Fireproof composite structure, method for manufacturing the same, and composite side window glass

Abstract

The application relates to a composite material structure for fire prevention and a preparation method and a composite side window glass. The composite material structure for fire prevention at least comprises an interpenetrating network layer, the interpenetrating network layer is an interpenetrating network structure layer made of an adhesive and K2O.nSiO2-based nanometer hard fibers with a diameter of 900 nm to 2.5 mu m and a modulus of 4.5 to 5.5; the K2O.nSiO2-based nanometer hard fibers with a high modulus are prepared from the following raw materials in parts by weight: 18 to 75 parts of tetraethyl orthosilicate, 0.1 to 0.5 parts of nitric acid, 30 to 120 parts of deionized water, 50 to 200 parts of a polyethylene glycol aqueous solution, 1 to 2 parts of ethanol, 0.5 to 1 part of a reactive emulsifier SE-10N, 0.4 to 1.2 parts of ammonia water and 3 to 6 parts of potassium hydroxide by using a multi-channel in-situ electrospinning method. The composite side window glass has the functions of fire prevention and heat insulation and has a long service life.

Description

Technical Field

[0001] This invention relates to the field of side window glass for high-speed locomotives, specifically a fire-resistant composite material structure and its preparation method, and a special side window glass for high-speed trains with speeds of 350 km / h or higher. Background Technology

[0002] In the sea, land, and air transportation system composed of airplanes, trains, automobiles, and ships, railway transportation has the characteristics of large capacity, high speed, long distance, low cost, and low pollution. It has gradually won out in competition with other modes of transportation and become the most important transportation system. High-speed railways can transport a large amount of goods and people to distant places in a shorter time, driving the rapid economic development of the railway line, the region, and even the whole country, thus becoming the leader in the railway system.

[0003] Currently, the side window glass used in most domestic trains is ordinary safety glass, which cannot meet the fire safety requirements of high-speed locomotives, especially the safety requirements of high-speed locomotives with speeds exceeding 350 km / h. Summary of the Invention

[0004] The main objective of this invention is to provide a fire-resistant composite material structure and its preparation method, as well as a composite side window glass, which overcomes the drawback of PVB film used in high-speed locomotives being unable to retard flames in sudden fires, and avoids the disadvantages of PVB adhesive layer being flammable, bubbling, and having poor impact resistance.

[0005] The objective of this invention and the technical problem it solves are achieved by the following technical solutions.

[0006] A fire-resistant composite material structure includes an interpenetrating network layer, wherein the interpenetrating network layer is an interpenetrating network structure layer made of an adhesive and K2O·nSiO2-based rigid nanofibers with a diameter of 900 nm to 2.5 μm and a modulus of 4.5 to 5.5; the K2O·nSiO2-based rigid nanofibers are rigid fibers obtained by using a K2O·nSiO2-based pre-reaction spinning solution through the following steps:

[0007] S101) Prepare the following components: 18-75 parts by weight of tetraethyl orthosilicate, 0.1-0.5 parts by weight of nitric acid, 30-120 parts by weight of deionized water, 50-200 parts by weight of polyvinyl alcohol aqueous solution, 1-2 parts by weight of ethanol, 0.5-1 parts by weight of reactive emulsifier SE-10N, 0.1-1.2 parts by weight of ammonia water, and 3-6 parts by weight of potassium hydroxide, wherein the solid content of the polyvinyl alcohol aqueous solution is 15 wt%, the molecular weight of the polyvinyl alcohol used to prepare the polyvinyl alcohol aqueous solution is 80,000-100,000, the degree of hydrolysis of polyvinyl alcohol in the polyvinyl alcohol aqueous solution is 85%-90%, the concentration of ammonia water is 20 wt%, and the purity of potassium hydroxide is 85 wt%.

[0008] S102) Preparation of the first mixed solution: Tetraethyl orthosilicate, nitric acid and deionized water are mixed and stirred at room temperature for at least 60 min. After the mixture forms a multi-peaked and broadly distributed silica sol with a particle size of 40-360 nm, it is stirred for another 60 min to obtain the first mixed solution.

[0009] S103) Add polyvinyl alcohol aqueous solution, ethanol and reactive emulsifier SE-10N to the first mixed solution and stir at room temperature for at least 60 min to obtain a second mixed solution with a viscosity in the range of 100 to 300 mPa·s;

[0010] S104) Ammonia water is slowly added to the second mixed solution and stirred at room temperature for at least 60 minutes to obtain a third mixed solution with a pH value maintained in the range of 6 to 7;

[0011] S105) Potassium hydroxide is added stepwise to the third mixed solution and the temperature of the solution system is kept below 25℃. Then, vacuum defoaming is performed for 60 minutes to obtain a K2O·nSiO2-based pre-reaction spinning solution with a viscosity in the range of 350 to 800 mPa·s.

[0012] S106) K2O·nSiO2-based nanofibers were prepared by spinning using K2O·nSiO2-based pre-reaction spinning solution.

[0013] The fire-resistant composite material structure described above further includes an adhesive layer, and the interpenetrating network layer is located between two of the adhesive layers.

[0014] The fire-resistant composite material structure further includes a K2O·nSiO2-based nanofiber filling layer, which is located between the two interpenetrating network layers.

[0015] The fire-resistant composite material structure further includes an adhesive layer and a K2O·nSiO2-based nanofiber filling layer; in the fire-resistant composite material structure, the interpenetrating network layer and the adhesive layer are sequentially arranged from the inside to the outside on both sides of the K2O·nSiO2-based nanofiber filling layer.

[0016] In the aforementioned fire-resistant composite material structure, the adhesive is polyvinyl butyral adhesive, and the adhesive layer is a polyvinyl butyral film layer.

[0017] In the aforementioned fire-resistant composite material structure, the thickness of the polyvinyl butyral film layer is 0.3–1.5 mm.

[0018] The preparation method of the above-mentioned fire-resistant composite material structure includes the following steps:

[0019] S100) Preparation of K2O·nSiO2-based rigid nanofibers: A K2O·nSiO2-based rigid nanofiber filling layer is prepared using K2O·nSiO2-based rigid nanofibers, wherein the K2O·nSiO2-based rigid nanofibers are rigid fibers obtained using a K2O·nSiO2-based pre-reaction spinning solution through the following steps:

[0020] S101) Prepare the following components: 18-75 parts by weight of tetraethyl orthosilicate, 0.1-0.5 parts by weight of nitric acid, 30-120 parts by weight of deionized water, 50-200 parts by weight of polyvinyl alcohol aqueous solution, 1-2 parts by weight of ethanol, 0.5-1 parts by weight of reactive emulsifier SE-10N, 0.1-1.2 parts by weight of ammonia water, and 3-6 parts by weight of potassium hydroxide, wherein the solid content of the polyvinyl alcohol aqueous solution is 15 wt%, the molecular weight of the polyvinyl alcohol in the polyvinyl alcohol aqueous solution is 80,000-100,000 and the degree of hydrolysis of polyvinyl alcohol is 85%-90%, the concentration of ammonia water is 20 wt%, and the purity of potassium hydroxide is 85 wt%.

[0021] S102) Preparation of the first mixed solution: Tetraethyl orthosilicate, nitric acid and deionized water are mixed and stirred at room temperature for at least 60 min. After the mixture forms a multi-peaked and broadly distributed silica sol with a particle size of 40-360 nm, it is stirred for another 60 min to obtain the first mixed solution.

[0022] S103) Add polyvinyl alcohol aqueous solution, ethanol and reactive emulsifier SE-10N to the first mixed solution and stir at room temperature for at least 60 min to obtain a second mixed solution with a viscosity in the range of 100 to 300 mPa·s;

[0023] S104) Ammonia water is slowly added to the second mixed solution and stirred at room temperature for at least 60 minutes to obtain a third mixed solution with a pH value maintained in the range of 6 to 7;

[0024] S105) Potassium hydroxide is added stepwise to the third mixed solution and the temperature of the solution system is kept below 25℃. Then, vacuum defoaming is performed for 60 minutes to obtain a K2O·nSiO2-based pre-reaction spinning solution with a viscosity in the range of 350 to 800 mPa·s.

[0025] S106) K2O·nSiO2-based nanofibers were prepared by spinning using K2O·nSiO2-based pre-reaction spinning solution.

[0026] S200) The fire-resistant composite material structure is prepared by the following steps:

[0027] S201) The K2O·nSiO2-based rigid nanofibers obtained in step S100) are pressed together with an adhesive to form an interpenetrating network structure.

[0028] The above method also includes the following steps:

[0029] S202) The adhesive layer, the interpenetrating network layer and the K2O·nSiO2-based nanofiber filling layer are pressed together to form a fireproof composite material structure; in the fireproof composite material structure, the interpenetrating network layer and the adhesive layer are arranged sequentially from the inside to the outside on both sides of the K2O·nSiO2-based nanofiber filling layer.

[0030] A composite side window glass, used as a side window glass for high-speed locomotives, comprises m layers of ultra-strong chemically tempered glass, n layers of physically tempered glass, an adhesive layer, a hollow layer, and a splash-proof layer, where m is an integer greater than or equal to 1, and n is an integer greater than or equal to 2; when m equals 1, at least the ultra-strong chemically tempered glass is connected to the first layer of physically tempered glass or to two adjacent layers of physically tempered glass through the adhesive layer; when m is greater than 1, at least two adjacent layers of ultra-strong chemically tempered glass or the ultra-strong chemically tempered glass is connected to the first layer of physically tempered glass or to two adjacent layers of physically tempered glass through the adhesive layer; wherein, at least one of the adhesive layers is an adhesive layer made of the aforementioned fire-resistant composite material structure.

[0031] In the aforementioned composite side window glass, the surface stress of the ultra-strong chemically tempered glass is 400MPa to 900MPa and the stress layer depth is 20 to 50μm, and the thickness of the ultra-strong chemically tempered glass is 3 to 10mm.

[0032] The beneficial effects of this invention are as follows:

[0033] 1. K₂O·nSiO₂, as an inorganic solid material, is brittle and cannot be directly extruded, injection molded, compressed, or stretched into filaments. Furthermore, as an inorganic salt, K₂O·nSiO₂ is highly water-soluble and cannot be prepared into a colloidal solution. This invention utilizes the sol-gel method to synthesize a core-shell structured SiO₂ sol with the aid of polyvinyl alcohol and an emulsifier. By leveraging the steric hindrance effect of polyvinyl alcohol, the reaction between silicon dioxide and potassium hydroxide is delayed at room temperature (25°C) to obtain a K₂O·nSiO₂-based pre-reacting spinning solution. Then, using multi-channel in-situ electrospinning technology, K₂O·nSiO₂-based nanofiber membranes of varying thicknesses are prepared.

[0034] 2. Due to the poor compatibility between PVB film and K2O·nSiO2 material, it is impossible to directly prepare composite films with a PVB / high-modulus K2O·nSiO2-based nanofiber / PVB structure. This invention utilizes a roll pressing process to press incompletely reacted low-modulus K2O·nSiO2-based nanofibers into PVB film, forming a PVB / low-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network layer. Further hot pressing generates a PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network layer, improving the penetration ability of K2O·nSiO2-based fibers in the PVB film. The interpenetrating network structure also increases the bonding force between PVB and K2O·nSiO2, creating a reinforcement effect similar to reinforced concrete.

[0035] 3. The reason why the PVB / high-modulus K2O·nSiO2-based nanofiber / PVB film of this invention has flame retardancy and flame spread isolation is that: the K2O·nSiO2-based material that forms an interpenetrating network structure with the PVB film will quickly foam when exposed to an open flame, forming a heat insulation layer that prevents the flame from penetrating the film, thereby ensuring the integrity of the glass on the unexposed side of the high-speed train; the first layer of PVB film also acts as a charring agent, which can carbonize at high temperatures to form long-chain carbides and absorb a large amount of heat; the second layer of PVB film will not come into direct contact with an open flame due to the presence of the K2O·nSiO2-based foamed heat insulation layer. Over time, this layer of film will only slowly heat up and will not ignite, thereby improving the fire safety performance of the train side window glass.

[0036] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of a composite side window glass according to an embodiment of the present invention.

[0038] In the figure, 1-Ultra-strong chemically tempered glass; 2-Interpenetrating network layer; 3-First physical tempered glass; 4-Insulated layer; 5-Second physical tempered glass; 6-Adhesive layer; 7-K2O·nSiO2-based nano-hard fiber filling layer; 8-Anti-splash layer. Detailed Implementation

[0039] The composite side window glass of this invention includes m layers of ultra-strong chemically tempered glass 1, n layers of physically tempered glass, an adhesive layer, a hollow layer, and a splash-proof layer, where m is an integer greater than or equal to 1, and n is an integer greater than or equal to 2. When m equals 1, at least the ultra-strong chemically tempered glass is connected to the first layer of physically tempered glass or to two adjacent layers of physically tempered glass through the adhesive layer. When m is greater than 1, at least two adjacent layers of ultra-strong chemically tempered glass, or the ultra-strong chemically tempered glass is connected to the first layer of physically tempered glass or to two adjacent layers of physically tempered glass through the adhesive layer. At least one of the adhesive layers is made of a fire-resistant composite material structure. A hollow layer is provided between the (n-1)th layer of physically tempered glass and the nth layer of physically tempered glass, and a splash-proof layer 8 is provided on the surface of the nth layer of physically tempered glass, which is away from the (n-1)th layer of physically tempered glass.

[0040] The adhesive layer in this invention includes an adhesive layer 6, an interpenetrating network layer 2, and a K2O·nSiO2-based nanofiber filling layer 7. The K2O·nSiO2-based nanofiber filling layer 7 is disposed between two interpenetrating network layers 2, and the adhesive layer 6 is disposed on the outside of the interpenetrating network layers 2. The interpenetrating network layer 2 is an interpenetrating network structure layer made of an adhesive and K2O·nSiO2-based nanofibers with a diameter of 900 nm to 2.5 μm and a modulus of 4.5 to 5.5. The K2O·nSiO2-based nanofiber filling layer 7 is a filling layer made of K2O·nSiO2-based nanofibers with a diameter of 900 nm to 2.5 μm and a modulus of 4.5 to 5.5. The adhesive is polyvinyl butyral adhesive, and the adhesive layer 6 is a polyvinyl butyral film layer.

[0041] The adhesive layer is made by laminating polyvinyl butyral film (PVB film) and K2O·nSiO2-based nanofibers. The specific preparation method is as follows:

[0042] S100) Preparation of K2O·nSiO2-based rigid nanofibers: A K2O·nSiO2-based rigid nanofiber filling layer is prepared using K2O·nSiO2-based rigid nanofibers, wherein the K2O·nSiO2-based rigid nanofibers are rigid fibers obtained using a K2O·nSiO2-based pre-reaction spinning solution through the following steps:

[0043] S101) Prepare the following components: 18-75 parts by weight of tetraethyl orthosilicate, 0.1-0.5 parts by weight of nitric acid, 30-120 parts by weight of deionized water, 50-200 parts by weight of polyvinyl alcohol aqueous solution, 1-2 parts by weight of ethanol, 0.5-1 parts by weight of reactive emulsifier SE-10N, 0.1-1.2 parts by weight of ammonia water, and 3-6 parts by weight of potassium hydroxide, wherein the solid content of the polyvinyl alcohol aqueous solution is 15 wt%, the molecular weight of the polyvinyl alcohol used to prepare the polyvinyl alcohol aqueous solution is 80,000-100,000, the degree of hydrolysis of polyvinyl alcohol in the polyvinyl alcohol aqueous solution is 85%-90%, the concentration of ammonia water is 20 wt%, and the purity of potassium hydroxide is 85 wt%.

[0044] S102) Preparation of the first mixed solution: Tetraethyl orthosilicate, nitric acid and deionized water are mixed and stirred at room temperature for at least 60 min. After the mixture forms a multi-peaked and broadly distributed silica sol with a particle size of 40-360 nm, it is stirred for another 60 min to obtain the first mixed solution.

[0045] S103) Add polyvinyl alcohol aqueous solution, ethanol and reactive emulsifier SE-10N to the first mixed solution and stir at room temperature for at least 60 min to allow polyvinyl alcohol to be uniformly coated on the surface of silica sol, and obtain a second mixed solution with a viscosity in the range of 100 to 300 mPa·s.

[0046] S104) Ammonia water is slowly added to the second mixed solution and stirred at room temperature for at least 60 minutes to obtain a third mixed solution with a pH value maintained in the range of 6 to 7;

[0047] S105) Potassium hydroxide is added stepwise to the third mixed solution and the temperature of the solution system is kept below 25℃. Then, vacuum defoaming is performed for 60 minutes to obtain a K2O·nSiO2-based pre-reaction spinning solution with a viscosity in the range of 350 to 800 mPa·s.

[0048] S106) K2O·nSiO2-based hard nanofibers were prepared by spinning using K2O·nSiO2-based pre-reactive spinning solution. The specific operation was as follows: at room temperature, the K2O·nSiO2-based pre-reactive spinning solution was injected into a multi-channel in-situ electrospinning device. A stainless steel needle with a diameter of 0.8 mm was used as a metal nozzle, and a grounded stainless steel cylinder covered with aluminum foil was used as a collector. The distance between the nozzle and the collector was 15 cm. The electrospinning voltage was set to 20 kV, and the pre-reactive spinning solution was spun into the collector at a rate of 0.6 ml / h per channel. A low-modulus K2O·nSiO2-based nanofiber network in the form of nonwoven fabric was formed on its surface. The fiber diameter was 900 nm to 2.5 μm. By controlling the spinning time, low-modulus K2O·nSiO2-based nanofiber membranes of different thicknesses could be obtained.

[0049] The adhesive layer is prepared using S200, and the specific steps are as follows:

[0050] S201) Peel the K2O·nSiO2-based nanofiber membrane from the aluminum foil and place it evenly between two 0.38mm PVB films. Then place a 0.1mm polyimide (PI) film on each side of the PVB / low-modulus K2O·nSiO2-based nanofiber membrane / PVB composite to ensure the isolation between PVB and glass.

[0051] S202) The combination of 5mm tempered glass / PI / PVB / low modulus K2O·nSiO2-based nanofiber film / PVB / PI / 5mm tempered glass is placed into a continuous roller press for hot pressing. After the first heat treatment by rolling (pressure 0.3±0.1MPa, temperature 40±5℃, roller gap less than 10% of the thickness of the assembly), the second heat treatment by rolling (pressure 0.5±0.1MPa, temperature 70±5℃, roller gap less than 15% of the thickness of the assembly) is performed, finally obtaining the adhesive layer (PVB / high modulus K2O·nSiO2-based nanofibers / PVB interpenetrating network film). In this layer, the K2O·nSiO2-based nanofiber membrane penetrates into the PVB film to a certain depth to form an interpenetrating network structure. The remaining part of the PVB film acts as the adhesive layer, while the K2O·nSiO2-based nanofiber membrane that does not form an interpenetrating network structure with PVB forms a K2O·nSiO2-based nanofiber filling layer.

[0052] K2O·nSiO2-based pre-reactive spinning solution is prepared from silica sol obtained by acid hydrolysis of tetraethyl orthosilicate. The silica sol consists of bimodal, broadly distributed nanoparticles with a core-shell structure. The core layer material is nano-silica sol and its aggregates, and the shell material is polyvinyl alcohol. The surface tension of the spinning solution is controlled within the range of 28.50±7.50 mN / m, and the modulus is controlled between 4.5 and 5.5.

[0053] As a preferred embodiment, the K2O·nSiO2-based pre-reactive spinning solution, by weight, comprises the following raw materials: 25-55 parts of tetraethyl orthosilicate, 0.2-0.4 parts of nitric acid, 45-70 parts of deionized water, 75-133 parts of polyethanol aqueous solution (solid content: 15wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.2-1.6 parts of ethanol, 0.6-0.8 parts of reactive emulsifier SE-10N, 0.6-1.0 parts of ammonia (20wt%), and 4.0-5.5 parts of potassium hydroxide (purity 85wt%).

[0054] In a preferred embodiment, the nano-silica sol has a particle size of 80nm to 200nm and a bimodal broad particle size distribution. The core layer of the core-shell structured silica sol has a particle size of 70nm to 160nm, a shell thickness of 10nm to 20nm, and a viscosity of 80 to 150mPa·s.

[0055] This invention uses a core-shell structured silica sol as the main raw material for high-modulus K₂O·nSiO₂-based rigid nanofibers. The silica sol has a particle size of 40 nm to 360 nm, with a core particle size of 20 nm to 260 nm; the shell material is polyvinyl alcohol, with a shell thickness of 10 nm to 50 nm. This invention features low viscosity and a low reaction rate at room temperature (25°C), enabling the preparation of rigid nanofibers with controllable diameter. Furthermore, it can be used at low temperatures down to -55°C ± 1°C and withstands ultraviolet radiation for over 4000 hours.

[0056] The reason why this PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film has the properties of low temperature resistance and UV radiation resistance is:

[0057] 1. High-modulus K2O·nSiO2-based nanofibers have high solid content and very low free water content;

[0058] 2. The sealing performance of PVB film can firmly encapsulate the high-modulus K2O·nSiO2-based nanofibers, preventing the loss of free water and bound water in K2O·nSiO2, and ensuring that the transmittance of PVB / high-modulus K2O·nSiO2-based nanofibers / PVB interpenetrating network film will not gradually decrease under long-term ultraviolet radiation.

[0059] 3. The density of the PVB film and the presence of the K2O·nSiO2-based fiber / PVB interpenetrating network ensure that the remaining trace amounts of free water will not form large-sized, continuous ice crystal phases in low-temperature environments, thus ensuring the transparency of the locomotive glass under extremely cold conditions.

[0060] The nano-silica sol used in this embodiment of the invention has a core-shell structure, which enriches different components on the inner or outer side of the particles, i.e., core-shell particles, thereby giving the core and shell different functions and obtaining particles with excellent performance; wherein the core material is nano-silica sol and the shell material is polyvinyl alcohol. During low-temperature storage, the shell material encapsulates the core material, silica sol, and isolates the silica from potassium hydroxide, preventing a reversal reaction. When the temperature is higher, above the glass transition temperature of the shell polymer, the shell polymer changes from a glassy state to a rubbery state. The potassium hydroxide solution penetrates into the shell and reacts with the silica sol to form potassium silicate solution, i.e., potassium silicate (its structural formula is K2O·nSiO2, where n is the modulus). The silica network skeleton formed after the potassium silicate hardens has very little decrease in hardness at high temperatures, exhibits good flame retardancy, and is heat-resistant and fireproof. Furthermore, its high hardness enhances the hardness and heat resistance of PVB / high-modulus K2O·nSiO2-based nanofiber membrane / PVB interpenetrating network film.

[0061] The composite side window glass in this invention is prepared by the following steps:

[0062] A PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film is laid on the ultra-strong chemically tempered glass. A first layer of physically tempered glass is then laid on the PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film. Finally, the laminated tempered glass (including ultra-strong chemically tempered glass and physically tempered glass, hereinafter the same) and PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film are combined. The iO2-based nanofiber / PVB interpenetrating network film is placed together in a vacuum bag and evacuated. The vacuum bag is then placed in an autoclave and reacted at 110–115°C and 1–1.5 MPa for 0.5–1.5 hours. The vacuum bag is then removed. High-performance molecular sieves are injected into aluminum alloy spacers. The first and second layers of physically tempered glass are bonded together using high-performance weather-resistant sealing strips, or directly using thermoplastic elastomers to bond the components to the second layer of physically tempered glass. The hollow layer is then further compressed using a hollow fiber line to obtain a hollow layer. Finally, the edges are uniformly coated with silicone weather-resistant sealant using a sealing device to obtain a composite side window glass.

[0063] In the preparation of the composite side window glass in this embodiment of the invention, tetraethyl orthosilicate, nitric acid, and deionized water are stirred and hydrolyzed at room temperature to obtain a first mixed solution; polyvinyl alcohol, ethanol, and SE-10N are added to the first mixed solution to obtain a second mixed solution; ammonia is added to the second mixed solution to obtain a third mixed solution; potassium hydroxide with a purity of 85 wt% is added to the third mixed solution to obtain a K2O·nSiO2-based pre-reaction spinning solution; a low-modulus K2O·nSiO2-based nanofiber membrane is obtained using a multi-channel in-situ electrospinning device; a PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film is obtained using a rolling process; a tempered glass assembly is obtained using a high-pressure lamination process; and the composite side window glass is obtained using a hollow sealing device.

[0064] The composite side window glass provided in this invention, when exposed to fire, rapidly foams and expands the high-modulus K2O·nSiO2-based nanofibers in the side window glass to form a heat-insulating, fire-resistant foam layer, absorbing a large amount of heat generated by the fire and exhibiting excellent fire resistance. The fire-resistant film layer of the side window glass is formed using the aforementioned high-modulus K2O·nSiO2-based nanofibers, giving the side window glass advantages such as being free of microbubbles, having high transmittance, and providing long-lasting fire resistance. Preferably, there are at least two interlayers, one of which is a hollow layer, and the remaining interlayers are fire-resistant film layers.

[0065] In a preferred embodiment, the thickness of the high-modulus K2O·nSiO2-based nanofiber layer is 0.1–0.5 mm.

[0066] This invention allows for controlling the thickness of high-modulus K2O·nSiO2-based nanofibers to be between 0.1 and 0.5 mm. While ensuring the fire resistance of locomotive side window glass, the thickness of the manufactured side window glass remains relatively constant, reducing production costs and expanding its application range. In this embodiment, the fire-resistant film layer in the side window glass expands upon exposure to fire, forming a porous heat-insulating layer. The thickness of this expanded layer is approximately 20 to 50 times that of the original fiber layer. Upon exposure to fire, the glass on the fire-facing side will shatter first, and then the fire-resistant film layer attached to it will gradually form a heat-insulating layer of approximately 2 mm to 20 mm. If the fiber layer thickness is less than 0.1 mm, it is too thin to form a continuous heat-insulating layer, allowing open flames to pass directly through and ignite the PVB film behind the fiber layer. This fails to isolate heat transfer for a certain period, resulting in an overall fire resistance time lower than the design value. If the fiber layer thickness is greater than 0.5 mm, it is too thick, leading to excessively high side window glass costs. An excessively thick expanded layer can cause the entire glass to detach, thus reducing fire resistance.

[0067] The present invention will be further described below with reference to specific embodiments, but these are not intended to limit the scope of the invention.

[0068] All reagents used in the embodiments of this invention are commercially available products.

[0069] Example 1

[0070] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0071] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0072] 37.12 kg tetraethyl orthosilicate, 0.3 kg nitric acid, 57.73 kg deionized water, 100 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.8 kg ammonia (20 wt%), and 4.7 kg potassium hydroxide (purity 85 wt%). Since the particle size distribution of the nano-core-shell structured silica sol is broad, sol particles of various sizes can exist in this invention, exhibiting a bimodal state. Similarly, the particle size distribution of the sol particles in the following examples is also broad.

[0073] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution from the above raw materials according to the following steps:

[0074] Mix 37.12 kg of tetraethyl orthosilicate, 0.3 kg of nitric acid, and 57.73 kg of deionized water, and stir at room temperature for at least 60 minutes to allow the mixture to fully hydrolyze. After forming a silica sol with a particle size of 80 nm to 200 nm, stir for another 60 minutes to obtain the first mixed solution.

[0075] 100 kg of polyvinyl alcohol aqueous solution (solid content: 15 wt%; molecular weight: 80,000–100,000; degree of hydrolysis: 85%–90%), 1.5 kg of ethanol, and 0.75 kg of reactive emulsifier SE-10N were mixed and added to the first mixed solution. The mixture was stirred at room temperature for at least 60 minutes to allow the polyvinyl alcohol to be uniformly coated on the surface of the silica sol, thus obtaining the second mixed solution with a viscosity maintained in the range of 100–300 mPa·s.

[0076] 0.8 kg of ammonia water (20 wt%) was slowly added to the second mixed solution, and stirred at room temperature for at least 60 minutes to obtain the third mixed solution, ensuring that its pH value was maintained between 6 and 7.

[0077] 4.7 kg of potassium hydroxide (85 wt% purity) was added stepwise to the third mixed solution, ensuring that the temperature of the solution system was below 25 °C. After vacuum defoaming for 60 minutes, a K2O·nSiO2-based pre-reaction spinning solution was obtained, with its viscosity maintained in the range of 350–800 mPa·s.

[0078] The PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is prepared using the above-mentioned K2O·nSiO2-based pre-reactive spinning solution through the following steps:

[0079] At room temperature, a K2O·nSiO2-based pre-reactive spinning solution was injected into a multi-channel in-situ electrospinning device. A 0.8mm diameter stainless steel needle was used as the metal nozzle, and a grounded stainless steel cylinder covered with aluminum foil served as the collector. The distance between the nozzle and the collector was 15cm. The electrospinning voltage was set to 20kV, and the pre-reactive spinning solution was spun into the collector at a rate of 0.6ml / h per channel, forming a non-woven K2O·nSiO2-based nanofiber network on its surface. The fiber diameter ranged from 900nm to 2.5μm. By controlling the spinning time, low-modulus K2O·nSiO2-based nanofiber membranes of different thicknesses could be obtained.

[0080] The low-modulus K2O·nSiO2-based nanofiber membrane was peeled off from the aluminum foil and evenly placed between two 0.38mm PVB films. Then, a 0.1mm polyimide (PI) film was placed on each side of the PVB / low-modulus K2O·nSiO2-based nanofiber membrane / PVB composite to ensure the isolation between PVB and glass.

[0081] A composite material consisting of 5mm tempered glass, PI, PVB, low-modulus K2O·nSiO2-based nanofiber membrane, PVB, PI, and 5mm tempered glass is placed in a continuous roll press for hot pressing. After the first heat treatment (pressure 0.3±0.1MPa, temperature 40±5℃, roll gap less than 10% of the composite thickness), it undergoes a second heat treatment (pressure 0.5±0.1MPa, temperature 70±5℃, roll gap less than 15% of the composite thickness) to finally obtain a PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film.

[0082] The composite side window glass for high-speed locomotives in this embodiment is a composite side window glass manufactured using the above-mentioned PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film through the following steps:

[0083] (1) Prepare three pieces of 5mm thick glass, two of which are physically tempered glass and one is super strong chemically tempered glass;

[0084] (2) A PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film is laid on the ultra-strong chemically tempered glass. A first layer of physically tempered glass is then laid on the film layer. The stacked tempered glass and film layers are then placed in a vacuum bag and evacuated. The vacuum bag is then placed in an autoclave and reacted at 110–115°C and 1–1.5 MPa for 0.5–1.5 hours. The vacuum bag is then removed. High-performance molecular sieves are injected into aluminum alloy spacers. The first and second layers of physically tempered glass are bonded together using high-performance weather-resistant sealing strips, or directly using thermoplastic elastomers to bond the components to the second layer of physically tempered glass. The hollow layer is then further compressed using a hollow fiber assembly to obtain a hollow layer. Finally, the edges are uniformly coated with silicone weather-resistant sealant using a sealing device to obtain a composite side window glass, such as... Figure 1 As shown.

[0085] Example 2

[0086] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0087] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0088] 37.12 kg tetraethyl orthosilicate, 0.2 kg nitric acid, 57.73 kg deionized water, 100 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.5 kg ammonia (20 wt%), and 4.7 kg potassium hydroxide (purity 85 wt%);

[0089] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0090] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, the difference being the composition of the K2O·nSiO2-based pre-reactive spinning solution.

[0091] The lamination method for the composite side window glass in this embodiment is the same as the lamination method for the composite side window glass in Embodiment 1.

[0092] Example 3

[0093] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0094] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0095] 37.12 kg tetraethyl orthosilicate, 0.1 kg nitric acid, 57.73 kg deionized water, 100 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.3 kg ammonia (20 wt%), and 4.7 kg potassium hydroxide (purity 85 wt%);

[0096] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0097] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, except that the composition of the K2O·nSiO2-based pre-reaction spinning solution is different.

[0098] The lamination method for the composite side window glass for high-speed locomotives in this embodiment is the same as the lamination method for the composite side window glass for high-speed locomotives in Embodiment 1.

[0099] Example 4

[0100] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0101] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0102] 37.12 kg tetraethyl orthosilicate, 0.4 kg nitric acid, 57.73 kg deionized water, 100 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 1.0 kg ammonia (20 wt%), and 4.7 kg potassium hydroxide (purity 85 wt%).

[0103] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0104] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, except that the composition of the K2O·nSiO2-based pre-reaction spinning solution is different.

[0105] The lamination method for the composite side window glass for high-speed locomotives in this embodiment is the same as the lamination method for the composite side window glass for high-speed locomotives in Embodiment 1.

[0106] Example 5

[0107] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0108] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0109] 37.12 kg tetraethyl orthosilicate, 0.5 kg nitric acid, 57.73 kg deionized water, 100 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 1.2 kg ammonia (20 wt%), and 4.7 kg potassium hydroxide (purity 85 wt%).

[0110] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0111] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, except that the composition of the K2O·nSiO2-based pre-reaction spinning solution is different.

[0112] The lamination method for the composite side window glass for high-speed locomotives in this embodiment is the same as the lamination method for the composite side window glass for high-speed locomotives in Embodiment 1.

[0113] Example 6

[0114] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0115] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0116] 37.12 kg tetraethyl orthosilicate, 0.3 kg nitric acid, 57.73 kg deionized water, 75 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.8 kg ammonia (20 wt%), and 4.7 kg potassium hydroxide (purity 85 wt%).

[0117] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0118] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, except that the composition of the K2O·nSiO2-based pre-reaction spinning solution is different.

[0119] The lamination method for the composite side window glass for high-speed locomotives in this embodiment is the same as the lamination method for the composite side window glass for high-speed locomotives in Embodiment 1.

[0120] Example 7

[0121] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0122] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0123] 37.12 kg tetraethyl orthosilicate, 0.3 kg nitric acid, 57.73 kg deionized water, 50 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.8 kg ammonia (20 wt%), and 4.7 kg potassium hydroxide (purity 85 wt%);

[0124] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0125] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, the difference being the composition of the K2O·nSiO2-based pre-reactive spinning solution.

[0126] The lamination method for the composite side window glass for high-speed locomotives in this embodiment is the same as the lamination method for the composite side window glass for high-speed locomotives in Embodiment 1.

[0127] Example 8

[0128] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0129] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0130] 37.12 kg tetraethyl orthosilicate, 0.3 kg nitric acid, 57.73 kg deionized water, 125 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.8 kg ammonia (20 wt%), and 4.7 kg potassium hydroxide (purity 85 wt%).

[0131] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0132] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, the difference being the composition of the K2O·nSiO2-based pre-reactive spinning solution.

[0133] The lamination method for the composite side window glass for high-speed locomotives in this embodiment is the same as the lamination method for the composite side window glass for high-speed locomotives in Embodiment 1.

[0134] Example 9

[0135] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0136] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0137] 37.12 kg tetraethyl orthosilicate, 0.3 kg nitric acid, 57.73 kg deionized water, 100 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.8 kg ammonia (20 wt%), and 4.48 kg potassium hydroxide (purity 85 wt%);

[0138] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0139] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, the difference being the composition of the K2O·nSiO2-based pre-reactive spinning solution.

[0140] The lamination method for the composite side window glass for high-speed locomotives in this embodiment is the same as the lamination method for the composite side window glass for high-speed locomotives in Embodiment 1.

[0141] Example 10

[0142] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0143] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0144] 37.12 kg tetraethyl orthosilicate, 0.3 kg nitric acid, 57.73 kg deionized water, 100 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.8 kg ammonia (20 wt%), and 4.96 kg potassium hydroxide (purity 85 wt%);

[0145] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0146] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, the difference being the composition of the K2O·nSiO2-based pre-reactive spinning solution.

[0147] The lamination method for the composite side window glass in this embodiment is the same as the lamination method for the composite side window glass in Embodiment 1.

[0148] Example 11

[0149] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0150] (1) Weigh the raw materials of the K2O·nSiO2-based pre-reaction spinning solution according to the following weights:

[0151] 37.12 kg tetraethyl orthosilicate, 0.3 kg nitric acid, 57.73 kg deionized water, 100 kg polyethanol aqueous solution (solid content: 15 wt%; molecular weight: 80,000-100,000; degree of hydrolysis: 85%-90%), 1.5 kg ethanol, 0.75 kg reactive emulsifier SE-10N, 0.8 kg ammonia (20 wt%), and 5.22 kg potassium hydroxide (purity 85 wt%);

[0152] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0153] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as that of the preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1, the difference being the composition of the K2O·nSiO2-based pre-reactive spinning solution.

[0154] The lamination method for the composite side window glass in this embodiment is the same as the lamination method for the composite side window glass in Embodiment 1.

[0155] Example 12

[0156] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0157] (1) Weigh the raw materials of the same K2O·nSiO2-based pre-reaction spinning solution as in Example 1:

[0158] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0159] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as the preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1.

[0160] The composite side window glass in this embodiment is a composite side window glass prepared by the above-mentioned PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film through the following steps:

[0161] (1) Prepare 4 pieces of 5mm thick glass, three of which are physically tempered glass and one is super strong chemically tempered glass;

[0162] (2) A first layer of PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film is laid on the ultra-strong chemically tempered glass, and a first layer of physically tempered glass is laid on the first layer of PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film; a second layer of PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film is laid on the first layer of physically tempered glass, and a second layer of PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film is laid on the first layer of physically tempered glass. A second physically tempered glass is laid on an iO2-based nanofiber / PVB interpenetrating network film; the stacked tempered glass and film layers are placed in a vacuum bag and evacuated; the vacuum bag is then placed in an autoclave and reacted at 110–115°C and 1–1.5 MPa for 0.5–1.5 hours, after which the vacuum bag is removed; high-performance molecular sieves are injected into aluminum alloy spacers, and the second and third physically tempered glass layers of the above components are bonded together using high-performance weather-resistant sealing strips, or directly using thermoplastic elastomers to bond the components to the third physically tempered glass layers; then, the hollow layer is further compressed using a hollow wire machine to obtain a hollow layer, and finally, the edges are uniformly coated with silicone weather-resistant sealant using a sealing machine to obtain a composite side window glass.

[0163] Example 13

[0164] The K2O·nSiO2-based pre-reactive spinning solution in this embodiment was prepared by the following steps:

[0165] (1) Weigh the raw materials of the same K2O·nSiO2-based pre-reaction spinning solution as in Example 1:

[0166] (2) Prepare K2O·nSiO2-based pre-reaction spinning solution using the same preparation method as in Example 1.

[0167] The preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in this embodiment is the same as the preparation method of the PVB / high modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film in Example 1.

[0168] The composite side window glass in this embodiment is a composite side window glass prepared by the above-mentioned PVB / high-modulus K2O·nSiO2-based nanofiber / PVB interpenetrating network film through the following steps:

[0169] (1) Prepare 5 pieces of 5mm thick glass, four of which are physically tempered glass and one is super strong chemically tempered glass;

[0170] (2) A first layer of PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film is laid on the ultra-strong chemically tempered glass, and a first layer of physically tempered glass is laid on the first film layer; a second layer of PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film is laid on the first layer of physically tempered glass, and a second layer of physically tempered glass is laid on the second film layer; a third layer of PVB / high-modulus K2O·nSi iO2-based nanofiber / PVB interpenetrating network film is laid on the first layer of physically tempered glass. An iO2-based nanofiber / PVB interpenetrating network film is laid on the second layer of physically tempered glass, and a third layer of physically tempered glass is laid on top of the third film layer. The stacked tempered glass and film layers are placed in a vacuum bag and evacuated. The vacuum bag is then placed in an autoclave and reacted at 110–115°C and 1–1.5 MPa for 0.5–1.5 hours. The vacuum bag is then removed. High-performance molecular sieves are injected into aluminum alloy spacers. The third and fourth layers of physically tempered glass are bonded together using high-performance weather-resistant sealing strips, or directly using thermoplastic elastomers. The glass is then further compressed using a hollow fiber press to obtain a hollow layer. Finally, the edges are uniformly coated with silicone weather-resistant sealant using a sealant applicator to obtain a composite side window glass.

[0171] Comparative Example 1

[0172] The preparation method of the composite side window glass in this comparative example is the same as that in Example 1. The difference lies in the composition of the film layer material. In this comparative example, the PVB film layer does not contain high-modulus K2O·nSiO2-based nanofibers.

[0173] Comparative Example 2

[0174] The film layer material in this comparative example was prepared through the following steps:

[0175] A 0.38 mm PVB film is immersed in a K2O·nSiO2-based pre-reaction solution with a modulus of 5. After curing, an immersion-type PVB / K2O·nSiO2 film is obtained.

[0176] The preparation method of the composite side window glass in this comparative example is the same as that of the composite side window glass in Example 1, the difference being the preparation method of the film layer material.

[0177] Fire resistance tests were conducted on the composite side window glass prepared using the film materials provided in Examples 1-13 and Comparative Examples 1-2 according to GB / T12513-2006, Fire Resistance Test Method for Glass Components. The fire resistance time of the composite side window glass was obtained. Four parallel samples were used in the experiment, and the average value of their data was taken as the experimental result. The transmittance of each composite side window glass was obtained by glass transmittance testing, and the appearance quality of each composite side window glass was obtained by visual observation. The performance parameters of the composite side window glass prepared in the embodiments and comparative examples of this invention are shown in Table 1.

[0178] Table 1 Performance parameters of composite side window glass

[0179]

[0180] *ΔT=(T t0 -T tn ) / T t0

[0181] T tn It is the transmittance after 3000 hours of ultraviolet irradiation, T t0 It is the initial transmittance.

[0182] As shown in Table 1, the composite side window glass of this invention exhibits excellent fire resistance, while the composite side window glass prepared in the comparative example fails within 20 minutes. The fire resistance of the composite side window glass of this invention is 1.5-2.5 times higher, and its transmittance and UV irradiation resistance are also significantly higher than the fire-resistant glass of the comparative example. This demonstrates that the high-modulus K₂O·nSiO₂-based nanofibers do not affect the low-temperature resistance of the PVB film, allowing for use in low-temperature (-55℃) and outdoor environments. The composite side window glass prepared in the embodiments of this invention has the advantages of being free of microbubbles, having high transmittance, long fire resistance time, and resistance to low temperatures and UV irradiation.

[0183] By comparing Examples 1-13 with Comparative Examples 1-2, it can be seen that when using the same film material, as the number of glass layers gradually decreases, the transmittance becomes better and better, the low-temperature resistance remains unchanged, and the fire resistance time gradually decreases.

[0184] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0185] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A composite structure for fire protection, characterized by, The fireproof composite structure comprises an interpenetrating network layer, an adhesive layer and a K2O·nSiO2-based nanohard fiber filling layer, wherein the K2O·nSiO2-based nanohard fiber filling layer is sandwiched between the interpenetrating network layer and the adhesive layer from inside to outside, the adhesive is polyvinyl butyral glue, and the adhesive layer is a polyvinyl butyral glue sheet layer; the K2O·nSiO2-based nanohard fiber is a hard fiber prepared by using a K2O·nSiO2-based pre-reaction spinning solution through the following steps: S101) Preparing materials according to the following components: 18-75 parts by weight of tetraethyl orthosilicate, 0.1-0.5 parts by weight of nitric acid, 30-120 parts by weight of deionized water, 50-200 parts by weight of polyvinyl alcohol aqueous solution, 1-2 parts by weight of ethanol, 0.5-1 parts by weight of reactive emulsifier SE-10N, 0.1-1.2 parts by weight of ammonia water, and 3-6 parts by weight of potassium hydroxide, wherein the solid content of the polyvinyl alcohol aqueous solution is 15 wt%, the molecular weight of the polyvinyl alcohol used to prepare the polyvinyl alcohol aqueous solution is 80000-100000, the hydrolysis degree of the polyvinyl alcohol in the polyvinyl alcohol aqueous solution is 85%-90%, the concentration of the ammonia water is 20 wt%, and the purity of the potassium hydroxide is 85 wt%; S102) Preparing a first mixed solution: mixing the tetraethyl orthosilicate, the nitric acid and the deionized water and stirring at room temperature for at least 60 min, and then stirring for another 60 min after a silica sol with a multimodal and wide distribution of particle sizes of 40-360 nm is formed in the mixture, thereby obtaining the first mixed solution; S103) Adding the polyvinyl alcohol aqueous solution, the ethanol and the reactive emulsifier SE-10N into the first mixed solution and stirring at room temperature for at least 60 min, thereby obtaining a second mixed solution with a viscosity of 100-300 mPa·s; S104) Slowly adding the ammonia water into the second mixed solution and stirring at room temperature for at least 60 min, thereby obtaining a third mixed solution with a pH value of 6-7; S105) Stepwise adding the potassium hydroxide into the third mixed solution and keeping the temperature of the solution system below 25℃, and then vacuum defoaming for 60 min, thereby obtaining a K2O·nSiO2-based pre-reaction spinning solution with a viscosity of 350-800 mPa·s; S106) Using the K2O·nSiO2-based pre-reaction spinning solution to spin and obtain the K2O·nSiO2-based nanohard fiber; The specific steps for preparing the fireproof composite structure are as follows: Placing the K2O·nSiO2-based nanofiber membrane between two polyvinyl butyral glue sheets and hot pressing to obtain the fireproof composite structure.

2. The fireproof composite structure according to claim 1, wherein The thickness of the polyvinyl butyral glue sheet layer is 0.3-1.5 mm.

3. A composite side window, characterized by The composite material structure comprises m layers of super-strong chemically tempered glass, n layers of physically tempered glass, adhesive layers, hollow layers and a layer of anti-splashing layer, m is an integer greater than or equal to 1, n is an integer greater than or equal to 2; when m is equal to 1, at least the super-strong chemically tempered glass and the first layer of the physically tempered glass or the two adjacent layers of the physically tempered glass are connected by the adhesive layer; when m is greater than 1, at least the two adjacent layers of the super-strong chemically tempered glass or the super-strong chemically tempered glass and the first layer of the physically tempered glass or the two adjacent layers of the physically tempered glass are connected by the adhesive layer; wherein at least one of the adhesive layers is made of the fireproof composite material structure of claim 1.

4. The composite side window of claim 3, wherein The surface stress of the super-strong chemically tempered glass is 400-900 MPa and the stress layer depth is 20-50 μm, and the thickness of the super-strong chemically tempered glass is 3-10 mm.

Images