High-efficiency flame-retardant artificial board, flame retardant and preparation method thereof

Abstract

The present invention discloses a highly efficient flame-retardant artificial board, a flame retardant thereof, and a preparation method. The flame retardant for the artificial board comprises a polyphosphate compound, ammonium borate, boric acid, and delignified biomass cellulose in a mass ratio of 5:(3-5):(2-5):(2-4). The flame retardant of the present invention utilizes the synergistic effect of the polyphosphate compound, ammonium borate, and boric acid to significantly enhance the carbonization ability of the artificial board under high temperature conditions, forming a dense carbon layer, thereby effectively preventing the transfer of heat and oxygen and significantly improving the flame retardant effect. The prepared green and highly efficient flame-retardant artificial board has an oxygen index of over 37%, does not release toxic or harmful gases during combustion, and has excellent environmental performance. By using cellulose as a carrier for the flame retardant and combining it with the antioxidant properties of boric acid, the present invention not only enhances the mechanical properties of the artificial board, but also improves its thermal stability, achieving a good balance between flame retardancy and mechanical properties.

Description

Technical Field

[0001] The present invention relates to a wood-based panel, in particular to a high-efficiency flame-retardant wood-based panel, a flame retardant thereof and a preparation method thereof. Background Art

[0002] Wood-based panels are made from wood or other non-wood plant materials. After mechanical processing, they are separated into various component materials and then bonded together with or without adhesives and other additives to form a sheet or molded product. They primarily include three product categories: plywood, particleboard, and fiberboard. Hundreds of derivative and further processed products exist, and they are widely used in industries such as construction, interior decoration, furniture manufacturing, and packaging. However, the raw materials used in wood-based panels are mostly plant fibers, which are flammable and therefore highly susceptible to fire. Reports indicate that over 21% of fires are caused by fiber materials such as wood, and 70% of residential fires are caused by the flammability of wood. Therefore, improving the flame retardancy of wood-based panels is one measure to reduce the incidence of fires.

[0003] The flame retardancy of existing artificial boards is often achieved by adding flame retardant ingredients to adhesives, mixing and stirring, and then evenly applying the adhesive between the board layers. While this method is simple and reduces the production cost of artificial boards, it has the following problems:

[0004] 1) It is very easy for the flame retardant component and the adhesive to be incompatible, which will affect the uniformity of the flame retardant application, resulting in a decrease in the overall flame retardant effect of the wood-based panel and a decrease in the mechanical properties;

[0005] 2) During the processing of the artificial board, the adhesive is applied between the boards. This means that the interior of the artificial board has flame retardant properties, but the board surface does not have flame retardant components. This will result in poor flame retardant effect on the board surface, affecting the overall fireproof and flame retardant function of the artificial board.

[0006] 3) Although existing wood-based panels utilize improved adhesives or improved environmentally friendly surface coatings, the finished panels still retain an odor from the glue and coating, which can affect the comfort of those who come into contact with them. If the odor cannot be removed over time, breathing it can affect people's health. Therefore, developing green, environmentally friendly, and highly flame-retardant wood-based panels while maintaining the required mechanical properties has become a key research priority. Summary of the Invention

[0007] In response to the problems of the above-mentioned existing artificial boards with poor flame retardant effect, mechanical properties and environmental pollution, the present invention provides a high-efficiency flame-retardant artificial board, its flame retardant and preparation method. The flame-retardant artificial board has excellent flame retardant properties, good mechanical properties and low harmful substance release, and meets green environmental protection requirements, and can be widely used in the fields of construction and home furnishing.

[0008] In order to achieve the above-mentioned object, the present invention provides a flame retardant for artificial boards, which comprises a polyphosphate compound, ammonium borate, boric acid and delignified biomass cellulose in a mass ratio of 5: (3-5): (2-5): (2-4).

[0009] When ammonium borate decomposes at high temperatures, it produces boron oxides and releases ammonia. These decomposition products help suppress flame spread at high temperatures and provide long-lasting flame retardant protection by forming a stable charred layer. The decomposition products of ammonium borate have the dual effects of suppressing flames and promoting carbonization. Through its ammonia-releasing properties, ammonium borate helps lower temperatures and suppress the formation of combustible gases, enhancing the flame retardant effect. During pyrolysis, ammonium borate and polyphosphate compounds form stable inorganic compounds such as phosphoborates. These compounds are highly stable at high temperatures and further promote carbonization, enhancing the flame retardant effect. Ammonium borate reacts not only with polyphosphate compounds but also with functional groups such as hydroxyl groups in delignified biomass cellulose, producing a more stable structure and enhancing flame retardancy.

[0010] The combination of polyphosphate compounds, ammonium borate and boric acid has the following advantages:

[0011] 1) Synergistically enhance flame retardant properties

[0012] Polyphosphate compounds, such as ammonium polyphosphate, form a stable phosphate film during pyrolysis, preventing flame spread and reducing heat conduction. When combined with boric acid and ammonium borate, the formation of boron oxide further enhances the stability of the carbonized layer, preventing the spread of flame and heat, and forming a more robust flame-retardant protective layer.

[0013] The inorganic substances (such as boron oxide) produced by the decomposition of ammonium borate and boric acid strengthen the protective effect of the phosphate film and improve the flame retardant effect, especially at high temperatures, where the flame retardant performance is more significant.

[0014] 2) Improve thermal stability

[0015] Boric acid and ammonium borate decompose at high temperatures to form boron oxide, which effectively improves the material's heat resistance, forming a high-temperature resistant protective film. Combined with polyphosphate compounds, this film's thermal stability is further enhanced, improving the material's performance in high-temperature environments.

[0016] This effect makes the composite system more advantageous than a single flame retardant system under high temperature conditions, avoiding the performance degradation caused by the instability of pyrolysis products.

[0017] 3) More stable flame retardant film layer

[0018] When polyphosphate, boric acid, and ammonium borate work together, the resulting film is stronger. Boric acid and ammonium borate promote the carbonization of the polyphosphate, creating a more stable carbonized layer that reduces flame spread and gas release, enhancing flame retardancy.

[0019] This film layer not only enhances the flame retardancy of the material, but also has a good reinforcement effect on the mechanical properties and durability of the material.

[0020] 4) Improved pyrolysis behavior and reduced harmful gas release

[0021] Under high temperature conditions, the decomposition of polyphosphate compounds releases phosphate ions, while boric acid produces boron oxides. These products work together to form a denser protective layer and reduce the release of harmful gases (such as CO and CO2).

[0022] In addition, the decomposition products of boric acid and ammonium borate can effectively capture or neutralize toxic gases, significantly reducing the emission of harmful substances during fires and improving the environmental friendliness and safety of the materials.

[0023] 5) Enhance the mechanical properties of materials

[0024] The addition of boric acid and ammonium borate may cross-link with polyphosphate through a chemical reaction, enhancing the mechanical strength and stability of the material. This chemical cross-linking not only improves the material's heat resistance, but also enhances its compressive strength, tensile strength and other mechanical properties.

[0025] Compared with a single flame retardant system, the three-in-one composite system can improve the comprehensive mechanical properties of the material while maintaining a good flame retardant effect, especially in high temperature environments.

[0026] Delignified biocellulose (such as poplar wood fiber) is primarily composed of cellulose, lignin, and a small amount of hemicellulose. Besides acting as a carrier, it also interacts with other biomass fibers in the wood-based panel raw materials (such as wood and bamboo fibers), particularly during the pyrolysis and flame retardant processes. The hydroxyl groups and other functional groups in these fibers react with the flame retardant, enhancing the flame retardant effect. Hydrogen bonding or other physical crosslinking enhances the overall stability and fire resistance of the material. Delignified biocellulose not only acts as a carrier but also interacts with other fibers and flame retardants to improve the material's performance.

[0027] Preferably, the polyphosphate compound is selected from one or more of ammonium polyphosphate, ammonium tripolyphosphate, and ammonium pyrophosphate, and the biomass fiber is selected from one or more of bamboo fiber, wood fiber, or straw fiber.

[0028] The second aspect of the present invention provides a method for preparing the flame retardant, which comprises the following steps: dissolving a polyphosphate compound, ammonium borate and boric acid in a cellulose solution, and then dispersing the cellulose solution to obtain a uniform flame retardant mixed solution.

[0029] Specifically, the dispersion treatment is performed by ultrasonic treatment at 20-40 kHz at 30-40° C. for 10-30 minutes.

[0030] In the above technical solution, polyphosphate compounds, ammonium borate and boric acid are compounded with cellulose through a solution method combined with ultrasonic dispersion technology, which significantly improves the uniform dispersion of the flame retardant material and effectively avoids the problem of flame retardant agglomeration. The prepared artificial board has excellent flame retardant properties.

[0031] Preferably, the mass fraction of the cellulose solution is 2-4%.

[0032] The third aspect of the present invention provides a method for preparing a high-efficiency flame-retardant artificial board, which comprises the following steps: adding the above-mentioned flame retardant to the artificial board raw material by spraying, and stirring at the same time to ensure uniform distribution of the flame retardant; drying the mixed material, applying glue, and then hot pressing to obtain the said high-efficiency flame-retardant artificial board.

[0033] Preferably, the weight ratio of the flame retardant to the wood-based panel raw material is (1-15):100.

[0034] Specifically, the hot pressing temperature is 150-200° C., the pressure is 3-6 MPa, and the time is 20-30 minutes.

[0035] Preferably, the moisture content of the raw material is controlled below 8% before hot pressing.

[0036] A fourth aspect of the present invention provides a high-efficiency flame-retardant artificial board produced by the above-mentioned preparation method.

[0037] Through the above technical solution, the present invention achieves the following beneficial effects:

[0038] The flame retardant of the present invention utilizes the synergistic effect of polyphosphate compounds, ammonium borate, and boric acid to significantly enhance the carbonization ability of wood-based panels under high-temperature conditions, forming a dense carbon layer that effectively blocks the transfer of heat and oxygen, significantly improving the flame retardant effect. The resulting green, highly efficient, flame-retardant wood-based panels have an oxygen index exceeding 37%, meeting the GB / T 8624-2012 B1 flame retardancy standard. They also release no toxic or harmful gases during combustion, demonstrating excellent environmental performance.

[0039] 2. The present invention uses cellulose as a carrier of the flame retardant and combines it with the antioxidant properties of boric acid, which not only improves the mechanical properties of the artificial board, but also improves its thermal stability, achieving a good balance between flame retardancy and mechanical properties.

[0040] 3. In a preferred technical solution of the present invention, polyphosphate compounds, ammonium borate and boric acid are compounded with cellulose by a solution method combined with ultrasonic dispersion technology, which significantly improves the uniform dispersion of the flame retardant material and effectively avoids the problem of flame retardant agglomeration. The prepared artificial board has excellent flame retardant properties.

[0041] 4. The artificial board prepared by the present invention uses biomass fiber as the raw material source, which is both environmentally friendly and renewable, reduces production costs, conforms to the concept of sustainable development, and provides a new idea for the high value-added utilization of traditional artificial boards.

[0042] 5. The preparation process of the present invention is simple and easy, the raw materials are widely available, and it is suitable for industrial production. At the same time, it gives the artificial board high-efficiency flame retardant properties, broadening its application range in the fields of construction, home furnishing, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a TEM image of a cellulose solution of the present invention mixed with a polyphosphate compound, ammonium borate, and boric acid;

[0044] Figure 2 This is a thermogravimetric analysis (TGA) curve of the green and efficient flame-retardant artificial board obtained in Example 1 of the present invention;

[0045] Figure 3 This is the bending stress-strain curve of the green, high-efficiency, flame-retardant artificial board obtained in Example 1 of the present invention. DETAILED DESCRIPTION

[0046] The following is a detailed description of the specific embodiments of the present invention in conjunction with the examples. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0047] Example 1

[0048] The preparation method of high-efficiency flame-retardant artificial board is as follows:

[0049] 1) Bamboo fibers (length controlled within the range of 2-5 cm) were soaked in ammonia water for 12 hours, then delignified with 2M sodium hydroxide and 1M sodium sulfite. After washing to neutrality, they were bleached with 3% hydrogen peroxide to obtain cellulose raw material.

[0050] 2) Disperse 4 g of cellulose in 196 mL of deionized water and ultrasonicate the solution (25 kHz, 30°C) for 30 minutes to obtain a cellulose solution.

[0051] 3) 10g of ammonium polyphosphate, 6g of ammonium borate and 4g of boric acid were added to the cellulose solution prepared in step 2) and treated with an ultrasonic oscillator (frequency 30kHz, temperature 35°C) for 20 minutes until the flame retardant was evenly dispersed to obtain a flame retardant mixture. From the SEM image ( Figure 1 ) It can be seen that the flame retardant is evenly distributed and firmly bound to the cellulose surface.

[0052] 4) Spray 200g of the flame retardant mixture evenly on 1300g of medium-density fiberboard (MDF) raw material, stir evenly, and then air-dry at 60°C until the moisture content is less than 8%.

[0053] The above medium density fiberboard (MDF) raw materials include:

[0054] Sawdust: A mixture of bark and sawdust. The particle size of sawdust is about 0.2~1.5mm, accounting for about 80%-85% of the raw materials.

[0055] Binder: Urea-formaldehyde resin (UF) is used as a binder, with a content of 10% to 12% of the sawdust mass. Urea-formaldehyde resin can form a strong bond with the sawdust when heated, providing excellent structural stability.

[0056] Moisture content: Before spraying the flame retardant mixture, the moisture content of the wood chips and binder mixture is about 8%~10%.

[0057] 5) The mixed raw materials are sizing treated, and hot pressing equipment is used for 30 minutes at a pressure of 3 MPa and a temperature of 150°C to produce a green and efficient flame-retardant artificial board.

[0058] 6) Oxygen index test results show that the oxygen index of the wood-based panel is over 37%, and the flame retardant performance is excellent; the thermogravimetric analysis results are as follows Figure 2 As shown, it shows that the artificial board has excellent thermal stability; the bending stress-strain curve is as shown in Figure 3 As shown, it shows that artificial boards have excellent mechanical properties and are suitable for high-standard flame retardant materials in the fields of construction and home furnishing.

[0059] Example 2

[0060] The preparation method of high-efficiency flame-retardant artificial board is as follows:

[0061] 1) Rice straw fiber was soaked in ammonia water for 24 hours, then delignified with 5M sodium hydroxide and 2.5M sodium sulfite, washed to neutrality, and then bleached with 3% hydrogen peroxide to obtain purified cellulose raw material.

[0062] 2) Disperse 8 g of cellulose in 192 g of deionized water and treat with an ultrasonicator (frequency 20 kHz, temperature 40°C) for 20 minutes to obtain a cellulose solution.

[0063] 3) 10 g of ammonium tripolyphosphate, 10 g of ammonium borate, and 10 g of boric acid were added to the cellulose solution prepared in step 2) and treated with an ultrasonic oscillator (frequency 20 kHz, temperature 30°C) for 30 minutes until the flame retardant was uniformly dispersed to obtain a flame retardant mixture.

[0064] 4) Spray 150g of the flame retardant mixture evenly on 1300g of particleboard raw materials, stir evenly, and air-dry at 50°C until the moisture content is less than 8%.

[0065] The above particleboard raw materials include:

[0066] Sawdust and wood shavings: mainly use mixed sawdust of coniferous wood and hardwood, among which the particle size distribution of sawdust particles is between 1 and 3 mm, accounting for about 75% to 80% of the raw materials.

[0067] Binder: Phenolic resin (PF) is used as a binder, with the resin added at 10% to 15% of the wood chips. Phenolic resin provides good water resistance and strength at high temperatures and is a commonly used binder in particleboard manufacturing.

[0068] Moisture Content: After mixing sawdust, wood shavings, and a binder, the moisture content is approximately 6% to 8%. 5) The treated raw materials are sizing-treated and then hot-pressed at 6 MPa and 170°C for 25 minutes to produce a green, highly effective, flame-retardant wood-based panel.

[0069] 6) Oxygen index test results show that the oxygen index of the artificial board reaches 39%, with excellent thermal stability; the flame retardant properties and mechanical properties meet the high standards of flame retardant grade of building materials, making it suitable for interior decoration and high-safety application scenarios.

[0070] Example 3

[0071] The preparation method of high-efficiency flame-retardant artificial board is as follows:

[0072] 1) Poplar wood fiber was soaked in ammonia water for 24 hours, then delignified with 5M sodium hydroxide and 2.5M sodium sulfite, washed to neutrality, and then bleached with 3% hydrogen peroxide to obtain purified cellulose raw material.

[0073] 2) Disperse 6 g of cellulose in 194 mL of deionized water and ultrasonicate for 20 minutes (40 kHz, 40°C) to obtain a cellulose solution.

[0074] 3) 5 g of ammonium tripolyphosphate, 5 g of ammonium pyrophosphate, 8 g of ammonium borate, and 6 g of boric acid were added to the cellulose solution prepared in step 2) and treated with an ultrasonic oscillator (frequency 40 kHz, temperature 40°C) for 10 minutes until the flame retardant was uniformly dispersed to obtain a flame retardant mixture.

[0075] 4) Spray 130 mL of the flame retardant mixture evenly onto 1300 g of plywood, stir evenly, and air-dry at 50°C until the moisture content is less than 8%.

[0076] The above plywood raw materials include:

[0077] Wood veneer: veneer made of poplar or pine, with a thickness of 1.5~3mm, and the arrangement direction of each layer of veneer alternates.

[0078] Adhesive: Polyurethane (PU) adhesive is used as the adhesive, with a content of 8% to 10% of the wood veneer mass. PU adhesive has good water resistance and excellent bond strength, making it suitable for plywood production.

[0079] Moisture content: After spraying the flame retardant mixture, the moisture content of the plywood substrate is about 5%~7%.

[0080] 5) The treated raw materials are sizing treated, and then hot pressed at a pressure of 3 MPa and a temperature of 200° C. for 20 minutes to produce a green and highly efficient flame-retardant artificial board.

[0081] 6) Oxygen index test results show that the oxygen index of the artificial board reaches 37%, with excellent thermal stability; the flame retardant properties and mechanical properties meet the high standards of flame retardant grade of building materials, making it suitable for interior decoration and high-safety application scenarios.

[0082] Comparative Example 1

[0083] The medium density fiberboard in Example 1.

[0084] Comparative Example 2

[0085] Other conditions were the same as in Example 1, except that step 3 was omitted. The oxygen index of the wood-based panel was measured to be only 21%.

[0086] Comparative Example 3

[0087] Other conditions were the same as in Example 1, except that the flame retardant in step 3) was replaced with 20 g of ammonium polyphosphate. The oxygen index of the artificial board was measured to be only 25%.

[0088] Comparative Example 4

[0089] Other conditions were the same as in Example 1, except that the flame retardant in step 3) was replaced with 20 g of boric acid. The oxygen index of the artificial board was measured to be only 26%.

[0090] Comparative Example 5

[0091] Other conditions were the same as in Example 1, except that the flame retardant in step 3) was replaced with 20 g of ammonium borate. The oxygen index of the artificial board was measured to be only 29%.

[0092] Comparative Example 6

[0093] Other conditions were the same as in Example 1, except that non-delignified raw materials were used. The oxygen index of the wood-based panel was measured to be only 33%, and the thermal stability and mechanical properties were relatively poor.

[0094] Thermal Stability: Undelignified raw materials contain higher levels of lignin, which results in poor thermal stability during heating. Lignin decomposes earlier during pyrolysis and releases more volatile gases (such as phenols), which can spread flames more easily in the event of a fire. Therefore, undelignified raw materials exhibit lower thermal stability and flame retardancy than delignified raw materials.

[0095] Flame retardant properties: The presence of lignin affects the dispersibility and reactivity of flame retardants (such as polyphosphate compounds and boric acid), reducing the flame retardant effect. The decomposition of lignin increases the release of harmful gases, which affects the flame retardant properties of the board.

[0096] Mechanical Properties: In undelignified raw materials, lignin, as a natural organic polymer, provides a certain degree of rigidity and support. However, due to the uneven structure of lignin, the mechanical properties of the board are not as stable as those of delignified materials. Therefore, undelignified raw materials exhibit lower strength and toughness.

[0097] Comparative Example 7

[0098] Other conditions were the same as in Example 1, except that 10 g of ammonium polyphosphate and 10 g of ammonium borate were used in step 3) instead of boric acid. The oxygen index of the wood-based panel was measured to be only 33%, and both thermal stability and mechanical properties were poor.

[0099] Flame retardancy: Boric acid plays a crucial role in flame retardant systems, particularly at high temperatures, where it forms flame-retardant borates and helps generate a carbonized layer, inhibiting flame spread. Without boric acid, the flame retardant effect of the entire system is weakened. While both ammonium polyphosphate and ammonium borate exhibit some flame retardancy, the absence of boric acid may result in less-than-optimal carbonization, thus reducing the flame retardancy of the board.

[0100] Thermal stability: The lack of boric acid can affect the thermal stability of the board at high temperatures. Boric acid helps form a protective carbonized layer at high temperatures, slowing the pyrolysis process and thus improving thermal stability. Without boric acid, ammonium polyphosphate and ammonium borate are insufficient to effectively form this protective layer, resulting in poor thermal stability.

[0101] Mechanical properties: The lack of boric acid will also affect the mechanical properties, especially during the formation and pyrolysis of the flame retardant layer, the stability and strength of the carbonized layer are low, thus affecting the overall strength of the board.

[0102] Comparative Example 8

[0103] Other conditions were the same as in Example 1, except that 10 g of ammonium polyphosphate and 10 g of boric acid were used in step 3) instead of ammonium borate. The oxygen index of the artificial board was measured to be only 30%, and both thermal stability and mechanical properties were poor.

[0104] Flame retardancy: Ammonium borate is a common flame retardant. It decomposes to release ammonia, helping to reduce flame spread at high temperatures. It also reacts with other inorganic components (such as polyphosphates) to form a stable carbonized layer. Without ammonium borate, the flame retardant effect is reduced, especially in the early stages of a fire, where the lack of ammonia's inhibitory effect can cause the flame to spread more rapidly. While boric acid itself has some flame retardant properties, the synergistic effect between boric acid and ammonium polyphosphate is not as strong as the synergistic effect between ammonium borate and ammonium polyphosphate. The absence of ammonium borate further weakens the flame retardant effect.

[0105] Thermal stability: Ammonium borate decomposes to generate ammonia, which helps reduce the temperature and slows down the thermal decomposition rate, improving the thermal stability of the material. In the absence of ammonium borate, boric acid and ammonium polyphosphate can also play a certain role, but lack the temperature-regulating effect of ammonia release, resulting in relatively poor thermal stability.

[0106] Mechanical properties: Similarly, the absence of ammonium borate affects mechanical properties because it enhances the strength and stability of the carbonized layer. Without ammonium borate, the carbonized layer may form incomplete or unstable, thus affecting mechanical properties, especially strength retention at high temperatures.

[0107] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0108] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0109] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for preparing a high-efficiency flame-retardant artificial board, characterized in that: The method comprises the following steps: adding a flame retardant to the raw material of the artificial board by spraying, and stirring the mixture at the same time to ensure uniform distribution of the flame retardant; drying the mixed material, applying a glue treatment, and then hot-pressing to obtain the high-efficiency flame-retardant artificial board; wherein the flame retardant comprises a polyphosphate compound, ammonium borate, boric acid and delignified biomass cellulose in a mass ratio of 5: (3-5): (2-5): (2-4); the polyphosphate compound is selected from one or more of ammonium polyphosphate, ammonium tripolyphosphate and ammonium pyrophosphate, and the raw material of the biomass cellulose is one or more of bamboo fiber, wood fiber or straw fiber.

2. The preparation method according to claim 1, characterized in that The preparation method of the flame retardant comprises the following steps: dissolving a polyphosphate compound, ammonium borate and boric acid in a delignified biomass cellulose solution, and then dispersing the solution to obtain a uniform flame retardant mixed liquid.

3. The preparation method according to claim 2, characterized in that The dispersion treatment is performed by ultrasonic treatment at 20-40 kHz for 10-30 minutes at 30-40°C.

4. The preparation method according to claim 2, characterized in that The mass fraction of the delignified biomass cellulose solution is 2-4%.

5. The preparation method according to claim 1, characterized in that The weight ratio of the flame retardant to the raw material of the artificial board is (1-15):

100.

6. The preparation method according to claim 1, wherein The hot pressing temperature is 150-200° C., the pressure is 3-6 MPa, and the time is 20-30 minutes.

7. The preparation method according to claim 1, characterized in that The moisture content of the raw materials was controlled below 8% before hot pressing.

8. A high-efficiency flame-retardant artificial board prepared by the preparation method according to any one of claims 1 to 7.

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