阅读说明：本技术 一种耐高温遮光用石英玻璃板材的生产方法 (Production method of high-temperature-resistant shading quartz glass plate ) 是由 邵长贵 金小宁 于 2021-11-10 设计创作，主要内容包括：本发明公开了一种耐高温遮光用石英玻璃板材的生产方法,属于玻璃板材技术领域。所述石英玻璃的生产方法为：制备不透明石英玻璃；利用正硅酸乙酯、无水乙醇、蒸馏水、盐酸和氨水和甲酰胺制备凝胶；将不透明石英玻璃和凝胶一起烧结制备石英玻璃。本发明通过添加盐酸、氨水、甲酰胺,溶胶的粒子表面可以吸附一定数量盐酸中的H～(+),并产生具有三个配位的Si-OH,氨水中的OH～(-)可以通过振动以及化学键断裂产生具有三个配位的SiO～(-),SiO～(-)进攻其他溶胶分子中心的Si原子,进而发生缩聚反应；加入甲酰胺后,体系产生的前驱体为少于6个硅原子的低聚合物,进一步发生缩聚反应,使得体系的交联度增大,从而达到提高体系的密度和强度的目的。(The invention discloses a production method of a high-temperature-resistant shading quartz glass plate, and belongs to the technical field of glass plates. The production method of the quartz glass comprises the following steps: preparing opaque quartz glass; preparing gel from tetraethoxysilane, absolute ethyl alcohol, distilled water, hydrochloric acid, ammonia water and formamide; the opaque quartz glass and the gel are sintered together to prepare the quartz glass. By adding hydrochloric acid, ammonia water and formamide, the surfaces of the sol particles can adsorb a certain amount of H in hydrochloric acid + And generates Si-OH with three coordination, OH in ammonia ‑ It is possible to produce SiO with three coordination by vibration and chemical bond cleavage ‑ ，SiO ‑ Attack Si atoms of other sol molecule centers and further carry out polycondensation reaction; after formamide is added, the precursor generated by the system is oligomer with less than 6 silicon atoms, and the polycondensation reaction is further carried out, so that the crosslinking degree of the system is increased, and the crosslinking degree of the system is increasedThereby achieving the purpose of improving the density and the strength of the system.)

1. The production method of the high-temperature-resistant shading quartz glass plate is characterized by comprising the following steps of:

s1: mixing graphite powder and amorphous silicon dioxide powder in a volume ratio of (1-2) to (1.5-2.5), molding the mixed powder, heating at a temperature at which the graphite powder disappears to remove the graphite powder, and grinding the silicon dioxide powder into micropowder slurry with a particle size of 0-150 microns by using a non-metal medium ball mill. Casting and molding the micro-powder slurry in a mold, and sintering until air holes contained in a sintered body become closed holes to obtain opaque quartz glass;

s2: adding tetraethoxysilane, absolute ethyl alcohol and distilled water into a container, uniformly stirring, adding a catalyst into the mixed solution under the state of constant-temperature water bath at 45-55 ℃, continuously stirring until the solution becomes clear, then adding ammonia water into the mixed solution, continuously stirring until sol appears, then stopping stirring, pouring the sol into a mold, and drying the sol in a constant-temperature box to obtain gel;

s3: pouring a part of the gel obtained in the step S2 into a mold, and putting the opaque quartz glass obtained in the step S1 onto the gel, and pouring the other part of the gel to obtain a base plate;

s4: and slowly heating the base plate for heat treatment, and vitrifying the quartz glass base plate by using high-temperature flame with the temperature of more than 1600 ℃ to obtain the high-temperature-resistant shading quartz glass plate after the temperature is increased to 900 ℃.

2. The method as claimed in claim 1, wherein the sintering temperature in step S1 is 900-1200 ℃.

3. The method for producing a silica glass plate for high temperature resistance and shading according to claim 1, wherein the catalyst in step S2 is hydrochloric acid.

4. The method for producing a quartz glass plate for high temperature resistance and shading as claimed in claim 3, wherein the amount ratio of ethyl orthosilicate, absolute ethyl alcohol, distilled water, hydrochloric acid and ammonia water in the step S2 is (0.8-1.2): (4-8): (6-10): (0.03-0.07): (0.02-0.06).

5. The method for producing a silica glass plate for high temperature resistance and shading as claimed in claim 4, wherein the amount ratio of the tetraethoxysilane, the absolute ethyl alcohol, the distilled water, the hydrochloric acid and the ammonia water in the step S2 is 1: 6: 8: 0.05: 0.04.

6. The method for producing a silica glass plate for high temperature resistance and light shielding according to claim 1, wherein formamide is added to the mixed solution in step s2, and the amount of formamide is 10-15% of the amount of tetraethoxysilane.

7. The method for producing a silica glass plate for high temperature resistance and shading according to claim 1, wherein the temperature in the incubator in the step S2 is 60 to 70 ℃.

8. The method of claim 1, wherein in step S3, one-half to four-fifths of the gel is poured into the mold and the rest is poured.

9. The method for producing the quartz glass plate for high temperature resistance and light shielding as claimed in claim 8, wherein the base plate is slowly heated in step S4 at a speed of 2 ℃/min when the temperature is lower than 150 ℃, at a speed of 2 ℃/min when the temperature is 160 ℃ for 150-.

10. The method as claimed in claim 9, wherein the base plate is vitrified in step S4 by using 1600-1750 ℃ high temperature flame.

Technical Field

The invention belongs to the technical field of glass plates, and particularly relates to a production method of a high-temperature-resistant shading quartz glass plate.

Background

The quartz glass is prepared by melting a silicon dioxide raw material with the purity of more than 99.99 percent at the high temperature of more than 1713 ℃, and has the advantages of high temperature resistance, high pressure resistance, corrosion resistance, low expansion coefficient, good thermal shock resistance and the like which cannot be compared with other glasses. Quartz glass has become an important material of modern science and technology due to its specific physical and chemical propertiesIn particular, the material is more and more widely applied to the fields of semiconductors, optical communication, photovoltaics, aerospace, military, integrated circuits, metallurgy, chemical engineering and the like. The application range is extremely wide, and the range is as small as that of daily life and as large as that of aerospace and national defense, and the application range is ubiquitous. The quartz glass plate for high temperature resistance and shading is a novel quartz glass plate applied to a large-scale high-temperature furnace in recent years, has double effects of high temperature resistance and shading, and cannot meet the requirements of the existing quartz glass products. The quartz glass is made of natural quartz as raw material through high-temperature melting and SiO₂High content of industrial glass. The quartz glass is divided into quartz tubes, quartz rods, quartz crucibles, quartz glass blocks and sheets, plates, quartz ingots, quartz bricks, quartz vessels, opaque quartz glass, opal quartz glass, quartz glass ceramics and the like according to the products; the method can be divided into a resistance high temperature method, a resistance vacuum method, a resistance continuous melting method, an electric melting two-step method, an oxyhydrogen flame method, a plasma method, an electric arc method, a chemical synthesis method and the like according to the process. The physical and chemical properties of the quartz glass produced by these processes are substantially identical. The quartz glass plate for high temperature resistance and shading requires that the quartz glass plate not only has no deformation when used at high temperature, but also has the shading function. The opaque quartz glass, the opal quartz glass, the quartz glass ceramic and the like which can be produced at present have slight shading effect but insufficient high temperature resistance and shading effect, the opal quartz glass has good shading effect but insufficient high temperature resistance, and the quartz ceramic glass has good shading effect but poor high temperature resistance and cannot meet the dual requirements of high temperature resistance and shading. Therefore, the existing quartz glass production process cannot meet the production requirements of the quartz glass plate. The quartz glass plate meeting the requirements of high temperature resistance and light shielding needs to have two conditions, namely high temperature resistance and light shielding. The high temperature resistance can be high-purity transparent quartz glass, and the shading can be opaque quartz glass and opal quartz glass. In particular, the physical properties of quartz glass determine that quartz glass is difficult to melt, and the existing production process cannot meet two requirements and can not be completed in one production process. The quartz glass plates used for high-temperature resistance and shading are mostly manufactured by high-temperature splicing, so that the production cost is high and the manufacturing difficulty is high.

Chinese patent document "method for producing silica glass and silica glass (patent No.: ZL201610809509. X)" discloses that the method for producing silica glass comprises: dissolving and mixing a first doping compound and a second doping compound through a dissolving agent to form a doping mixed solution, wherein the first doping compound is an aluminum-containing compound, and the second doping compound comprises at least one of a Zr-containing compound, a Y-containing compound, a Sc-containing compound, a Th-containing compound, a V-containing compound and a Ti-containing compound; and mixing the doping mixed solution with the volume portion of L1 and the water with the volume portion of L2, and reacting with silicon tetrachloride liquid phase to obtain the doped silica gel. In the finished product of the quartz glass of the invention, Al₂O₃、ZrO₂、Y₂O₃Etc. are filled in SiO in the form of network intermediate or network outer body₂The quartz glass of the invention is more compact in the pores of the tetrahedral network structure; at the same time, Al₂O₃、ZrO₂Decomposition energy to cost ratio of SiO₂High, i.e. SiO relative to₂The resistance to hydrofluoric acid is strong, but there is still a problem that the density and strength of the silica glass are to be improved.

Disclosure of Invention

The invention aims to provide a production method of a high-temperature-resistant shading quartz glass plate, which aims to solve the problems of how to optimize components, dosage, process and the like and improve the density and strength of quartz glass on the basis of the disclosure of a preparation method of quartz glass and the quartz glass (with the patent number of ZL201610809509.X) in Chinese patent literature.

In order to solve the technical problems, the invention adopts the following technical scheme:

a production method of a high-temperature-resistant shading quartz glass plate comprises the following steps:

s1: mixing graphite powder and amorphous silicon dioxide powder in a volume ratio of (1-2) to (1.5-2.5), molding the mixed powder, heating at a temperature at which the graphite powder disappears to remove the graphite powder, grinding the silicon dioxide powder into micro-powder slurry with the particle size of 0-150 microns by using a non-metal medium ball mill, casting the micro-powder slurry in a mold for molding, and sintering until air holes contained in a sintered body become closed holes, thereby obtaining opaque quartz glass;

s2: adding tetraethoxysilane, absolute ethyl alcohol and distilled water into a container, uniformly stirring, adding a catalyst into the mixed solution under the state of constant-temperature water bath at 45-55 ℃, continuously stirring until the solution becomes clear, then adding ammonia water into the mixed solution, continuously stirring until sol appears, then stopping stirring, pouring the sol into a mold, and drying the sol in a constant-temperature box to obtain gel;

s3: pouring a part of the gel obtained in the step S2 into a mold, and putting the opaque quartz glass obtained in the step S1 onto the gel, and pouring the other part of the gel to obtain a base plate;

s4: and slowly heating the base plate for heat treatment, and vitrifying the quartz glass base plate by using high-temperature flame with the temperature of more than 1600 ℃ to obtain the high-temperature-resistant shading quartz glass plate after the temperature is increased to 900 ℃.

Preferably, the sintering temperature in the step S1 is 900-1200 ℃.

Preferably, the catalyst in step S2 is hydrochloric acid.

Preferably, the dosage ratio of the ethyl orthosilicate, the absolute ethyl alcohol, the distilled water, the hydrochloric acid and the ammonia water in the step S2 is (0.8-1.2) to (4-8) to (6-10) to (0.03-0.07) to (0.02-0.06).

Preferably, the dosage ratio of the ethyl orthosilicate, the absolute ethyl alcohol, the distilled water, the hydrochloric acid and the ammonia water in the step S2 is 1: 6: 8: 0.05: 0.04.

Preferably, formamide is added to the mixed solution in the step S2, wherein the amount of the formamide is 10-15% of that of the tetraethoxysilane.

Preferably, the temperature in the thermostat in the step S2 is 60-70 ℃.

Preferably, in step S3, one half to four fifths of the gel is poured into the mold, and then the rest is poured.

Preferably, in the step S4, the base plate is slowly heated up at a speed of 2 ℃/min when the temperature is lower than 150 ℃, and is heated up at a speed of 2 ℃/min when the temperature is 150-.

Preferably, the base plate in the step S4 is vitrified by using a high-temperature flame at 1600-.

The invention has the following beneficial effects:

(1) the hydrochloric acid, the ammonia water and the formamide are added in the preparation process of the quartz glass, so that the synergistic effect is achieved, and the density and the strength of the quartz glass are synergistically improved, because: in the preparation of silica gel, ethyl orthosilicate is subjected to hydrolysis reaction and polycondensation reaction, hydrochloric acid is used as a catalyst for the hydrolysis reaction, and H in the hydrochloric acid⁺So that the particle surface of the sol can adsorb a certain amount of H⁺And generates Si-OH with three coordination by molecular vibration and chemical bond breakage, OH in ammonia water^-It is possible to produce SiO with three coordination by vibration and chemical bond cleavage^-，SiO^-Attack Si atoms in the center of other sol molecules and further generate polycondensation reaction. The condensation reaction can promote the gel particles to form a relatively thick interface after the gel is formed, so that the bonding force among the gel particles is enhanced, and the density and the strength of the quartz glass are improved.

Formamide can change the structure of the gel, so that the gel has a narrow-distribution large-aperture structure, the organic solvent in the gel is volatilized from dispersed holes, and the action of capillary force is weakened. Formamide can also interact with Si-OH to form hydrogen bonds, and the hydrogen bonds can effectively prevent the interaction between water molecules and silicon hydroxyl groups and reduce the surface tension. After formamide is added, the precursor generated by the system is oligomer with less than 6 silicon atoms, and based on the oligomer, the polycondensation reaction is further carried out, so that the crosslinking degree of the system is increased, and SiO is promoted₂The network structure of (2) tends to be in a vitrification state, and the density and the strength of the system are improved.

Under the mutual matching of hydrochloric acid, ammonia water and formamide, the density and strength of the quartz glass are synergistically improved.

(2) In the patent document cited in the background of the invention, "method for producing silica glass and silica glass (patent No. ZL201610809509. X)", although Al is contained in the finished silica glass of the invention₂O₃、ZrO₂、Y₂O₃Etc. are filled in SiO in the form of network intermediate or network outer body₂The quartz glass of the invention is more compact in the pores of the tetrahedral network structure; at the same time, Al₂O₃、ZrO₂Decomposition energy to cost ratio of SiO₂High, i.e. SiO relative to₂The hydrofluoric acid resistant quartz glass has strong corrosion resistance, but the density and the strength of the quartz glass still have the problem to be improved, the process is further optimized and improved only by the invention to solve the technical problems, and multiple experimental researches show that in the preparation process, hydrochloric acid, ammonia water and formamide are added as catalysts of hydrolysis reaction, and H in the hydrochloric acid is added as a catalyst of hydrolysis reaction⁺So that the particle surface of the sol can adsorb a certain amount of H⁺And generates Si-OH with three coordination by molecular vibration and chemical bond breakage, OH in ammonia water^-It is possible to produce SiO with three coordination by vibration and chemical bond cleavage^-，SiO^-Attack Si atoms of other sol molecule centers and further carry out polycondensation reaction; after formamide is added, the precursor generated by the system is oligomer with less than 6 silicon atoms, and based on the oligomer, the polycondensation reaction is further carried out, so that the crosslinking degree of the system is increased, and SiO is promoted₂The network structure tends to a vitrification state, thereby achieving the purpose of improving the density and the strength of the system, solving the technical problems appearing in the background technical document and generating unexpected effects.

Detailed Description

For a better understanding of the present invention, the following examples are given to illustrate, but not to limit the scope of the present invention.

The production method of the high-temperature-resistant shading quartz glass plate in the following embodiment comprises the following steps:

s1: mixing graphite powder and amorphous silicon dioxide powder in a volume ratio of (1-2) to (1.5-2.5), molding the mixed powder, heating at a temperature at which the graphite powder disappears to remove the graphite powder, grinding the silicon dioxide powder into micro-powder slurry with the particle size of 0-150 microns by using a non-metal medium ball mill, casting and molding the micro-powder slurry in a mold, and sintering at the temperature of 900-1200 ℃ until pores contained in a sintered body become closed pores, thereby obtaining opaque quartz glass;

s2: adding tetraethoxysilane, absolute ethyl alcohol and distilled water into a container, uniformly stirring, adding hydrochloric acid into a mixed solution in a constant-temperature water bath state at 45-55 ℃, continuously stirring until the solution becomes clear, adding formamide into the mixed solution, wherein the dosage of the formamide is 10-15% of that of the tetraethoxysilane, then adding ammonia water into the mixed solution, continuously stirring until sol appears, then stopping stirring, pouring the sol into a mold, and drying the sol in a constant-temperature box at 60-70 ℃ to obtain gel; the dosage ratio of the ethyl orthosilicate, the absolute ethyl alcohol, the distilled water, the hydrochloric acid and the ammonia water is (0.8-1.2): (4-8): (6-10): (0.03-0.07): (0.02-0.06);

s3, pouring one half to four fifths of the gel in the step S2 into a mold, putting the opaque quartz glass in the step S1 onto the gel, and pouring the rest to obtain a base plate;

s4: and (2) slowly heating the base plate for heat treatment, namely heating at the speed of 2 ℃/min when the temperature is lower than 150 ℃, keeping the temperature at 160 ℃ for 2-3h when the temperature is 150-.

Example 1

A production method of a high-temperature-resistant shading quartz glass plate comprises the following steps:

s1: mixing graphite powder and amorphous silicon dioxide powder in a volume ratio of 1.5: 1.9, forming the mixed powder, heating at a temperature at which the graphite powder disappears to remove the graphite powder, grinding the silicon dioxide powder into micropowder slurry with the particle size of 10 microns by using a non-metal medium ball mill, casting and forming the micropowder slurry in a mould, and sintering at the temperature of 1000 ℃ until pores contained in a sintered body become closed pores, thereby obtaining opaque quartz glass;

s2: adding tetraethoxysilane, absolute ethyl alcohol and distilled water into a container, uniformly stirring, adding hydrochloric acid into the mixed solution in a constant-temperature water bath state at 50 ℃, continuously stirring until the solution becomes clear, adding formamide into the mixed solution, wherein the dosage of the formamide is 11% of that of the tetraethoxysilane, then adding ammonia water into the mixed solution, continuously stirring until sol appears, then stopping stirring, pouring the sol into a mold, and drying the sol in a constant-temperature box at the temperature of 65 ℃ to obtain gel; the dosage ratio of the ethyl orthosilicate, the absolute ethyl alcohol, the distilled water, the hydrochloric acid and the ammonia water is 1: 6: 8: 0.05: 0.04;

s3: pouring a part of three fifths of the gel obtained in the step S2 into a mold, putting the opaque quartz glass obtained in the step S1 into the gel, and pouring the rest to obtain a base plate;

s4: and (3) slowly heating the base plate for heat treatment, namely heating at the speed of 2 ℃/min when the temperature is lower than 150 ℃, keeping the temperature at 160 ℃ for 2h when the temperature is 150-.

Example 2

A production method of a high-temperature-resistant shading quartz glass plate comprises the following steps:

s1: mixing graphite powder and amorphous silicon dioxide powder in a volume ratio of 1.4: 1.5, molding the mixed powder, heating at a temperature at which the graphite powder disappears to remove the graphite powder, grinding the silicon dioxide powder into micro powder slurry with the particle size of 150 microns by using a non-metal medium ball mill, casting and molding the micro powder slurry in a mold, and sintering at the temperature of 1100 ℃ until pores contained in a sintered body become closed pores, thereby obtaining opaque quartz glass;

s2: adding tetraethoxysilane, absolute ethyl alcohol and distilled water into a container, uniformly stirring, adding hydrochloric acid into the mixed solution in a constant-temperature water bath state at 45 ℃, continuously stirring until the solution becomes clear, adding formamide into the mixed solution, wherein the dosage of the formamide is 15% of that of the tetraethoxysilane, then adding ammonia water into the mixed solution, continuously stirring until sol appears, then stopping stirring, pouring the sol into a mold, and drying the sol in a constant-temperature box at 60 ℃ to obtain gel; the dosage ratio of the ethyl orthosilicate, the absolute ethyl alcohol, the distilled water, the hydrochloric acid and the ammonia water is 1: 4: 10: 0.05: 0.06;

s3: pouring a part of the gel of which the part is four fifths of the gel in the step S2 into a mould, putting the opaque quartz glass in the step S1 onto the gel, and pouring the rest to obtain a base plate;

s4: and (3) slowly heating the base plate for heat treatment, namely heating at the speed of 2 ℃/min when the temperature is lower than 150 ℃, keeping the temperature at 160 ℃ for 3h when the temperature is 150-.

Example 3

A production method of a high-temperature-resistant shading quartz glass plate comprises the following steps:

s1: mixing graphite powder and amorphous silicon dioxide powder in a volume ratio of 2: 2.2, forming the mixed powder, heating at a temperature at which the graphite powder disappears to remove the graphite powder, grinding the silicon dioxide powder into micro powder slurry with the particle size of 1 micron by using a non-metal medium ball mill, casting and forming the micro powder slurry in a mould, and sintering at the temperature of 1200 ℃ until air holes contained in a sintered body become closed holes, thereby obtaining opaque quartz glass;

s2: adding tetraethoxysilane, absolute ethyl alcohol and distilled water into a container, uniformly stirring, adding hydrochloric acid into the mixed solution in a constant-temperature water bath state at 50 ℃, continuously stirring until the solution becomes clear, adding formamide into the mixed solution, wherein the dosage of the formamide is 10% of that of the tetraethoxysilane, then adding ammonia water into the mixed solution, continuously stirring until sol appears, then stopping stirring, pouring the sol into a mold, and drying the sol in a constant-temperature box at the temperature of 65 ℃ to obtain gel; the dosage ratio of the ethyl orthosilicate, the absolute ethyl alcohol, the distilled water, the hydrochloric acid and the ammonia water is 1.2: 6: 0.07: 0.02;

s3: pouring a part of the half of the gel obtained in the step S2 into a mold, putting the opaque quartz glass obtained in the step S1 onto the gel, and pouring the rest to obtain a base plate;

s4: and (3) slowly heating the base plate for heat treatment, namely heating at the speed of 2 ℃/min when the temperature is lower than 150 ℃, keeping the temperature at 160 ℃ for 2h when the temperature is 150-.

Example 4

A production method of a high-temperature-resistant shading quartz glass plate comprises the following steps:

s1: mixing graphite powder and amorphous silicon dioxide powder in a volume ratio of 1: 2.5, molding the mixed powder, heating at a temperature at which the graphite powder disappears to remove the graphite powder, grinding the silicon dioxide powder into micro powder slurry with the particle size of 100 microns by using a non-metal medium ball mill, casting and molding the micro powder slurry in a mold, and sintering at the temperature of 900 ℃ until air holes contained in a sintered body become closed holes, thereby obtaining opaque quartz glass;

s2: adding tetraethoxysilane, absolute ethyl alcohol and distilled water into a container, uniformly stirring, adding hydrochloric acid into the mixed solution in a constant-temperature water bath state at 55 ℃, continuously stirring until the solution becomes clear, adding formamide into the mixed solution, wherein the dosage of the formamide is 12% of that of the tetraethoxysilane, then adding ammonia water into the mixed solution, continuously stirring until sol appears, then stopping stirring, pouring the sol into a mold, and drying the sol in a constant-temperature box at 70 ℃ to obtain gel; the dosage ratio of the ethyl orthosilicate, the absolute ethyl alcohol, the distilled water, the hydrochloric acid and the ammonia water is 0.8: 8: 0.03: 0.04;

s3: pouring a part of three fifths of the gel obtained in the step S2 into a mold, putting the opaque quartz glass obtained in the step S1 into the gel, and pouring the rest to obtain a base plate;

s4: and (2) slowly heating the base plate for heat treatment, namely heating at the speed of 2 ℃/min when the temperature is lower than 150 ℃, keeping the temperature at 160 ℃ for 2.5h when the temperature is 150-.

Comparative example 1

The process is substantially the same as in example 1 except that hydrochloric acid, ammonia water, and formamide are not added in the process for producing the high-temperature-resistant and light-shielding quartz glass plate.

Comparative example 2

The process was substantially the same as in example 1, except that hydrochloric acid was not added in the process for producing the high-temperature-resistant, light-shielding quartz glass plate.

Comparative example 3

The process was substantially the same as in example 1, except that ammonia was not added in the process for producing the high-temperature-resistant, light-shielding quartz glass plate.

Comparative example 4

Substantially the same as in example 1 except that formamide was not added in the process for producing the high-temperature-resistant, light-shielding quartz glass plate.

Comparative example 5

The method described in example 1 of the Chinese patent document "method for producing silica glass and silica glass (patent No. ZL201610809509. X)" was used.

According to the quartz glass obtained in the examples 1-4 and the comparative examples 1-5, firstly, compacting and sealing the base materials, then, spreading strains, arranging air holes with the diameter of 1cm in the center of each strain-carrying bag after filling, and transferring the strain-carrying bag into a strain shed to stack and grow strains to produce mushrooms; managing and fruiting according to the conventional technical requirements of the cultivated varieties in the mushroom production stage; after 3 tides of the pleurotus eryngii are produced, fertilizer is supplemented, 300g of urea, 200g of glucose and 120g of fulvic acid salt are added into 50Kg of water, 130g of fertilizer water is injected into each fungus bag, the growth state of the pleurotus eryngii is recorded, and the results are shown in the following table.

Item	Density (g/cm)3)	Strength (MPa)
			Example 1	2.3	3.5
Example 2	2.2	3.4
			Example 3	2.2	3.3
Example 4	2.3	3.4
			Comparative example 1	1.2	2.1
Comparative example 2	2.1	3.2
			Comparative example 3	2.0	3.1
Comparative example 4	2.0	3.2
			Comparative example 5	1.1	1.9

From the above table, it can be seen that: (1) as can be seen from the data of examples 1 to 4 and comparative example 5, the density and strength of the silica glass produced in examples 1 to 4 were significantly higher than those of the silica glass produced in comparative example 5, highlighting a significant advance in the art, and example 1 was the most preferable example.

(2) As can be seen from the data of example 1 and comparative examples 1 to 4, the addition of hydrochloric acid, ammonia, and formamide during the preparation of the silica glass provides a synergistic effect, which synergistically increases the density and strength of the silica glass because: in the preparation of silica gel, ethyl orthosilicate is subjected to hydrolysis reaction and polycondensation reaction, hydrochloric acid is used as a catalyst for the hydrolysis reaction, and H in the hydrochloric acid⁺So that the particle surface of the sol can adsorb a certain amount of H⁺And generates Si-OH with three coordination by molecular vibration and chemical bond breakage, OH in ammonia water^-Can be generated by vibration and chemical bond breakageSiO with three coordination^-，SiO^-Attack Si atoms in the center of other sol molecules and further generate polycondensation reaction. The condensation reaction can promote the gel particles to form a relatively thick interface after the gel is formed, so that the bonding force among the gel particles is enhanced, and the density and the strength of the quartz glass are improved.

Formamide can change the structure of the gel, so that the gel has a narrow-distribution large-aperture structure, the organic solvent in the gel is volatilized from dispersed holes, and the action of capillary force is weakened. Formamide can also interact with Si-OH to form hydrogen bonds, and the hydrogen bonds can effectively prevent the interaction between water molecules and silicon hydroxyl groups and reduce the surface tension. After formamide is added, the precursor generated by the system is oligomer with less than 6 silicon atoms, and based on the oligomer, the polycondensation reaction is further carried out, so that the crosslinking degree of the system is increased, and SiO is promoted₂The network structure of (2) tends to be in a vitrification state, and the density and the strength of the system are improved.

Under the mutual matching of hydrochloric acid, ammonia water and formamide, the density and strength of the quartz glass are synergistically improved.

The above description should not be taken as limiting the invention to the embodiments, but rather, as will be apparent to those skilled in the art to which the invention pertains, numerous simplifications or substitutions may be made without departing from the spirit of the invention, which shall be deemed to fall within the scope of the invention as defined by the claims appended hereto.