Preparation method of biomass fiber high-filled thermal insulation and flame-retardant decorative wallboard

Abstract

The application belongs to the field of building materials, and particularly relates to a preparation method of a biomass fiber high-filling thermal insulation and flame-retardant decorative wallboard; and specifically comprises the following steps: uniformly applying an epoxy resin adhesive to the surface of a biomass fiber base plate material, and laying a decorative paper; uniformly applying the epoxy resin adhesive to the surface of the decorative paper, and laying a wear-resistant layer; placing the base plate material with the laid decorative paper and wear-resistant layer into a flat vulcanizing machine, and obtaining the biomass fiber high-filling thermal insulation and flame-retardant decorative wallboard after hot pressing and curing; not only is firm adhesion between materials achieved, and the overall stability and durability of the wallboard are improved, but also the thermal insulation and flame-retardant performance is enhanced through a multi-layer structure, and use safety is ensured.

Description

Technical Field

[0001] This invention belongs to the field of building materials, specifically relating to a method for preparing a biomass fiber-filled thermal insulation and flame-retardant decorative wall panel. Background Technology

[0002] As people's demands for aesthetics, safety, and environmental friendliness in their living environments increase, traditional wood-based decorative panels have secured a place in the market due to their natural textures and excellent decorative effects. However, their inherent flammability and poor moisture resistance have become key factors restricting their widespread application. Especially in modern home environments, the importance of fire safety and indoor air quality is becoming increasingly prominent, prompting the industry to continuously explore new, high-performance decorative materials.

[0003] Traditional wood decorative panels also have two prominent drawbacks: First, they are flammable, and inadequate fire prevention measures can easily cause fires. For families that frequently use open flames, wood panel wall decorations pose a significant safety hazard. Second, they are not moisture-resistant and are prone to mold growth in high humidity environments, which not only affects aesthetics but also indoor air quality and poses a health hazard. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention aims to provide a method for preparing a biomass fiber-filled, heat-insulating, flame-retardant decorative wall panel. The base material of this invention, developed primarily from biomass fiber, possesses advantages such as excellent heat insulation performance, zero formaldehyde content, fire and moisture resistance, and good dimensional stability. After coating or covering with a surface decorative layer, various building heat-insulating and decorative wall panels can be formed. This method efficiently utilizes agricultural waste such as straw and other plant stem fibers to prepare low-carbon new material base materials, replacing raw natural wood and thus significantly reducing the consumption of forest resources in the decoration industry chain.

[0005] To achieve the above objectives, the present invention employs the following technical solution:

[0006] This invention provides a method for preparing a biomass fiber-filled, heat-insulating, flame-retardant decorative wall panel, specifically including the following steps:

[0007] Epoxy resin adhesive is evenly applied to the surface of the biomass fiber-based board, and then a decorative paper is laid on it; epoxy resin adhesive is evenly applied to the surface of the decorative paper, and then a wear-resistant layer is laid on it; the base board with the decorative paper and wear-resistant layer is placed in a flat vulcanizing machine, hot-pressed, and then left to cure statically to obtain the biomass fiber high-filling heat-insulating and flame-retardant decorative wall panel.

[0008] Preferably, the preparation method of the epoxy resin adhesive specifically includes the following steps:

[0009] Epoxy resin is dissolved in benzyl alcohol, diethylenetriamine is added and stirred thoroughly to obtain an epoxy resin adhesive; the mass ratio of epoxy resin, benzyl alcohol and diethylenetriamine is 10:1:1.

[0010] Preferably, the preparation method of the biomass fiber-based board includes the following steps:

[0011] Modified biomass fiber, modified inorganic powder, and modified expandable polystyrene are stirred and mixed evenly. The mixture is then placed into a mold, and the mold is placed in a flat vulcanizing machine. After hot pressing, the biomass fiber-based board is obtained.

[0012] Preferably, the mass ratio of the modified biomass fiber, modified inorganic powder and modified expandable polystyrene is (5-6):2:1.

[0013] Preferably, the preparation method of the modified biomass fiber specifically includes the following steps:

[0014] The synthetic organic resin is dissolved in anhydrous ethanol to form a 20%–30% solution. The synthetic organic resin solution is then uniformly sprayed onto the surface of the pretreated biomass fiber and dried to obtain the modified biomass fiber.

[0015] Preferably, the method for preparing the pretreated biomass fiber includes the following steps:

[0016] The crop straw is washed and dried, then crushed into fiber powder smaller than 5mm using a pulverizer. The fiber powder is then soaked in an alkaline aqueous solution for 2-3 days and heated at 100-120℃ for 12-24 hours to obtain pretreated biomass fiber.

[0017] Preferably, the preparation method of the modified inorganic powder specifically includes the following steps:

[0018] Magnesium hydroxide and calcium chloride are mixed evenly, and the synthetic organic resin is dissolved in anhydrous ethanol to form a 25% to 35% solution. Under stirring, the synthetic organic resin solution is evenly sprayed onto the surface of the inorganic powder and dried thoroughly at 60 to 80°C to obtain the modified inorganic powder.

[0019] Preferably, the method for preparing the synthetic organic resin includes the following steps:

[0020] Polycaprolactone diol and dibutyltin dilaurate were stirred evenly under nitrogen protection and heated to 40-80°C. Maleic anhydride was then added, and the reaction was continued to be stirred for 1-3 hours under nitrogen protection. The reaction temperature was then lowered to 10-30°C, and aminopropyltriethoxysilane was added. The reaction was continued to be stirred for 1-3 hours to obtain a synthetic organic resin containing siloxane end groups.

[0021] Preferably, the mass ratio of polycaprolactone diol, maleic anhydride, dibutyltin dilaurate and aminopropyltriethoxysilane is 100:20:(2-3):(10-12).

[0022] Preferably, the preparation method of the modified expandable polystyrene specifically includes the following steps:

[0023] A silane coupling agent is dissolved in anhydrous ethanol to form a 20-30% solution. The silane coupling agent solution is then uniformly sprayed onto the surface of expandable polystyrene and dried to obtain modified expandable polystyrene.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] This invention utilizes epoxy resin adhesive to bond biomass fiber-based boards, decorative paper, and a wear-resistant layer to create a thermally insulated and flame-retardant decorative wall panel. This not only achieves strong adhesion between materials, enhancing the overall stability and durability of the wall panel, but also strengthens its thermal insulation and flame-retardant properties through a multi-layered structure, ensuring safe use. Simultaneously, the aesthetically pleasing decorative paper and wear-resistant layer provide the wall panel with excellent decorative effects and wear resistance. Furthermore, the main raw material of this invention, crop straw, is widely available and inexpensive, significantly reducing the consumption of forest resources in the decoration industry chain and promoting resource recycling in the building decoration industry. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0027] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0028] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0029] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0030] This invention achieves flame retardancy in the base material by adding a certain proportion of inorganic powders such as calcium chloride and magnesium hydroxide to biomass fibers. Simultaneously, to enhance the adhesion between the organic biomass fibers and inorganic mineral components and improve the moisture resistance of the base material, this invention uses a directionally synthesized organic resin to perform organic-inorganic hybrid modification. During the compounding process of biomass fibers, organic synthetic resin, and inorganic mineral powder, the moisture content and other undesirable components of the biomass fibers significantly affect the organic-inorganic hybrid modification. Excessive moisture content can lead to defects such as voids or internal stress within the base material, while completely dry biomass fibers are relatively brittle, and the shear stress during molding can cut the fibers. Furthermore, biomass fibers may contain undesirable components, such as lignin, that affect their surface grafting modification. Therefore, pretreatment of the biomass fibers is necessary to remove excess moisture and other undesirable components.

[0031] There are three common treatment methods for biomass fibers: acid soaking, alkali soaking, and heat treatment. This invention optimizes the pretreatment process through experiments: first, the biomass fibers are soaked in alkali, and the pH range and soaking time are controlled to remove lignin to the maximum extent while ensuring that the cellulose and hemicellulose in the raw materials are not damaged; after cleaning the raw materials after alkali soaking, the moisture and other volatile substances in the biomass fibers are controlled at a reasonable temperature and time, thereby improving the mechanical properties and surface characteristics of the biomass fiber raw materials.

[0032] This invention provides a method for preparing a biomass fiber-filled, heat-insulating, flame-retardant decorative wall panel, characterized by the following steps:

[0033] Biomass fiber pretreatment: Agricultural crop straw, such as rice straw, wheat straw, or corn straw (or reed stalks, branches, sawdust, low-quality wood, etc.), is washed and dried, then crushed into fiber powder less than 5mm using a pulverizer. The fiber powder is then soaked in an alkaline aqueous solution for 2-3 days, and then heated at 100-120℃ for 12-24 hours to obtain pretreated biomass fiber. The preferred pH value of the alkaline aqueous solution is 11.

[0034] Organic resin synthesis: Weigh out 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 2-3 parts of dibutyltin dilaurate, and 10-12 parts of aminopropyltriethoxysilane according to their respective mass percentages. Add polycaprolactone diol and dibutyltin dilaurate sequentially to a three-necked flask, stir thoroughly under nitrogen protection, and heat to 40-80°C. While continuously stirring, slowly add maleic anhydride to the flask, and continue stirring for 1-3 hours under nitrogen protection and at 40-80°C. Lower the reaction temperature to 10-30°C, and slowly add aminopropyltriethoxysilane dropwise under rapid stirring, continuing the reaction for 1-3 hours to obtain the synthetic organic resin containing siloxane end groups. Maleic anhydride can be replaced with succinic anhydride or glutaric anhydride, or other dicarboxylic acid anhydrides.

[0035] Biomass fiber modification: Weigh 100 parts of the pretreated biomass fiber and 12-15 parts of synthetic organic resin according to the mass percentage; dissolve the synthetic organic resin in anhydrous ethanol to form a 20%-30% solution. Under stirring, uniformly spray the synthetic organic resin solution onto the surface of the biomass fiber and dry it thoroughly at 60-80℃ to obtain the modified biomass fiber.

[0036] Surface modification of inorganic mineral powder: Weigh out 100 parts by mass of magnesium hydroxide, 100 parts by mass of calcium chloride, and 25-30 parts by mass of synthetic organic resin. Mix the magnesium hydroxide and calcium chloride evenly, and dissolve the synthetic organic resin in anhydrous ethanol to form a 25%-35% solution. Under stirring, spray the synthetic organic resin solution evenly onto the surface of the inorganic powder and dry it thoroughly at 60-80℃ to obtain the modified inorganic powder.

[0037] Modification of expandable polystyrene:

[0038] Weigh out 100 parts of expandable polystyrene and 2-3 parts of silane coupling agent according to the mass percentage. Dissolve the silane coupling agent in anhydrous ethanol to form a 20%-30% solution. Under stirring, spray the silane coupling agent solution evenly onto the surface of the expandable polystyrene and dry it thoroughly at 60-80℃ to obtain modified expandable polystyrene.

[0039] Low-density biomass fiber-based boards are hot-pressed into shape:

[0040] The modified biomass fiber, modified inorganic powder, and modified expandable polystyrene are mixed evenly according to a mass ratio of (5-6):2:1. The mixture is then placed into a mold, which is placed in a flat vulcanizing machine and hot-pressed at 110-120℃ and 15-20MPa for 60-70 minutes to obtain the low-density biomass fiber-based board. The biomass fiber-based board prepared by this invention, through the beneficial compounding of biomass fiber, inorganic powder, synthetic resin, and expandable polystyrene, exhibits excellent thermal insulation, fire resistance, moisture resistance, and dimensional stability.

[0041] Surface coating of low-density biomass fiber-based boards:

[0042] Epoxy resin, benzyl alcohol, and diethylenetriamine were weighed out in a mass ratio of 10:1:1. The epoxy resin was dissolved in benzyl alcohol, and the diethylenetriamine was added and stirred thoroughly to obtain an epoxy resin adhesive. The epoxy resin adhesive was evenly applied to the surface of a low-density biomass fiber-based board, and a facing paper was laid on top. Then, the epoxy resin adhesive was evenly applied to the surface of the facing paper, and a wear-resistant layer was laid on top. The biomass fiber-based board with the facing paper and wear-resistant layer was placed in a flat vulcanizing machine and hot-pressed at 60–80°C and 5–8 MPa for 10–30 minutes. After removal, it was allowed to stand for curing for 2–3 days to obtain the biomass fiber high-filling thermal insulation and flame-retardant decorative wall panel. Preferably, colored facing paper and a PET wear-resistant layer are used. The epoxy resin adhesive can also be replaced with a light-cured resin.

[0043] The present invention has the following advantages:

[0044] (1) Pretreatment of biomass fiber: Biomass fiber is pretreated by first soaking in alkali and then heating. This method does not require expensive equipment and complex modification processes, and effectively removes excess moisture, lignin and flammable components from biomass fiber.

[0045] (2) Synthesis of organic resin containing siloxane end groups: The organic resin synthesized by the present invention has a simple synthesis process and low cost. The organic resin adhesive itself has low viscosity, but its siloxane end groups have strong adhesion to biomass fibers and inorganic powders.

[0046] (3) Surface modification of biomass fiber and inorganic powder: By adding an appropriate amount of synthetic organic resin, it is ensured that the materials have strong adhesion and that the base plate has excellent flame retardant properties.

[0047] (4) Hot pressing of biomass fiber-based board: The base board of the present invention is hot pressing. Through a large number of experiments, a more reasonable temperature and pressure were determined to ensure that expandable polystyrene foams without melting, and to ensure that the base board has a low density. The biomass fiber and inorganic powder in the base board are compacted due to the volume expansion of expandable polystyrene.

[0048] (5) Surface coating of biomass fiber-based boards. The present invention uses an appropriate ratio of epoxy resin adhesive and a thermosetting temperature to ensure that the decorative paper and wear-resistant layer are firmly bonded to the surface of the biomass-based board.

[0049] Example 1

[0050] Rice straw is washed and dried, then crushed into fiber powder smaller than 5mm using a pulverizer. The fiber powder is then soaked in an alkaline aqueous solution with a pH of 11 for 2 days, and then heated at 100℃ for 24 hours to obtain pretreated biomass fiber.

[0051] Organic resin synthesis: According to the mass percentage, weigh 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 2 parts of dibutyltin dilaurate, and 10 parts of aminopropyltriethoxysilane. Add polycaprolactone diol and dibutyltin dilaurate sequentially to a three-necked flask, stir evenly under nitrogen protection, and heat to 40°C. While stirring continuously, slowly add maleic anhydride to the three-necked flask, and continue stirring for 3 hours under nitrogen protection and 40°C. Lower the reaction temperature to 10°C, and slowly add aminopropyltriethoxysilane dropwise under rapid stirring, and continue stirring for 3 hours to obtain the synthetic organic resin containing siloxane end groups.

[0052] Biomass fiber modification: Weigh 100 parts of the pretreated biomass fiber and 12 parts of synthetic organic resin according to the mass percentage; dissolve the synthetic organic resin in anhydrous ethanol to form a 20% solution. Under stirring, uniformly spray the synthetic organic resin solution onto the surface of the biomass fiber and dry it thoroughly at 60°C to obtain the modified biomass fiber.

[0053] Surface modification of inorganic mineral powder: Weigh out 100 parts by mass of magnesium hydroxide, 100 parts by mass of calcium chloride, and 25 parts by mass of synthetic organic resin. Mix magnesium hydroxide and calcium chloride evenly, and dissolve the synthetic organic resin in anhydrous ethanol to form a 25% solution. Under stirring, spray the synthetic organic resin solution evenly onto the surface of the inorganic powder and dry it thoroughly at 60°C to obtain the modified inorganic powder.

[0054] Modification of expandable polystyrene:

[0055] Weigh out 100 parts of expandable polystyrene and 2 parts of silane coupling agent according to the mass percentage. Dissolve the silane coupling agent in anhydrous ethanol to form a 20% solution. Under stirring, spray the silane coupling agent solution evenly onto the surface of the expandable polystyrene and dry it thoroughly at 60°C to obtain modified expandable polystyrene.

[0056] Low-density biomass fiber-based boards are hot-pressed into shape:

[0057] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene were mixed evenly in a mass ratio of 5:2:1. The mixture was then placed into a mold and placed in a flat vulcanizing machine. The mold was hot-pressed at 110°C and 20MPa for 60 minutes to obtain the low-density biomass fiber-based board.

[0058] Surface coating of low-density biomass fiber-based boards:

[0059] Epoxy resin, benzyl alcohol, and diethylenetriamine were weighed out in a mass ratio of 10:1:1. The epoxy resin was dissolved in benzyl alcohol, and the diethylenetriamine was added and stirred thoroughly to obtain an epoxy resin adhesive. The epoxy resin adhesive was evenly applied to the surface of a low-density biomass fiber-based board, and a facing paper was laid on top. Then, the epoxy resin adhesive was evenly applied to the surface of the facing paper, and a wear-resistant layer was laid on top. The biomass fiber-based board with the facing paper and wear-resistant layer was placed in a flat vulcanizing machine and hot-pressed at 60℃ and 8MPa for 10 minutes. After removal, it was allowed to stand for 2 days to cure, resulting in the biomass fiber-filled, heat-insulating, flame-retardant decorative wall panel.

[0060] Example 2

[0061] The corn stalks are washed and dried, then crushed into fiber powder smaller than 5 mm using a pulverizer. The fiber powder is then soaked in an alkaline aqueous solution with a pH of 11 for 2 days, and then heated at 110℃ for 16 hours to obtain pretreated biomass fiber.

[0062] Organic resin synthesis: According to the mass percentage, weigh 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 3 parts of dibutyltin dilaurate, and 11 parts of aminopropyltriethoxysilane. Add polycaprolactone diol and dibutyltin dilaurate sequentially to a three-necked flask, stir evenly under nitrogen protection, and heat to 50°C. While stirring continuously, slowly add maleic anhydride to the three-necked flask, and continue stirring for 2 hours under nitrogen protection and 50°C. Lower the reaction temperature to 20°C, and slowly add aminopropyltriethoxysilane dropwise under rapid stirring, and continue stirring for 2 hours to obtain the synthetic organic resin containing siloxane end groups.

[0063] Biomass fiber modification: Weigh 100 parts of the pretreated biomass fiber and 14 parts of synthetic organic resin according to the mass percentage; dissolve the synthetic organic resin in anhydrous ethanol to form a 25% solution. Under stirring, uniformly spray the synthetic organic resin solution onto the surface of the biomass fiber and dry it thoroughly at 70°C to obtain the modified biomass fiber.

[0064] Surface modification of inorganic mineral powder: Weigh out 100 parts by mass of magnesium hydroxide, 100 parts by mass of calcium chloride, and 27 parts by mass of synthetic organic resin. Mix magnesium hydroxide and calcium chloride evenly, and dissolve the synthetic organic resin in anhydrous ethanol to form a 30% solution. Under stirring, spray the synthetic organic resin solution evenly onto the surface of the inorganic powder and dry it thoroughly at 70°C to obtain the modified inorganic powder.

[0065] Modification of expandable polystyrene:

[0066] Weigh out 100 parts of expandable polystyrene and 3 parts of silane coupling agent according to the mass percentage. Dissolve the silane coupling agent in anhydrous ethanol to form a 25% solution. Under stirring, spray the silane coupling agent solution evenly onto the surface of the expandable polystyrene and dry it thoroughly at 70°C to obtain modified expandable polystyrene.

[0067] Low-density biomass fiber-based boards are hot-pressed into shape:

[0068] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene were mixed evenly in a mass ratio of 5.5:2:1. The mixture was then placed into a mold and placed in a flat vulcanizing machine. The mold was hot-pressed at 115°C and 18MPa for 65 minutes to obtain the low-density biomass fiber-based board.

[0069] Surface coating of low-density biomass fiber-based boards:

[0070] Epoxy resin, benzyl alcohol, and diethylenetriamine were weighed out in a mass ratio of 10:1:1. The epoxy resin was dissolved in benzyl alcohol, and the diethylenetriamine was added and stirred thoroughly to obtain an epoxy resin adhesive. The epoxy resin adhesive was evenly applied to the surface of a low-density biomass fiber-based board, and a facing paper was laid on top. Then, the epoxy resin adhesive was evenly applied to the surface of the facing paper, and a wear-resistant layer was laid on top. The biomass fiber-based board with the facing paper and wear-resistant layer was placed in a flat vulcanizing machine and hot-pressed at 70℃ and 7MPa for 20 minutes. After removal, it was allowed to stand for 3 days to cure, resulting in the biomass fiber-filled, heat-insulating, flame-retardant decorative wall panel.

[0071] Example 3

[0072] Wheat straw is washed and dried, then crushed into fiber powder smaller than 5mm using a pulverizer. The fiber powder is then soaked in an alkaline aqueous solution with a pH of 11 for 3 days, and then heated at 120℃ for 12 hours to obtain pretreated biomass fiber.

[0073] Organic resin synthesis: According to the mass percentage, weigh 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 3 parts of dibutyltin dilaurate, and 12 parts of aminopropyltriethoxysilane. Add polycaprolactone diol and dibutyltin dilaurate sequentially to a three-necked flask, stir evenly under nitrogen protection, and heat to 80°C. While stirring continuously, slowly add maleic anhydride to the three-necked flask, and continue stirring for 1 hour under nitrogen protection and 80°C. Lower the reaction temperature to 30°C, and slowly add aminopropyltriethoxysilane dropwise under rapid stirring, and continue stirring for 1 hour to obtain the synthetic organic resin containing siloxane end groups.

[0074] Biomass fiber modification: Weigh 100 parts of the pretreated biomass fiber and 15 parts of synthetic organic resin according to the mass percentage; dissolve the synthetic organic resin in anhydrous ethanol to form a 30% solution. Under stirring, uniformly spray the synthetic organic resin solution onto the surface of the biomass fiber and dry it thoroughly at 80°C to obtain the modified biomass fiber.

[0075] Surface modification of inorganic mineral powder: Weigh out 100 parts by mass of magnesium hydroxide, 100 parts by mass of calcium chloride, and 30 parts by mass of synthetic organic resin. Mix magnesium hydroxide and calcium chloride evenly, and dissolve the synthetic organic resin in anhydrous ethanol to form a 35% solution. Under stirring, spray the synthetic organic resin solution evenly onto the surface of the inorganic powder, and dry it thoroughly at 80℃ to obtain the modified inorganic powder.

[0076] Modification of expandable polystyrene:

[0077] Weigh out 100 parts of expandable polystyrene and 3 parts of silane coupling agent according to the mass percentage. Dissolve the silane coupling agent in anhydrous ethanol to form a 30% solution. Under stirring, spray the silane coupling agent solution evenly onto the surface of the expandable polystyrene and dry it thoroughly at 80°C to obtain modified expandable polystyrene.

[0078] Low-density biomass fiber-based boards are hot-pressed into shape:

[0079] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene were mixed evenly according to a mass ratio of 6:2:1. The mixture was then placed into a mold and placed in a flat vulcanizing machine. The mold was hot-pressed at 120°C and 15MPa for 70 minutes to obtain the low-density biomass fiber-based board.

[0080] Surface coating of low-density biomass fiber-based boards:

[0081] Epoxy resin, benzyl alcohol, and diethylenetriamine were weighed out in a mass ratio of 10:1:1. The epoxy resin was dissolved in benzyl alcohol, and the diethylenetriamine was added and stirred thoroughly to obtain an epoxy resin adhesive. The epoxy resin adhesive was evenly applied to the surface of a low-density biomass fiber-based board, and a facing paper was laid on top. Then, the epoxy resin adhesive was evenly applied to the surface of the facing paper, and a wear-resistant layer was laid on top. The biomass fiber-based board with the facing paper and wear-resistant layer was placed in a flat vulcanizing machine and hot-pressed at 80℃ and 5MPa for 30 minutes. After removal, it was allowed to stand and cure for 3 days to obtain the biomass fiber high-filling thermal insulation and flame-retardant decorative wall panel.

[0082] Example 4

[0083] The corn stalks are washed and dried, then crushed into fiber powder smaller than 5 mm using a pulverizer. The fiber powder is then soaked in an alkaline aqueous solution with a pH of 11 for 2 days, and then heated at 110℃ for 15 hours to obtain pretreated biomass fiber.

[0084] Organic resin synthesis: According to the mass percentage, weigh 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 2.5 parts of dibutyltin dilaurate, and 10.5 parts of aminopropyltriethoxysilane. Add polycaprolactone diol and dibutyltin dilaurate sequentially to a three-necked flask, stir evenly under nitrogen protection, and heat to 80°C. While stirring continuously, slowly add maleic anhydride to the three-necked flask, and continue stirring for 1 hour under nitrogen protection and 80°C. Lower the reaction temperature to 30°C, and slowly add aminopropyltriethoxysilane dropwise under rapid stirring, and continue stirring for 1 hour to obtain the synthetic organic resin containing siloxane end groups.

[0085] Biomass fiber modification: Weigh 100 parts of the pretreated biomass fiber and 12.5 parts of synthetic organic resin according to the mass percentage; dissolve the synthetic organic resin in anhydrous ethanol to form a 30% solution. Under stirring, uniformly spray the synthetic organic resin solution onto the surface of the biomass fiber and dry it thoroughly at 80°C to obtain the modified biomass fiber.

[0086] Surface modification of inorganic mineral powder: Weigh out 100 parts by mass of magnesium hydroxide, 100 parts by mass of calcium chloride, and 26 parts by mass of synthetic organic resin. Mix magnesium hydroxide and calcium chloride evenly, and dissolve the synthetic organic resin in anhydrous ethanol to form a 32% solution. Under stirring, spray the synthetic organic resin solution evenly onto the surface of the inorganic powder and dry it thoroughly at 80°C to obtain the modified inorganic powder.

[0087] Modification of expandable polystyrene:

[0088] Weigh out 100 parts of expandable polystyrene and 3 parts of silane coupling agent according to the mass percentage. Dissolve the silane coupling agent in anhydrous ethanol to form a 30% solution. Under stirring, spray the silane coupling agent solution evenly onto the surface of the expandable polystyrene and dry it thoroughly at 80°C to obtain modified expandable polystyrene.

[0089] Low-density biomass fiber-based boards are hot-pressed into shape:

[0090] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene were mixed evenly according to a mass ratio of 6:2:1. The mixture was then placed into a mold and placed in a flat vulcanizing machine. The mold was hot-pressed at 120°C and 15MPa for 70 minutes to obtain the low-density biomass fiber-based board.

[0091] Surface coating of low-density biomass fiber-based boards:

[0092] Epoxy resin, benzyl alcohol, and diethylenetriamine were weighed out in a mass ratio of 10:1:1. The epoxy resin was dissolved in benzyl alcohol, and the diethylenetriamine was added and stirred thoroughly to obtain an epoxy resin adhesive. The epoxy resin adhesive was evenly applied to the surface of a low-density biomass fiber-based board, and a facing paper was laid on top. Then, the epoxy resin adhesive was evenly applied to the surface of the facing paper, and a wear-resistant layer was laid on top. The biomass fiber-based board with the facing paper and wear-resistant layer was placed in a flat vulcanizing machine and hot-pressed at 80℃ and 5MPa for 30 minutes. After removal, it was allowed to stand and cure for 3 days to obtain the biomass fiber high-filling thermal insulation and flame-retardant decorative wall panel.

[0093] Example 5

[0094] Wheat straw is washed and dried, then crushed into fiber powder smaller than 5mm using a pulverizer. The fiber powder is then soaked in an alkaline aqueous solution with a pH of 11 for 2 days, and then heated at 115℃ for 14 hours to obtain pretreated biomass fiber.

[0095] Organic resin synthesis: According to the mass percentage, weigh 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 2.5 parts of dibutyltin dilaurate, and 11.5 parts of aminopropyltriethoxysilane. Add polycaprolactone diol and dibutyltin dilaurate sequentially to a three-necked flask, stir evenly under nitrogen protection, and heat to 80°C. While stirring continuously, slowly add maleic anhydride to the three-necked flask, and continue stirring for 1 hour under nitrogen protection and 80°C. Lower the reaction temperature to 30°C, and slowly add aminopropyltriethoxysilane dropwise under rapid stirring, and continue stirring for 1 hour to obtain the synthetic organic resin containing siloxane end groups.

[0096] Biomass fiber modification: Weigh 100 parts of the pretreated biomass fiber and 14 parts of synthetic organic resin according to the mass percentage; dissolve the synthetic organic resin in anhydrous ethanol to form a 28% solution. Under stirring, uniformly spray the synthetic organic resin solution onto the surface of the biomass fiber and dry it thoroughly at 80°C to obtain the modified biomass fiber.

[0097] Surface modification of inorganic mineral powder: Weigh out 100 parts by mass of magnesium hydroxide, 100 parts by mass of calcium chloride, and 27 parts by mass of synthetic organic resin. Mix magnesium hydroxide and calcium chloride evenly, and dissolve the synthetic organic resin in anhydrous ethanol to form a 28% solution. Under stirring, spray the synthetic organic resin solution evenly onto the surface of the inorganic powder and dry it thoroughly at 80℃ to obtain the modified inorganic powder.

[0098] Modification of expandable polystyrene:

[0099] Weigh out 100 parts of expandable polystyrene and 3 parts of silane coupling agent according to the mass percentage. Dissolve the silane coupling agent in anhydrous ethanol to form a 30% solution. Under stirring, spray the silane coupling agent solution evenly onto the surface of the expandable polystyrene and dry it thoroughly at 80°C to obtain modified expandable polystyrene.

[0100] Low-density biomass fiber-based boards are hot-pressed into shape:

[0101] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene were mixed evenly according to a mass ratio of 6:2:1. The mixture was then placed into a mold and placed in a flat vulcanizing machine. The mold was hot-pressed at 120°C and 15MPa for 70 minutes to obtain the low-density biomass fiber-based board.

[0102] Surface coating of low-density biomass fiber-based boards:

[0103] Epoxy resin, benzyl alcohol, and diethylenetriamine were weighed out in a mass ratio of 10:1:1. The epoxy resin was dissolved in benzyl alcohol, and the diethylenetriamine was added and stirred thoroughly to obtain an epoxy resin adhesive. The epoxy resin adhesive was evenly applied to the surface of a low-density biomass fiber-based board, and a facing paper was laid on top. Then, the epoxy resin adhesive was evenly applied to the surface of the facing paper, and a wear-resistant layer was laid on top. The biomass fiber-based board with the facing paper and wear-resistant layer was placed in a flat vulcanizing machine and hot-pressed at 80℃ and 5MPa for 30 minutes. After removal, it was allowed to stand and cure for 3 days to obtain the biomass fiber high-filling thermal insulation and flame-retardant decorative wall panel.

[0104] The performance of the biomass fiber high-filling thermal insulation and flame-retardant decorative wall panels obtained in Examples 1-5 was tested, and the results are shown in Table 1:

[0105] Table 1 Performance test data of the thermal insulation and flame-retardant decorative wall panels prepared in Examples 1-5

[0106] Example 1 42.8±0.7 8.7±0.3 68.2±2.5 Example 2 40.1±0.5 9.3±0.6 78.5±1.9 Example 3 33.4±1.1 10.8±0.4 73.0±1.7 Example 4 39.6±0.6 9.4±0.5 70.9±2.1 Example 5 37.4±0.9 10.1±0.2 74.5±1.4

[0107] As shown in Table 1, from the perspective of flame retardant performance, the limiting oxygen index (LOI) of Examples 1 to 5 is greater than 32%. In the event of a fire, these wall panels can effectively slow the spread of fire, buying valuable time for evacuation and fire rescue, thereby greatly improving the overall fire safety performance of the building. Secondly, in terms of impact resistance, the impact strength of Examples 1 to 5 is all above 8 KJ / m. 2 In summary, these materials can withstand various external impacts, such as collisions and vibrations, without easily breaking or deforming. This not only extends the service life of the wall panels but also ensures their stability and integrity during use, thus providing users with a more reliable user experience. Finally, the surface hardness of Examples 1 to 5 all exceed 65°, resulting in a relatively hard surface texture that is not easily scratched or worn. The hard surface better resists friction and collisions during daily use, keeping the wall panels clean and intact, while also reducing the cost of later maintenance and upkeep.

[0108] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for preparing a biomass fiber-filled, heat-insulating, flame-retardant decorative wall panel, characterized in that, Specifically, the following steps are included: Epoxy resin adhesive is evenly applied to the surface of the biomass fiber-based board, and then decorative paper is laid on it; epoxy resin adhesive is evenly applied to the surface of the decorative paper, and then a wear-resistant layer is laid on it; the base board with the decorative paper and wear-resistant layer is placed in a flat vulcanizing machine, hot-pressed and statically cured to obtain the biomass fiber high-filling heat-insulating and flame-retardant decorative wall panel. The preparation method of the biomass fiber-based board includes the following steps: Modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed evenly. The mixture is then loaded into a mold and placed into a flat vulcanizing machine. After hot pressing, the biomass fiber-based board is obtained. The preparation method of the modified biomass fiber specifically includes the following steps: The synthetic organic resin is dissolved in anhydrous ethanol to form a 20%~30% solution. The synthetic organic resin solution is then uniformly sprayed onto the surface of the pretreated biomass fiber and dried to obtain the modified biomass fiber. The method for preparing the pretreated biomass fiber includes the following steps: The crop straw is washed and dried, then crushed into fiber powder smaller than 5 mm using a pulverizer. The fiber powder is then soaked in an alkaline aqueous solution for 2-3 days and heated at 100-120℃ for 12-24 hours to obtain pretreated biomass fiber. The preparation method of the modified inorganic powder specifically includes the following steps: Magnesium hydroxide and calcium chloride are mixed evenly, and the synthetic organic resin is dissolved in anhydrous ethanol to form a 25%~35% solution; under stirring, the synthetic organic resin solution is evenly sprayed onto the surface of the inorganic powder and dried thoroughly at 60~80℃ to obtain the modified inorganic powder. The method for preparing the synthetic organic resin includes the following steps: Polycaprolactone diol and dibutyltin dilaurate were stirred evenly under nitrogen protection and heated to 40-80°C; maleic anhydride was then added, and the reaction was continued to be stirred for 1-3 hours under nitrogen protection; the reaction temperature was lowered to 10-30°C, aminopropyltriethoxysilane was added, and the reaction was continued to be stirred for 1-3 hours to obtain a synthetic organic resin containing siloxane end groups. The preparation method of the modified expandable polystyrene specifically includes the following steps: A 20-30% solution of silane coupling agent is dissolved in anhydrous ethanol. The silane coupling agent solution is then uniformly sprayed onto the surface of expandable polystyrene and dried to obtain modified expandable polystyrene.

2. The method for preparing a biomass fiber highly filled thermal insulation and flame-retardant decorative wall panel according to claim 1, characterized in that, The preparation method of the epoxy resin adhesive specifically includes the following steps: Epoxy resin is dissolved in benzyl alcohol, diethylenetriamine is added and stirred thoroughly to obtain an epoxy resin adhesive; the mass ratio of epoxy resin, benzyl alcohol and diethylenetriamine is 10:1:

1.

3. The method for preparing a biomass fiber highly filled thermal insulation and flame-retardant decorative wall panel according to claim 1, characterized in that, The mass ratio of the modified biomass fiber, modified inorganic powder, and modified expandable polystyrene is (5~6):2:

1.

4. The method for preparing a biomass fiber highly filled thermal insulation and flame-retardant decorative wall panel according to claim 1, characterized in that, The mass ratio of polycaprolactone diol, maleic anhydride, dibutyltin dilaurate and aminopropyltriethoxysilane is 100:20:(2~3):(10~12).