A nano-silicon-based heat-insulating and fireproof glass film and its preparation method

Abstract

The present invention relates to the technical field of fireproof glass, and particularly to a nano-silicon-based heat-insulating fireproof glass film and a preparation method thereof. The film includes a film base layer, a sound insulation layer, and a flame retardant layer sequentially disposed on the film base layer. The film base layer comprises the following components in parts by weight: 10-30 parts of nano-silica, 50-70 parts of matrix resin, 1-3 parts of dispersant, 1-3 parts of stabilizer, 1-3 parts of cross-linking agent, 5-10 parts of plasticizer, and 10-32 parts of solvent. This glass film has good heat insulation, fire resistance and high temperature resistance, can effectively isolate the fire source and prevent the spread of fire, and has good tensile property and mechanical strength, avoiding problems such as fracture during use. Moreover, the film is colorless and transparent with high light transmittance.

Description

Technical Field

[0001] The present invention relates to the technical field of fireproof glass, and particularly to a nano-silicon-based heat-insulating fireproof glass film and a preparation method thereof. Background Art

[0002] Laminated composite glass is a composite glass product formed by two or more pieces of glass with one or more layers of organic polymer interlayers sandwiched between them. After special high-temperature pre-pressing (or vacuum pumping) and high-temperature and high-pressure process treatment, the glass and the interlayer are permanently bonded together. Commonly used interlayers for laminated glass include: PVB, SGP, EVA, PU, etc.

[0003] Chinese Patent with Application No. CN110605885B discloses a laminated composite glass with a multi-layer structure, including a first inner-layer glass and a second inner-layer glass. There is a vacuum layer between the first inner-layer glass and the second inner-layer glass. A first inner-layer film is provided on one side of the first inner-layer glass, a transparent conductive film is provided on one side of the first inner-layer film, an indoor glass is provided on one side of the transparent conductive film, a transparent conductive film is provided on one side of the indoor glass, a second inner-layer film is provided on one side of the second inner-layer glass, a photoelectric glass is provided on one side of the second inner-layer film, an outdoor glass is provided on one side of the photoelectric glass, and a hollow layer is provided between the outdoor glass and the photoelectric glass. Through the multi-layer structure design, the laminated composite glass can generate electricity and defog by using the structure design of the transparent conductive film and the photoelectric glass. By using the design of the hollow layer and the vacuum layer, the heat insulation and sound insulation effects of the laminated composite glass are improved. Chinese Patent Document with Application No. CN202411695392.8 discloses an SGP film laminated glass and its production process. By mixing and extruding a modified resin and an SGP laminated resin to form a film, a laminated film is obtained. The laminated film is placed between two pieces of glass and hot-pressed at high temperature. When the modified resin and the SGP laminated resin are melted, the double bonds on the modified resin can graft with the molecular chains on the SGP laminated resin. The main body of the modified resin molecular chain is a polyurethane structure containing an organosilicon segment, which can improve the heat insulation effect of the SGP laminated resin. Moreover, the modified filler contains a multi-void structure, further enhancing the heat insulation effect. Additionally, the titanium-containing organosilicon resin segment in the modified resin, the tin dioxide on the surface of the modified filler, and the benzotriazole structure in the modified resin can increase the absorption of ultraviolet rays by the laminated film and reduce the ultraviolet radiation.

[0004] Using a single resin as the film matrix, its heat insulation performance, mechanical properties, etc. cannot meet the requirements. Nano-silica can well improve the above properties. However, due to van der Waals forces, nano-silica particles are prone to agglomeration, resulting in poor fluidity of the solution and uneven coating thickness, seriously affecting the heat insulation performance and transparency. In practical applications, this agglomeration phenomenon will lead to poor local heat insulation effect of the film, and even hot spots may appear, affecting the overall performance of the fireproof glass. In addition, the agglomerated nano-silica particles will also affect the transparency of the film, reducing the daylighting effect of the glass. During long-term storage or transportation, nano-silica particles are prone to sedimentation or gelation, resulting in poor product performance consistency. Sedimentation will cause uneven distribution of nano-silica particles in the film, affecting the heat insulation performance and mechanical strength. Gelation will make the film hard and brittle, reducing its flexibility and processing performance, and may even cause cracking and other phenomena during the use of the film. In the light and humid environment, traditional products are prone to yellowing, blistering, and fogging, affecting the appearance and use performance. Yellowing will cause a decrease in the transparency of the film, affecting the daylighting effect of the glass. Blistering and fogging will cause defects on the surface of the film, reducing its mechanical strength and heat insulation performance, and may even cause peeling and other phenomena during the use of the film.

[0005] At present, there is an urgent need for a new type of nano-silica film with high dispersibility, high stability, good equipment compatibility and low cost, as well as a preparation method, to solve the problems of yellowing, blistering, fogging, poor fireproof stability of existing products, and optical deformation caused by fluidity when used with glass. Specifically, a nano-silica film that can be industrially produced on existing production equipment is needed, which should have good dispersibility and stability, be able to maintain stable performance in the light and humid environment, have a long fire resistance limit and a low thermal conductivity, and avoid optical deformation caused by fluidity when used with glass. Summary of the Invention

[0006] To solve the above problems, the present invention provides a nano-silicon-based heat-insulating and fireproof glass film and a preparation method thereof. The glass film has good heat insulation, fire resistance and high-temperature resistance, can effectively isolate the fire source and prevent the spread of fire, and has good tensile strength and mechanical strength, avoiding problems such as fracture during use. And the film is colorless and transparent with high light transmittance.

[0007] The technical solutions adopted by the present invention to achieve the above purpose are as follows:

[0008] A nano-silicon-based heat-insulating and fireproof glass film, comprising a film base layer, a sound-insulating layer and a flame-retardant layer sequentially arranged on the film base layer. The film base layer comprises the following components in parts by weight: 10-30 parts of nano-silica, 50-70 parts of matrix resin, 1-3 parts of dispersant, 1-3 parts of stabilizer, 1-3 parts of cross-linking agent, 5-10 parts of plasticizer, and 10-32 parts of solvent. The matrix resin is modified polyvinyl alcohol or polyurethane. The preparation method of the modified polyvinyl alcohol is as follows:

[0009] Step S1, dissolve polyvinyl alcohol in water, add polyethylene glycol diglycidyl ether as a cross-linking agent, and react at 50-60 °C for 2-4 hours under alkaline conditions. After dialysis purification and drying, cross-linked polyvinyl alcohol resin is obtained;

[0010] Step S2, disperse the cross-linked polyvinyl alcohol resin obtained in Step S1 in a mixed solvent of N, N-dimethylformamide and water, add maleic acid and a radical initiator, and react at 90-100 °C for 4-6 hours under nitrogen protection. Then, carry out precipitation, centrifugation and drying to obtain graft-modified polyvinyl alcohol resin;

[0011] Step S3, mechanically blend and compound nano-cellulose with the graft-modified polyvinyl alcohol resin obtained in Step S2 to obtain the product.

[0012] Further, in Step S1, the addition amount of polyethylene glycol diglycidyl ether is 5-15% of the mass of polyvinyl alcohol; the weight-to-volume ratio of polyvinyl alcohol to water is 8-12 g: 100 ml.

[0013] Further, in Step S1, the pH of the alkaline condition is 10-11, which is adjusted by sodium hydroxide; dialysis purification is carried out using a dialysis bag with a cut-off molecular weight of 8000-14000 for 48-72 hours.

[0014] Further, in Step S2, the addition amount of maleic acid is 8-20% of the mass of the cross-linked polyvinyl alcohol obtained in Step S1; the radical initiator is potassium persulfate, and the addition amount is 2-3% of the mass of maleic acid; the weight-to-volume ratio of the cross-linked polyvinyl alcohol obtained in Step 1 to the mixed solvent is: 5-10 g: 100 ml, and the weight ratio of N, N-dimethylformamide to water in the mixed solvent is 4: 0.8-1.2.

[0015] Further, in Step S3, the addition amount of nano-cellulose is 5-15% of the mass of the graft-modified polyvinyl alcohol resin obtained in Step S2.

[0016] For the modification of polyvinyl alcohol above, polyethylene glycol diglycidyl ether (PEGDE) is used as a flexible cross-linking agent. Under alkaline conditions, it reacts with the hydroxyl groups of PVA to form a three-dimensional cross-linked network. The high cross-linking degree endows excellent thermal stability and mechanical strength. The appropriate dosage of polyethylene glycol diglycidyl ether can ensure the denseness of the network and avoid the brittleness caused by excessive cross-linking. The cross-linked polyvinyl alcohol resin has a higher thermal decomposition temperature and can remain stable in a high-temperature environment. The cross-linked structure can effectively prevent the hydrolysis and degradation of polyvinyl alcohol in a chemical environment and improve its chemical stability. In step S2, polar carboxyl functional groups are introduced onto the polyvinyl alcohol molecular chain by maleic acid. These functional groups can form hydrogen bonds and other interactions between the polyvinyl alcohol molecular chains, enhancing the binding force between the molecular chains, thereby improving the mechanical properties such as the tensile strength and modulus of the material. The grafting of maleic acid can improve the thermal stability of polyvinyl alcohol, increase its decomposition temperature at high temperatures, reduce the generation of thermal decomposition products, and thus extend the service life of the material. The polyvinyl alcohol modified by maleic acid grafting has better polarity and can have better compatibility with a variety of other materials (such as inorganic fillers, other polymers, etc.), which is beneficial to the preparation of composite materials with excellent properties. The bonding performance between the grafted polyvinyl alcohol resin and the glass surface is significantly improved. This is because the carboxyl functional groups introduced by maleic acid grafting can undergo chemical bonding or hydrogen bonding with the hydroxyl groups on the glass surface, thereby enhancing the bonding strength between the film and the glass. The water resistance of the modified polyvinyl alcohol resin is improved, and even in a humid environment, its bonding performance with the glass can remain stable and is not easily reduced due to the penetration of water molecules.

[0017] The stability of the polyvinyl alcohol resin modified by adding maleic acid is enhanced under environmental factors such as ultraviolet irradiation and temperature changes, and the weather resistance of the glass film is improved, enabling it to better adapt to different environmental conditions.

[0018] Nanocellulose has high strength and high modulus. When it is uniformly dispersed in the resin matrix, it can effectively enhance the tensile strength and impact resistance of the composite material. Nanocellulose itself has good thermal stability, and its combination with polyvinyl alcohol further improves the heat resistance of the composite material. Crosslinked polyvinyl alcohol itself has certain flame retardant properties. The composite structure of crosslinked polyvinyl alcohol and nanocellulose can form a stable char layer at high temperatures, effectively preventing the transfer of heat and oxygen, thereby prolonging the fire protection time of the material and further improving the fire protection performance of the composite material. At the same time, the dense filling of nanocellulose reduces the gas permeation path and lowers the oxygen transmission rate, synergistically enhancing the heat insulation and fire protection properties. The addition of nanocellulose not only enhances the strength of the material but also improves the flexibility of the composite material through its unique nanostructure. The mechanical blending and compounding of nanocellulose and modified polyvinyl alcohol enable the two to be uniformly dispersed, forming a good composite structure. At the same time, the composite structure of nanocellulose and nanosilica can effectively block the heat transfer and improve the heat insulation performance of the material. The addition of nanocellulose further enhances the sound insulation effect of the composite material, and the composite structure of nanocellulose and nanosilica can improve the optical properties of the material, such as transparency and light scattering properties.

[0019] The surface hydroxyl groups of modified polyvinyl alcohol and nano-SiO2 are bonded through hydrogen bonds or esterification reactions to form a strong "resin-filler" interfacial layer, reducing stress concentration and improving mechanical properties. The multi-scale pores of the nano-SiO2 structure and nanocellulose act synergistically to inhibit heat conduction, reduce the thermal conductivity, and improve the heat insulation performance. The crosslinked network of modified polyvinyl alcohol carbonizes at high temperatures to form a dense char layer. Nano-SiO2 and nanocellulose act as inorganic barriers to inhibit the diffusion of combustible gases, and their synergistic effect further improves the flame retardant performance.

[0020] Furthermore, in the step S3, the nanocellulose is first pretreated with a silane coupling agent KH-550.

[0021] Furthermore, the pretreatment steps of nanocellulose are as follows: Disperse nanocellulose in deionized water and treat it with an ultrasonic disperser for 25 - 35 minutes to obtain solution 1; Dissolve the silane coupling agent in ethanol, stir evenly, and then add it to solution 1, and stir and react at 60 - 80 °C for 1.5 - 2.5 hours. After the reaction is completed, centrifuge and wash 3 times with ethanol and deionized water, and dry the precipitate to obtain pretreated nanocellulose; Among them, the weight-to-volume ratio of nanocellulose to deionized water is 10 g:90 - 110 ml, the weight-to-volume ratio of the silane coupling agent to ethanol is 2 g:180 - 220 ml, and the dosage ratio of nanocellulose to the silane coupling agent is 10:0.15 - 0.25.

[0022] The nanocellulose was pretreated with silane coupling agent KH-550 to introduce active groups such as amino groups, significantly improving the surface activity of the nanocellulose. The pretreated nanocellulose can be more uniformly dispersed in the polyvinyl alcohol matrix, avoiding agglomeration, thereby improving the overall performance of the composite material. The pretreated nanocellulose can form a stronger interfacial bond with the polyvinyl alcohol matrix, further enhancing the bonding force between the two through hydrogen bonding or esterification reactions. The strong interfacial layer can effectively disperse stress and reduce stress concentration, thus improving the mechanical properties of the composite material. The pretreated nanocellulose can better combine with the polyvinyl alcohol or polyurethane matrix at high temperatures, improving the thermal stability of the composite material. The pretreated nanocellulose can fill more densely in the resin matrix, reducing the gas permeation path and further improving the barrier properties of the composite material. The pretreated nanocellulose can better combine with the resin matrix during mechanical blending, improving the processing performance of the composite material. The uniformly dispersed nanocellulose can improve the molding quality of the composite material, reducing defects and non-uniformities.

[0023] The above-mentioned modified polyvinyl alcohol or polyurethane as the resin matrix has significant advantages in mechanical properties, barrier properties, interfacial bonding, heat insulation properties, and flame retardant properties when compounded with nanosilicon to prepare the film. Pretreating the nanocellulose can further enhance its surface activity, interfacial bonding, and dispersibility, thereby further improving the overall performance of the composite material. These improvements make the composite material have good application prospects in high-performance application fields.

[0024] Furthermore, the dispersant is polyacrylamide, the stabilizer is sodium carboxymethyl cellulose, the crosslinking agent is silane coupling agent, the plasticizer is dibutyl phthalate, and the solvent is absolute ethanol.

[0025] Furthermore, the sound insulation layer is mainly made of thermoplastic polyurethane elastomer rubber and hollow glass microspheres, and the flame retardant layer is mainly made of waterborne acrylic resin and ammonium polyphosphate.

[0026] The preparation method of the above-mentioned nano-silicon-based heat-insulating and fire-proof glass film, wherein the preparation method of the film base layer includes the following steps: nano-silica pretreatment → ultrasonic dispersion → resin dissolution → mixing → filtration and degassing → hot pressing and forming, gradient cooling → crosslinking and curing, polishing.

[0027] Specifically, the steps of the preparation method of the film base layer are as follows:

[0028] Step 1, vacuum dry the nano-silica at 95-105 °C for 1.8-2.2 hours to remove the surface adsorbed water and avoid the influence of moisture on the dispersion effect and product performance; Vacuum drying can effectively remove the adsorbed water on the surface of nano-silica, preventing it from reacting with the solvent during dispersion and affecting the dispersion effect and product performance;

[0029] Step 2: Mix nano-silica and absolute ethanol at a ratio of 1:5 - 10 (weight to volume ratio), then add polyacrylamide (PAM), and magnetically stir at a speed of 450 - 550 rpm for 8 - 12 minutes to preliminarily disperse the nano-silica in ethanol. Then, ultrasonically treat for 30 - 60 minutes under the conditions of a frequency of 30 - 40 kHz and a power of 180 - 220 W, and control the solution temperature at 25 - 30 °C. Preliminary dispersion can reduce the agglomeration phenomenon and create good conditions for subsequent ultrasonic dispersion. The high-frequency vibration of ultrasonic waves further breaks the aggregates of nano-silicon particles to make them evenly dispersed. At the same time, controlling the temperature can prevent the performance of the dispersant and nano-silica from being affected by excessive temperature, and improve the performance and stability of the film.

[0030] Step 3: Filter with a 0.2 μm filter membrane and remove the large undispersed particles in the solution after ultrasonic dispersion in Step 2 under a pressure of 0.2 MPa to ensure the uniformity and stability of the solution and avoid the influence of large particles on the performance and appearance quality of the film.

[0031] Step 4: Add modified polyvinyl alcohol (PVA) or polyurethane (PU) to the solution filtered in Step 3 and stir at 60 - 80 °C until completely dissolved. The appropriate temperature helps the resin dissolve quickly and controls the viscosity for the subsequent mixing of additives.

[0032] Step 5: In the solution obtained in Step 4, sequentially add the stabilizer sodium carboxymethyl cellulose (CMC), the cross-linking agent KH-550, the plasticizer (dibutyl phthalate DBP), and the remaining solvent, and high-speed shear stir at a speed of 1400 - 1600 rpm for 15 - 25 minutes to make each additive evenly dispersed in the solution, fully play their respective roles, and improve the performance and stability of the film. Then, use a 0.2 μm filter membrane again to remove the residual impurities in the reaction solution. Secondary filtration can remove the residual impurities in the solution, further improve the purity of the product, and ensure the performance and appearance quality of the film. After filtration, defoam at a vacuum degree of -0.1 MPa for 12 - 18 minutes to ensure that the residual bubble content ≤ 0.1%, and avoid defects caused by the presence of bubbles during the film forming process. Vacuum defoaming can effectively remove the bubbles in the solution, avoid defects caused by the presence of bubbles during the film forming process, and improve the strength and heat insulation performance of the film.

[0033] Step 6, hot press molding is carried out by using a flat vulcanizing machine under the conditions of 160 - 180 °C and 8 - 10 MPa, and the pressure holding time is 4 - 6 minutes to initially form the film; then, gradient cooling is carried out in the way of 80 °C → 50 °C → room temperature; the hot press process can make the components in the solution fully fuse and react to form a uniform film, improving the performance and strength of the film; gradient cooling can prevent warping and deformation of the film caused by internal stress, ensuring its dimensional stability and appearance quality;

[0034] Step 7, put the cooled film into an oven at 80 - 100 °C for curing for 2.5 - 3.5 hours, and then carry out polishing treatment with a chemical polishing solution with pH = 8 - 9 until the surface roughness Ra ≤ 0.1 μm, thus obtaining; cross - linking and curing can enhance the chemical bond connection inside the film, making the chemical bonds inside the film fully cross - linked, improving the mechanical properties, heat resistance and chemical stability of the film, and enhancing the overall performance of the film; surface polishing can effectively remove the micro - defects on the surface of the film, improve its surface smoothness and optical properties, and enhance the aesthetics and use effect of the film.

[0035] Further, the preparation method of the sound - insulation layer is: thermoplastic polyurethane elastomer rubber and hollow glass microspheres are mixed in a weight ratio of 100:10 - 15, then calendered into a film by an extruder, and then hot - press compounded with the film base layer, with a hot - press temperature of 120 - 130 °C, a pressure of 0.8 MPa, and a time of 30 - 60 seconds;

[0036] Further, the preparation method of the flame - retardant layer is: water - borne acrylic resin ammonium polyphosphate, aluminum hydroxide, acrylic emulsion, and substrate wetting agent TEGO Twin 4100 are mixed evenly and then coated on the sound - insulation layer, and then dried at 75 - 85 °C, where the weight ratio of water - borne acrylic resin ammonium polyphosphate, aluminum hydroxide, acrylic emulsion, and substrate wetting agent TEGO Twin 4100 is 50 - 65:15 - 25:10 - 20:5 - 10:1 - 3.

[0037] The hollow glass microspheres in the sound - insulation layer have low density and high porosity, which can effectively reflect and absorb sound waves and reduce the penetration of sound. This structure enables the sound - insulation layer to have good sound - insulation effects in a relatively wide frequency range. Thermoplastic polyurethane elastomer rubber has good elasticity and flexibility, which can further absorb and disperse sound wave energy and enhance the sound - insulation effect. The addition of thermoplastic polyurethane elastomer rubber makes the sound - insulation layer have good flexibility and impact resistance, and can withstand a certain amount of external force without being easily broken. Thermoplastic polyurethane elastomer rubber has good durability and can maintain stable sound - insulation performance during long - term use. The low density of the hollow glass microspheres enables the sound - insulation layer to achieve lightweight design while maintaining high - efficiency sound - insulation performance, and is suitable for application scenarios with strict weight requirements.

[0038] In the flame retardant layer, ammonium polyphosphate is an efficient intumescent flame retardant. It can decompose to generate phosphoric acid at high temperatures, promoting the formation of a charred layer on the surface of the substrate and preventing the transfer of heat and oxygen. Aluminum hydroxide decomposes to absorb a large amount of heat, reducing the surface temperature of the material and delaying combustion. At the same time, the generated water vapor can dilute the concentration of combustible gases and inhibit the spread of flames. The residual Al2O3 forms a dense heat-insulating layer on the surface of the material, blocking the transfer of oxygen and heat. The acrylic emulsion can form a uniform coating, improving the adhesion and durability of the flame retardant layer. The substrate wetting agent TEGO Twin 4100 can improve the adhesion between the flame retardant layer and the sound insulation layer, ensuring uniform distribution of the coating and enhancing the stability and durability of the flame retardant layer.

[0039] The combination of the sound insulation layer and the flame retardant layer endows the composite material with not only excellent sound insulation performance but also high fire resistance. This multi-functional integrated design enables the material to meet multiple performance requirements simultaneously in various building scenarios. The flexibility of the sound insulation layer and the adhesion of the flame retardant layer work synergistically to further improve the overall mechanical properties of the composite material. For example, the elasticity of thermoplastic polyurethane elastomer rubber can enhance the impact resistance of the flame retardant layer, while the uniform coating of the flame retardant layer can improve the durability of the sound insulation layer. The porous structure of the sound insulation layer can further reduce heat conduction and improve the heat insulation performance of the material, while the charred layer formed by the flame retardant layer at high temperatures can further enhance the heat insulation effect. In case of emergencies such as fires, the addition of the sound insulation layer and the flame retardant layer can further enhance the mechanical properties of the film substrate. The charred layer formed by the flame retardant layer at high temperatures can protect the film substrate from rapid decomposition at high temperatures. This protective effect not only improves the fire resistance of the material but also extends its service life. The synergistic effect of the sound insulation layer and the flame retardant layer can optimize the acoustic and thermal properties of the material. The addition of the sound insulation layer and the flame retardant layer enables the film substrate to have not only excellent heat insulation and fire resistance but also good sound insulation. This multi-functionality gives the material a broader application prospect in various application scenarios.

[0040] The present invention has the following beneficial effects:

[0041] The nano-silicon-based heat insulation and fireproof glass film provided by the present invention has good heat insulation, fire resistance and high temperature resistance performance. It can effectively isolate the fire source and prevent the spread of fire, and can meet different fire resistance time requirements. Among them, the addition of components such as nano-silica can effectively reduce heat radiation and heat transfer, enabling the glass film to maintain good heat insulation performance in high temperature environments. By using matrix resins such as modified polyvinyl alcohol and the strengthening effect of nano-cellulose, the tensile property and mechanical strength of the film are improved, avoiding problems such as fracture during use. Moreover, the film is colorless, transparent and has a high light transmittance.

[0042] Among them, nano-silica has the characteristic of low thermal conductivity. There are void structures inside it, filled with air, effectively blocking heat transfer. Nano-silica has a selective characteristic for the solar spectrum, which can effectively shield infrared thermal radiation, thereby reducing heat absorption. The addition of nano-silica forms a dense thermal barrier, which can reflect or scatter infrared radiation. Combined with the resin matrix, it effectively blocks heat conduction and is suitable for energy-saving building glass. Nano-silica enhances the resin matrix and forms a three-dimensional network structure in combination with a cross-linking agent, improving the tensile strength and impact resistance. The stabilizer prevents the material from aging and extends the service life. The dispersant makes the nano-materials evenly dispersed, reduces light scattering, and maintains high light transmittance. The plasticizer adjusts the flexibility. Each component interacts synergistically to obtain a fireproof glass film with high strength, aging resistance, and good light transmittance.

[0043] Furthermore, the addition of the sound insulation layer and the flame retardant layer significantly improves the performance of the composite material, not only enhancing the sound insulation and fireproof performance of the material, but also strengthening the mechanical properties and thermal stability of the material. This multi-functional integrated design enables the material to have good application prospects in high-performance application fields.

[0044] The preparation method of this film realizes the high performance and process stability control of the nano-composite material through multi-step precise control, solves the defects of uneven dispersion and unstable performance in traditional composite materials, and is especially suitable for application scenarios with strict requirements for optical, mechanical, and heat insulation properties. Specific embodiments

[0045] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0046] The raw materials used in the following embodiments are all ordinary commercially available products. Nano-silica, 15 - 50 nm, Luoyang Tongrun Nano Technology Co., Ltd.; Polyvinyl alcohol, with an effective ingredient content of 99%, Inner Mongolia Meiguan Environmental Protection Products Co., Ltd.; Polyacrylamide, white granular appearance, Renqiu Hengyu Chemical Industry Co., Ltd.; Sodium carboxymethyl cellulose, white or slightly yellow powder, Zibo Daoqin New Materials Co., Ltd.; Polyethylene glycol diglycidyl ether, with an effective ingredient content of 99%, Wuhan Shuer Biotechnology Co., Ltd.; Nano-cellulose, with an effective ingredient content of 99%, Zibo Daoqin New Materials Co., Ltd.; TEGO Twin 4100, Shanghai Zhenli Shi Network Technology Co., Ltd. Example 1

[0047] A nano-silicon-based heat-insulating and fireproof glass film, comprising a film base layer, a sound-insulating layer and a flame-retardant layer sequentially arranged on the film base layer. The film base layer comprises the following components by weight: 20 parts of nano-silica, 60 parts of matrix resin, 2 parts of dispersant, 2 parts of stabilizer, 2 parts of cross-linking agent, 7 parts of plasticizer, and 22 parts of solvent. The matrix resin is modified polyvinyl alcohol, the dispersant is polyacrylamide, the stabilizer is sodium carboxymethyl cellulose, the cross-linking agent is silane coupling agent KH-550, the plasticizer is dibutyl phthalate, and the solvent is absolute ethanol.

[0048] The preparation method of the modified polyvinyl alcohol is as follows:

[0049] Step S1, dissolve polyvinyl alcohol in water, add polyethylene glycol diglycidyl ether (PEGDE) as a cross-linking agent, react at 55 °C for 3 hours under the condition of pH 10 - 11, and obtain cross-linked polyvinyl alcohol resin after dialysis purification and drying; the molecular weight of the polyethylene glycol diglycidyl ether (PEGDE) is 400 - 1000, and the addition amount is 10% of the mass of polyvinyl alcohol; the weight-to-volume ratio of polyvinyl alcohol to water is 10 g:100 ml; the alkaline condition is adjusted by adding a 30% sodium hydroxide solution; dialysis purification is carried out using a dialysis bag with a molecular weight cut-off of 8000 - 14000 for 60 hours; then, under the condition of 55 °C, vacuum drying is carried out for 36 hours;

[0050] Step S2, disperse the cross-linked polyvinyl alcohol resin obtained in step S1 in a mixed solvent of N,N-dimethylformamide and water, add maleic acid and a radical initiator, react at 95 °C for 5 hours under nitrogen protection, cool to room temperature in an ice bath, then drop the reaction solution into 4 times the volume of absolute ethanol of the reaction solution for precipitation, and keep stirring during the precipitation process to avoid agglomeration, then centrifuge at 9000 rpm for 12 minutes, wash once with a mixed solution of ethanol and water with a volume ratio of 3:1 and twice with absolute ethanol, and then keep constant weight at 45 °C in a vacuum drying chamber to obtain graft-modified polyvinyl alcohol resin; the addition amount of maleic acid is 14% of the mass of the cross-linked polyvinyl alcohol in step S1; the radical initiator is potassium persulfate, and the addition amount is 2.5% of the mass of maleic acid; the weight-to-volume ratio of the cross-linked polyvinyl alcohol obtained in step 1 to the mixed solvent is: 7 g:100 ml, and in the mixed solvent, the weight ratio of N,N-dimethylformamide to water is 4:1;

[0051] Step S3, nano-cellulose composite reinforcement: Mix nano-cellulose and the graft-modified polyvinyl alcohol resin obtained in step S2 by mechanical blending to obtain; the mechanical blending is carried out by using a high-speed shear emulsifier at a rotation speed of 10000 rpm for 30 minutes; the addition amount of nano-cellulose is 10% of the mass of the graft-modified polyvinyl alcohol resin in step S2;

[0052] Among them, the nanocellulose is first pretreated with a silane coupling agent KH-550. The specific steps are as follows: Disperse the nanocellulose in deionized water and treat it with an ultrasonic disperser for 30 minutes to obtain Solution 1, where the weight-volume ratio of nanocellulose to deionized water is 10 g: 100 ml; Dissolve the silane coupling agent in ethanol, stir evenly, and then add it to Solution 1 and stir and react at 70 °C for 2 hours, where the weight-volume ratio of the silane coupling agent to ethanol is 2 g: 200 ml, and the dosage ratio of nanocellulose to the silane coupling agent is 10: 0.25; After the reaction, perform centrifugal separation, wash 3 times with ethanol and deionized water, and dry the precipitate to a constant weight to obtain pretreated nanocellulose.

[0053] The preparation method of the above-mentioned nano-silicon-based heat-insulating and fire-proof glass film is as follows:

[0054] Step 1, Vacuum-dry the nano-silica at 100 °C for 2 hours to remove the surface-adsorbed water and avoid the influence of moisture on the dispersion effect and product performance;

[0055] Step 2, Mix the nano-silica and absolute ethanol in a ratio of 1:7 (weight-volume ratio), then add polyacrylamide PAM and magnetically stir at a speed of 500 rpm for 10 minutes to preliminarily disperse the nano-silica in ethanol; Then, perform ultrasonic treatment for 45 minutes under the conditions of a frequency of 35 kHz and a power of 200 W, and control the solution temperature at 27 °C;

[0056] Step 3, Filter with a 0.2-μm filter membrane and under a pressure of 0.2 MPa to remove the large undispersed particles in the solution after ultrasonic dispersion in Step 2, ensure the uniformity and stability of the solution, and avoid the influence of large particles on the performance and appearance quality of the film;

[0057] Step 4, Add the modified polyvinyl alcohol PVA to the solution filtered in Step 3 and stir at 70 °C until completely dissolved. The appropriate temperature helps the resin dissolve quickly and controls the viscosity for the subsequent mixing of additives;

[0058] Step 5, In the solution obtained in Step 4, sequentially add the stabilizer CMC, the cross-linking agent KH-550, the plasticizer (dibutyl phthalate DBP) and the remaining solvent, and perform high-speed shear stirring at a speed of 1500 rpm for 20 minutes; Then, use a 0.2-μm filter membrane again to remove the residual impurities in the reaction solution; After filtration, perform degassing at a vacuum degree of -0.1 MPa for 15 minutes to ensure that the residual bubble content ≤ 0.1%;

[0059] Step 6, Use a flat vulcanizing machine to perform hot pressing and forming at 170 °C and 9 MPa, and the pressure-holding time is 5 minutes. The film is preliminarily formed, and then, perform cooling using a gradient cooling method of 80 °C → 50 °C → room temperature;

[0060] Step 7: Put the cooled film into an oven at 90 °C for curing for 3 hours; then perform polishing treatment with a chemical polishing solution with pH = 8 - 9 until the surface roughness Ra ≤ 0.1 μm to obtain a film substrate;

[0061] Step 8: After mixing thermoplastic polyurethane elastomer rubber and hollow glass microspheres in a weight ratio of 100:12, calender them into a film through an extruder, and then thermally press and laminate them with the film substrate at a thermal pressing temperature of 125 °C, a pressure of 0.8 MPa, and a time of 45 seconds;

[0062] Step 9: Mix ammonium polyphosphate of waterborne acrylic resin, aluminum hydroxide, acrylic emulsion, and substrate wetting agent TEGOTwin 4100 evenly, coat them on the sound insulation layer, and then dry them at 80 °C to obtain. Among them, the weight ratio of ammonium polyphosphate of waterborne acrylic resin, aluminum hydroxide, acrylic emulsion to substrate wetting agent TEGO Twin 4100 is 58:20:10 - 20:5:2. Example 2

[0063] A nano - silicon - based heat - insulating and fire - proof glass film, comprising a film substrate, a sound insulation layer, and a flame - retardant layer sequentially arranged on the film substrate. The film substrate comprises the following components by weight: 10 parts of nano - silicon dioxide, 70 parts of matrix resin, 3 parts of dispersant, 1 part of stabilizer, 3 parts of cross - linker, 10 parts of plasticizer, and 32 parts of solvent. The matrix resin is modified polyvinyl alcohol, the dispersant is polyacrylamide, the stabilizer is sodium carboxymethyl cellulose, the cross - linker is silane coupling agent KH - 550, the plasticizer is dibutyl phthalate, and the solvent is absolute ethanol.

[0064] The preparation method of the modified polyvinyl alcohol is as follows:

[0065] Step S1: Dissolve polyvinyl alcohol in water, add polyethylene glycol diglycidyl ether (PEGDE) as a cross - linker, and react at 50 °C for 4 hours under the condition of pH = 10 - 11. After dialysis purification and drying, cross - linked polyvinyl alcohol resin is obtained; the molecular weight of the polyethylene glycol diglycidyl ether (PEGDE) is 400 - 1000, and the addition amount is 5% of the mass of polyvinyl alcohol; the weight - to - volume ratio of polyvinyl alcohol to water is 8 g:100 ml; the alkaline condition is adjusted by adding a 30% sodium hydroxide solution; dialysis purification uses a dialysis bag with a cut - off molecular weight of 8000 - 14000 for 72 hours; then, under the condition of 60 °C, vacuum dry for 24 hours;

[0066] Step S2: Disperse the crosslinked polyvinyl alcohol resin obtained in Step S1 in a mixed solvent of N,N-dimethylformamide and water, add maleic acid and a radical initiator, react at 90 °C for 6 hours under nitrogen protection, cool to room temperature in an ice bath, then drop the reaction solution into anhydrous ethanol five times the volume of the reaction solution for precipitation. Keep stirring during the precipitation process to avoid agglomeration. Then centrifuge at 8000 rpm for 15 minutes, wash once with a mixed solution of ethanol and water with a volume ratio of 3:1 and twice with anhydrous ethanol, and then dry to constant weight at 40 °C in a vacuum drying chamber to obtain the graft-modified polyvinyl alcohol resin. The addition amount of maleic acid is 8% of the mass of the crosslinked polyvinyl alcohol in Step S1. The radical initiator is potassium persulfate, and the addition amount is 2% of the mass of maleic acid. The weight-to-volume ratio of the crosslinked polyvinyl alcohol obtained in Step 1 to the mixed solvent is: 5 g:100 ml. In the mixed solvent, the weight ratio of N,N-dimethylformamide to water is 4:0.8;

[0067] Step S3: Nano-cellulose composite reinforcement: Nano-cellulose and the graft-modified polyvinyl alcohol resin obtained in Step S2 are mechanically blended and compounded to obtain the product. Mechanical blending is carried out using a high-speed shear emulsifier at a rotation speed of 8000 rpm for 40 minutes. The addition amount of nano-cellulose is 15% of the mass of the graft-modified polyvinyl alcohol resin in Step S2.

[0068] Among them, the nano-cellulose is first pretreated with a silane coupling agent KH-550. The specific steps are as follows: Disperse the nano-cellulose in deionized water and treat it with an ultrasonic disperser for 25 minutes to obtain Solution 1. Among them, the weight-to-volume ratio of nano-cellulose to deionized water is 10 g:90 ml. Dissolve the silane coupling agent in ethanol, stir evenly, and then add it to Solution 1, and stir and react at 60 °C for 2.5 hours. Among them, the weight-to-volume ratio of the silane coupling agent to ethanol is 2 g:220 ml, and the dosage ratio of nano-cellulose to the silane coupling agent is 10:0.2. After the reaction, carry out centrifugal separation, wash 3 times with ethanol and deionized water, and dry the precipitate to constant weight to obtain the pretreated nano-cellulose.

[0069] The preparation method of the above-mentioned nano-silicon-based heat-insulating and fire-proof glass film is as follows:

[0070] Step 1: Vacuum-dry the nano-silica at 95 °C for 2.2 hours to remove the surface-adsorbed water and avoid the influence of moisture on the dispersion effect and product performance;

[0071] Step 2: Mix nano-silica and anhydrous ethanol at a ratio of 1:10 (weight-to-volume ratio), then add polyacrylamide PAM, and magnetically stir at a rotation speed of 450 rpm for 12 minutes to preliminarily disperse the nano-silica in ethanol. Then, carry out ultrasonic treatment for 60 minutes under the conditions of a frequency of 30 kHz and a power of 180 W, and control the solution temperature at 30 °C;

[0072] Step 3: Filter with a 0.2 μm filter membrane, and under a pressure of 0.2 MPa, remove the large undispersed particles in the solution after ultrasonic dispersion in Step 2 to ensure the uniformity and stability of the solution and avoid the influence of large particles on the performance and appearance quality of the film;

[0073] Step 4: Add the modified polyvinyl alcohol to the solution filtered in Step 3, and stir at 60 °C until completely dissolved. The appropriate temperature helps the resin dissolve quickly, and controlling the viscosity facilitates the subsequent mixing of additives;

[0074] Step 5: In the solution obtained in Step 4, sequentially add the stabilizer CMC, the cross-linking agent KH-550, the plasticizer (dibutyl phthalate DBP), and the remaining solvent, and perform high-speed shear stirring at a speed of 1400 rpm for 25 minutes; then, use a 0.2 μm filter membrane again to remove the residual impurities in the reaction solution; after filtration, degas at a vacuum degree of -0.1 MPa for 12 minutes to ensure that the residual bubble content ≤ 0.1%;

[0075] Step 6: Use a flat vulcanizing machine to perform hot pressing and forming at 180 °C and 10 MPa, and the pressure holding time is 4 minutes. The film is initially formed, and then, it is cooled by a gradient cooling method of 80 °C → 50 °C → room temperature;

[0076] Step 7: Place the cooled film in an oven at 80 °C and cure for 3.5 hours; then, use a chemical polishing solution with pH = 8 - 9 for polishing treatment until the surface roughness Ra ≤ 0.1 μm to obtain the film substrate;

[0077] Step 8: After mixing the thermoplastic polyurethane elastomer rubber and hollow glass microspheres in a weight ratio of 100:15, calender them into a film by an extruder, and then thermally press and compound them with the film substrate at a hot pressing temperature of 120 °C, a pressure of 0.8 MPa, and a time of 60 seconds;

[0078] Step 9: Mix the waterborne acrylic resin ammonium polyphosphate, aluminum hydroxide, acrylic emulsion, and substrate wetting agent TEGOTwin 4100 evenly, coat them on the sound insulation layer, and then dry at 75 °C to obtain it. Among them, the weight ratio of the waterborne acrylic resin ammonium polyphosphate, aluminum hydroxide, acrylic emulsion, and substrate wetting agent TEGO Twin 4100 is 65:15:20:10:3. Example 3

[0079] A nano-silicon-based heat-insulating and fireproof glass film, comprising a film base layer, a sound-insulating layer and a flame-retardant layer sequentially arranged on the film base layer. The film base layer comprises the following components by weight: 30 parts of nano-silica, 50 parts of matrix resin, 1 part of dispersant, 3 parts of stabilizer, 1 part of cross-linking agent, 5 parts of plasticizer, and 10 parts of solvent. The matrix resin is modified polyvinyl alcohol, the dispersant is polyacrylamide, the stabilizer is sodium carboxymethyl cellulose, the cross-linking agent is silane coupling agent KH-550, the plasticizer is dibutyl phthalate, and the solvent is absolute ethanol.

[0080] The preparation method of the modified polyvinyl alcohol is as follows:

[0081] Step S1: Dissolve polyvinyl alcohol in water, add polyethylene glycol diglycidyl ether (PEGDE) as a cross-linking agent, and react at 60 °C for 2 hours at pH 10-11. After dialysis purification and drying, cross-linked polyvinyl alcohol resin is obtained. The molecular weight of the polyethylene glycol diglycidyl ether (PEGDE) is 400-1000, and the addition amount is 15% of the mass of polyvinyl alcohol. The weight-to-volume ratio of polyvinyl alcohol to water is 12 g:100 ml. The alkaline condition is adjusted by adding a 30% sodium hydroxide solution. Dialysis purification is carried out using a dialysis bag with a molecular weight cut-off of 8000-14000 for 48 hours. Then, under the condition of 50 °C, vacuum drying is carried out for 48 hours.

[0082] Step S2: Disperse the cross-linked polyvinyl alcohol resin obtained in Step S1 in a mixed solvent of N,N-dimethylformamide and water, add maleic acid and a radical initiator, and react at 100 °C for 4 hours under nitrogen protection. Cool to room temperature in an ice bath, then drop the reaction solution into anhydrous ethanol with a volume 3 times that of the reaction solution for precipitation. Stir during the precipitation process to avoid agglomeration. Then, centrifuge at 10000 rpm for 10 minutes, wash once with a mixed solution of ethanol and water with a volume ratio of 3:1, and wash twice with anhydrous ethanol. Then, dry to constant weight at 45 °C in a vacuum drying chamber to obtain graft-modified polyvinyl alcohol resin. The addition amount of maleic acid is 20% of the mass of the cross-linked polyvinyl alcohol in Step S1. The radical initiator is potassium persulfate, and the addition amount is 3% of the mass of maleic acid. The weight-to-volume ratio of the cross-linked polyvinyl alcohol obtained in Step 1 to the mixed solvent is: 10 g:100 ml. In the mixed solvent, the weight ratio of N,N-dimethylformamide to water is 4:1.2.

[0083] Step S3: Nano-cellulose composite reinforcement: Mechanically blend and compound nano-cellulose with the graft-modified polyvinyl alcohol resin obtained in Step S2 to obtain it. The mechanical blending is carried out using a high-speed shear emulsifier at a rotation speed of 12000 rpm for 20 minutes. The addition amount of nano-cellulose is 5% of the mass of the graft-modified polyvinyl alcohol resin in Step S2.

[0084] Among them, the nanocellulose is first pretreated with a silane coupling agent KH-550. The specific steps are as follows: Disperse the nanocellulose in deionized water and treat it with an ultrasonic disperser for 35 minutes to obtain Solution 1, where the weight-volume ratio of nanocellulose to deionized water is 10 g:110 ml; dissolve the silane coupling agent in ethanol, stir evenly, and then add it to Solution 1. Stir and react at 80 °C for 1.5 hours, where the weight-volume ratio of the silane coupling agent to ethanol is 2 g:180 ml, and the dosage ratio of nanocellulose to the silane coupling agent is 10:0.15; after the reaction, perform centrifugal separation, wash 3 times with ethanol and deionized water, and dry the precipitate to constant weight to obtain pretreated nanocellulose.

[0085] The preparation method of the above-mentioned nano-silicon-based heat-insulating and fire-proof glass film is as follows:

[0086] Step 1, vacuum-dry the nano-silica at 105 °C for 1.8 hours to remove the surface-adsorbed water and avoid the influence of moisture on the dispersion effect and product performance;

[0087] Step 2, mix the nano-silica and absolute ethanol in a ratio of 1:5 (weight-volume ratio), then add polyacrylamide PAM, and magnetically stir at a speed of 550 rpm for 8 minutes to preliminarily disperse the nano-silica in ethanol; then, perform ultrasonic treatment for 30 minutes under the conditions of a frequency of 40 kHz and a power of 220 W, and control the solution temperature at 25 °C;

[0088] Step 3, filter with a 0.2-μm filter membrane and remove the large undispersed particles in the solution after ultrasonic dispersion in Step 2 under a pressure of 0.2 MPa to ensure the uniformity and stability of the solution and avoid the influence of large particles on the performance and appearance quality of the film;

[0089] Step 4, add the modified polyvinyl alcohol PVA to the solution filtered in Step 3 and stir at 80 °C until completely dissolved. The appropriate temperature helps the resin dissolve quickly and controls the viscosity for the subsequent mixing of additives;

[0090] Step 5, in the solution obtained in Step 4, sequentially add the stabilizer CMC, the cross-linking agent KH-550, the plasticizer (dibutyl phthalate DBP), and the remaining solvent, and perform high-speed shear stirring at a speed of 1600 rpm for 15 minutes; then, use a 0.2-μm filter membrane again to remove the residual impurities in the reaction solution; after filtration, perform degassing at a vacuum degree of -0.1 MPa for 18 minutes to ensure that the residual bubble content ≤ 0.1%;

[0091] Step 6, use a flat vulcanizing machine to perform hot pressing and molding under the conditions of 160 °C and 8 MPa, and the pressure-holding time is 6 minutes. The film is initially formed, and then, it is cooled by a gradient cooling method of 80 °C → 50 °C → room temperature;

[0092] Step 7: Put the cooled film into an oven at 100 °C for curing for 2.5 hours; then polish it with a chemical polishing solution with pH = 8 - 9 until the surface roughness Ra ≤ 0.1 μm to obtain a film base layer.

[0093] Step 8: After mixing thermoplastic polyurethane elastomer rubber and hollow glass microspheres in a weight ratio of 100:10, calender them into a film by an extruder, and then hot - press and compound them with the film base layer at a hot - press temperature of 130 °C, a pressure of 0.8 MPa, and a time of 30 seconds.

[0094] Step 9: Mix water - borne acrylic resin ammonium polyphosphate, aluminum hydroxide, acrylic emulsion, and substrate wetting agent TEGOTwin 4100 evenly, then coat them on the sound - insulation layer, and then dry them at 85 °C. Among them, the weight ratio of water - borne acrylic resin ammonium polyphosphate, aluminum hydroxide, acrylic emulsion, and substrate wetting agent TEGO Twin 4100 is 50:25:10:8:1. Example 4

[0095] A nano - silicon - based heat - insulating and fire - proof glass film, wherein the matrix resin is polyurethane, and the rest is the same as in Example 1.

[0096] Comparative Example 1

[0097] A nano - silicon - based heat - insulating and fire - proof glass film, wherein the matrix resin is unmodified polyvinyl alcohol, and the rest is the same as in Example 1.

[0098] Performance test and results

[0099] Compound the films obtained from the above - mentioned Examples 1 - 4 and the comparative example with two glass substrates together to form a fire - proof glass with a structure of two pieces of glass sandwiching a film, and then conduct performance tests on the obtained fire - proof glass.

[0100] 1. Visible light transmittance, thermal conductivity

[0101] Use a spectrophotometer to measure its visible light transmittance at a wavelength of 550 nm; use LFA 467 NanoFlash to measure the thermal conductivity.

[0102] 2. According to GB15763.1 - 2009 "Safety Glass for Building - Part 1: Fire - proof Glass", test the fire - resistance and impact - resistance performance of the fire - proof glasses prepared in Examples 1 - 4 and Comparative Example 1, and the test results are shown in Table 1.

[0103]

[0104] As can be seen from Table 1, the laminated glass obtained in Examples 1-4 of the present invention has better light transmittance, fire resistance, heat insulation and impact resistance than Comparative Example 1. Its high visible light transmittance can improve the daylighting effect of the glass and meet the daylighting requirements of buildings. The fire resistance time is ≥1.2 hours, far exceeding the requirement of ≥1 hour for Class A fireproof glass in the national standard, significantly improving fire safety. The long fire resistance limit can enable the fireproof glass to provide protection for a longer time in case of fire, effectively protecting the safety of personnel and property. The thermal conductivity is low ≤0.1W / m·K, effectively enhancing the heat insulation performance and reducing energy consumption. The low thermal conductivity can enable the fireproof glass to provide better heat insulation effect while ensuring the fireproof performance, reducing the energy consumption of buildings. It has good impact resistance, and there is no splashing when broken, improving the safety performance.

[0105] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variation thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0106] Although the embodiments of the present application have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present application. The scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A nano-silicon-based heat-insulating and fire-proof glass film, characterized in that, It includes a film base layer, a sound insulation layer, and a flame retardant layer sequentially disposed on the film base layer. The film base layer comprises the following components by weight parts: 10-30 parts of nano-silica, 50-70 parts of matrix resin, 1-3 parts of dispersant, 1-3 parts of stabilizer, 1-3 parts of crosslinking agent, 5-10 parts of plasticizer, and 10-32 parts of solvent. The matrix resin is modified polyvinyl alcohol, and the preparation method of the modified polyvinyl alcohol is as follows: Step S1: Dissolve polyvinyl alcohol in water, add polyethylene glycol diglycidyl ether as a crosslinking agent, and react at 50-60 °C for 2-4 hours under alkaline conditions. After dialysis purification and drying, crosslinked polyvinyl alcohol resin is obtained; Step S2: Disperse the crosslinked polyvinyl alcohol resin obtained in Step S1 in a mixed solvent of N,N-dimethylformamide and water, add maleic acid and a radical initiator, and react at 90-100 °C for 4-6 hours under nitrogen protection. Then, perform precipitation, centrifugation, and drying to obtain graft-modified polyvinyl alcohol resin; Step S3: Mechanically blend and compound nano-cellulose with the graft-modified polyvinyl alcohol resin obtained in Step S2 to obtain the product.

2. The nano-silicon-based heat-insulating and fireproof glass film according to claim 1, wherein In Step S1, the addition amount of polyethylene glycol diglycidyl ether is 5-15% of the mass of polyvinyl alcohol; the weight-to-volume ratio of polyvinyl alcohol to water is 8-12 g:100 ml.

3. The nano-silicon-based heat-insulating and fire-proof glass film according to claim 1, characterized in that In Step S1, the pH of the alkaline condition is 10-11, which is adjusted by sodium hydroxide; dialysis purification is carried out using a dialysis bag with a molecular weight cut-off of 8000-14000 for 48-72 hours.

4. The nano-silicon-based heat-insulating and fireproof glass film according to claim 1, wherein In Step S2, the addition amount of maleic acid is 8-20% of the mass of the crosslinked polyvinyl alcohol in Step S1; the radical initiator is potassium persulfate, and the addition amount is 2-3% of the mass of maleic acid; the weight-to-volume ratio of the crosslinked polyvinyl alcohol obtained in Step 1 to the mixed solvent is: 5-10 g:100 ml, and the weight ratio of N,N-dimethylformamide to water in the mixed solvent is 4:0.8-1.

2.

5. The nano-silicon-based heat-insulating and fireproof glass film according to claim 1, characterized in that, In Step S3, the addition amount of nano-cellulose is 5-15% of the mass of the graft-modified polyvinyl alcohol resin in Step S2.

6. The nano-silicon-based heat-insulating and fire-proof glass film according to claim 1, characterized in that, In Step S3, the nano-cellulose is pretreated with a silane coupling agent KH-550.

7. The nano-silicon-based heat-insulating and fire-proof glass film according to claim 1, wherein The specific steps for pretreating the nano-cellulose with a silane coupling agent are as follows: Disperse the nano-cellulose in deionized water, and treat it with an ultrasonic disperser for 25-35 minutes to obtain Solution 1; dissolve the silane coupling agent in ethanol, stir evenly, and then add it to Solution 1. Stir and react at 60-80 °C for 1.5-2.5 hours. After the reaction, perform centrifugal separation, wash 3 times with ethanol and deionized water, and dry the precipitate to obtain pretreated nano-cellulose; wherein, the weight-to-volume ratio of nano-cellulose to deionized water is 10 g:90-110 ml, the weight-to-volume ratio of the silane coupling agent to ethanol is 2 g:180-220 ml, and the dosage ratio of nano-cellulose to the silane coupling agent is 10:0.15-0.

25.

8. The nano-silicon-based heat-insulating and fireproof glass film according to claim 1, characterized in that The dispersant is polyacrylamide, the stabilizer is sodium carboxymethyl cellulose, the crosslinking agent is silane coupling agent, the plasticizer is dibutyl phthalate, and the solvent is absolute ethanol.

9. The nano-silicon-based heat-insulating and fireproof glass film according to claim 1, wherein The sound insulation layer is mainly made of thermoplastic polyurethane elastomer rubber and hollow glass microspheres, and the flame retardant layer is mainly made of waterborne acrylic resin and ammonium polyphosphate.

10. The preparation method of the nano-silicon-based heat-insulating and fireproof glass film according to any one of claims 1-8, characterized in that, The preparation method of the film base layer includes the following steps: nano-silica pretreatment → ultrasonic dispersion → resin dissolution → mixing → filtration and degassing → hot pressing and forming, gradient cooling → crosslinking and curing, polishing.

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