Heat-insulating and high-temperature-resistant metal core fireproof plate and preparation method thereof

Abstract

The invention discloses a heat-insulating and high-temperature-resistant metal core fireproof plate and a preparation method thereof, belongs to the technical field of plate processing, and is used for solving the technical problem that the structural stability and fireproof performance of a fireproof plate in the prior art need to be further improved. The fireproof board comprises the two composite framework layers and the metal plate core layer arranged between the composite framework layers, in the process of preparing the fireproof board, aerogel and honeycomb polyimide resin are closely crosslinked through chemical bonds, in the supercritical drying process, the aerogel invades into gaps of a felt board to be solidified and closely combined with the felt board, and the fireproof board is formed. The aerogel layer serves as a heat insulation and sound insulation layer and is connected with all the layers at the same time, the honeycomb layer enhances the pressure resistance of the fireproof plate, all the layers are matched with one another in structure, and the fireproof plate which is flame-retardant, heat-insulation, bending-resistant, high-temperature-resistant, impact-resistant and stable is obtained.

Description

Technical Field

[0001] The invention relates to the technical field of plate processing, and in particular to a heat-insulating and high-temperature-resistant metal core fireproof plate and a preparation method thereof. Background Art

[0002] The development history of fireproof panels can be divided into several stages. The earliest gypsum board was the main fireproof material, but it performed poorly in humid environments. With the introduction of fiber cement board, cellulose and cement were combined to improve fire resistance and durability, and adapt to more complex application environments. Modern fireproof panels tend to use composite materials, such as composite fireproof panels and honeycomb structures, to provide higher strength, lightweight characteristics and excellent fireproof performance. Composite fireproof panels combine the advantages of different materials, such as fireproof gypsum and mineral wool, to increase their mechanical strength and waterproof properties. Honeycomb structures use honeycomb core materials (such as paper honeycombs or aluminum honeycombs) to provide lightweight and high-strength fireproof performance. This structure is widely used in aerospace and high-end buildings. Future development trends include the use of new composite materials, nanomaterials and environmentally friendly recyclable materials to further improve fireproof performance and sustainability.

[0003] In the prior art, patent document CN104944846A discloses a compression-resistant fireproof board and a preparation method thereof. The compression-resistant fireproof board is composed of the following ingredients by weight: 8-13 parts of glass beads, 4-9 parts of mineral wool, 14-22 parts of vermiculite powder, 3-8 parts of bisphenol S epoxy resin, 9-14 parts of hydroxypropyl methylcellulose, 5-8 parts of aluminum oxide, 3-6 parts of nickel oxide, 10-16 parts of tetraethyl orthosilicate, and 0.6-1.5 parts of tributyl phosphate. It specifically includes the steps of crushing, mixing, and hot pressing. The prepared fireproof board has the advantages of high fire resistance and high compressive strength.

[0004] The above patent content is to prepare the fireproof board by mixing and hot pressing a plurality of flame retardant materials. However, the flame retardant materials include organic materials and inorganic materials. Due to the large difference in polarity between the materials, the structural stability of the fireproof board is poor, which affects the performance of the fireproof board. At the same time, mineral wool is used as a compressive flame retardant component. Due to the poor resilience of mineral wool, irreversible deformation after extrusion will further cause the structure of the fireproof board to change, resulting in further reduction of fireproof performance.

[0005] In summary, the structural stability and fireproof performance of the fireproof board obtained by simply blending flame retardant components and hot pressing need to be further improved. In view of the technical defects in this regard, a solution is now proposed. Summary of the invention

[0006] The purpose of the present invention is to provide a heat-insulating and high-temperature-resistant metal core fireproof board and a preparation method thereof, so as to solve the technical problem that the structural stability and fireproof performance of the fireproof board in the prior art need to be further improved.

[0007] The object of the present invention can be achieved by the following technical solution: A heat-insulating and high-temperature-resistant metal core fireproof board material, comprising two composite structure layers and a metal plate core layer arranged between the composite structure layers;

[0008] The forming method of the composite structure layer includes the following steps:

[0009] The composite framework layer is obtained by processing the following steps:

[0010] A1. Place the felt layer in a molding mold, lay a honeycomb polyimide resin on the top of the felt layer, and then use a hot press to heat press. The temperature of the hot press is set to 100-120°C, and the pressure is set to 8-12MPa. Inject a modified silica aerogel precursor into the molding mold until it covers the top of the honeycomb polyimide resin, drip 0.8-1.6wt% zinc chloride solution into the mold, and let it stand for 2-4h to obtain a composite structure layer precursor;

[0011] A2. Place the mold in a salt bath furnace, exhaust the air in the autoclave with carbon dioxide gas, and then use a booster to introduce 15-18MPa carbon dioxide gas into the autoclave. The temperature of the salt bath furnace rises to 40-50°C. During the heating process, observe the internal pressure of the autoclave, use valves on both sides to vent and release the pressure, control the pressure in the autoclave to be less than 18MPa, and keep the reaction warm for 1-2h to obtain a composite framework layer consisting of a felt layer cross-linked with modified silica aerogel and a support layer.

[0012] Furthermore, in step A1, the felt layer is processed from a felt board, which is one of glass fiber felt, aluminum silicate fiber felt and ceramic fiber felt, and the volume of the added 0.8-1.6wt% zinc chloride solution is 1-3% of the modified silica aerogel precursor.

[0013] Furthermore, the metal plate core layer is prepared by cutting and spin-coating a metal alloy plate with epoxy resin, and the metal alloy plate is one of a nickel-based alloy, a chromium-nickel alloy and a tungsten-copper alloy.

[0014] Furthermore, the preparation method of the honeycomb polyimide resin comprises the following steps:

[0015] B1. Add 2-vinyl-4,6-diamino-1,3,5-triazine, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, triethylamine and dimethyl sulfoxide into a reaction kettle, raise the temperature of the reaction kettle to 60-80° C., and keep the temperature for 2-4 hours to obtain a polyamide solution;

[0016] The reaction equation for preparing polyamide solution is:

[0017]

[0018] Where:

[0019] The reaction principle for preparing the polyamide solution is as follows: under alkaline conditions, the anhydride group and the amino group undergo a ring-opening reaction to form an amide, and then a polymerization reaction continues to occur to obtain a polyamide solution.

[0020] B2. After the polyamide solution is poured into the honeycomb mold, the mold is placed in a freeze dryer, the temperature of the freeze dryer is lowered to -40 to -60°C, and after being kept warm for 20 to 40 minutes, the temperature is raised to 0 to 10°C, and vacuum dried until the mold has a constant weight, to obtain a polyamide resin;

[0021] B3. Add the mold into a tubular furnace, introduce nitrogen protection, heat the tubular furnace to 270±5°C at a heating rate of 5°C / min, and keep the temperature for 2-4h to obtain a polyimide resin;

[0022] The reaction equation for preparing polyimide resin is:

[0023]

[0024] Where:

[0025] B4, after the polyamide-imide gel is peeled off from the mold, it is placed on a hot press at a temperature of 300-350° C., and high-temperature compression is performed for 20-30 minutes, and a honeycomb polyimide resin precursor is obtained by post-processing;

[0026] B5. Add the oxidizing solution into the oil bath. After the temperature of the oil bath rises to 50-60° C., completely immerse the honeycomb polyimide resin precursor in the oxidizing solution and keep it warm for 30-40 minutes. Then, perform post-treatment to obtain the honeycomb polyimide resin.

[0027] The reaction equation for preparing honeycomb polyimide resin is:

[0028]

[0029] Where:

[0030] The reaction principle for preparing the honeycomb polyimide resin is as follows: acetic acid and hydrogen peroxide first react to form peracid, and under the catalysis of the peracid, the carbon-carbon double bonds in the organic structure are oxidized to form epoxy groups to obtain the honeycomb polyimide resin.

[0031] Further, in step B1, the amount ratio of 2-vinyl-4,6-diamino-1,3,5-triazine, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, triethylamine and dimethyl sulfoxide is 2-4 g:3-5 g:0.1-0.2 g:20-30 mL; in step B4, the pressure is 4-6 GPa, and the post-treatment includes: placing the polyimide aerogel in a stretching machine, controlling the longitudinal stretching ratio to 4-6:1, the transverse stretching ratio to 4-6:1, maintaining the tension, raising the temperature of the stretching machine to 300-400 ° C, and maintaining The polyimide honeycomb layer precursor is treated at room temperature for 0.5 to 1 h to obtain a honeycomb polyimide resin precursor; in step B5, the oxidizing liquid is obtained by mixing acetic acid, hydrogen peroxide and N,N-dimethylformamide, wherein the amount ratio of acetic acid, hydrogen peroxide and N,N-dimethylformamide is 1 to 2 g: 1 to 2 g: 20 to 30 mL, and the post-treatment includes: using a sampler to take the polyimide honeycomb layer precursor out of the oil bath, washing it with ethanol for 3 to 5 times, and then spreading the polyimide honeycomb layer precursor in a drying oven at a temperature of 60 to 80 ° C and vacuum drying it until the material has a constant weight to obtain a honeycomb polyimide resin.

[0032] Furthermore, the preparation method of the modified silica aerogel precursor comprises the following steps:

[0033] C1. Add bis(triethoxysilyl)methane and anhydrous ethanol into a reactor and stir at a stirring rate of 240 to 360 rpm. After stirring for 5 to 10 minutes, add saturated acetic acid aqueous solution into the reactor. While stirring, raise the temperature of the reactor to 60 to 80° C. and keep the temperature for 2 to 4 hours to obtain a silica sol solution.

[0034] Reaction equation:

[0035] Si(OR) 4 +4H 2 O→Si(OH) 4 +4ROH

[0036] n Si(OH) 4 →(SiO 2 ) n +2nH 2 O

[0037] Reaction principle: Under the catalysis of acetic acid, the silanol is hydrolyzed to produce silanol, which further undergoes polycondensation. In this process, the colloidal SiO 2 The particles gradually aggregate to form larger particles. As the reaction proceeds, these particles further develop into nanoscale clusters. Subsequently, these clusters cross-link with each other to form a gel with a nanoscale network structure.

[0038] C2, adding the silica sol solution into the reactor and stirring, the stirring rate is set to 60-80 rpm, and saturated ammonia water is added dropwise during the stirring process to adjust the pH value of the system to 8-9. After the adjustment is completed, stirring is continued for 5-10 minutes, and the silica gel is obtained by post-treatment;

[0039] C3. Soak the silica gel in an ethanol solution, let it stand for 6 hours, then place it in a drying oven at 80° C. and dry it for 20 to 30 minutes. Repeat the soaking and drying operation 3 to 5 times to obtain a modified silica aerogel precursor.

[0040] Furthermore, in step C1, the dosage ratio of bis(triethoxysilyl)methane, anhydrous ethanol and saturated acetic acid aqueous solution is 2-4 g: 2-3 g: 3-5 g; in step C2, the post-treatment operation includes: after the stirring is completed, placing the solution in a drying oven at a temperature of 60° C. and vacuum drying until the system has a constant weight, and continuing vacuum drying for 2-3 hours to obtain silica gel.

[0041] Furthermore, the felt board layer is processed from a felt board, and the felt board is one of a glass fiber felt board, an aluminum silicate fiber felt board and a ceramic fiber felt board.

[0042] Furthermore, the metal plate core layer is prepared by cutting and spin-coating a metal alloy plate with epoxy resin, and the metal alloy plate is one of a nickel-based alloy, a chromium-nickel alloy and a tungsten-copper alloy.

[0043] The present invention also provides a method for preparing a heat-insulating and high-temperature-resistant metal core fireproof board, comprising the following steps:

[0044] S1, take a metal plate cut by a CNC machine tool and having the same size as the composite structure layer, spin-coat a layer of epoxy resin on the upper and lower surfaces of the metal plate, and obtain a metal plate core layer after high-temperature curing;

[0045] S2. Spin-coat 0.8-1.6 wt% zinc chloride solution on the core layer of the metal plate, take two composite framework layers, and respectively attach their support layers to the upper and lower surfaces of the metal plate to obtain a fireproof plate precursor, put the fireproof plate precursor into a punching machine, and punch at a pressure of 200 MPa for 1-2 hours to obtain a fireproof plate.

[0046] The present invention has the following beneficial effects:

[0047] 1. In the process of preparing a heat-insulating and high-temperature resistant metal core fireproof board of the present invention, a honeycomb polyimide resin and a modified silica aerogel precursor are first prepared, wherein the surface of the honeycomb polyimide resin is modified to contain rich epoxy groups, and in the process of preparing the fireproof board, the rich hydroxyl groups on the surface of the modified silica aerogel precursor fully react with the epoxy groups on the surface of the honeycomb polyimide resin to make the two tightly combined, and further in the process of supercritical drying, the modified silica aerogel precursor is dried and cured to form an aerogel layer, wherein the aerogel components in the gaps of the felt board improve the mechanical properties of the felt board after curing, and the felt board layer, the honeycomb layer and the aerogel layer are tightly combined to form a composite structure, wherein the rich hydroxyl structure on the surface of the aerogel layer is cross-linked with the surface of the metal board coated with epoxy resin, and finally a flame-retardant, heat-insulating, bending-resistant, high-temperature resistant, impact-resistant and stable fireproof board is prepared.

[0048] 2. The fireproof board prepared by the present invention has a rich hierarchical structure, and the hierarchical structures are connected by the modified silica aerogel prepared by the present invention, thereby ensuring the stability between the structures. The modified silica aerogel improves the heat insulation and sound insulation capabilities of the board due to its rich void structure. In order to improve the impact resistance of the board, the aerogel layer is partially embedded in a honeycomb layer structure composed of modified polyamide resin. The honeycomb layer design effectively disperses the stress between the structures, improves the stability and strength of the fireproof board structure, and cooperates with the modified silica aerogel to improve the high temperature resistance and impact resistance of the board.

[0049] 3. In the process of preparing honeycomb polyimide resin of the present invention, the reaction monomers are selected from 2-vinyl-4,6-diamino-1,3,5-triazine and bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, both of which have carbon-carbon double bonds, which lay the foundation for the subsequent reaction modification to produce epoxy groups and closely combine with aerogels. Among them, the 2-vinyl-4,6-diamino-1,3,5-triazine component absorbs a large amount of heat at high temperature to release gases such as nitrogen and ammonia, which are released through the rich void structure inside the aerogel, taking away a large amount of heat to further improve the thermal insulation capacity of the fireproof board; after thermal imidization treatment, the organic material forms a more complex three-dimensional structure to form a polyimide gel, and then the impact resistance of the material is further improved by high-temperature compression, and the thermal expansion coefficient is further reduced after high-temperature stretching and curing, and the high temperature resistance is further enhanced. Finally, after peroxyacid oxidation, a honeycomb polyimide resin rich in epoxy groups on the surface is obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0051] Figure 1 It is a schematic diagram of the overall three-dimensional structure of the present invention;

[0052] Figure 2 It is a schematic diagram of the composite of the support layer and the felt board layer of the present invention;

[0053] In the figure: 100, felt board layer; 200, support layer; 300, metal board core layer. DETAILED DESCRIPTION

[0054] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] Example 1

[0056] This embodiment is used to provide a method for preparing a heat-insulating and high-temperature resistant metal core fireproof board, comprising the following steps:

[0057] S1. Preparation of honeycomb polyimide resin

[0058] Weigh: 9.0 g of 2-vinyl-4,6-diamino-1,3,5-triazine, 12.0 g of bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 0.5 g of triethylamine and 60 mL of dimethyl sulfoxide into a reaction kettle, raise the temperature of the reaction kettle to 60° C., and keep the temperature for 2 hours to obtain a polyamide solution;

[0059] After the polyamide solution is poured into the honeycomb mold, the mold is placed in a freeze dryer, the temperature of the freeze dryer is lowered to -40°C, and after keeping warm for 20 minutes, the temperature is raised to 10°C, and vacuum dried until the mold has a constant weight, thereby obtaining a polyamide resin;

[0060] The mold was placed in a tubular furnace, nitrogen was introduced for protection, the temperature of the tubular furnace was raised to 275°C at a rate of 5°C / min, and the temperature was kept for reaction for 2 hours to obtain a polyimide resin;

[0061] After the polyamide-imide gel is peeled off from the mold, it is placed on a hot press at a temperature of 300°C and compressed at a high temperature for 20 minutes at a pressure of 4 GPa. The polyimide aerogel is placed in a stretching machine, and the longitudinal stretching ratio is controlled to be 4:1. After the transverse stretching ratio is 4:1, the tension is maintained, and the temperature of the stretching machine is increased to 300°C, and the heat preservation treatment is performed for 0.5 hours to obtain a honeycomb polyimide resin precursor;

[0062] Weigh: 3.0 g acetic acid, 3.0 g hydrogen peroxide and 60 mL N,N-dimethylformamide, add into the reaction kettle and stir, set the temperature of the reaction kettle to 50°C, and stir at a rate of 120 rpm to obtain an oxidation solution;

[0063] The oxidizing solution is added into the oil bath. After the temperature of the oil bath is raised to 50°C, the honeycomb polyimide resin precursor is completely immersed in the oxidizing solution. After being kept warm and soaked for 30 minutes, the polyimide honeycomb layer precursor is taken out from the oil bath using a sampler. After being washed with ethanol three times, the polyimide honeycomb layer precursor is spread flat in a drying oven at a temperature of 60°C and vacuum dried until the material reaches a constant weight to obtain a honeycomb polyimide resin.

[0064] S2. Preparation of modified silica aerogel precursor

[0065] Add bis(triethoxysilyl)methane and anhydrous ethanol into a reactor and stir at a stirring rate of 240 rpm. After stirring for 5 minutes, add saturated acetic acid aqueous solution into the reactor. While stirring, raise the temperature of the reactor to 60° C. and keep the temperature for 2 hours to obtain a silica sol solution.

[0066] The silica sol solution was added into the reactor and stirred at a stirring rate of 60 rpm. During the stirring process, saturated ammonia water was added dropwise to adjust the pH value of the system to 8. After the adjustment, the stirring was continued for 5 min. After the stirring was completed, the solution was placed in a drying oven at a temperature of 60° C. and vacuum dried until the system had a constant weight. The vacuum drying was continued for 2 h to obtain silica gel.

[0067] The silica gel was immersed in an ethanol solution, allowed to stand for 6 hours, and then placed in a drying oven at a temperature of 80° C. for 20 minutes. The immersion and drying were repeated three times to obtain a modified silica aerogel precursor.

[0068] S3. Preparation of fireproof panels

[0069] The felt layer 100 is placed in a molding mold, and a honeycomb polyimide resin is laid on the top of the felt layer 100, and then hot-pressed using a hot press. The temperature of the hot press is set to 100°C, and the pressure is set to 8MPa. A modified silica aerogel precursor is injected into the molding mold until it covers the top of the honeycomb polyimide resin. A 0.8wt% zinc chloride solution of 1.0% of the volume of the modified silica aerogel precursor is dripped into the mold. After standing for 2 hours, a composite structure precursor is obtained.

[0070] The mold was placed in a salt bath furnace, and after exhausting the air in the autoclave with carbon dioxide gas, 15MPa carbon dioxide gas was introduced into the autoclave using a pressurizing device. The temperature of the salt bath furnace rose to 40°C. During the heating process, the internal pressure of the autoclave was observed, and the valves on both sides were used to vent and release the pressure. The pressure in the autoclave was controlled to be less than 18MPa, and the reaction was kept warm for 1 hour to obtain a composite structure layer consisting of a felt layer 100 cross-linked with modified silica aerogel and a support layer 200.

[0071] Take a metal plate that has been cut by a CNC machine tool and is the same size as the composite structure layer, spin-coat a layer of epoxy resin on the upper and lower surfaces of the metal plate, and obtain a metal plate core layer 300 after high-temperature curing. Spin-coat 0.8wt% zinc chloride solution on the metal plate core layer 300, take two composite structure layers, and attach their support layers 200 to the upper and lower surfaces of the metal plate respectively to obtain a fireproof plate precursor, put the fireproof plate precursor into a stamping machine, and stamp it at a pressure of 200MPa for 1h to obtain a fireproof plate.

[0072] Example 2

[0073] This embodiment is used to provide a method for preparing a heat-insulating and high-temperature resistant metal core fireproof board, comprising the following steps:

[0074] S1. Preparation of honeycomb polyimide resin

[0075] Weigh: 12.0 g of 2-vinyl-4,6-diamino-1,3,5-triazine, 12.0 g of bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 0.6 g of triethylamine and 75 mL of dimethyl sulfoxide into a reaction kettle, raise the temperature of the reaction kettle to 80° C., and keep the temperature for 4 hours to obtain a polyamide solution;

[0076] After the polyamide solution is poured into the honeycomb mold, the mold is placed in a freeze dryer, the temperature of the freeze dryer is lowered to -60°C, and after keeping warm for 40 minutes, the temperature is raised to 5°C, and vacuum dried until the mold has a constant weight, thereby obtaining a polyamide resin;

[0077] The mold was placed in a tubular furnace, nitrogen was introduced for protection, the temperature of the tubular furnace was increased to 265°C at a rate of 5°C / min, and the temperature was kept for reaction for 2 hours to obtain a polyimide resin;

[0078] After the polyimide gel is peeled off from the mold, it is placed on a hot press at a temperature of 350°C and compressed at a high temperature for 30 minutes at a pressure of 6 GPa. The polyimide aerogel is placed in a stretching machine, and the longitudinal stretching ratio is controlled to be 6:1. After the transverse stretching ratio is 6:1, the tension is maintained, and the temperature of the stretching machine is increased to 400°C. The heat treatment is carried out for 1 hour to obtain a honeycomb polyimide resin precursor.

[0079] Weigh: 4.5 g of acetic acid, 4.5 g of hydrogen peroxide and 75.0 mL of N,N-dimethylformamide, add them into a reactor and stir. The temperature of the reactor is set to 50° C. and the stirring rate is 120 rpm to obtain an oxidation solution.

[0080] The oxidizing solution is added into the oil bath. After the temperature of the oil bath is raised to 50°C, the honeycomb polyimide resin precursor is completely immersed in the oxidizing solution. After being kept warm and soaked for 30 minutes, the polyimide honeycomb layer precursor is taken out from the oil bath using a sampler. After being washed with ethanol three times, the polyimide honeycomb layer precursor is spread flat in a drying oven at a temperature of 60°C and vacuum dried until the material reaches a constant weight to obtain a honeycomb polyimide resin.

[0081] S2. Preparation of modified silica aerogel precursor

[0082] Weigh: 12.0 g of bis(triethoxysilyl)methane and 9.0 g of anhydrous ethanol were added to a reactor and stirred at a stirring rate of 360 rpm. After stirring for 10 min, 9.0 g of a saturated acetic acid aqueous solution was added to the reactor. While stirring, the temperature of the reactor was raised to 80° C. and the reaction was kept warm for 4 h to obtain a silica sol solution.

[0083] The silica sol solution was added into the reactor and stirred at a stirring rate of 80 rpm. During the stirring process, saturated ammonia water was added dropwise to adjust the pH value of the system to 9. After the adjustment, the stirring was continued for 10 min. After the stirring was completed, the solution was placed in a drying oven at a temperature of 60° C. and vacuum dried until the system had a constant weight. The vacuum drying was continued for 3 h to obtain silica gel.

[0084] The silica gel was immersed in an ethanol solution, allowed to stand for 6 hours, and then placed in a drying oven at a temperature of 80° C. for 30 minutes. The immersion and drying were repeated 5 times to obtain a modified silica aerogel precursor.

[0085] S3. Preparation of fireproof panels

[0086] Take two felt boards and honeycomb polyimide resins that are cut by a CNC cutting machine and have the same shape and size, lay the felt board flat on a rectangular mold with a bottom that is the same shape and size as the felt board, continue to lay the honeycomb polyimide resin on the surface of the felt board, use a hot press to make the felt board and the polyimide honeycomb layer fit tightly, pour the modified silica aerogel precursor into the mold until the honeycomb polyimide resin is filled, continue to drip 2.0% of the volume of the modified silica aerogel precursor into the mold. After standing for 2 hours, a composite structure precursor is obtained;

[0087] The felt layer 100 is placed in a molding mold, and a honeycomb polyimide resin is laid on the top of the felt layer 100 and then hot-pressed using a hot press. The temperature of the hot press is set to 120° C. and the pressure is set to 12 MPa. A modified silica aerogel precursor is injected into the molding mold until it covers the top of the honeycomb polyimide resin. A 1.6 wt % zinc chloride solution of 2.0% of the volume of the modified silica aerogel precursor is dripped into the mold. After standing for 2 hours, a composite structure precursor is obtained.

[0088] The mold is placed in a salt bath furnace, and after exhausting the air in the autoclave with carbon dioxide gas, 18MPa carbon dioxide gas is introduced into the autoclave using a pressurizing device. The temperature of the salt bath furnace rises to 50°C. During the heating process, the internal pressure of the autoclave is observed, and the valves on both sides are used to vent and release the pressure. The pressure in the autoclave is controlled to be less than 18MPa, and the reaction is kept warm for 2 hours to obtain a composite structure layer consisting of a felt layer 100 cross-linked with modified silica aerogel and a support layer 200.

[0089] Take a metal plate that has been cut by a CNC machine tool and is the same size as the composite structure layer, spin-coat a layer of epoxy resin on the upper and lower surfaces of the metal plate, and obtain a metal plate core layer 300 after high-temperature curing. Spin-coat 0.8wt% zinc chloride solution on the metal plate core layer 300, take two composite structure layers, and attach their support layers 200 to the upper and lower surfaces of the metal plate respectively to obtain a fireproof plate precursor, put the fireproof plate precursor into a stamping machine, and stamp it at a pressure of 200MPa for 2h to obtain a fireproof plate.

[0090] Example 3

[0091] This embodiment is used to provide a method for preparing a heat-insulating and high-temperature resistant metal core fireproof board, comprising the following steps:

[0092] S1. Preparation of honeycomb polyimide resin

[0093] Weigh: 9.0 g of 2-vinyl-4,6-diamino-1,3,5-triazine, 12.0 g of bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 0.5 g of triethylamine and 75 mL of dimethyl sulfoxide into a reaction kettle, raise the temperature of the reaction kettle to 70° C., and keep the temperature for 3 hours to obtain a polyamide solution;

[0094] After the polyamide solution is poured into the honeycomb mold, the mold is placed in a freeze dryer, the temperature of the freeze dryer is lowered to -50°C, and after being kept warm for 30 minutes, the temperature is raised to 5°C, and vacuum dried until the mold has a constant weight, thereby obtaining a polyamide resin;

[0095] The mold was placed in a tubular furnace, nitrogen was introduced for protection, the temperature of the tubular furnace was increased to 270°C at a rate of 5°C / min, and the temperature was kept for reaction for 3 hours to obtain a polyimide resin;

[0096] After the polyimide aerogel was peeled off from the mold, it was placed on a hot press at a temperature of 320°C and compressed at a high temperature for 25 minutes at a pressure of 5 GPa. The polyimide aerogel was placed in a stretching machine, and the longitudinal stretching ratio was controlled to be 5:1. After the transverse stretching ratio was 5:1, the tension was maintained, and the temperature of the stretching machine was increased to 350°C. The heat preservation treatment was performed for 1 hour to obtain a honeycomb polyimide resin precursor.

[0097] Weigh: 3.0 g acetic acid, 3.0 g hydrogen peroxide and 75.0 mL N,N-dimethylformamide, add into the reaction kettle and stir, set the temperature of the reaction kettle to 50° C., stir at a rate of 120 rpm, and obtain an oxidation solution;

[0098] The oxidizing solution is added into the oil bath. After the temperature of the oil bath is raised to 60°C, the honeycomb polyimide resin precursor is completely immersed in the oxidizing solution. After being kept warm and soaked for 30 minutes, the polyimide honeycomb layer precursor is taken out from the oil bath using a sampler. After being washed with ethanol three times, the polyimide honeycomb layer precursor is spread flat in a drying oven at a temperature of 60°C and vacuum dried until the material has a constant weight to obtain a honeycomb polyimide resin.

[0099] S2. Preparation of modified silica aerogel precursor

[0100] Weigh; 12.0 g of bis(triethoxysilyl)methane and 9.0 g of anhydrous ethanol were added to a reactor and stirred at a stirring rate of 300 rpm. After stirring for 8 min, 12.0 g of a saturated aqueous acetic acid solution was added to the reactor. While stirring, the temperature of the reactor was raised to 70° C. and the reaction was kept warm for 3 h to obtain a silica sol solution;

[0101] The silica sol solution was added to the reactor and stirred at a stirring rate of 70 rpm. During the stirring process, saturated ammonia water was added dropwise to adjust the pH value of the system to 9. After the adjustment, stirring was continued for 8 minutes. After the stirring was completed, the solution was placed in a drying oven at a temperature of 60° C. and vacuum dried until the system had a constant weight. The vacuum drying was continued for 3 hours to obtain silica gel.

[0102] The silica gel was immersed in an ethanol solution, allowed to stand for 6 hours, and then placed in a drying oven at a temperature of 80° C. for 25 minutes. The immersion and drying were repeated 4 times to obtain a modified silica aerogel precursor.

[0103] S3. Preparation of fireproof panels

[0104] The felt layer 100 is placed in a molding mold, and a honeycomb polyimide resin is laid on the top of the felt layer 100, and then hot-pressed using a hot press. The temperature of the hot press is set to 110° C., and the pressure is set to 10 MPa. A modified silica aerogel precursor is injected into the molding mold until it covers the top of the honeycomb polyimide resin. A 1.2 wt % zinc chloride solution of 3.0% of the volume of the modified silica aerogel precursor is dripped into the mold. After standing for 2 hours, a composite structure precursor is obtained.

[0105] The mold is placed in a salt bath furnace, and after exhausting the air in the autoclave with carbon dioxide gas, 16MPa carbon dioxide gas is introduced into the autoclave using a booster device, and the temperature of the salt bath furnace rises to 45°C. During the heating process, the internal pressure of the autoclave is observed, and the valves on both sides are used to release the gas and pressure, and the pressure in the autoclave is controlled to be less than 18MPa. The reaction is kept warm for 2 hours to obtain a composite framework layer consisting of a felt layer 100 cross-linked with modified silica aerogel and a support layer 200;

[0106] Take a metal plate that has been cut by a CNC machine tool and is the same size as the composite structure layer, spin-coat a layer of epoxy resin on the upper and lower surfaces of the metal plate, and obtain a metal plate core layer 300 after high-temperature curing. Spin-coat 1.2wt% zinc chloride solution on the metal plate core layer 300, take two composite structure layers, and attach their support layers 200 to the upper and lower surfaces of the metal plate respectively to obtain a fireproof plate precursor, put the fireproof plate precursor into a stamping machine, and stamp it at a pressure of 200MPa for 2h to obtain a fireproof plate.

[0107] Comparative Example 1

[0108] The difference between this comparative example and Example 3 is that step S1 is omitted, and in step S3, the use of honeycomb polyimide resin is omitted.

[0109] Comparative Example 2

[0110] The difference between this comparative example and Example 3 is that step S2 is eliminated, and in step S3, an equal amount of expanded graphite is used to replace the modified silica aerogel.

[0111] Comparative Example 3

[0112] The difference between this comparative example and Example 3 is that in step S1, no mold is used to prepare the honeycomb material, and in step S3, an equal amount of plate-like polyimide sheet material is used to replace the honeycomb polyimide resin.

[0113] Performance testing:

[0114] The combustion grade and thermal conductivity of the fireproof panels prepared in Examples 1-3 and Comparative Examples 1-3 were tested with reference to the standard JG / T 564-2018 "Ceramic Fiber Fireproof Panels for Buildings";

[0115] The bending strength, thermal expansion coefficient, impact resistance and roller peel strength of the fireproof panels prepared in Examples 1-3 and Comparative Examples 1-3 were tested with reference to the standard JC / T 2561-2020 "Non-combustible metal composite panels for architectural decoration";

[0116] The sound insulation performance of the fireproof panels prepared in Examples 1-3 and Comparative Examples 1-3 was tested with reference to the standard FZ / T 64058-2016 “Reprocessed fiber felt for automotive sound insulation and heat insulation pads”. The specific data are shown in Table 1.

[0117] Table 1-Performance test data of each sample

[0118]

[0119]

[0120] Data Analysis:

[0121] Comparing and analyzing the data in Table 1 above, the fireproof board prepared by the present invention has a combustion grade of A and a thermal conductivity of 0.038 W·(m·K). -1 , bending strength is 124MPa, thermal expansion coefficient is 3.64×10 -5 ℃ -1 , impact resistance is 58kg·cm, average roller peel strength is 118N·m -1 , minimum roller peeling strength is 108N·m -1 At the same time, the sound absorption coefficients at frequencies of 800Hz, 1250Hz, 2000Hz and 3150Hz are 0.14, 0.28, 0.56 and 0.82 respectively, and all performances are better than those of the comparative example;

[0122] It is explained that the interior of the fireproof board prepared by the present invention uses the heat-insulating and sound-insulating aerogel as a cross-linked structure, and before supercritical drying, the abundant hydroxyl groups on its surface react with the epoxy groups on the surface of the heat-insulating and fire-proof honeycomb polyimide resin to form a tight cross-linked structure. The honeycomb hierarchical structure shares the load of the aerogel and improves the impact resistance of the structure. During the supercritical drying process, the aerogel further invades the gaps in the felt board, thereby improving the flame retardancy and mechanical properties of the fireproof and heat-insulating felt board and forming a tight structure. Finally, it reacts with the metal board coated with epoxy resin on the surface, and forms a tight bond through chemical bond cross-linking, thereby ensuring the structural stability of the metal board. Finally, a flame-retardant, heat-insulating, anti-bending, high-temperature resistant, impact-resistant and stable fireproof board is prepared.

[0123] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

[0124] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0125] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A heat-insulating and high-temperature-resistant metal core fireproof board, characterized in that: It comprises two composite structure layers and a metal plate core layer (300) arranged between the composite structure layers; The composite framework layer is obtained by processing the following steps: A1. placing a felt board layer (100) in a molding mold, laying a honeycomb polyimide resin on the top of the felt board layer (100), and then hot pressing using a hot press, wherein the temperature of the hot press is set to 100-120° C., and the pressure is set to 8-12 MPa, injecting a modified silica aerogel precursor into the molding mold until the top of the honeycomb polyimide resin is covered, dripping a 0.8-1.6 wt % zinc chloride solution into the mold, and letting it stand for 2-4 hours to obtain a composite structure layer precursor; A2. Place the mold in a salt bath furnace, exhaust the air in the autoclave with carbon dioxide gas, and then use a booster to introduce 15-18 MPa carbon dioxide gas into the autoclave. The temperature of the salt bath furnace rises to 40-50° C. During the heating process, observe the internal pressure of the autoclave, use valves on both sides to release gas and pressure, control the pressure in the autoclave to be less than 18 MPa, and keep the temperature for 1-2 hours to obtain a composite structure layer consisting of a felt layer (100) cross-linked with a modified silica aerogel and a support layer (200).

2. The heat-insulating and high-temperature-resistant metal core fireproof board according to claim 1, characterized in that: In step A1, the felt layer (100) is processed from a felt, wherein the felt is one of a glass fiber felt, an aluminum silicate fiber felt and a ceramic fiber felt, and the volume of the 0.8-1.6 wt % zinc chloride solution added dropwise is 1-3% of the modified silica aerogel precursor.

3. The heat-insulating and high-temperature-resistant metal core fireproof board according to claim 1, characterized in that: The metal plate core layer (300) is prepared by cutting a metal alloy plate and spin-coating epoxy resin, and the metal alloy plate is one of a nickel-based alloy, a chromium-nickel alloy and a tungsten-copper alloy.

4. The heat-insulating and high-temperature-resistant metal core fireproof board according to claim 1, characterized in that: The preparation method of honeycomb polyimide resin comprises the following steps: B1. Add 2-vinyl-4,6-diamino-1,3,5-triazine, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, triethylamine and dimethyl sulfoxide into a reaction kettle, raise the temperature of the reaction kettle to 60-80° C., and keep the temperature for 2-4 hours to obtain a polyamide solution; B2. After the polyamide solution is poured into the honeycomb mold, the mold is placed in a freeze dryer, the temperature of the freeze dryer is lowered to -40~-60°C, and after being kept warm for 20~40 minutes, the temperature is raised to 0~10°C, and vacuum dried until the mold has a constant weight, to obtain a polyamide resin; B3. Add the mold into a tubular furnace, introduce nitrogen protection, heat the tubular furnace to 270±5°C at a heating rate of 5°C / min, and keep the temperature for 2-4 hours to obtain a polyimide resin; B4, after the polyamide-imide gel is peeled off from the mold, it is placed on a hot press at a temperature of 300-350° C., and high-temperature compression is performed for 20-30 minutes, and a honeycomb polyimide resin precursor is obtained by post-processing; B5. Add the oxidizing solution into the oil bath. After the temperature of the oil bath rises to 50-60°C, completely immerse the honeycomb polyimide resin precursor in the oxidizing solution. After soaking for 30-40 minutes, post-process and obtain the honeycomb polyimide resin.

5. The heat-insulating and high-temperature-resistant metal core fireproof board according to claim 2, characterized in that: In step B1, the amount ratio of 2-vinyl-4,6-diamino-1,3,5-triazine, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, triethylamine and dimethyl sulfoxide is 2-4 g:3-5 g:0.1-0.2 g:20-30 mL; in step B4, the pressure is 4-6 GPa, and the post-treatment includes: placing the polyimide aerogel in a stretching machine, controlling the longitudinal stretching ratio to 4-6:1, the transverse stretching ratio to 4-6:1, maintaining the tension, raising the temperature of the stretching machine to 300-400 ° C, and heat preservation treatment 0.5~1h, to obtain a honeycomb polyimide resin precursor; in step B5, the oxidizing liquid is obtained by mixing acetic acid, hydrogen peroxide and N,N-dimethylformamide, wherein the amount ratio of acetic acid, hydrogen peroxide and N,N-dimethylformamide is 1~2g:1~2g:20~30mL, and the post-treatment comprises: using a sampler to take the polyimide honeycomb layer precursor out of the oil bath, washing it with ethanol for 3~5 times, and then spreading the polyimide honeycomb layer precursor in a drying oven at a temperature of 60~80°C and vacuum drying it until the material has a constant weight, to obtain a honeycomb polyimide resin.

6. The heat-insulating and high-temperature-resistant metal core fireproof board according to claim 1, characterized in that: The preparation method of the modified silica aerogel precursor comprises the following steps: C1. Add bis(triethoxysilyl)methane and anhydrous ethanol into a reactor and stir at a stirring rate of 240-360 rpm. After stirring for 5-10 min, add saturated acetic acid aqueous solution into the reactor. While stirring, raise the temperature of the reactor to 60-80° C. and keep the temperature for 2-4 h to obtain a silica sol solution. C2, adding the silica sol solution into the reactor and stirring, the stirring rate is set to 60-80 rpm, and saturated ammonia water is added dropwise during the stirring process to adjust the pH value of the system to 8-9. After the adjustment is completed, stirring is continued for 5-10 minutes, and the silica gel is obtained by post-treatment; C3. Soak the silica gel in an ethanol solution, let it stand for 6 hours, then place it in a drying oven at 80°C and dry it for 20 to 30 minutes. Repeat the soaking and drying operation 3 to 5 times to obtain a modified silica aerogel precursor.

7. The heat-insulating and high-temperature-resistant metal core fireproof board according to claim 4, characterized in that: In step C1, the dosage ratio of bis(triethoxysilyl)methane, anhydrous ethanol and saturated acetic acid aqueous solution is 2-4 g: 2-3 g: 3-5 g; in step C2, the post-treatment operation includes: after the stirring is completed, the solution is placed in a drying oven at a temperature of 60° C. and vacuum dried until the system has a constant weight, and then the vacuum drying is continued for 2-3 hours to obtain a silica gel.

8. A method for preparing a heat-insulating and high-temperature-resistant metal core fireproof board according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, taking a metal plate cut by a CNC machine tool and having the same size as the composite structure layer, spin-coating a layer of epoxy resin on the upper and lower surfaces of the metal plate, and curing it at high temperature to obtain a metal plate core layer (300); S2. Spin-coat a 0.8-1.6 wt% zinc chloride solution on the metal plate core layer (300), take two composite framework layers, and respectively attach their support layers (200) to the upper and lower surfaces of the metal plate to obtain a fireproof plate precursor, put the fireproof plate precursor into a punching machine, and punch at a pressure of 200 MPa for 1-2 hours to obtain a fireproof plate.

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