Preparation method of thermal-insulation flame-retardant decorative wallboard highly filled with biomass fibers

Abstract

The invention belongs to the field of building materials, and particularly relates to a preparation method of a biomass fiber highly-filled thermal-insulation flame-retardant decorative wallboard. The method specifically comprises the following steps: uniformly coating the surface of a biomass fiber-based plate with an epoxy resin adhesive, and paving facing paper; uniformly coating the epoxy resin adhesive on the surface of the facing paper, and paving the wear-resistant layer; and putting the base plate on which the facing paper and the wear-resistant layer are laid into a press vulcanizer, and performing hot pressing and standing maintenance to obtain the biomass fiber highly-filled thermal-insulation flame-retardant decorative wallboard. The strong bonding among the materials is realized, and the overall stability and durability of the wallboard are improved; and heat preservation and flame retardance are enhanced through a multi-layer structure, and use safety is ensured.

Description

Technical Field

[0001] The invention belongs to the field of building materials, and in particular relates to a method for preparing a heat-insulating and flame-retardant decorative wallboard with high biomass fiber filling. Background Art

[0002] As people's requirements for the aesthetics, safety and environmental protection of their living environment are increasing, traditional wooden decorative panels have occupied a place in the market due to their natural texture and good decorative effect. However, their inherent flammability and moisture resistance have become the key factors restricting their widespread application. Especially in modern home environments, the importance of fire safety and indoor air quality has become increasingly prominent, prompting the industry to continuously explore new and high-performance decorative materials.

[0003] Traditional wooden decorative panels also have two prominent disadvantages: one is that they are flammable, and if fire prevention measures are not in place, fires can easily occur. For families who often use open flames, wooden wall decoration poses a great safety hazard; the other is that they are not moisture-resistant and are prone to mold in a high humidity environment, which not only affects the appearance, but also affects the indoor air quality and causes harm to human health. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling. The base material of the thermal insulation decorative wallboard developed by the present invention with biomass fiber as the main raw material has the advantages of excellent thermal insulation performance, green zero formaldehyde, fireproof and moisture-proof, and good dimensional stability. After coating or coating the surface decorative layer, various building thermal insulation decorative wallboards can be formed. It can efficiently utilize plant stem fibers such as agricultural waste straw to prepare low-carbon new material base materials to replace the original natural wood, thereby greatly reducing the consumption of forest resources in the decoration industry chain.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a method for preparing a heat-insulating and flame-retardant decorative wallboard with high biomass fiber filling, which specifically comprises the following steps:

[0007] The epoxy resin adhesive is evenly applied on the surface of the biomass fiber base board, and the facing paper is laid; the epoxy resin adhesive is evenly applied on the surface of the facing paper, and a wear-resistant layer is laid; the base board with the facing paper and the wear-resistant layer is placed in a flat vulcanizer, hot-pressed and statically cured to obtain the biomass fiber-filled thermal insulation and flame-retardant decorative wallboard.

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

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

[0010] Preferably, the method for preparing the biomass fiber-based board comprises the following steps:

[0011] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed evenly, the mixed material is loaded into a mold, and the mold is placed in a flat vulcanizer, and the biomass fiber-based board is obtained after hot pressing.

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

[0013] Preferably, the method for preparing the modified biomass fiber specifically comprises the following steps:

[0014] The synthetic organic resin is dissolved in anhydrous ethanol to form a 20% to 30% solution, and the synthetic organic resin solution is evenly sprayed on the surface of the pretreated biomass fiber, and the modified biomass fiber is obtained after drying.

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

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

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

[0018] The 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 on the surface of the inorganic powder, and fully dried at 60 to 80° C. to obtain the modified inorganic powder.

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

[0020] The polycaprolactone diol and dibutyltin dilaurate are stirred evenly under nitrogen protection and the temperature is raised to 40-80°C; maleic anhydride is then added, and the reaction is continued with stirring for 1-3 hours under nitrogen protection; the reaction temperature is lowered to 10-30°C, aminopropyltriethoxysilane is added, and the reaction is continued with stirring for 1-3 hours to obtain a synthetic organic resin containing siloxane end groups.

[0021] Preferably, the mass ratio of the 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 comprises the following steps:

[0023] The silane coupling agent is dissolved in anhydrous ethanol to form a 20-30% solution, and the silane coupling agent solution is evenly sprayed on the surface of expandable polystyrene, and the modified expandable polystyrene is obtained after drying.

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

[0025] The present invention adopts epoxy resin adhesive combined with biomass fiber base material, facing paper and wear-resistant layer to make thermal insulation and flame retardant decorative wall panels, which not only realizes strong adhesion between materials and improves the overall stability and durability of the wall panels; it also enhances the thermal insulation and flame retardant properties through a multi-layer structure to ensure safe use; at the same time, the beautiful facing paper and wear-resistant layer give the wall panels good decorative effects and wear resistance; in addition, the main raw material of the product of the present invention, crop straw, is widely available and low in cost, and can greatly reduce the consumption of forest resources in the decoration industry chain, which can promote the recycling of resources in the building decoration industry. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only embodiments of a part of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work 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 "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

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

[0029] It should be further understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0030] The present invention achieves flame retardancy of the base board by adding a certain proportion of inorganic powders such as calcium chloride and magnesium hydroxide to the biomass fiber; at the same time, in order to make the organic biomass fiber and the inorganic mineral component have a strong bonding force and improve the moisture-proof ability of the base board, the present invention uses a directional synthesized organic resin to perform organic-inorganic hybrid modification on the material. In the composite process of biomass fiber, organic synthetic resin and inorganic mineral powder, the moisture content and other undesirable components of the biomass fiber will have a great impact on the organic-inorganic hybrid modification. Too high a moisture content will lead to defects such as voids or internal stress inside the base board, while the biomass fiber in a completely dry state is relatively brittle, and the shear stress of the molding process will cut the fiber; at the same time, the biomass fiber may also have some undesirable components that affect its surface grafting modification, such as lignin. Therefore, it is necessary to pretreat the biomass fiber to remove excess moisture and other undesirable components.

[0031] There are three commonly used methods for treating biomass fibers: acid soaking treatment, alkali soaking treatment and heat treatment; the present invention optimizes the pretreatment process through experiments: firstly, the biomass fibers are soaked in alkali, and the pH range and soaking time are controlled to remove lignin to the maximum extent while fully ensuring that the cellulose and hemicellulose in the raw materials are not destroyed; after the raw materials soaked in alkali are cleaned, the reasonable temperature and time are controlled to controllably remove the moisture and other volatile substances in the biomass fibers, thereby improving the mechanical properties and surface characteristics of the biomass fiber raw materials.

[0032] The present invention provides a method for preparing a heat-insulating flame-retardant decorative wallboard with high biomass fiber filling, which is characterized by comprising the following steps:

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

[0034] Synthesis of organic resin: According to the mass percentage, weigh 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 2-3 parts of dibutyltin dilaurate, and 10-12 parts of aminopropyl triethoxysilane respectively; add polycaprolactone diol and dibutyltin dilaurate in a three-necked flask in turn, stir evenly under nitrogen protection, and heat to 40-80°C. Under continuous stirring, slowly add maleic anhydride to the above three-necked flask, and continue stirring and reacting for 1-3 hours under nitrogen protection and 40-80°C; reduce the reaction temperature to 10-30°C, slowly drop aminopropyl triethoxysilane under rapid stirring, and continue stirring and reacting for 1-3 hours to obtain a synthetic organic resin containing siloxane end groups. Among them, maleic anhydride can be replaced by dicarboxylic anhydrides such as succinic anhydride or glutaric anhydride.

[0035] Biomass fiber modification: According to the mass percentage, weigh 100 parts of the above-mentioned pretreated biomass fiber and 12-15 parts of the synthetic organic resin respectively; dissolve the synthetic organic resin in anhydrous ethanol to form a 20%-30% solution. Under stirring, spray the synthetic organic resin solution evenly on the surface of the biomass fiber, and fully dry it at 60-80°C to obtain the modified biomass fiber.

[0036] Surface modification of inorganic mineral powder: According to the mass percentage, weigh 100 parts of magnesium hydroxide, 100 parts of calcium chloride, and 25-30 parts of synthetic organic resin respectively. 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 on the surface of the inorganic powder, and fully dry it at 60-80°C to obtain the modified inorganic powder.

[0037] Modification of expandable polystyrene:

[0038] According to the mass percentage, 100 parts of expandable polystyrene and 2-3 parts of silane coupling agent are weighed respectively, and the silane coupling agent is dissolved in anhydrous ethanol to form a 20%-30% solution. Under stirring, the silane coupling agent solution is evenly sprayed on the surface of the expandable polystyrene, and fully dried at 60-80°C to obtain modified expandable polystyrene.

[0039] Low-density biomass fiber-based board hot pressing molding:

[0040] According to the mass ratio of (5-6):2:1, the modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed uniformly; the mixed material is loaded into a mold, and the mold is placed in a flat vulcanizer, and hot-pressed for 60-70 minutes under the conditions of 110-120°C and 15-20MPa to obtain the low-density biomass fiber-based board. The biomass fiber-based board prepared by the present invention has excellent thermal insulation, fire and moisture resistance and good dimensional stability through the beneficial compounding of biomass fiber, inorganic powder, synthetic resin and expandable polystyrene.

[0041] Low-density biomass fiber-based board surface film:

[0042] According to the mass percentage of 10:1:1, epoxy resin, benzyl alcohol and diethylenetriamine are weighed respectively. Dissolve the epoxy resin in benzyl alcohol, add diethylenetriamine and stir well to obtain epoxy resin adhesive; evenly apply the epoxy resin adhesive to the surface of the low-density biomass fiber-based board, and lay the facing paper; then, evenly apply the epoxy resin adhesive to the surface of the facing paper, and lay the wear-resistant layer; put the biomass fiber-based board with the facing paper and the wear-resistant layer into a flat vulcanizer, hot press at 60-80°C and 5-8MPa for 10-30 minutes, take it out and let it stand for 2-3 days to obtain the thermal insulation and flame-retardant decorative wallboard with high biomass fiber filling; preferably, colored facing paper and PET wear-resistant layer are used. Among them, the epoxy resin adhesive can also be replaced by a light-curing resin.

[0043] The present invention has the following advantages:

[0044] (1) Pretreatment of biomass fibers: The biomass fibers are pretreated by alkali soaking followed by heating. This method does not require expensive equipment and complex modification processes, and effectively removes excess moisture, lignin, and flammable components from the biomass fibers.

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

[0046] (3) Surface modification of biomass fibers and inorganic powders: By adding an appropriate amount of synthetic organic resin, it not only ensures that the materials have strong adhesion, but also ensures that the base material has excellent flame retardant properties.

[0047] (4) Hot pressing of biomass fiber-based board materials: The base board materials of the present invention are formed by hot pressing. A large number of experiments are conducted to determine a more reasonable temperature and pressure, which fully ensures that the expandable polystyrene foams without melting, ensures that the base board materials have a lower density, and that the biomass fiber and inorganic powder in the base board materials are compacted due to the volume expansion of the expandable polystyrene.

[0048] (5) Surface filming of biomass fiber-based board material: The present invention uses an appropriate ratio of epoxy resin adhesive and a heat curing temperature to ensure that the facing paper and the wear-resistant layer are firmly attached to the surface of the biomass-based board material.

[0049] Example 1

[0050] The rice straw is washed and dried, and then crushed into fiber powder less than 5 mm by a crusher. The fiber powder is soaked in an alkaline aqueous solution with a pH of 11 for 2 days, and then heated at 100° C. for 24 hours to obtain pretreated biomass fibers.

[0051] Synthesis of organic resin: According to the mass percentage, 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 2 parts of dibutyltin dilaurate, and 10 parts of aminopropyltriethoxysilane are weighed respectively; polycaprolactone diol and dibutyltin dilaurate are added to a three-necked flask in sequence, stirred evenly under nitrogen protection, and the temperature is raised to 40°C. Under continuous stirring, maleic anhydride is slowly added to the above three-necked flask, and the reaction is continuously stirred for 3 hours under nitrogen protection and 40°C; the reaction temperature is lowered to 10°C, and aminopropyltriethoxysilane is slowly dripped under rapid stirring conditions, and the reaction is continuously stirred for 3 hours to obtain a synthetic organic resin containing siloxane end groups.

[0052] Biomass fiber modification: According to the mass percentage, weigh 100 parts of the above-mentioned pretreated biomass fiber and 12 parts of the synthetic organic resin respectively; dissolve the synthetic organic resin in anhydrous ethanol to form a 20% solution. Under stirring, spray the synthetic organic resin solution evenly on the surface of the biomass fiber, and fully dry it at 60°C to obtain the modified biomass fiber.

[0053] Surface modification of inorganic mineral powder: According to the mass percentage, weigh 100 parts of magnesium hydroxide, 100 parts of calcium chloride, and 25 parts 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% solution. Under stirring, spray the synthetic organic resin solution evenly on the surface of the inorganic powder, and fully dry it at 60°C to obtain the modified inorganic powder.

[0054] Modification of expandable polystyrene:

[0055] According to the mass percentage, 100 parts of expandable polystyrene and 2 parts of silane coupling agent are weighed respectively, and the silane coupling agent is dissolved in anhydrous ethanol to form a 20% solution. Under stirring, the silane coupling agent solution is evenly sprayed on the surface of the expandable polystyrene, and fully dried at 60°C to obtain modified expandable polystyrene.

[0056] Low-density biomass fiber-based board hot pressing molding:

[0057] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed evenly according to a mass percentage of 5:2:1; the mixed material is loaded into a mold, and the mold is placed in a flat vulcanizer, and hot-pressed for 60 minutes at 110°C and 20MPa to obtain the low-density biomass fiber-based board.

[0058] Low-density biomass fiber-based board surface film:

[0059] Epoxy resin, benzyl alcohol and diethylenetriamine were weighed according to the mass percentage of 10:1:1. Epoxy resin was dissolved in benzyl alcohol, diethylenetriamine was added and stirred thoroughly to obtain epoxy resin adhesive; the epoxy resin adhesive was evenly coated on the surface of the low-density biomass fiber-based board, and the facing paper was laid; then, the epoxy resin adhesive was evenly coated on the surface of the facing paper, and a wear-resistant layer was laid; the biomass fiber-based board with the facing paper and the wear-resistant layer was placed in a flat vulcanizer, hot-pressed at 60°C and 8MPa for 10 minutes, and then taken out and cured for 2 days to obtain the thermal insulation and flame-retardant decorative wallboard with high biomass fiber filling.

[0060] Example 2

[0061] The corn stalks were washed and dried, and then crushed into fiber powder with a crusher of less than 5 mm. The fiber powder was soaked in an alkaline aqueous solution with a pH of 11 for 2 days, and then heated at 110° C. for 16 hours to obtain pretreated biomass fibers.

[0062] Synthesis of organic resin: According to the mass percentage, 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 3 parts of dibutyltin dilaurate, and 11 parts of aminopropyltriethoxysilane were weighed respectively; polycaprolactone diol and dibutyltin dilaurate were added to a three-necked flask in sequence, stirred evenly under nitrogen protection, and heated to 50°C. Under continuous stirring, maleic anhydride was slowly added to the above three-necked flask, and the reaction was continuously stirred for 2 hours under nitrogen protection and 50°C; the reaction temperature was lowered to 20°C, and aminopropyltriethoxysilane was slowly dropped under rapid stirring conditions, and the reaction was continuously stirred for 2 hours to obtain a synthetic organic resin containing siloxane end groups.

[0063] Biomass fiber modification: According to the mass percentage, weigh 100 parts of the above-mentioned pretreated biomass fiber and 14 parts of the synthetic organic resin respectively; dissolve the synthetic organic resin in anhydrous ethanol to form a 25% solution. Under stirring, spray the synthetic organic resin solution evenly on the surface of the biomass fiber, and fully dry it at 70°C to obtain the modified biomass fiber.

[0064] Surface modification of inorganic mineral powder: According to the mass percentage, weigh 100 parts of magnesium hydroxide, 100 parts of calcium chloride, and 27 parts of synthetic organic resin. Mix the 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 on the surface of the inorganic powder, and fully dry it at 70°C to obtain the modified inorganic powder.

[0065] Modification of expandable polystyrene:

[0066] According to the mass percentage, 100 parts of expandable polystyrene and 3 parts of silane coupling agent are weighed respectively, and the silane coupling agent is dissolved in anhydrous ethanol to form a 25% solution. Under stirring, the silane coupling agent solution is evenly sprayed on the surface of the expandable polystyrene, and fully dried at 70°C to obtain modified expandable polystyrene.

[0067] Low-density biomass fiber-based board hot pressing molding:

[0068] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed evenly according to a mass percentage of 5.5:2:1; the mixed material is loaded into a mold, and the mold is placed in a flat vulcanizer, and hot-pressed for 65 minutes at 115°C and 18MPa to obtain the low-density biomass fiber-based board.

[0069] Low-density biomass fiber-based board surface film:

[0070] Epoxy resin, benzyl alcohol and diethylenetriamine were weighed according to the mass percentage of 10:1:1. Epoxy resin was dissolved in benzyl alcohol, diethylenetriamine was added and stirred thoroughly to obtain epoxy resin adhesive; the epoxy resin adhesive was evenly coated on the surface of the low-density biomass fiber-based board, and the facing paper was laid; then, the epoxy resin adhesive was evenly coated on the surface of the facing paper, and a wear-resistant layer was laid; the biomass fiber-based board with the facing paper and the wear-resistant layer was placed in a flat vulcanizer, hot-pressed at 70°C and 7MPa for 20 minutes, and then taken out and cured for 3 days to obtain the thermal insulation and flame-retardant decorative wallboard with high biomass fiber filling.

[0071] Example 3

[0072] The wheat straw is washed and dried, and then crushed into fiber powder less than 5 mm by a crusher. The fiber powder is soaked in an alkaline aqueous solution with a pH of 11 for 3 days, and then heated at 120° C. for 12 hours to obtain pretreated biomass fibers.

[0073] Synthesis of organic resin: According to the mass percentage, 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 3 parts of dibutyltin dilaurate, and 12 parts of aminopropyltriethoxysilane are weighed respectively; polycaprolactone diol and dibutyltin dilaurate are added to a three-necked flask in sequence, stirred evenly under nitrogen protection, and the temperature is raised to 80°C. Under continuous stirring, maleic anhydride is slowly added to the above three-necked flask, and the reaction is continuously stirred at 80°C for 1 hour under nitrogen protection; the reaction temperature is lowered to 30°C, and aminopropyltriethoxysilane is slowly dripped under rapid stirring conditions, and the reaction is continuously stirred for 1 hour to obtain a synthetic organic resin containing siloxane end groups.

[0074] Biomass fiber modification: According to the mass percentage, weigh 100 parts of the above-mentioned pretreated biomass fiber and 15 parts of the synthetic organic resin respectively; dissolve the synthetic organic resin in anhydrous ethanol to form a 30% solution. Under stirring, spray the synthetic organic resin solution evenly on the surface of the biomass fiber, and fully dry it at 80°C to obtain the modified biomass fiber.

[0075] Surface modification of inorganic mineral powder: According to the mass percentage, weigh 100 parts of magnesium hydroxide, 100 parts of calcium chloride, and 30 parts of synthetic organic resin. Mix the 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 on the surface of the inorganic powder, and fully dry it at 80°C to obtain the modified inorganic powder.

[0076] Modification of expandable polystyrene:

[0077] According to the mass percentage, 100 parts of expandable polystyrene and 3 parts of silane coupling agent are weighed respectively, and the silane coupling agent is dissolved in anhydrous ethanol to form a 30% solution. Under stirring, the silane coupling agent solution is evenly sprayed on the surface of the expandable polystyrene, and fully dried at 80°C to obtain modified expandable polystyrene.

[0078] Low-density biomass fiber-based board hot pressing molding:

[0079] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed evenly according to a mass percentage of 6:2:1; the mixed material is loaded into a mold, and the mold is placed in a flat vulcanizer, and hot-pressed for 70 minutes at 120°C and 15MPa to obtain the low-density biomass fiber-based board.

[0080] Low-density biomass fiber-based board surface film:

[0081] Epoxy resin, benzyl alcohol and diethylenetriamine were weighed according to the mass percentage of 10:1:1. Epoxy resin was dissolved in benzyl alcohol, diethylenetriamine was added and stirred thoroughly to obtain epoxy resin adhesive; the epoxy resin adhesive was evenly coated on the surface of the low-density biomass fiber-based board, and the facing paper was laid; then, the epoxy resin adhesive was evenly coated on the surface of the facing paper, and a wear-resistant layer was laid; the biomass fiber-based board with the facing paper and the wear-resistant layer was placed in a flat vulcanizer, hot-pressed at 80°C and 5MPa for 30 minutes, and then taken out and cured for 3 days to obtain the thermal insulation and flame-retardant decorative wallboard with high biomass fiber filling.

[0082] Example 4

[0083] The corn stalks were washed and dried, and then crushed into fiber powder with a crusher of less than 5 mm. The fiber powder was soaked in an alkaline aqueous solution with a pH of 11 for 2 days, and then heated at 110° C. for 15 hours to obtain pretreated biomass fibers.

[0084] Synthesis of organic resin: According to the mass percentage, 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 2.5 parts of dibutyltin dilaurate, and 10.5 parts of aminopropyltriethoxysilane are weighed respectively; polycaprolactone diol and dibutyltin dilaurate are added to a three-necked flask in sequence, stirred evenly under nitrogen protection, and the temperature is raised to 80°C. Under continuous stirring, maleic anhydride is slowly added to the above three-necked flask, and the reaction is continuously stirred for 1 hour under nitrogen protection and 80°C; the reaction temperature is lowered to 30°C, and aminopropyltriethoxysilane is slowly dripped under rapid stirring conditions, and the reaction is continuously stirred for 1 hour to obtain a synthetic organic resin containing siloxane end groups.

[0085] Biomass fiber modification: According to the mass percentage, weigh 100 parts of the above-mentioned pretreated biomass fiber and 12.5 parts of the synthetic organic resin respectively; dissolve the synthetic organic resin in anhydrous ethanol to form a 30% solution. Under stirring, spray the synthetic organic resin solution evenly on the surface of the biomass fiber, and fully dry it at 80°C to obtain the modified biomass fiber.

[0086] Surface modification of inorganic mineral powder: According to the mass percentage, weigh 100 parts of magnesium hydroxide, 100 parts of calcium chloride, and 26 parts of synthetic organic resin. Mix the 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 on the surface of the inorganic powder, and fully dry it at 80°C to obtain the modified inorganic powder.

[0087] Modification of expandable polystyrene:

[0088] According to the mass percentage, 100 parts of expandable polystyrene and 3 parts of silane coupling agent are weighed respectively, and the silane coupling agent is dissolved in anhydrous ethanol to form a 30% solution. Under stirring, the silane coupling agent solution is evenly sprayed on the surface of the expandable polystyrene, and fully dried at 80°C to obtain modified expandable polystyrene.

[0089] Low-density biomass fiber-based board hot pressing molding:

[0090] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed evenly according to a mass percentage of 6:2:1; the mixed material is loaded into a mold, and the mold is placed in a flat vulcanizer, and hot-pressed for 70 minutes at 120°C and 15MPa to obtain the low-density biomass fiber-based board.

[0091] Low-density biomass fiber-based board surface film:

[0092] Epoxy resin, benzyl alcohol and diethylenetriamine were weighed according to the mass percentage of 10:1:1. Epoxy resin was dissolved in benzyl alcohol, diethylenetriamine was added and stirred thoroughly to obtain epoxy resin adhesive; the epoxy resin adhesive was evenly coated on the surface of the low-density biomass fiber-based board, and the facing paper was laid; then, the epoxy resin adhesive was evenly coated on the surface of the facing paper, and a wear-resistant layer was laid; the biomass fiber-based board with the facing paper and the wear-resistant layer was placed in a flat vulcanizer, hot-pressed at 80°C and 5MPa for 30 minutes, and then taken out and cured for 3 days to obtain the thermal insulation and flame-retardant decorative wallboard with high biomass fiber filling.

[0093] Example 5

[0094] The wheat straw was washed and dried, and then crushed into fiber powder less than 5 mm by a crusher. The fiber powder was soaked in an alkaline aqueous solution with a pH of 11 for 2 days, and then heated at 115° C. for 14 hours to obtain pretreated biomass fiber.

[0095] Synthesis of organic resin: According to the mass percentage, 100 parts of polycaprolactone diol, 20 parts of maleic anhydride, 2.5 parts of dibutyltin dilaurate, and 11.5 parts of aminopropyltriethoxysilane are weighed respectively; polycaprolactone diol and dibutyltin dilaurate are added to a three-necked flask in sequence, stirred evenly under nitrogen protection, and the temperature is raised to 80°C. Under continuous stirring, maleic anhydride is slowly added to the above three-necked flask, and the reaction is continuously stirred for 1 hour under nitrogen protection and 80°C; the reaction temperature is lowered to 30°C, and aminopropyltriethoxysilane is slowly dripped under rapid stirring conditions, and the reaction is continuously stirred for 1 hour to obtain a synthetic organic resin containing siloxane end groups.

[0096] Biomass fiber modification: According to the mass percentage, weigh 100 parts of the above-mentioned pretreated biomass fiber and 14 parts of the synthetic organic resin respectively; dissolve the synthetic organic resin in anhydrous ethanol to form a 28% solution. Under stirring, spray the synthetic organic resin solution evenly on the surface of the biomass fiber, and fully dry it at 80°C to obtain the modified biomass fiber.

[0097] Surface modification of inorganic mineral powder: According to the mass percentage, weigh 100 parts of magnesium hydroxide, 100 parts of calcium chloride, and 27 parts of synthetic organic resin. Mix the 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 on the surface of the inorganic powder, and fully dry it at 80°C to obtain the modified inorganic powder.

[0098] Modification of expandable polystyrene:

[0099] According to the mass percentage, 100 parts of expandable polystyrene and 3 parts of silane coupling agent are weighed respectively, and the silane coupling agent is dissolved in anhydrous ethanol to form a 30% solution. Under stirring, the silane coupling agent solution is evenly sprayed on the surface of the expandable polystyrene, and fully dried at 80°C to obtain modified expandable polystyrene.

[0100] Low-density biomass fiber-based board hot pressing molding:

[0101] The modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed evenly according to a mass percentage of 6:2:1; the mixed material is loaded into a mold, and the mold is placed in a flat vulcanizer, and hot-pressed for 70 minutes at 120°C and 15MPa to obtain the low-density biomass fiber-based board.

[0102] Low-density biomass fiber-based board surface film:

[0103] Epoxy resin, benzyl alcohol and diethylenetriamine were weighed according to the mass percentage of 10:1:1. Epoxy resin was dissolved in benzyl alcohol, diethylenetriamine was added and stirred thoroughly to obtain epoxy resin adhesive; the epoxy resin adhesive was evenly coated on the surface of the low-density biomass fiber-based board, and the facing paper was laid; then, the epoxy resin adhesive was evenly coated on the surface of the facing paper, and a wear-resistant layer was laid; the biomass fiber-based board with the facing paper and the wear-resistant layer was placed in a flat vulcanizer, hot-pressed at 80°C and 5MPa for 30 minutes, and then taken out and cured for 3 days to obtain the thermal insulation and flame-retardant decorative wallboard with high biomass fiber filling.

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

[0105] Table 1 Performance test data of thermal insulation and flame retardant decorative wallboards prepared in Examples 1 to 5

[0106] Example Limiting oxygen index (%) <![CDATA[Impact strength (KJ / m 2 )]]> Surface hardness(°) 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 retardancy, the limiting oxygen index (LOI) of Examples 1 to 5 is greater than 32%. When a fire occurs, these wall panels can effectively slow down the spread of the fire, buying valuable time for personnel 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 8KJ / m 2 As mentioned above, it can withstand various impact forces from the outside, such as collisions, vibrations, etc., and is not easy to be damaged or deformed, which not only extends the service life of the wallboard, but also ensures that it can maintain stability and integrity during use, thereby providing users with a more reliable use experience. Finally, the surface hardness of Examples 1 to 5 is more than 65°, the surface texture is relatively hard, and it is not easy to be scratched or worn. The hard surface can better resist friction and collision in daily use, keep the appearance of the wallboard neat and intact, and also reduce the cost of later maintenance and upkeep.

[0108] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling, characterized in that: The specific steps include: The epoxy resin adhesive is evenly applied on the surface of the biomass fiber base board, and the facing paper is laid; the epoxy resin adhesive is evenly applied on the surface of the facing paper, and a wear-resistant layer is laid; the base board with the facing paper and the wear-resistant layer is placed in a flat vulcanizer, hot-pressed and statically cured to obtain the biomass fiber-filled thermal insulation and flame-retardant decorative wallboard.

2. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 1, characterized in that: The preparation method of the epoxy resin adhesive specifically comprises the following steps: The epoxy resin is dissolved in benzyl alcohol, diethylenetriamine is added and stirred evenly to obtain an epoxy resin adhesive; the mass ratio of the epoxy resin, benzyl alcohol and diethylenetriamine is 10:1:

1.

3. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 1, characterized in that: The method for preparing the biomass fiber-based board comprises the following steps: The modified biomass fiber, modified inorganic powder and modified expandable polystyrene are stirred and mixed evenly, the mixed material is loaded into a mold, and the mold is placed in a flat vulcanizer, and the biomass fiber-based board is obtained after hot pressing.

4. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 3, characterized in that: The mass ratio of the modified biomass fiber, the modified inorganic powder and the modified expandable polystyrene is (5-6):2:

1.

5. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 3, characterized in that: The preparation method of the modified biomass fiber specifically comprises the following steps: The synthetic organic resin is dissolved in anhydrous ethanol to form a 20% to 30% solution, and the synthetic organic resin solution is evenly sprayed on the surface of the pretreated biomass fiber, and the modified biomass fiber is obtained after drying.

6. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 5, characterized in that: The method for preparing the pretreated biomass fiber comprises the following steps: The crop straw is washed and dried, and then crushed into fiber powder with a crusher less than 5 mm. The fiber powder is soaked in an alkaline aqueous solution for 2 to 3 days, and heated at 100-120° C. for 12 to 24 hours to obtain pretreated biomass fibers.

7. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 3, characterized in that: The preparation method of the modified inorganic powder specifically comprises the following steps: The 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 on the surface of the inorganic powder, and fully dried at 60 to 80° C. to obtain the modified inorganic powder.

8. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 5 or 7, characterized in that: The preparation method of the synthetic organic resin comprises the following steps: The polycaprolactone diol and dibutyltin dilaurate are stirred evenly under nitrogen protection and the temperature is raised to 40-80°C; maleic anhydride is then added, and the reaction is continued with stirring for 1-3 hours under nitrogen protection; the reaction temperature is lowered to 10-30°C, aminopropyltriethoxysilane is added, and the reaction is continued with stirring for 1-3 hours to obtain a synthetic organic resin containing siloxane end groups.

9. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 8, characterized in that: The mass ratio of the polycaprolactone diol, maleic anhydride, dibutyltin dilaurate and aminopropyltriethoxysilane is 100:20:(2-3):(10-12).

10. The method for preparing a thermal insulation and flame retardant decorative wallboard with high biomass fiber filling according to claim 3, characterized in that: The preparation method of the modified expandable polystyrene specifically comprises the following steps: The silane coupling agent is dissolved in anhydrous ethanol to form a 20-30% solution, and the silane coupling agent solution is evenly sprayed on the surface of expandable polystyrene, and the modified expandable polystyrene is obtained after drying.