阅读说明：本技术 一种钇稳定二氧化锆气凝胶/纤维复合材料的制备方法 (Preparation method of yttrium-stabilized zirconium dioxide aerogel/fiber composite material ) 是由 王立东 沈亚东 许剑 杨铭 郑张宜 路爱梅 孙立君 于 2021-06-24 设计创作，主要内容包括：本发明属于隔热材料领域,特别是涉及一种钇稳定二氧化锆气凝胶/纤维复合材料的制备方法,所述方法包括：取第一溶剂、水、硝酸氧锆水合物和硝酸钇水合物混合,并进行第一反应,获得第一溶胶；取第二溶剂与所述第一溶胶混合,后加入凝胶促进剂,获得复合溶胶；将纤维毡浸渍于所述复合溶胶中,获得含溶胶纤维毡；所述含溶胶纤维毡置于50～80℃温度中进行凝胶陈化,获得含凝胶纤维毡；将所述含凝胶纤维毡分别浸渍于第三溶剂、第四溶剂和第五溶剂中进行置换,后干燥,获得钇稳定二氧化锆气凝胶/纤维复合材料,该复合材料在1200℃下导热系数为0.147-0.18W/(m·K),具有优异的稳定性和隔热性能。(The invention belongs to the field of heat insulation materials, and particularly relates to a preparation method of a yttrium-stabilized zirconium dioxide aerogel/fiber composite material, which comprises the following steps: mixing a first solvent, water, zirconyl nitrate hydrate and yttrium nitrate hydrate, and carrying out a first reaction to obtain a first sol; mixing a second solvent with the first sol, and then adding a gel accelerator to obtain a composite sol; dipping a fiber felt into the composite sol to obtain a sol-containing fiber felt; placing the sol-containing fiber felt at a temperature of 50-80 ℃ for gel aging to obtain a gel-containing fiber felt; and respectively soaking the gel-containing fibrofelt in a third solvent, a fourth solvent and a fifth solvent for replacement, and then drying to obtain the yttrium-stabilized zirconium dioxide aerogel/fiber composite material, wherein the thermal conductivity of the composite material at 1200 ℃ is 0.147-0.18W/(m.K), and the composite material has excellent stability and heat insulation performance.)

1. A method of preparing an yttrium-stabilized zirconia aerogel/fiber composite, comprising:

mixing a first solvent, water, zirconyl nitrate hydrate and yttrium nitrate hydrate, and carrying out a first reaction to obtain a first sol;

mixing a second solvent with the first sol, and then adding a gel accelerator to obtain a composite sol;

dipping a fiber felt into the composite sol to obtain a sol-containing fiber felt;

carrying out gel aging on the fiber felt containing the sol to obtain a fiber felt containing gel;

and respectively soaking the gel-containing fiber felt in a third solvent, a fourth solvent and a fifth solvent for replacement, and then drying to obtain the yttrium-stabilized zirconium dioxide aerogel/fiber composite material.

2. The method of preparing an yttrium-stabilized zirconia aerogel/fiber composite according to claim 1, wherein the amount of yttrium nitrate hydrate is 19-21% of the amount of zirconyl nitrate hydrate, and the mass of the gel promoter added is 166-265.6% of the amount of zirconyl nitrate hydrate.

3. The method of preparing an yttrium-stabilized zirconium dioxide aerogel/fiber composite according to claim 1 or 2, wherein the zirconyl nitrate hydrate comprises zirconyl nitrate pentahydrate or zirconyl nitrate hexahydrate.

4. The method of preparing an yttrium-stabilized zirconium dioxide aerogel/fiber composite according to claim 1 or 2, wherein the yttrium nitrate hydrate comprises yttrium nitrate pentahydrate or yttrium nitrate hexahydrate.

5. The method of preparing yttrium-stabilized zirconium dioxide aerogel/fiber composite according to claim 1 or 2, wherein the gel promoter is an epoxide.

6. The method of preparing an yttrium-stabilized zirconium dioxide aerogel/fiber composite according to claim 1 or 2, wherein the fiber mat comprises any one of: quartz fiber mats, mullite fiber mats, and alumina fiber mats.

7. The method of preparing an yttrium-stabilized zirconium dioxide aerogel/fiber composite according to claim 1, wherein the drying comprises ethanol supercritical drying, and the parameters of the drying comprise: the drying pressure is 6-8MPa, the supercritical temperature is 250-280 ℃, and the drying time is 20-50 min.

8. The method according to claim 1, wherein the gel-containing fiber mat is immersed in a third solvent, a fourth solvent and a fifth solvent for replacement, and the yttrium-stabilized zirconium dioxide aerogel/fiber composite is obtained, which specifically comprises:

sequentially soaking the gel-containing fibrofelt in a third solvent, a fourth solvent and a fifth solvent for replacement respectively to obtain the yttrium-stabilized zirconium dioxide aerogel/fiber composite material, wherein the replacement conditions of the gel-containing fibrofelt in the third solvent, the fourth solvent and the fifth solvent all comprise: performing replacement for at least 2 times, and performing replacement every 20-26 h.

9. The method of preparing an yttrium-stabilized zirconia aerogel/fiber composite of claim 1, wherein the first, third, and fifth solvents comprise any one of methanol, isopropanol, n-heptane, n-hexane, and absolute ethanol or a mixture of any one thereof with water; the second solvent is formamide solution; the fourth solvent comprises any one of a mixed solution of tetraethyl silicate and absolute ethyl alcohol, a mixed solution of tetraethyl silicate and isopropanol, a mixed solution of tetraethyl silicate and n-heptane and a mixed solution of tetraethyl silicate and n-hexane.

10. An yttrium-stabilized zirconium dioxide aerogel/fiber composite as prepared by the method of preparing an yttrium-stabilized zirconium dioxide aerogel/fiber composite according to any of claims 1 to 8.

Technical Field

The invention belongs to the field of heat insulation materials, and particularly relates to a preparation method of a yttrium-stabilized zirconium dioxide aerogel/fiber composite material.

Background

The aerogel is a nano porous light material and has excellent heat insulation performance. The aerogel has the properties of light weight, small average pore diameter (2-50nm), large specific surface area (100- & lt 1300 & gt 2/g), high porosity (85% -99%), low thermal conductivity (0.01-0.02W/m & K), good chemical stability, strong corrosion resistance and the like, and has very important significance for the research of high-efficiency heat insulation and light materials in the fields of national defense industry, aerospace industry, military field development, agricultural industry and the like; the zirconia crystal has extremely low thermal conductivity, and particularly, the zirconia with stable crystal form is doped, so that the volume shrinkage caused by crystal form transformation can be avoided, and the preparation of the zirconia with stable crystal form at low temperature and high temperature is realized; therefore, the zirconia aerogel combining the common characteristics of zirconia and aerogel is the focus of research in the field of high-temperature heat-insulating materials.

Disclosure of Invention

In view of the above, a method of preparing an yttrium stabilized zirconia aerogel/fiber composite of the present invention is proposed to overcome or at least partially solve the above problems.

The embodiment of the invention provides a preparation method of an yttrium-stabilized zirconium dioxide aerogel/fiber composite material, which comprises the following steps:

mixing a first solvent, water, zirconyl nitrate hydrate and yttrium nitrate hydrate, and carrying out a first reaction to obtain a first sol;

mixing a second solvent with the first sol, and then adding a gel accelerator to obtain a composite sol;

dipping a fiber felt into the composite sol to obtain a sol-containing fiber felt;

carrying out gel aging on the fiber felt containing the sol to obtain a fiber felt containing gel;

and respectively soaking the gel-containing fiber felt in a third solvent, a fourth solvent and a fifth solvent for replacement, and then drying to obtain the yttrium-stabilized zirconium dioxide aerogel/fiber composite material.

Optionally, the mass of the yttrium nitrate hydrate is 19-21% of the mass of the zirconyl nitrate hydrate, and the mass of the gel accelerator added is 166-265.6% of the mass of the zirconyl nitrate hydrate.

Optionally, the zirconyl nitrate hydrate comprises zirconyl nitrate pentahydrate or zirconyl nitrate hexahydrate.

Optionally, the yttrium nitrate hydrate comprises yttrium nitrate pentahydrate or yttrium nitrate hexahydrate.

Optionally, the gel promoter is an epoxide.

Optionally, the fiber mat comprises any one of: quartz fiber mats, mullite fiber mats, and alumina fiber mats.

Optionally, the drying includes ethanol supercritical drying, and the drying parameters include: the drying pressure is 6-8MPa, the supercritical temperature is 250-280 ℃, and the drying time is 20-50 min.

Optionally, the gel-containing fiber mat is respectively immersed in a third solvent, a fourth solvent and a fifth solvent for displacement, so as to obtain the yttrium-stabilized zirconium dioxide aerogel/fiber composite material, which specifically includes:

sequentially soaking the gel-containing fibrofelt in a third solvent, a fourth solvent and a fifth solvent for replacement respectively to obtain the yttrium-stabilized zirconium dioxide aerogel/fiber composite material, wherein the replacement conditions of the gel-containing fibrofelt in the third solvent, the fourth solvent and the fifth solvent all comprise: performing replacement for at least 2 times, and performing replacement every 20-26 h.

Optionally, the first solvent, the third solvent and the fifth solvent comprise any one of methanol, isopropanol, n-heptane, n-hexane and absolute ethyl alcohol or a mixture of any one of them and water; the second solvent is formamide solution; the fourth solvent comprises any one of a mixed solution of tetraethyl silicate and absolute ethyl alcohol, a mixed solution of tetraethyl silicate and isopropanol, a mixed solution of tetraethyl silicate and n-heptane and a mixed solution of tetraethyl silicate and n-hexane.

A yttrium-stabilized zirconium dioxide aerogel/fiber composite material prepared by the preparation method.

One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

according to the preparation method of the yttrium-stabilized zirconium dioxide aerogel/fiber composite material provided by the embodiment of the invention, yttrium-stabilized zirconium dioxide aerogel and fibers are compounded, so that the heat insulation property of the aerogel can be maintained, the strength and toughness of the aerogel can be enhanced, yttrium element is doped to enhance the crystal form stability of zirconium dioxide, tetraethyl silicate is adopted to enhance the skeleton strength of the aerogel during solvent replacement of a zirconium dioxide aerogel/fiber felt composite, a lower heat conductivity coefficient is maintained at a high temperature, and the measured heat conductivity coefficient of the zirconium dioxide aerogel/fiber composite material at 1200 ℃ is more than 0.147W/(m.K), so that the zirconium dioxide aerogel/fiber composite material has good stability and heat insulation property, can be suitable for various complex environments, widens the application range of the heat insulation material, and meets the application in the field of high-temperature heat insulation.

The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

FIG. 1 is a flow chart of a method of making an embodiment of the present invention;

FIG. 2 is a sample of yttrium stabilized zirconia aerogel/fiber composite of example 5 of the present invention after heat treatment at different temperatures.

Detailed Description

The present invention will be described in detail below with reference to specific embodiments and examples, and the advantages and various effects of the present invention will be more clearly apparent therefrom. It will be understood by those skilled in the art that these specific embodiments and examples are for the purpose of illustrating the invention and are not to be construed as limiting the invention.

Throughout the specification, unless otherwise specifically noted, terms used herein should be understood as having meanings as commonly used in the art. Accordingly, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. If there is a conflict, the present specification will control.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.

In the present invention, "first solvent", "second solvent", "third solvent", "fourth solvent", "fifth solvent" and "first reaction" do not refer to a sequential relationship, and are used only as terms for distinction.

Herein, "yttrium nitrate hydrate", "zirconyl nitrate hydrate" are intended to include precursors or derivatives thereof, which technically may not be hydrates, but nevertheless react to form a composite sol containing yttrium and zirconium dioxide.

In order to solve the technical problems, the general idea of the embodiment of the application is as follows:

in an embodiment of the present application, a method for preparing an yttrium-stabilized zirconia aerogel/fiber composite material is shown in fig. 1, and the method includes:

s1, mixing a first solvent, water, zirconyl nitrate hydrate and yttrium nitrate hydrate, and carrying out a first reaction to obtain a first sol;

s2, mixing a second solvent with the first sol, and adding a gel accelerator to obtain a composite sol;

s3, dipping the fiber felt into the composite sol to obtain a sol-containing fiber felt;

s4, carrying out gel ageing on the fiber felt containing the sol to obtain a fiber felt containing gel;

and S5, respectively soaking the gel-containing fiber mat in a third solvent, a fourth solvent and a fifth solvent for replacement, and then drying to obtain the yttrium-stabilized zirconium dioxide aerogel/fiber composite material.

In the embodiment of the application, when the composite sol is prepared, zirconyl nitrate hydrate and yttrium nitrate hydrate are selected to be dissolved in water and a first solvent, the stirring time is 20-40 min, and the zirconyl nitrate hydrate and the yttrium nitrate hydrate are subjected to hydrolysis reaction and polycondensation reaction; and stirring and dissolving the reacted product in a second solvent, adding a gel accelerator, continuously stirring for 5-15 min, and accelerating gel to form composite sol, so that the following reaction is facilitated. After yttrium element is added, the crystal form stability of the composite material is greatly improved.

In the embodiment of the application, the colloid aging (colloidalization) is a phenomenon that colloid is dehydrated and transformed into partial colloid to form stable authigenic minerals due to the increase of pressure and the increase of temperature or the development of time. Aging is advantageous to grow the sol particles to the same size, i.e., small dissolved species grow to larger ones. Aging during the gelation stage makes gelation more complete. The temperature for aging the gel is 50-80 ℃, the environment of 50-80 ℃ is beneficial to smooth aging, the gel is easy to crack due to the overhigh temperature, the aging speed is slow due to the overlow adverse effect, the fiber felt is paved to obtain flat colloid, and the sealing is used for preventing the volatilization of a surface solvent and causing surface cracking. And paving and sealing the fiber felt in the environment at the temperature of 50-80 ℃ for 20-30 hours to obtain the gel aged fiber felt.

As an alternative embodiment, the quality of the yttrium nitrate hydrate accounts for 19-21% of that of the zirconyl nitrate hydrate, and the gel accelerator is added in an amount of 166-265.6% of that of the zirconyl nitrate hydrate.

In the embodiment of the application, the mass content of the gel accelerator is 166-265.6% of that of the zirconyl nitrate hydrate, so that the gel is complete, and the reagent dosage is saved.

As an alternative embodiment, the yttrium nitrate hydrate comprises yttrium nitrate pentahydrate or yttrium nitrate hexahydrate;

as an alternative embodiment, the zirconyl nitrate hydrate comprises zirconyl nitrate pentahydrate or zirconyl nitrate hexahydrate.

In the embodiment of the application, as long as the yttrium nitrate hydrate and the zirconyl nitrate hydrate which can achieve the purpose of the invention can be obtained, the yttrium nitrate pentahydrate or yttrium nitrate hexahydrate, zirconyl nitrate pentahydrate or zirconyl nitrate hexahydrate are common and easy to obtain, and are easy to generate hydrolysis reaction, so that the calculation is convenient, and a reference for selecting the gel accelerator is provided.

In the examples of the application, the gel accelerator is an epoxide, and 1, 2-propylene oxide or 2, 3-butylene oxide can be selected.

As an alternative embodiment, the fiber mat comprises any one of the following: quartz fiber mats, mullite fiber mats, and alumina fiber mats.

In the embodiment of this application, the fibrofelt is as reinforcing phase, and zirconia is as thermal-insulated phase, and the mechanical properties of fibrofelt base member and zirconia aerogel are in the same place, obtain fibre and the compound good thermal insulation material of aerogel and can realize the better application to aerogel material. A quartz fiber mat. Has heat resistance, corrosion resistance and flexibility. High strength retention rate at high temperature, stable size and thermal shock resistance, and can effectively improve the composite hardness of the aerogel.

As an alternative embodiment, the drying comprises ethanol supercritical drying, and the parameters of the drying comprise: the drying pressure is 6-8MPa, the supercritical temperature is 250-280 ℃, and the drying time is 20-50 min.

In the embodiment of the application, the drying pressure is 6-8MPa, the supercritical temperature is 250-280 ℃, the drying efficiency and the drying quality can be improved, and the drying can be completed within 20-50 min.

As an optional embodiment, the gel-containing fiber mat is respectively immersed in a third solvent, a fourth solvent and a fifth solvent for replacement, so as to obtain an yttrium-stabilized zirconia aerogel/fiber composite material, specifically comprising:

in the embodiment of the application, the gel-containing fiber mat is sequentially immersed in a third solvent, a fourth solvent and a fifth solvent for replacement respectively to obtain an yttrium-stabilized zirconium dioxide aerogel/fiber composite material, wherein the replacement conditions of the gel-containing fiber mat in the third solvent, the fourth solvent and the fifth solvent all include: performing replacement for at least 2 times, and performing replacement every 20-26 h.

In the embodiment of the application, the adverse effects of the first replacement and the second replacement are mainly time waste, the production cost and the period are prolonged, and the adverse effects of the too short replacement are incomplete.

As an alternative embodiment, the first solvent, the third solvent and the fifth solvent comprise any one of methanol, isopropanol, n-heptane, n-hexane and absolute ethanol or a mixture of any one of them and water; the second solvent is formamide solution; the fourth solvent comprises any one of a mixed solution of tetraethyl silicate and absolute ethyl alcohol, a mixed solution of tetraethyl silicate and isopropanol, a mixed solution of tetraethyl silicate and n-heptane and a mixed solution of tetraethyl silicate and n-hexane.

In the embodiment of the application, the first solvent is selected because the hydrolysis products of zirconyl nitrate hydrate and yttrium nitrate hydrate can be subjected to polycondensation reaction in the first solvent; the reason for the first replacement with the third solvent is to remove the second solvent by replacement; the reason for the second replacement with the fourth solvent is to strengthen the gel; the reason for the second replacement with the fifth solvent is to remove the fourth solvent by replacement. The formamide solution was chosen for the reason of improving the gel micro-morphology.

In the embodiment of the application, the content of the propylene oxide greatly improves the pore diameter and the specific surface area of the microstructure of the zirconium dioxide aerogel, but when the content is too high, the pore diameter and the specific surface area of the zirconium dioxide aerogel/fiber composite material are not improved any more, the gelation time is shortened, and the sol and fiber composite and preparation operation are not facilitated; when the content is too low, the pore diameter and the specific surface area are not ideal; the content of the propylene oxide greatly improves the aperture and the specific surface area of the microstructure of the zirconium dioxide aerogel, and greatly improves the high-temperature heat-insulating property.

The yttrium-stabilized zirconium dioxide aerogel/fiber composite material is prepared by the preparation method of the yttrium-stabilized zirconium dioxide aerogel/fiber composite material.

In the embodiment of the application, aerogel and quartz fiber are combined well, and the thermal conductivity coefficient of the zirconium dioxide aerogel/fiber composite material at 1200 ℃ is measured to be 0.147-0.18W/(m.K).

The following will describe in detail a process method for improving the drying efficiency of the aerogel thermal insulation material according to the present application with reference to examples, comparative examples and experimental data.

Example 1

A preparation method of yttrium-stabilized zirconium dioxide aerogel/fiber composite material comprises the steps of preparation of composite sol, impregnation of a fiber felt by the composite sol, gel aging and drying,

the preparation of the composite sol comprises the following steps: taking a first solvent, water, zirconyl nitrate hydrate and yttrium nitrate hydrate, stirring, and carrying out a first reaction to obtain uniform sol; the first reaction includes a hydrolysis reaction and a polycondensation reaction. Mixing a second solvent with the uniform sol; adding a gel accelerator, and stirring to obtain the composite sol; the composite sol impregnated fiber felt and gel aging method comprises the following steps:

soaking a fiber felt in the composite sol, taking out after uniform soaking, and obtaining a soaked fiber felt; paving and sealing the impregnated fiber felt, and placing the fiber felt in an environment of 80 ℃ for gel aging to obtain a gel aged fiber felt; soaking the gel-aged fiber mat in a third solvent, and performing replacement every 26 hours for 3 times to obtain a first-time replacement fiber mat; soaking the first-time replacement fiber felt in a fourth solvent, performing replacement every 26 hours for 3 times to obtain a second-time replacement fiber felt; and (3) soaking the second-time replacement fiber felt in a fifth solvent, performing replacement every 26 hours, and performing replacement for 3 times to obtain a third-time replacement fiber felt. The gel accelerator comprises 1-2, propylene oxide.

The first, third, and fifth solvents comprise methanol; the second solvent is formamide solution; the fourth solvent comprises a mixed solution of tetraethyl silicate and absolute ethyl alcohol. The yttrium nitrate hydrate comprises yttrium nitrate hexahydrate; the zirconyl nitrate hydrate includes zirconyl nitrate pentahydrate.

The mass of the yttrium nitrate hydrate is 20% of that of the zirconyl nitrate hydrate, and the mass content of the gel accelerator is 166% of that of the zirconyl nitrate hydrate (calculated by the yttrium doping amount being 20%). The drying comprises ethanol supercritical drying, and the drying parameters are as follows: drying at supercritical temperature of 250 deg.C under 6MPa for 50 min.

Example 2

A preparation method of yttrium-stabilized zirconium dioxide aerogel/fiber composite material comprises the steps of preparation of composite sol, impregnation of a fiber felt by the composite sol, gel aging and drying,

the preparation of the composite sol comprises the following steps:

taking a first solvent, water, zirconyl nitrate hydrate and yttrium nitrate hydrate, stirring, and carrying out a first reaction to obtain uniform sol; the first reaction includes a hydrolysis reaction and a polycondensation reaction. Mixing a second solvent with the uniform sol; adding a gel accelerator, and stirring to obtain the composite sol;

the composite sol impregnated fiber felt and gel aging method comprises the following steps:

soaking a fiber felt in the composite sol, taking out after uniform soaking, and obtaining a soaked fiber felt; paving and sealing the impregnated fiber felt, and placing the fiber felt in an environment at 65 ℃ for gel aging to obtain a gel aged fiber felt; soaking the gel-aged fiber mat in a third solvent, and performing replacement every 24 hours for 4 times to obtain a first replacement fiber mat; soaking the first-time replacement fiber felt in a fourth solvent, performing replacement every 24 hours for 3 times to obtain a second-time replacement fiber felt; and (3) soaking the second-time replacement fiber felt in a fifth solvent, performing replacement every 24 hours, and performing replacement for 3 times to obtain a third-time replacement fiber felt.

The fiber felt is a quartz fiber felt. The gel accelerator comprises 1-2, propylene oxide. The mass of the yttrium nitrate hydrate is 20% of that of the zirconyl nitrate hydrate, and the mass content of the gel accelerator is 265.6% of that of the zirconyl nitrate hydrate (calculated by the yttrium doping amount being 20%). The first, third, and fifth solvents comprise isopropyl alcohol; the second solvent is formamide solution; the fourth solvent includes a mixed solution of tetraethyl silicate and n-heptane. The yttrium nitrate hydrate comprises yttrium nitrate pentahydrate; the zirconyl nitrate hydrate comprises zirconyl nitrate hexahydrate.

The drying comprises ethanol supercritical drying, and the drying parameters are as follows: drying pressure is 8MPa, supercritical temperature is 280 ℃, and drying time is 50 min.

Example 3

1) Weighing 3000mL of absolute ethyl alcohol and 1000mL of deionized water, weighing 200g of zirconyl nitrate pentahydrate and 40g of yttrium nitrate hexahydrate, adding the raw material reagents into a reaction kettle together, and stirring until the raw material reagents are completely dissolved; weighing 24mL of formamide, adding into the mixed solution, and controlling the stirring time to be 30 min; and (3) quickly adding 400mL of 1-2, propylene oxide into the sol, and continuously stirring for 10min to obtain the composite sol.

2) Dipping the cut quartz fiber felt of 300 multiplied by 200 multiplied by 30 into the sol, taking out after the dipping is completed, and paving on a flat plate. And putting the impregnated quartz fibrofelt into a plastic box, pressing and sealing by using an acrylic plate and a weight, and transferring into a 70 ℃ drying oven for gel ageing for 24 hours to obtain an aged gel/quartz fibrofelt sample.

Adding about 1.5L of absolute ethyl alcohol for solvent replacement and sealing, transferring into a 70 ℃ oven, replacing once every 24h for three times; adding 1.5L of tetraethyl silicate/ethanol solution with volume fraction of 15% for solvent replacement and sealing, transferring into a 70 ℃ oven, replacing once every 24h, and replacing twice in total; adding about 1.5L of absolute ethyl alcohol for solvent replacement, sealing, transferring into an oven at 70 ℃, replacing once every 24h for three times.

3) And (3) putting the sample subjected to solvent replacement into an ethanol supercritical dryer, wherein the drying pressure is 7MPa, the supercritical temperature is 260 ℃, and the drying time is 40 min. And obtaining the yttrium-stabilized zirconium dioxide aerogel/quartz fiber composite material.

The prepared yttrium-stabilized zirconium dioxide aerogel/quartz fiber felt composite material with 20% of yttrium doping amount and 166% of epoxypropane addition amount of zirconyl nitrate hydrate mass has the advantages of flat appearance, no wrinkle, and good combination of aerogel and quartz fiber.

Example 4

The main steps are the same as example 1, except that 520ml of propylene oxide is added into the sol in step 1), and finally the yttrium-stabilized zirconium dioxide aerogel/quartz fiber composite material with the doping amount of propylene oxide being 215.8% of the mass of the zirconyl nitrate hydrate is obtained.

The prepared yttrium-stabilized zirconium dioxide aerogel/quartz fiber composite material is flat in appearance, free of wrinkles and good in combination of aerogel and quartz fiber.

Example 5

The main steps are the same as example 3, except that 640ml of propylene oxide is added into the sol in step 1), and finally the yttrium-stabilized zirconium dioxide aerogel/quartz fiber composite material with the doping amount of propylene oxide being 265.6% of the mass of the zirconyl nitrate hydrate is obtained.

The prepared yttrium-stabilized zirconium dioxide aerogel/quartz fiber composite material is flat in appearance without folds, the aerogel and the quartz fiber are well combined, and the thermal conductivity coefficient of the zirconium dioxide aerogel/quartz fiber composite material at 1200 ℃ is measured to be 0.147W/(m.K).

In the invention, the optimum formula is that the doping amount of yttrium is 20%, and the addition amount of propylene oxide is 265.6% of the mass of zirconyl nitrate hydrate, namely the formula corresponding to the embodiment, at this time, the aerogel and the quartz fiber are well combined, and the thermal conductivity coefficient of the composite material at 1200 ℃ is 0.147W/(m.K).

Comparative example 1

In the same manner as in example 3, except that yttrium nitrate hexahydrate was not added, an equal amount of zirconyl nitrate hydrate was used instead, example 4 was repeated.

Comparative example 2

The aged gel/quartz fiber mat sample was dried directly without displacement in the same manner as in example 3. The rest is the same as example 4.

Comparative example 3

In the same manner as in example 3, the replacement operation was carried out, but in this comparative example, the following procedure was employed: adding about 1.5L of absolute ethyl alcohol for solvent replacement and sealing, transferring into a 70 ℃ oven, replacing once every 24h for three times; adding 1.5L of absolute ethyl alcohol for solvent replacement and sealing, transferring into a 70 ℃ oven, replacing once every 24h, and replacing twice; about 1.5L of absolute ethanol was added for solvent replacement and sealed, and the mixture was transferred to a 70 ℃ oven for replacement once every 24 hours for a total of three times. The rest is the same as example 3.

Performance detection of yttrium-stabilized zirconium dioxide aerogel/fiber composite material

The yttrium-stabilized zirconia aerogel/fiber composites prepared in examples 1 to 6 and comparative examples 1 to 3 were tested and the test results are shown in table 1.

Table 1, comparative table of the test results of examples and comparative examples.

From the data in table 1, it can be seen that:

according to the yttrium-stabilized zirconium dioxide aerogel/fiber composite material provided by the embodiment of the invention, yttrium-stabilized zirconium dioxide aerogel and fibers are compounded, a low thermal conductivity coefficient is kept at a high temperature, the thermal conductivity coefficient of the zirconium dioxide aerogel/fiber composite material at 1200 ℃ is measured to be more than 0.147W/(m.K), and meanwhile, the highest use temperature of the composite material is increased.

From the data in comparative examples 1-3, it can be seen that:

from the data of comparative example 1, it is understood that the addition of yttrium element results in a significant increase in the thermal conductivity at 1200 ℃, indicating that the addition of yttrium element is effective in improving the thermal stability and high-temperature thermal insulation performance of the material.

From the data of comparative example 2, it is clear that the high temperature insulation performance of the material is reduced without substitution.

From the data of comparative example 3, it is clear that the second replacement of the fiber mat obtained in the replacement process, without using the fourth solvent, and with using the third solvent, resulted in a slight decrease in the high temperature insulation performance of the material.

Detailed description of the drawings 1-2:

as shown in fig. 1, the preparation method provided by the present invention can effectively maintain the thermal insulation property of the aerogel and enhance the strength and toughness of the aerogel, thereby obtaining a thermal insulation material with a low thermal conductivity at high temperature.

Fig. 2 shows that the yttrium-stabilized zirconia aerogel/fiber composite material of example 5 of the present invention is heat-treated at different temperatures, and the heat treatment is performed at 500, 800, and 1200 ℃ for 2 hours from left to right in the figure, and no significant shrinkage deformation occurs at 1200 ℃, indicating that the thermal stability of the material is good.

Finally, it should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.