CN110157047B - Curdlan-silicon dioxide composite water/aerogel and preparation method and application thereof - Google Patents

Curdlan-silicon dioxide composite water/aerogel and preparation method and application thereof Download PDF

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CN110157047B
CN110157047B CN201910506434.1A CN201910506434A CN110157047B CN 110157047 B CN110157047 B CN 110157047B CN 201910506434 A CN201910506434 A CN 201910506434A CN 110157047 B CN110157047 B CN 110157047B
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curdlan
silicon dioxide
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water
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CN110157047A (en
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孙燕
伊佳伟
寿周翔
杨柳
任迎港
张燕妮
王磊
方晓军
夏远乾
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Zhanjiang Dashu Agricultural Technology Co ltd
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Qianjiang College of Hangzhou Normal University
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    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/02—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques
    • C08J3/03—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media
    • C08J3/075—Macromolecular gels
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
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    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/34—Silicon-containing compounds
    • C08K3/36—Silica
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
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Abstract

The invention discloses curdlan-silicon dioxide composite water/aerogel and a preparation method and application thereof. The existing silica gel has the problem of poor toughness, and the conventional modification often needs crosslinking. The curdlan-silica composite hydrogel comprises curdlan and silica. The curdlan and the silicon dioxide form an interpenetrating network structure. The curdlan-silica composite aerogel comprises curdlan and silica. The curdlan and the silicon dioxide form an interpenetrating network structure. The invention utilizes different gelling types of curdlan at different temperatures, and also utilizes the two characteristics of stable dispersion of the curdlan in water and good dissolution in aqueous alkali, and simultaneously utilizes a sol-gel method to form composite gel with interpenetrating network structure of curdlan and silicon dioxide under alkaline conditions.

Description

Curdlan-silicon dioxide composite water/aerogel and preparation method and application thereof
Technical Field
The invention belongs to the technical field of composite materials, and particularly relates to two main aspects: one is related to a curdlan-silicon dioxide composite hydrogel material and a preparation method and application thereof in the fields of plant cultivation, crop planting and the like; the other relates to a curdlan-silicon dioxide composite aerogel material, a preparation method and application thereof in the sewage treatment field and the industrial field, and the curdlan-silicon dioxide composite aerogel material can be mainly used as an adsorption material, an isolation material and a coating material.
Background
Curdlan (Curdlan) is a microbial polysaccharide produced by fermentation of Alcaligenes faecalis (Alcaligenes faecalis). Curdlan is a novel polysaccharide produced by microbial fermentation after xanthan gum and gellan gum. Curdlan gum was commercially produced in japan in 1989 and recommended by the american Food and Drug Administration (FDA) for use in food in 1996. The polysaccharide has no branched chain, is D-dextran connected by beta- (1,3) glycosidic bond, and has molecular formula of (C)6H10O5) n is the same as the formula (I). Natural curdlan molecular weights range from tens of thousands to millions. The solid curdlan is white powder, non-toxic and insoluble in water, but can be uniformly dispersed in water to form a stable water dispersion system which is soluble in an alkali solution and a DMSO aqueous solution. Curdlan gel has unique characteristics, is completely different from other curdlan properties, forms thermally reversible low-strength gel at about 55 ℃ according to the heating temperature of aqueous suspension, and forms thermally irreversible high-strength gel at the temperature of more than 80 ℃. The existing silica gel has the problem of poor toughness, and the conventional modification often needs crosslinking.
Disclosure of Invention
The invention aims to provide curdlan-silicon dioxide composite water/aerogel and a preparation method and application thereof.
The curdlan-silica composite hydrogel comprises curdlan and silica. The curdlan and the silicon dioxide form an interpenetrating network structure. The mass fraction of curdlan is 0.03-1.5%; the mass fraction of the silicon dioxide is 7-9%.
The curdlan-silica composite aerogel comprises curdlan and silica. The curdlan and the silicon dioxide form an interpenetrating network structure. The mass fraction of curdlan is 0.3-10%; the mass fraction of the silicon dioxide is 40-70%.
The preparation method of the curdlan-silicon dioxide composite hydrogel comprises the following steps:
step one, dispersing curdlan glue in water or dissolving in an alkali solution to obtain a curdlan glue dispersion liquid or a curdlan alkali solution.
Step two, dissolving tetraethyl orthosilicate in ethanol. And adjusting the pH value to 3-5 by using an acid solution to hydrolyze tetraethyl orthosilicate at the temperature of 20-60 ℃ to form silicic acid.
Step three, catalyzing silicic acid obtained in the step two with an alkaline substance to perform dehydration polycondensation; and (3) dripping the curdlan glue dispersion liquid or the curdlan glue alkali solution obtained in the step one into a silicic acid dehydration polycondensation system to obtain a hydrogel prototype.
And step four, sealing the opening, and placing the opening in a constant-temperature water bath at the temperature of 30-100 ℃ for 6-24 hours to obtain the curdlan-silicon dioxide composite hydrogel.
Further, in the first step, under the condition that the curdlan is dispersed in water, the mass concentration of the curdlan is 0.10-5.0%; under the condition that the curdlan is dissolved in the alkali solution, the mass ratio of the curdlan to the alkali solution is 1: 6-1: 4; the curdlan can be continuously stirred in the process of dispersing into water or dissolving in an alkali solution, and the stirring speed is 600-800 rpm.
The alkaline solution in the step one adopts ammonia water, sodium hydroxide aqueous solution, trisodium phosphate aqueous solution or tricalcium phosphate aqueous solution, and the mass concentration of the alkaline solution is 0.10-10.0%. And the acid solution in the second step adopts hydrofluoric acid, acetic acid or hydrochloric acid. The alkaline substance in the third step adopts sodium hydroxide, trisodium phosphate or tricalcium phosphate.
Further, in the second step, the hydrolysis process is continuously stirred, and the stirring speed is 200-500 rpm.
In the second step, the mass ratio of tetraethyl orthosilicate to ethanol is 1: 5-1: 0.
Further, in the third step, in the process of dripping the curdlan water dispersion liquid or the curdlan alkali solution, stirring is continuously carried out until gel is formed.
In the third step, the mass ratio of curdlan in the first step to tetraethyl orthosilicate in the second step is as follows: 1: 1000-1: 10.
The preparation method of the curdlan-silicon dioxide composite aerogel comprises the following steps:
and (3) sequentially carrying out aging, solvent replacement and freeze drying on the curdlan-silicon dioxide composite hydrogel to obtain the curdlan-silicon dioxide composite aerogel.
Further, before aging the curdlan-silica composite hydrogel, the surface of the curdlan-silica composite hydrogel is covered with water and tetraethyl orthosilicate. The aging operation is carried out for 8-48 h at 20-100 ℃. Before the solvent replacement, the curdlan-silicon dioxide composite hydrogel is subjected to surface modification by using a coupling agent. The coupling agent is hexamethyldisilazane or Y- (methacryloyloxy) propyl trimethoxy silane. And (3) carrying out solvent replacement by using n-hexane for 8-24 h. The temperature for freeze-drying was-75 ℃.
The curdlan-silicon dioxide composite hydrogel is applied as a culture medium for plant cultivation.
The application of curdlan-silicon dioxide composite aerogel as an adsorption material, an isolation material and a coating material.
The invention has the beneficial effects that:
1. the invention utilizes different gel forming types (reversible or not) of curdlan at different temperatures and simultaneously utilizes a sol-gel method to form silicon dioxide hydrogel under the alkaline condition, thereby preparing the curdlan-silicon dioxide composite hydrogel with an interpenetrating network structure.
2. The invention utilizes two remarkable characteristics of excellent dispersion of curdlan in water and good dissolution in alkali solution to prepare different curdlan solution systems, and then the curdlan solution systems and silicon dioxide are cooperatively gelatinized on the basis to prepare different gel materials, so that different characteristics and different transparencies are endowed to the gel.
3. The curdlan-silicon dioxide composite hydrogel has the functions of water retention and drug loading sustained release. Meanwhile, the hydrogel also has the characteristic of excellent light transmittance, so that when the hydrogel is used as a culture medium for plant cultivation, workers can clearly observe the growth condition of roots and track the growth dynamics of plants.
4. The invention utilizes a solvent replacement method, the reversibility of gelling of curdlan at low temperature and a freeze-drying method to prepare a series of curdlan-silicon dioxide composite aerogels with different interpenetrating structures.
5. The curdlan-silicon dioxide composite aerogel obtained by the invention has stronger toughness and can be used as an adsorption material, an isolation material and a coating material. When used as an adsorbent, the adsorbent can adsorb heavy metals or organic solvents. The organic solvent is gasoline, toluene, xylene, carbon tetrachloride, acetone or chloroform, and the oil absorption rate is 10-50 g/g.
6. The raw materials used in the invention have rich sources, are nontoxic, green and environment-friendly, have low price, mild production conditions, simple steps and high production efficiency, and are suitable for large-scale industrial production.
Drawings
FIG. 1 is a graph showing the infrared spectroscopic analysis (FTIR spectrum) of the hydrogels obtained in examples 1-1 to 1-3. Wherein, in FIG. 1, the A curve corresponds to the hydrogel obtained in example 1-1, the B curve corresponds to the hydrogel obtained in example 1-2, and the C curve corresponds to the hydrogel obtained in example 1-2
The hydrogels obtained in examples 1 to 3 correspond.
FIG. 2 is a graph of infrared spectroscopic analysis (FTIR spectrum) of the hydrogels obtained in examples 1 to 4.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
Example 1:
example 1-1:
the preparation method of the curdlan-silicon dioxide composite water/aerogel comprises the following steps:
step one, 0.03g of curdlan is dispersed in 28mL of water under stirring to obtain a curdlan dispersion liquid with the mass dispersion concentration of 0.1%.
Step two, dissolving tetraethyl orthosilicate in ethanol, and adjusting the pH value of the system to 3 by using 0.1mol/L dilute acetic acid to hydrolyze the tetraethyl orthosilicate at 20 ℃ to form silicic acid.
And step three, adjusting the pH value of the silicic acid obtained in the step two to 6-7 by using sodium hydroxide, and gradually dripping the curdlan glue dispersion liquid obtained in the step one into the silicic acid while stirring so as to uniformly disperse the curdlan glue in the silicic acid, thereby obtaining a hydrogel prototype.
Step four, sealing the hydrogel embryonic form obtained in the step three by using a preservative film, and then placing the hydrogel embryonic form in a constant-temperature water bath at 30 ℃ for 12 hours to form the wet hydrogel. The mass fraction of curdlan in the obtained hydrogel was 0.03%, and the mass fraction of silica was 7%.
Examples 1 to 2:
step one, 0.1g of curdlan is dispersed in 9.9mL of water under stirring to obtain a curdlan dispersion liquid with a mass dispersion concentration of 1.0%.
Step two, dissolving tetraethyl orthosilicate in ethanol, and adjusting the pH value of the system to 4 by using 0.5mol/L dilute acetic acid to hydrolyze the tetraethyl orthosilicate at 30 ℃ to form silicic acid.
And step three, adjusting the pH value of the silicic acid obtained in the step two to 6-7 by using sodium hydroxide, and gradually dripping the curdlan glue dispersion liquid obtained in the step one into the silicic acid while stirring so as to uniformly disperse the curdlan glue in the silicic acid, thereby obtaining a hydrogel prototype.
Step four, sealing the hydrogel embryonic form obtained in the step three by using a preservative film, and then placing the hydrogel embryonic form in a constant-temperature water bath at 60 ℃ for 6 hours to form the wet hydrogel. The mass fraction of curdlan in the obtained hydrogel was 0.14%, and the mass fraction of silica was 8.9%.
Examples 1 to 3:
step one, 1g of curdlan is dispersed in 19mL of water under stirring to obtain a curdlan dispersion liquid with the mass dispersion concentration of 5.0%.
Step two, dissolving tetraethyl orthosilicate in ethanol, and adjusting the pH value of the system to 5 by using 1mol/L dilute acetic acid to hydrolyze the tetraethyl orthosilicate at 60 ℃ to form silicic acid.
And step three, adjusting the pH value of the silicic acid obtained in the step two to 6-7 by using sodium hydroxide, and gradually dripping the curdlan glue dispersion liquid obtained in the step one into the silicic acid while stirring so as to uniformly disperse the curdlan glue in the silicic acid, thereby obtaining a hydrogel prototype.
Step four, sealing the hydrogel embryonic form obtained in the step three by using a preservative film, and then placing the hydrogel embryonic form in a constant-temperature water bath at 90 ℃ for 3 hours to form wet hydrogel. The mass fraction of curdlan in the obtained hydrogel was 1.5%, and the mass fraction of silica was 9%.
Examples 1 to 4:
step one, dispersing 0.03g of curdlan in 20mL of ammonia water solution with the mass fraction of 1% under stirring to obtain a curdlan alkali solution with the mass concentration of 0.1%.
Step two, dissolving tetraethyl orthosilicate in ethanol, and adjusting the pH value of the system to 3 by using 0.1mol/L dilute acetic acid to hydrolyze the tetraethyl orthosilicate at 20 ℃ to form silicic acid.
And step three, adjusting the pH value of the silicic acid obtained in the step two to 6-7 by using sodium hydroxide, and gradually dripping the curdlan alkali solution obtained in the step one into the silicic acid while stirring so as to uniformly disperse the curdlan in the silicic acid, thereby obtaining a hydrogel prototype.
Step four, sealing the hydrogel embryonic form obtained in the step three by using a preservative film, and then placing the hydrogel embryonic form in a constant-temperature water bath at 30 ℃ for 12 hours to form the wet hydrogel. The mass fraction of curdlan in the obtained hydrogel was 0.04%, and the mass fraction of silica was 8.7%.
Examples 1 to 5:
step one, 0.1g of curdlan is dispersed in 20mL of 1% ammonia water solution under stirring to obtain a curdlan alkali solution with the mass concentration of 1.0%.
Step two, dissolving tetraethyl orthosilicate in ethanol, and adjusting the pH value of the system to 4 by using 0.5mol/L dilute acetic acid to hydrolyze the tetraethyl orthosilicate at 30 ℃ to form silicic acid.
And step three, adjusting the pH value of the silicic acid obtained in the step two to 6-7 by using sodium hydroxide, and gradually dripping the curdlan alkali solution obtained in the step one into the silicic acid while stirring so as to uniformly disperse the curdlan in the silicic acid, thereby obtaining a hydrogel prototype. Curdlan forms an interpenetrating network structure in silicic acid.
Step four, sealing the hydrogel embryonic form obtained in the step three by using a preservative film, and then placing the hydrogel embryonic form in a constant-temperature water bath at 60 ℃ for 6 hours to form the wet hydrogel. The mass fraction of curdlan in the obtained hydrogel was 0.12%, and the mass fraction of silica was 7.8%.
Examples 1 to 6:
step one, dispersing 1g of curdlan in 19mL of ammonia water solution with the mass fraction of 1% under stirring to obtain a curdlan alkali solution with the mass concentration of 5.0%.
Step two, dissolving tetraethyl orthosilicate in ethanol, and adjusting the pH value of the system to 5 by using 1.0mol/L dilute acetic acid to hydrolyze the tetraethyl orthosilicate at 60 ℃ to form silicic acid.
And step three, adjusting the pH value of the silicic acid obtained in the step two to 6-7 by using sodium hydroxide, and gradually dripping the curdlan alkali solution obtained in the step one into the silicic acid while stirring so as to uniformly disperse the curdlan in the silicic acid, thereby obtaining a hydrogel prototype. Forming an organic-inorganic composite hydrogel material.
And step four, sealing the hydrogel embryonic form obtained in the step three by using a preservative film, and placing the hydrogel embryonic form in a constant-temperature water bath at 90 ℃ for 45min to form the wet hydrogel. The mass fraction of curdlan in the obtained hydrogel was 1.3%, and the mass fraction of silica was 7.8%.
The infrared spectra of the hydrogels obtained in examples 1-1 to 1-4 are shown in FIGS. 1 and 2. The hydrogels obtained in examples 1-1 to 1-6 can be used as plant and crop culture media because curdlan is in polysaccharide molecular conformation, wherein curdlan can be decomposed by microorganisms and finally becomes nutrient substances required by plant growth; in addition, the obtained hydrogel has better light transmittance, can clearly observe the growth condition of roots, and simultaneously has the functions of water retention or drug loading sustained release. In addition, the hydrogels obtained in examples 1-1 to 1-6 are convenient to store and transport, and can be used as a crop cultivation medium, due to good water retention and small molecule drug loading, so that the water consumption and drug application amount in the crop planting process can be reduced, the cost is saved, and the environmental pollution is greatly reduced.
Example 2:
example 2-1:
step one, the surface of the hydrogel obtained in any one of the embodiments 1-1 to 1-6 is covered with water and tetraethyl orthosilicate, and the hydrogel is aged at 30 ℃ for 24 hours to obtain covered gel.
And step two, carrying out surface modification on the hydrogel for 12 hours at room temperature by using 5g of Hexamethyldisilazane (HMDZ), and then carrying out solvent replacement on the covered gel by using n-hexane, wherein the solvent replacement time is 24 hours. And then, freeze-drying to obtain the dry aerogel.
In the case of using the hydrogel of example 1-1 in step one, the mass fraction of curdlan in the obtained aerogel was 0.3%, and the mass fraction of silica was 60%.
Example 2-2:
step one, the surface of the hydrogel obtained in any one of the embodiments 1-1 to 1-6 is covered with water and tetraethyl orthosilicate, and the hydrogel is aged at 60 ℃ for 12 hours to obtain covered gel.
And step two, carrying out surface modification on the hydrogel for 12 hours at room temperature by using 5g of Hexamethyldisilazane (HMDZ), and then carrying out solvent replacement on the covered gel by using n-hexane, wherein the solvent replacement time is 24 hours. And then, freeze-drying to obtain the dry aerogel.
In the case of using the hydrogel of examples 1 to 2 in step one, the mass fraction of curdlan in the aerogel obtained was 1%, and the mass fraction of silica was 60%.
Examples 2 to 3:
step one, the surface of the hydrogel obtained in any one of the embodiments 1-1 to 1-6 is covered with water and tetraethyl orthosilicate, and the hydrogel is aged for 6 hours at 90 ℃ to obtain covered gel.
And step two, carrying out surface modification on the hydrogel for 12 hours at room temperature by using 5g of Hexamethyldisilazane (HMDZ), and then carrying out solvent replacement on the covering gel by using n-hexane for 24 hours. And then, freezing and drying to obtain the dry aerogel.
In the case of using the hydrogels of examples 1 to 3 in step one, the mass fraction of curdlan in the resulting aerogel was 10%, and the mass fraction of silica was 60%.
Examples 2 to 4:
step one, the surface of the hydrogel obtained in any one of the embodiments 1-1 to 1-6 is covered with water and tetraethyl orthosilicate, and the hydrogel is aged at 30 ℃ for 24 hours to obtain covered gel.
And step two, carrying out surface modification on the hydrogel for 12 hours at room temperature by using 5g of Hexamethyldisilazane (HMDZ), and then carrying out solvent replacement on the covered gel by using n-hexane, wherein the solvent replacement time is 24 hours. And then, freezing and drying to obtain the dry aerogel.
In the case of using the hydrogels of examples 1 to 4 in step one, the mass fraction of curdlan in the resulting aerogel was 0.3%, and the mass fraction of silica was 60%. The oil absorption of the gasoline is 10.0 g/g.
Examples 2 to 5:
step one, the surface of the hydrogel obtained in any one of the embodiments 1-1 to 1-6 is covered with water and tetraethyl orthosilicate, and the hydrogel is aged at 60 ℃ for 12 hours to obtain covered gel.
And step two, carrying out surface modification on the hydrogel for 12 hours at room temperature by using 5g of Hexamethyldisilazane (HMDZ), and then carrying out solvent replacement on the covered gel by using n-hexane, wherein the solvent replacement time is 24 hours. And then, washing the covering gel after the solvent replacement by using ethanol, and freeze-drying to obtain the dry aerogel.
In the case of using the hydrogels of examples 1 to 5 in step one, the mass fraction of curdlan in the resulting aerogel was 1%, and the mass fraction of silica was 60%. The oil absorption for toluene was 40.6 g/g.
Examples 2 to 6:
step one, the surface of the hydrogel obtained in any one of the embodiments 1-1 to 1-6 is covered with water and tetraethyl orthosilicate, and the hydrogel is aged for 6 hours at 90 ℃ to obtain covered gel.
And step two, carrying out surface modification on the hydrogel for 12 hours at room temperature by using 5g of Hexamethyldisilazane (HMDZ), and then carrying out solvent replacement on the covered gel by using n-hexane, wherein the solvent replacement time is 24 hours. And then, washing the covering gel after the solvent replacement by using ethanol, and freeze-drying to obtain the dry aerogel.
In the case of using the hydrogels of examples 1 to 6 in step one, the mass fraction of curdlan in the resulting aerogel was 10%, and the mass fraction of silica was 60%. The oil absorption for chloroform was 50.0 g/g.
The aerogels obtained in examples 2-1 to 2-6 can be used as an adsorbing material, a spacer material and a coating material. Because the inorganic silicon dioxide polymer is modified in the obtained aerogel through the organic high-molecular curdlan, the area of the interface between the inorganic silicon network and the organic high-molecular network is increased, the acting force between the interfaces is strengthened, and the sharp interface is not obvious. Therefore, the toughness of the aerogel obtained by the invention is far higher than that of the conventional silica gel, and the brittleness defect of the silica aerogel is changed. Therefore, the aerogels obtained in examples 2-1 to 2-6 can be more conveniently used and applied in the fields of adsorption materials, isolation materials and coating materials.

Claims (4)

1. The application of curdlan-silicon dioxide composite hydrogel as a plant cultivation medium is characterized in that: the composite hydrogel comprises curdlan and silica; the curdlan and the silicon dioxide form an interpenetrating network structure; the mass fraction of curdlan is 0.03-1.5%; the mass fraction of the silicon dioxide is 7% -9%; the curdlan and the silicon dioxide are gelled under neutral or acidic conditions; the preparation process of the curdlan-silicon dioxide composite hydrogel comprises the following steps:
dispersing curdlan in water or dissolving in an alkali solution to obtain a curdlan dispersion liquid or a curdlan solution;
step two, dissolving tetraethyl orthosilicate in ethanol; adjusting the pH value to 3-5 by using an acid solution to hydrolyze tetraethyl orthosilicate at the temperature of 20-60 ℃ to form silicic acid;
step three, catalyzing silicic acid obtained in the step two with an alkaline substance to perform dehydration polycondensation; dripping the curdlan glue dispersion liquid or the curdlan glue alkali solution obtained in the step one into a silicic acid dehydration polycondensation system to obtain a hydrogel prototype;
and step four, sealing the opening, and placing the opening in a constant-temperature water bath at the temperature of 30-100 ℃ for 6-24 hours to obtain the curdlan-silicon dioxide composite hydrogel.
2. Use according to claim 1, characterized in that: in the first step, under the condition that the curdlan is dispersed in water, the mass concentration of the curdlan is 0.10-5.0%; under the condition that the curdlan is dissolved in the alkali solution, the mass ratio of the curdlan to the alkali solution is 1: 6-1: 4; continuously stirring the curdlan in the process of dispersing the curdlan in water or dissolving the curdlan in an alkali solution, wherein the stirring speed is 600-800 rpm;
the alkaline solution in the first step is ammonia water, a sodium hydroxide aqueous solution, a trisodium phosphate aqueous solution or a tricalcium phosphate aqueous solution, and the mass concentration of the alkaline solution is 0.10-10.0%; the acid solution in the second step adopts hydrofluoric acid, acetic acid or hydrochloric acid; the alkaline substance in the third step adopts sodium hydroxide, trisodium phosphate or tricalcium phosphate.
3. Use according to claim 1, characterized in that: in the second step, stirring is continuously carried out in the hydrolysis process, and the stirring speed is 200-500 rpm; the mass ratio of tetraethyl orthosilicate to ethanol is 1: 5-1: 0.
4. Use according to claim 1, characterized in that: in the third step, continuously stirring in the process of dropwise adding the curdlan glue dispersion liquid or the curdlan glue solution; the mass ratio of curdlan in the step one to tetraethyl orthosilicate in the step two is as follows: 1: 1000-1: 10.
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