel thermal insulation felt as described in claim 2, characterized in that, In step A, the proportions of the components in the silica gel solution are as follows: the mass ratio of silicon source: ethanol: deionized water: ammonia: ammonium fluoride is 100: 50-1000: 0-30: 0-10: 0-10.

4. The method for preparing a glass fiber aerogel thermal insulation felt as described in claim 1, characterized in that, The glass fiber substrate in step B includes silicon dioxide, magnesium oxide, aluminum oxide, calcium oxide, boron oxide, and titanium oxide; its thickness is 0.1-100 mm.

5. The method for preparing a glass fiber aerogel thermal insulation felt as described in claim 1, characterized in that, The circulation in step B involves using a pump to repeatedly circulate the silica gel liquid in the tank to ensure complete impregnation of the glass fiber substrate, with a time of >5 minutes.

6. The method for preparing a glass fiber aerogel thermal insulation felt as described in claim 1, characterized in that, The pressing in step B involves using a rubber block to apply pressure ranging from 5KG to 10KG, pressing from one end of the glass fiber substrate to the other, with each press interval being 3-5cm, and the number of presses being 2-3.

7. The method for preparing a glass fiber aerogel thermal insulation felt as described in claim 1, characterized in that, The aging time in step B is 16-72 hours.

8. The method for preparing a glass fiber aerogel thermal insulation felt as described in claim 1, characterized in that, In step B, the multilayer glass fiber substrates are separated by one or more of the following: nonwoven fabric, monofilament filter cloth, spunlace cloth, fiber cloth, fiber paper, and polyethylene, polypropylene, polyester, polyamide mesh or membrane, and are slowly placed in the modification liquid.

9. The method for preparing a glass fiber aerogel thermal insulation felt as described in claim 1, characterized in that, The drying time in step B is 4-72 hours, and the drying method is any one of supercritical drying, freeze drying, vacuum drying, or room temperature and pressure drying.

10. A glass fiber aerogel thermal insulation felt, characterized in that, The glass fiber aerogel insulation felt prepared by any one of claims 1 to 9 has a thermal conductivity of ≤0.023 W / (m·K) at 25℃ and a compression of 60.4% at 2MPa.