Process for the production of a thermally insulated biomass-based building board

Abstract

The application relates to a preparation process of a heat-insulating biomass-based building board. The preparation process of the heat-insulating biomass-based building board comprises the following steps: mixing and dispersing of biomass raw materials, fiber dissociation of the biomass raw materials, hydrogen bond recombination, board pressing, heat treatment and the like. The prepared heat-insulating biomass-based building board has heat preservation and insulation effects, and the structure is controllable and has good durability, so the heat-insulating biomass-based building board has very good application prospect in the field of building boards.

Description

Technical Field

[0001] A type of heat-insulating biomass-based building material, belonging to the field of new environmentally friendly building materials. Background Technology

[0002] In existing technologies, biomass-based building panels typically use wood fibers as the main raw material, which are then pressed together with adhesives and other additives. While these panels offer advantages in mechanical properties and environmental friendliness, they still have shortcomings in thermal insulation. Specifically, biomass-based building panels prepared using existing technologies generally have a low thermal conductivity, resulting in poor thermal insulation performance. Furthermore, some adhesives and additives used in the preparation methods may contain substances harmful to human health and the environment, failing to meet environmental protection requirements.

[0003] To address the problems of low R&D and production efficiency, high pollution during production, complex processes, and poor compatibility between temperature control performance and mechanical strength in traditional energy-saving building materials, this paper utilizes the hydrogen bond dissociation and recombination mechanism between biomass fibers, water-induced green production technology for biomass-based new thermal insulation building materials, and phase change material winding growth technology to create a new type of biomass-based building material with high temperature control performance and environmental friendliness. This significantly improves the production efficiency of biomass-based new building materials, enhances product performance, expands its application fields, and reduces environmental pollution. Summary of the Invention

[0004] In order to overcome the above-mentioned technical problems existing in the existing technical field, the purpose of this invention is to provide a preparation process for heat-insulating biomass-based building panels.

[0005] This invention provides a process for preparing a heat-insulating biomass-based building panel, specifically comprising the following steps:

[0006] Step (1) Mixing and dispersing biomass raw materials

[0007] S11 Take an appropriate amount of wood powder and crush it. After processing, dry the wood powder under certain conditions. Take the dried wood powder and sieve it to obtain biomass pellets of a certain particle size.

[0008] S12 mixes biomass pellets with an appropriate amount of water and uses a stirrer to stir thoroughly, so that the biomass pellets are fully dispersed in the water.

[0009] Step (2) Preparation of surfactant

[0010] S21 Add fatty alcohol and sulfuric acid to the reaction vessel and stir until homogeneous; then heat to a suitable temperature to carry out the esterification reaction;

[0011] S22 adds the esterification product to the polymerization reactor, then adds potassium hydroxide catalyst, and heats to a suitable temperature to carry out the polymerization reaction.

[0012] After S23 polymerization is complete, the polymerization product is added to a neutralization vessel and excess sulfuric acid is neutralized with potassium hydroxide to make the product neutral.

[0013] S24 bleachs the neutralized product to remove colored substances, then refines it by filtration and distillation to remove impurities and oligomers, thus obtaining the surfactant fatty alcohol polyoxyethylene ether.

[0014] Step (3) Fiber dissociation of biomass raw materials

[0015] S31 In the mixture of biomass pellets and water, an appropriate amount of potassium hydroxide solution is gradually added to adjust the pH value of the mixture to a suitable range, and the mixture is stirred continuously for a period of time.

[0016] Add an appropriate amount of surfactant fatty alcohol polyoxyethylene ether to S32 and stir continuously to allow the biomass fiber to gradually dissociate into smaller fiber units under the combined action of potassium hydroxide alkaline substance and surfactant.

[0017] Step (4) Hydrogen bond recombination of biomass feedstock

[0018] After the fiber dissociation is complete, an appropriate amount of polyvinylpyrrolidone is added, and the mixture is stirred continuously to allow the dissociated fiber units to recombine through interactions such as hydrogen bonds, forming a more compact network structure.

[0019] Step (5) Sheet pressing

[0020] The recombined mixture is poured into a mold and then dried at room temperature. During this process, the moisture in the mixture gradually evaporates, and the fiber units are further arranged in a tighter manner to form a biomass-based building board with a three-dimensional structure.

[0021] Step (6) Heat treatment of building materials

[0022] S61 The prepared biomass-based building panels are placed in a heat treatment furnace for preheating treatment;

[0023] S62 continues to heat the preheated board to the heat treatment temperature;

[0024] After reaching the heat treatment temperature, S63 is kept at that temperature for a certain period of time.

[0025] S64 slowly cools the insulated panels to obtain heat-insulating biomass-based building panels.

[0026] As a preferred embodiment, step (1) mixing and dispersing biomass raw materials includes S11 taking 200~350g of wood powder for crushing, drying the wood powder at 60~75℃, and sieving the dried wood powder to obtain biomass particles of 60~100 mesh; S12 mixing the biomass particles with 500~1500mL of water and stirring thoroughly with a stirrer to fully disperse the biomass particles in the water.

[0027] In this method, the crushing and sieving of wood flour helps to break large wood blocks or chips into fine wood flour particles. This step increases the surface area of ​​the wood flour, making it easier to mix and react with other raw materials. Simultaneously, the sieving process removes larger particles and impurities, ensuring the uniformity and consistency of the raw materials. This is crucial for the subsequent preparation of uniform and stable-quality thermal insulation biomass-based building panels. Thorough mixing of wood flour and water helps to form a homogeneous slurry. Water, as a mixing medium, promotes the uniform dispersion of wood flour with other raw materials, forming a stable mixture. This homogeneous slurry makes it easier to obtain a uniform board structure during subsequent molding and pressing processes, thereby improving the mechanical and thermal insulation properties of the boards.

[0028] Preferably, step (2) preparation of the surfactant includes: S21 adding 1-2g of fatty alcohol and 10-15mL of sulfuric acid to a reaction vessel and stirring evenly; then heating to 100-120℃ and carrying out esterification reaction until the alcohol conversion rate reaches more than 95%; S22 adding the esterification product to a polymerization vessel and adding 0.2-0.8g of potassium hydroxide catalyst, while heating to 140-180℃ for polymerization reaction, with a polymerization time of 2-4h; S23 after polymerization, adding the polymerization product to a neutralization vessel, neutralizing the excess sulfuric acid with potassium hydroxide, maintaining the temperature at 90-100℃, and neutralizing for 1-2h to make the product neutral; S24 bleaching the neutralized product to remove the colored substances, and then refining it by filtering and distilling to remove impurities and oligomers to obtain the surfactant fatty alcohol polyoxyethylene ether.

[0029] In this method, the surfactant fatty alcohol polyoxyethylene ether is added during the preparation of thermally insulating biomass-based building panels. This effectively reduces the interfacial tension between biomass raw materials and promotes uniform dispersion. During the mixing and dispersion process, due to this property of fatty alcohol polyoxyethylene ether, the biomass raw materials can be mixed more uniformly, avoiding problems of excessively high or low local concentrations and improving the mixing efficiency. It also enhances the interaction forces between biomass raw materials. It can form bonds with hydrophilic groups in the raw materials through hydrogen bonding and other interactions, thereby improving the overall stability of the raw materials. This bonding effect helps to form a denser panel structure during subsequent molding and pressing processes, improving the mechanical and thermal insulation properties of the panel. The addition of fatty alcohol polyoxyethylene ether also improves the surface properties of the panel. By forming a thin hydrophobic film on the panel surface, fatty alcohol polyoxyethylene ether can enhance the panel's waterproof performance, improve its durability and corrosion resistance. This helps to extend the service life of the panel and maintain stable performance in complex environments.

[0030] As a preferred embodiment, step (3) the fiber dissociation of biomass raw materials includes: S31 gradually adding 5-8g of potassium hydroxide solution to the mixture of biomass particles and water, adjusting the pH value of the mixture to 8-10, and stirring continuously for 1-2 hours; S32 adding 0.1-0.4g of surfactant fatty alcohol polyoxyethylene ether, and stirring continuously for 1-2 hours, so that the biomass fibers gradually dissociate into smaller fiber units under the combined action of the alkaline substance potassium hydroxide and the surfactant.

[0031] In this method, fiber dissociation is creatively employed during the preparation of thermally insulating biomass-based building panels. Fiber dissociation breaks down the biomass raw material into finer fibers, increasing the surface area of ​​the raw material. This helps increase the contact area between the raw material and other components, promoting subsequent mixing and reaction processes. Through fiber dissociation, the original biomass raw material is broken down into smaller fibers, which can be more uniformly dispersed in the mixture. This uniform distribution helps form a more uniform and dense panel structure during pressing, thereby improving the panel's performance. During fiber dissociation, the hydroxyl groups on the fiber surface are exposed, increasing the opportunity for hydrogen bonding with other components. The formation of hydrogen bonds helps enhance the interaction forces between fibers, improving the overall stability and thermal insulation performance of the panel. Potassium hydroxide is added during the dissociation process. As a strong alkali, it reacts with the fibers in the biomass raw material, promoting fiber dissociation. By binding with the hydroxyl groups on the fiber surface, potassium hydroxide weakens the hydrogen bonding between fibers, making them easier to break down into finer fibers. This dissociation helps improve the dispersion and mixing efficiency of the raw material, laying a good foundation for subsequent panel preparation.

[0032] Preferably, step (4) hydrogen bond recombination of biomass raw materials includes adding 0.2~0.8g of polyvinylpyrrolidone after the fiber dissociation is completed, and then continuing to stir the mixture for 2~4h, so that the dissociated fiber units can recombine through hydrogen bonds and other interactions to form a more compact network structure.

[0033] In this method, biomass fibers can form a more ordered and stable structure through hydrogen bond recombination. This helps improve the mechanical and thermal insulation properties of the board, giving it better durability and stability. Hydrogen bond recombination also strengthens the bonding force between fibers, making the board less prone to deformation or cracking under external forces. This helps improve the service life and safety of the board. Furthermore, through hydrogen bond recombination, biomass fibers can be more uniformly dispersed in the mixture, forming a more uniform board structure. This helps improve the performance consistency and stability of the board. The addition of polyvinylpyrrolidone (PVP) to the hydrogen bond recombination process, as a high-molecular-weight compound, provides multiple polar groups that can bind to hydroxyl groups on the fiber surface. These groups can tightly bind to the fiber surface, promoting hydrogen bond formation and accelerating the hydrogen bond recombination process. PPVP, by binding to the hydroxyl groups on the fiber surface, can form a stable complex. This complex enhances the stability of the fibers, making them less susceptible to thermal decomposition or chemical reactions during processing, thereby improving the quality and performance of the board.

[0034] Preferably, step (5) pressing of the board includes pouring the recombined mixture into a mold, applying a pressure of 10~60MPa, and then drying at 100~140℃ for 6~12h; during this process, the moisture in the mixture gradually evaporates and promotes the fiber units to be arranged more tightly, so as to obtain a biomass-based building board with a three-dimensional structure.

[0035] In this method, biomass raw materials are compressed into boards of a certain thickness through a pressing process. During pressing, the fibers and additives in the raw materials are tightly bound together, forming a dense internal structure. This dense structure helps improve the overall strength and stability of the boards. After pressing, the fibers in the biomass raw materials form a more robust network structure under pressure. This structure is more stable in mechanical properties, improving the tensile strength, compressive strength, and other properties of the boards. This helps produce more durable and high-performance thermal insulation building boards. During pressing, the fibers and other components in the raw materials are evenly dispersed and tightly bound together, forming a more ordered structure. This ordered structure helps reduce heat transfer and improves the thermal insulation performance of the boards. Simultaneously, pressing also gives the boards better thickness consistency and dimensional stability, resulting in better thermal insulation performance in practical applications.

[0036] Preferably, step (6) heat treatment of the building board includes: S61 placing the prepared biomass-based building board into a heat treatment furnace for preheating treatment, with the preheating temperature reaching 150~200℃ and the preheating time being 30~60min; S62 continuing to heat the preheated board at a heating rate of 5~10℃ / min to a heat treatment temperature of 200~300℃; S63 maintaining the heat treatment temperature for 30~60min after reaching the heat treatment temperature for heat preservation treatment; S64 slowly cooling the heat-preserved board to finally obtain a heat-insulated biomass-based building board.

[0037] In this method, preheating heat treatment ensures uniform heating of all parts of the board, helping to reduce stress and cracking caused by temperature changes during subsequent heat treatment. Heating accelerates the chemical reaction rate of components such as fibers in the board, improving its performance. Insulation maintains the board at the required temperature for a period, allowing fibers and additives to fully undergo chemical reactions, further enhancing performance. During insulation, fibers and additives diffuse and combine more evenly, improving structural uniformity and stability. Slow cooling reduces the risk of deformation and cracking at high temperatures, improving stability and quality. Cooling also promotes phase change processes within the board, further enhancing its performance.

[0038] The heat-insulating biomass-based building panel prepared by this invention has excellent thermal insulation properties, a controllable structure, and good durability, showing great promise for application in the field of building panels. Attached Figure Description

[0039] Figure 1 This is a process flow diagram for the preparation of a heat-insulating biomass-based building panel. Detailed Implementation

[0040] Example 1

[0041] This invention provides a process for preparing a heat-insulating biomass-based building panel, specifically comprising the following steps:

[0042] Step (1) Mixing and dispersing biomass raw materials

[0043] S11 Take 200g of wood powder and crush it. After processing, dry the wood powder at 60℃. Take the dried wood powder and sieve it to obtain 60-mesh biomass pellets.

[0044] S12 mixes the biomass pellets with 500 mL of water and stirs them thoroughly with a stirrer to ensure that the biomass pellets are fully dispersed in the water;

[0045] Step (2) Preparation of surfactant

[0046] S21 Add 1g of fatty alcohol and 10mL of sulfuric acid to the reaction vessel and stir until homogeneous; then heat to 100℃ and carry out esterification reaction until the alcohol conversion rate reaches more than 95%;

[0047] S22 adds the esterification product to the polymerization reactor, then adds 0.2g of potassium hydroxide catalyst, and heats to 140℃ to carry out the polymerization reaction for 2 hours;

[0048] After S23 polymerization is complete, the polymerization product is added to a neutralization vessel, and excess sulfuric acid is neutralized with potassium hydroxide. The temperature is maintained at 90℃, and neutralization is carried out for 1 hour to make the product neutral.

[0049] S24 bleachs the neutralized product to remove colored substances, then refines it by filtration and distillation to remove impurities and oligomers, thus obtaining the surfactant fatty alcohol polyoxyethylene ether.

[0050] Step (3) Fiber dissociation of biomass raw materials

[0051] S31 In a mixture of biomass pellets and water, 5g of potassium hydroxide solution is gradually added to adjust the pH of the mixture to 8, and the mixture is stirred continuously for 1 hour.

[0052] Add 0.1g of surfactant fatty alcohol polyoxyethylene ether to S32 and stir continuously for 1 hour to allow the biomass fiber to gradually dissociate into smaller fiber units under the combined action of potassium hydroxide alkaline substance and surfactant.

[0053] Step (4) Hydrogen bond recombination of biomass feedstock

[0054] After the fiber dissociation is complete, 0.2g of polyvinylpyrrolidone is added, and the mixture is stirred for 2 hours to allow the dissociated fiber units to recombine through interactions such as hydrogen bonds, forming a more compact network structure.

[0055] Step (5) Sheet pressing

[0056] The recombined mixture is poured into a mold, a pressure of 10 MPa is applied, and then dried at 100°C for 6 hours. During this process, the moisture in the mixture gradually evaporates, and the fiber units are further arranged in a tighter manner to obtain a biomass-based building board with a three-dimensional structure.

[0057] Step (6) Heat treatment of building materials

[0058] S61 The prepared biomass-based building panels are placed in a heat treatment furnace for preheating treatment. The preheating temperature is 150℃ and the preheating time is 30min.

[0059] S62 continues to heat the preheated board to a heat treatment temperature of 200℃ at a heating rate of 5℃ / min.

[0060] After reaching the heat treatment temperature, S63 is held for 30 minutes for heat preservation treatment;

[0061] S64 slowly cools the insulated panels to obtain heat-insulating biomass-based building panels.

[0062] Example 2

[0063] Step (1) Mixing and dispersing biomass raw materials

[0064] S11 Take 250g of wood powder and crush it. After processing, dry the wood powder at 65℃. Take the dried wood powder and sieve it to obtain 70-mesh biomass pellets.

[0065] S12 mixes the biomass pellets with 800 mL of water and stirs them thoroughly with a stirrer to ensure that the biomass pellets are fully dispersed in the water;

[0066] Step (2) Preparation of surfactant

[0067] S21 Add 1.3g of fatty alcohol and 11mL of sulfuric acid to the reaction vessel and stir until homogeneous; then heat to 105℃ and carry out esterification reaction until the alcohol conversion rate reaches more than 95%;

[0068] S22 adds the esterification product to the polymerization reactor, then adds 0.6g of potassium hydroxide catalyst, and heats to 150℃ to carry out the polymerization reaction for 2.5h.

[0069] After S23 polymerization is complete, the polymerization product is added to a neutralization vessel, and excess sulfuric acid is neutralized with potassium hydroxide. The temperature is maintained at 93℃, and neutralization is carried out for 1.3 hours to make the product neutral.

[0070] S24 bleachs the neutralized product to remove colored substances, then refines it by filtration and distillation to remove impurities and oligomers, thus obtaining the surfactant fatty alcohol polyoxyethylene ether.

[0071] Step (3) Fiber dissociation of biomass raw materials

[0072] S31 In a mixture of biomass pellets and water, 6g of potassium hydroxide solution was gradually added to adjust the pH of the mixture to 8, and the mixture was stirred continuously for 1.3h.

[0073] Add 0.2g of surfactant fatty alcohol polyoxyethylene ether to S32 and stir continuously for 1.3h to allow the biomass fiber to gradually dissociate into smaller fiber units under the combined action of potassium hydroxide alkaline substance and surfactant.

[0074] Step (4) Hydrogen bond recombination of biomass feedstock

[0075] After the fiber dissociation is complete, 0.4g of polyvinylpyrrolidone is added, and the mixture is stirred for 2.5h to allow the dissociated fiber units to recombine through interactions such as hydrogen bonds to form a more compact network structure.

[0076] Step (5) Sheet pressing

[0077] The recombined mixture is poured into a mold, a pressure of 20 MPa is applied, and then dried at 110°C for 8 hours. During this process, the moisture in the mixture gradually evaporates, and the fiber units are further arranged in a tighter manner to obtain a biomass-based building board with a three-dimensional structure.

[0078] Step (6) Heat treatment of building materials

[0079] S61 The prepared biomass-based building panels are placed in a heat treatment furnace for preheating treatment. The preheating temperature is 160℃ and the preheating time is 40min.

[0080] S62 continues to heat the preheated board to a heat treatment temperature of 230°C at a heating rate of 6°C / min.

[0081] After reaching the heat treatment temperature, S63 is held for 40 minutes for heat preservation treatment;

[0082] S64 slowly cools the insulated panels to obtain heat-insulating biomass-based building panels.

[0083] Example 3

[0084] Step (1) Mixing and dispersing biomass raw materials

[0085] S11 Take 300g of wood powder and crush it. After processing, dry the wood powder at 70℃. Take the dried wood powder and sieve it to obtain 80-mesh biomass pellets.

[0086] S12 mixes the biomass pellets with 1300 mL of water and stirs them thoroughly with a stirrer to ensure that the biomass pellets are fully dispersed in the water;

[0087] Step (2) Preparation of surfactant

[0088] S21 Add 1.6g of fatty alcohol and 13mL of sulfuric acid to the reaction vessel and stir until homogeneous; then heat to 110℃ and carry out esterification reaction until the alcohol conversion rate reaches more than 95%;

[0089] S22 adds the esterification product to the polymerization reactor, then adds 0.4g of potassium hydroxide catalyst, and heats to 160℃ to carry out the polymerization reaction for 3 hours;

[0090] After S23 polymerization is complete, the polymerization product is added to a neutralization vessel, and excess sulfuric acid is neutralized with potassium hydroxide. The temperature is maintained at 96℃, and neutralization is carried out for 1.6 hours to make the product neutral.

[0091] S24 bleachs the neutralized product to remove colored substances, then refines it by filtration and distillation to remove impurities and oligomers, thus obtaining the surfactant fatty alcohol polyoxyethylene ether.

[0092] Step (3) Fiber dissociation of biomass raw materials

[0093] S31 In a mixture of biomass pellets and water, 7g of potassium hydroxide solution was gradually added to adjust the pH of the mixture to 9, and the mixture was stirred continuously for 1.6h.

[0094] Add 0.3g of surfactant fatty alcohol polyoxyethylene ether to S32 and stir continuously for 1.6h to allow the biomass fiber to gradually dissociate into smaller fiber units under the combined action of potassium hydroxide alkaline substance and surfactant.

[0095] Step (4) Hydrogen bond recombination of biomass feedstock

[0096] After the fiber dissociation is complete, 0.6g of polyvinylpyrrolidone is added, and the mixture is stirred for 3 hours to allow the dissociated fiber units to recombine through interactions such as hydrogen bonds, forming a more compact network structure.

[0097] Step (5) Sheet pressing

[0098] The recombined mixture is poured into a mold, a pressure of 40 MPa is applied, and then it is dried at 120°C for 10 hours. During this process, the moisture in the mixture gradually evaporates, and the fiber units are further arranged in a tighter manner to obtain a biomass-based building board with a three-dimensional structure.

[0099] Step (6) Heat treatment of building materials

[0100] S61 The prepared biomass-based building panels are placed in a heat treatment furnace for preheating treatment. The preheating temperature is 180℃ and the preheating time is 50min.

[0101] S62 continues to heat the preheated board to a heat treatment temperature of 260°C at a heating rate of 8°C / min.

[0102] After reaching the heat treatment temperature, S63 is held for 50 minutes for heat preservation treatment.

[0103] S64 slowly cools the insulated panels to obtain heat-insulating biomass-based building panels.

[0104] Example 4

[0105] Step (1) Mixing and dispersing biomass raw materials

[0106] S11 Take 350g of wood powder and crush it. After processing, dry the wood powder at 75℃. Take the dried wood powder and sieve it to obtain 100-mesh biomass pellets.

[0107] S12 mixes the biomass pellets with 1500mL of water and stirs them thoroughly with a stirrer to ensure that the biomass pellets are fully dispersed in the water;

[0108] Step (2) Preparation of surfactant

[0109] S21 Add 2g of fatty alcohol and 15mL of sulfuric acid to the reaction vessel and stir until homogeneous; then heat to 120℃ and carry out esterification reaction until the alcohol conversion rate reaches more than 95%;

[0110] S22 adds the esterification product to the polymerization reactor, then adds 0.8g of potassium hydroxide catalyst, and heats to 180℃ to carry out the polymerization reaction for 4 hours;

[0111] After S23 polymerization is complete, the polymerization product is added to a neutralization vessel, and excess sulfuric acid is neutralized with potassium hydroxide. The temperature is maintained at 100℃, and neutralization is carried out for 2 hours to make the product neutral.

[0112] S24 bleachs the neutralized product to remove colored substances, then refines it by filtration and distillation to remove impurities and oligomers, thus obtaining the surfactant fatty alcohol polyoxyethylene ether.

[0113] Step (3) Fiber dissociation of biomass raw materials

[0114] S31 In a mixture of biomass pellets and water, 8g of potassium hydroxide solution was gradually added to adjust the pH of the mixture to 10, and the mixture was stirred continuously for 2 hours.

[0115] Add 0.4g of surfactant fatty alcohol polyoxyethylene ether to S32 and stir continuously for 2 hours to allow the biomass fiber to gradually dissociate into smaller fiber units under the combined action of potassium hydroxide alkaline substance and surfactant.

[0116] Step (4) Hydrogen bond recombination of biomass feedstock

[0117] After the fiber dissociation is complete, 0.8g of polyvinylpyrrolidone is added, and the mixture is stirred for 4 hours to allow the dissociated fiber units to recombine through interactions such as hydrogen bonds, forming a more compact network structure.

[0118] Step (5) Sheet pressing

[0119] The recombined mixture is poured into a mold, a pressure of 60 MPa is applied, and then it is dried at 140°C for 12 hours. During this process, the moisture in the mixture gradually evaporates, and the fiber units are further arranged in a tighter manner to obtain a biomass-based building board with a three-dimensional structure.

[0120] Step (6) Heat treatment of building materials

[0121] S61 The prepared biomass-based building panels are placed in a heat treatment furnace for preheating treatment. The preheating temperature is 200℃ and the preheating time is 60min.

[0122] S62 continues to heat the preheated board to a heat treatment temperature of 300℃ at a heating rate of 10℃ / min.

[0123] After reaching the heat treatment temperature, S63 is held for 60 minutes for heat preservation treatment;

[0124] S64 slowly cools the insulated panels to obtain heat-insulating biomass-based building panels.

[0125] Comparative Example 1

[0126] Step (1) Mixing and dispersing biomass raw materials

[0127] S11 Take 200g of wood powder and crush it. After processing, dry the wood powder at 60℃. Take the dried wood powder and sieve it to obtain 60-mesh biomass pellets.

[0128] S12 mixes the biomass pellets with 500 mL of water and stirs them thoroughly with a stirrer to ensure that the biomass pellets are fully dispersed in the water;

[0129] Step (2) Fiber dissociation of biomass raw materials

[0130] In a mixture of biomass pellets and water, 5g of potassium hydroxide solution was gradually added to adjust the pH of the mixture to 8. The mixture was stirred continuously for 1 hour, so that the biomass fibers would gradually dissociate into smaller fiber units under the action of the alkaline potassium hydroxide.

[0131] Step (3) Hydrogen bond recombination of biomass feedstock

[0132] After the fiber dissociation is complete, continue stirring the mixture for 2 hours to allow the dissociated fiber units to recombine through interactions such as hydrogen bonds, forming a more compact network structure.

[0133] Step (4) Sheet pressing

[0134] The recombined mixture is poured into a mold, a pressure of 10 MPa is applied, and then dried at 100°C for 6 hours. During this process, the moisture in the mixture gradually evaporates, and the fiber units are further arranged in a tighter manner to obtain a biomass-based building board with a three-dimensional structure.

[0135] Step (5) Heat treatment of building materials

[0136] S51 The prepared biomass-based building panels are placed in a heat treatment furnace for preheating treatment. The preheating temperature is 150℃ and the preheating time is 30min.

[0137] S52 continues to heat the preheated board to a heat treatment temperature of 200℃ at a heating rate of 5℃ / min.

[0138] After reaching the heat treatment temperature, S53 is held for 30 minutes for heat preservation treatment;

[0139] S54 slowly cools the insulated panels to obtain heat-insulating biomass-based building panels.

[0140] Comparative Example 2

[0141] Step (1) Mixing and dispersing biomass raw materials

[0142] S11 Take 350g of wood powder and crush it. After processing, dry the wood powder at 75℃. Take the dried wood powder and sieve it to obtain 100-mesh biomass pellets.

[0143] S12 mixes the biomass pellets with 1500mL of water and stirs them thoroughly with a stirrer to ensure that the biomass pellets are fully dispersed in the water;

[0144] Step (2) Fiber dissociation of biomass raw materials

[0145] In a mixture of biomass pellets and water, 8g of potassium hydroxide solution was gradually added to adjust the pH of the mixture to 10. The mixture was stirred continuously for 2 hours to allow the biomass fibers to gradually dissociate into smaller fiber units under the action of the alkaline potassium hydroxide.

[0146] Step (3) Hydrogen bond recombination of biomass feedstock

[0147] After the fiber dissociation is complete, the mixture is stirred for another 4 hours to allow the dissociated fiber units to recombine through interactions such as hydrogen bonds, forming a more compact network structure.

[0148] Step (4) Sheet pressing

[0149] The recombined mixture is poured into a mold, a pressure of 60 MPa is applied, and then it is dried at 140°C for 12 hours. During this process, the moisture in the mixture gradually evaporates, and the fiber units are further arranged in a tighter manner to obtain a biomass-based building board with a three-dimensional structure.

[0150] Step (5) Heat treatment of building materials

[0151] S51 The prepared biomass-based building panels are placed in a heat treatment furnace for preheating treatment. The preheating temperature is 200℃ and the preheating time is 60min.

[0152] S52 continues to heat the preheated board to a heat treatment temperature of 300℃ at a heating rate of 10℃ / min.

[0153] After reaching the heat treatment temperature, S53 is held for 60 minutes for heat preservation treatment.

[0154] S54 slowly cools the insulated panels to obtain heat-insulating biomass-based building panels.

[0155] The heat-insulating biomass-based building panels obtained in Examples 1 to 4 and the products in Comparative Examples 1 and 2 were tested using the following specific testing methods:

[0156] Thermal insulation performance testing

[0157] Using a DR-FR3030-A thermal conductivity meter, the thermal conductivity of the heat-insulating biomass-based building panels prepared in the examples and comparative examples was measured in the thermal conductivity meter according to the standard method.

[0158] Tensile strength test

[0159] The tensile strength of the thermally insulating biomass-based building panels prepared in the examples and comparative examples was determined using an HT-101SC tensile testing machine. Multiple measurements were taken and the average value was recorded.

[0160] Table 1. Test results of thermal insulation performance

[0161] Example Thermal conductivity (W / (m·K)) 1 0.15 2 0.13 3 0.11 4 0.06 Comparative Example 1 0.34 Comparative Example 2 0.29

[0162] Table 1 shows that the thermal conductivity of the heat-insulating biomass-based building panels prepared in Examples 1-4 is lower than that of the heat-insulating biomass-based building panels prepared in Comparative Examples 1 and 2, demonstrating better thermal insulation performance. In these examples, the surfactant fatty alcohol polyoxyethylene ether was added, which can effectively reduce the interfacial tension between biomass raw materials, promoting uniform dispersion of the raw materials and allowing them to be mixed more evenly. This avoids the problem of excessively high or low local concentrations, improves the mixing efficiency of the raw materials, and enhances the interaction force between them. It can form bonds with hydrophilic groups in the raw materials through hydrogen bonding and other interactions, thereby improving the overall stability of the raw materials. This bonding effect helps to form a denser board structure during subsequent molding and pressing processes, improving the mechanical properties and thermal insulation performance of the board.

[0163] Table 2 Tensile strength test results

[0164] Example Tensile strength (MPa) 1 1.65 2 1.78 3 1.98 4 2.24 Comparative Example 1 0.75 Comparative Example 2 0.86

[0165] Table 1 shows that the tensile strength of the thermally insulated biomass-based building panels prepared in Examples 1-4 is lower than that of the thermally insulated biomass-based building panels prepared in Comparative Examples 1 and 2, demonstrating better resistance to damage under load. In these examples, the surfactant fatty alcohol polyoxyethylene ether was creatively added during the preparation of the thermally insulated biomass-based building panels, improving the fiber dissociation effect. Furthermore, polyvinylpyrrolidone (PVP) was added during hydrogen bond recombination, as it possesses multiple polar groups that can bind to the hydroxyl groups on the fiber surface. These groups can tightly bind to the fiber surface, promoting hydrogen bond formation and accelerating the hydrogen bond recombination process. PPVP, by binding to the hydroxyl groups on the fiber surface, can form a stable complex. This complex enhances the stability of the fibers, improving the quality and tensile strength of the panels.

[0166] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A preparation process for a heat-insulating biomass-based building panel, characterized in that... include: Step (1) Mixing and dispersing biomass raw materials S11 Take an appropriate amount of wood powder and crush it. After processing, dry the wood powder under certain conditions. Take the dried wood powder and sieve it to obtain biomass pellets of a certain particle size. S12 mixes biomass pellets with an appropriate amount of water and uses a stirrer to stir thoroughly, so that the biomass pellets are fully dispersed in the water. Step (2) Preparation of surfactant S21 Add 1~2g of fatty alcohol and 10~15mL of sulfuric acid to the reaction vessel and stir until homogeneous; then raise the temperature to 100~120℃ and carry out the esterification reaction until the alcohol conversion rate reaches more than 95%; S22 The esterification product is added to the polymerization reactor, and then 0.2~0.8g of potassium hydroxide catalyst is added. At the same time, the mixture is heated to 140~180℃ to carry out the polymerization reaction for 2~4h. After S23 polymerization is complete, the polymerization product is added to a neutralization vessel, and excess sulfuric acid is neutralized with potassium hydroxide. The temperature is maintained at 90~100℃, and neutralization is carried out for 1~2 hours to make the product neutral. S24 bleachs the neutralized product to remove colored substances, then refines it by filtration and distillation to remove impurities and oligomers, thus obtaining the surfactant fatty alcohol polyoxyethylene ether. Step (3) Fiber dissociation of biomass raw materials S31 In a mixture of biomass pellets and water, gradually add 5-8g of potassium hydroxide solution to adjust the pH of the mixture to 8-10 and stir continuously for 1-2 hours. Add 0.1~0.4g of surfactant fatty alcohol polyoxyethylene ether to S32 and stir continuously for 1~2 hours to allow the biomass fiber to gradually dissociate into smaller fiber units under the combined action of potassium hydroxide alkaline substance and surfactant. Step (4) Hydrogen bond recombination of biomass feedstock After the fiber dissociation is complete, add 0.2~0.8g of polyvinylpyrrolidone, and then continue to stir the mixture for 2~4h to allow the dissociated fiber units to recombine through hydrogen bonding interactions to form a more compact network structure. Step (5) Sheet pressing The recombined mixture is poured into a mold, pressure is applied, and then it is dried. During this process, the moisture in the mixture gradually evaporates, and the fiber units are further arranged in a tighter manner to form a biomass-based building panel with a three-dimensional structure. Step (6) Heat treatment of building materials S61 The prepared biomass-based building panels are placed in a heat treatment furnace for preheating treatment. The preheating temperature is 150~200℃ and the preheating time is 30~60min. S62 continues to heat the preheated board to a heat treatment temperature of 200-300℃ at a heating rate of 5-10℃ / min. After reaching the heat treatment temperature, S63 is held for 30-60 minutes for heat preservation treatment. S64 slowly cools the insulated panels to obtain heat-insulating biomass-based building panels.

2. The preparation process of a heat-insulating biomass-based building panel according to claim 1, characterized in that: Step (1) The mixing and dispersion of biomass raw materials includes the following steps: S11 Take 200~350g of wood powder and crush it. After crushing, dry the wood powder at 60~75℃. Take the dried wood powder and sieve it to obtain 60~100 mesh biomass pellets. S12 mixes the biomass pellets with 500-1500 mL of water and stirs them thoroughly with a stirrer to ensure that the biomass pellets are fully dispersed in the water.

3. The preparation process of a heat-insulating biomass-based building panel according to claim 1, characterized in that: Step (5) pressing of the board includes pouring the recombined mixture into a mold, applying a pressure of 10~60MPa, and then drying at 100~140℃ for 6~12h; during this process, the moisture in the mixture gradually evaporates and promotes the fiber units to be arranged more tightly, so as to obtain a biomass-based building board with a three-dimensional structure.

Images