Fireproof insulation board for building outer wall and preparation method of fireproof insulation board

Abstract

The invention relates to a fireproof insulation board for a building outer wall, the main raw material of the fireproof insulation board is a fireproof insulation attachment material, the raw materials of the fireproof insulation board comprise edible mycelia, the fireproof insulation attachment material and a modified biomass material are uniformly mixed to serve as a culture medium, and the culture medium is used for culturing the edible mycelia. A hypha-adhesion material-biomass mixture coated with hypha is formed between the hypha and the culture medium, and then the mixture is subjected to hot press molding to prepare the heat insulation board. According to the method, the fireproof heat-preservation attachment material and the modified biomass material are mixed to serve as a culture medium of the edible mycelia, the edible mycelia are cultured, the medium is completely coated with the edible mycelia, a mycelia-attachment material-modified biomass three-dimensional composite structure is formed between the mycelia and the culture medium, and the three-dimensional interlocking fireproof barrier is formed; the flame retardant property is excellent.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to a fireproof and heat-insulating board for building exterior walls and its preparation method. Background Technology

[0002] In fields such as construction and aerospace, fire-resistant insulation materials are crucial for ensuring safety and energy conservation. Traditional fire-resistant insulation materials, such as rock wool and polystyrene, suffer from numerous problems, including high pollution levels and difficulty in degradation. For example, the production process of rock wool consumes a large amount of energy; polystyrene is flammable and releases toxic gases such as HCN and CO during combustion, exacerbating the dangers of fires. Therefore, developing environmentally friendly and reliable new fire-resistant insulation materials has become an urgent need for the industry.

[0003] In recent years, new fireproof and heat-insulating materials made from mycelial composites have emerged. Mycelium can be grown using agricultural waste such as straw and sawdust as a culture medium, resulting in low production costs and environmental friendliness. In addition, its heat insulation performance is close to that of traditional high-quality heat insulation materials. In terms of fire resistance, the chitin and protein components contained in the mycelium can form a carbon layer when heated, which can mitigate the spread of fire to a certain extent.

[0004] However, mycelial composite materials still have shortcomings in practical applications. Particularly noteworthy is the insufficient flame-retardant performance of mycelial fireproof and heat-insulating materials. Under high-temperature environments, the organic components of the mycelium continue to decompose and burn. The carbon layer they form cannot effectively insulate heat and prevent the spread of flames for an extended period. This results in insufficient time for evacuation and rescue during a fire, posing a significant safety hazard. Summary of the Invention

[0005] The present invention aims to solve the problems existing in the prior art by providing a fireproof and heat-insulating board for building exterior walls, which has excellent flame-retardant properties.

[0006] The technical solution adopted by the present invention to solve its technical problem is as follows: a fireproof and heat-insulating board for building exterior walls, the main raw material of which is a fireproof and heat-insulating adhesive. The raw material of the fireproof and heat-insulating board includes edible mycelium. The fireproof and heat-insulating adhesive is mixed evenly with modified biomass material as a culture medium. The edible mycelium is cultured in the culture medium, so that a mycelium-adhesive-biomass mixture is formed between the mycelium and the culture medium. Then the mixture is hot-pressed to form a heat-insulating board.

[0007] This application uses a mixture of fire-resistant and heat-insulating adhesive and modified biomass material as a culture medium for edible mycelium. The edible mycelium is cultivated to completely coat the substrate, forming a three-dimensional composite structure of mycelium-adhesive-modified biomass, ultimately creating a three-dimensional interlocking fire barrier. First, the mycelium attached to the surface of the culture medium undergoes high-temperature catalytic carbonization to form a carbonized layer, which isolates oxygen to achieve flame retardancy. Second, the mycelium in the mixture grows freely and penetrates into the culture medium, connecting the fire-resistant and heat-insulating adhesive and the modified biomass material. Simultaneously, as the outer layer of mycelium in the three-dimensional composite structure carbonizes, the internal structure, mixed with the fire-resistant and heat-insulating adhesive and modified biomass material, and with the oxygen-barrier and flame-retardant carbonized layer on the outer layer, gradually and slowly carbonizes the mycelium within the three-dimensional composite structure. This allows the insulation board to insulate heat for a long time and prevent the spread of flames.

[0008] Preferably, the edible mycelium is a three-dimensional network structure formed by solid-state fermentation of oyster mushroom strain, with mycelium length of 5-8 μm and density >20 km / m². 3 On the one hand, the three-dimensional network structure formed by oyster mushroom mycelium has a high density, which can slow down heat conduction and thus extend the fire resistance time of the material; on the other hand, oyster mushroom mycelium is rich in polysaccharides, which can form a stable carbonized layer during combustion, thus isolating oxygen.

[0009] Preferably, the fireproof and heat-insulating adhesive includes expanded perlite and nano vermiculite flakes, and the composition of the heat-insulating board is 15-20 wt% edible mycelium, 50-60 wt% expanded perlite, 5-10 wt% nano vermiculite flakes, and 20-25 wt% biomass material.

[0010] Preferably, the expanded perlite is composed of composite particles with a particle size of 0.5-3 mm. Using expanded perlite composed of 0.5-3 mm particles increases the bulk density and reduces the porosity between materials.

[0011] Preferably, the biomass material is one or more of sawdust or bamboo shavings. Both sawdust and bamboo shavings have a high fiber content, and the use of natural fibers in conjunction with perlite can form a composite structure that combines rigidity and flexibility, reducing the brittleness of the insulation material.

[0012] A method for preparing a fireproof and heat-insulating board for building exterior walls includes the following steps: S1. Raw material pretreatment: First, the biomass material is impregnated with a flame retardant for modification, and then ultrasonically treated at 60℃ for 2 hours to obtain flame-retardant modified biomass material. Then, the fireproof and heat-insulating adhesive is surface-modified with a silane coupling agent for hydrophobic modification. Finally, the flame-retardant modified biomass material and the fireproof and heat-insulating adhesive with the surface-modified with a silane coupling agent are mixed to form a culture medium and sterilized. Additives are added before mycelial culture, and no other additives are added to the culture medium after the mycelium has been cultured. This ensures the integrity of the subsequent mycelium and prevents mycelial breakage.

[0013] S2. Mycelial bioassembly: Edible mycelia are inoculated into the sterilized culture medium and then cultured at a constant temperature until the mycelia completely cover the substrate. S3. Hot Press Molding: The substrate completely covered by mycelium is first molded, and then heat-treated to terminate mycelial growth and solidify the structure, resulting in a fireproof and heat-insulating board. In this embodiment, the fireproof and heat-insulating board is directly molded using mycelial growth and template curing without the addition of other curing additives, ensuring the fireproof performance of the board. Furthermore, no other operations are performed on the cultured mycelium before molding, ensuring the integrity of the mycelium, preventing mycelial breakage, and thus avoiding pores in the board, guaranteeing the heat-insulating effect of the board after molding.

[0014] Preferably, the flame retardant in step S1 is one or more of ammonium phosphate or zinc borate. Using ammonium phosphate or zinc borate as common inorganic flame retardants has two advantages: firstly, both can generate moisture at high temperatures and form a covering layer to reduce heat and isolate oxygen; secondly, ammonium phosphate and zinc borate can work synergistically to achieve flame retardancy while reducing mechanical strength loss, maintaining the toughness of biomass materials, and preserving the compressive strength of the insulation board.

[0015] Preferably, the silane coupling agent in step S1 is KH550. Using KH550 to hydrophobically modify expanded perlite utilizes its surface modification and interface enhancement functions. By forming a dense organosilicon layer and optimizing the material interface, water penetration can be effectively reduced.

[0016] Preferably, in order to ensure the smooth growth of edible fungi mycelium, the cultivation conditions for edible fungi in step S2 are constant temperature cultivation at 28°C for 7 days, humidity controlled at 85±3%, and CO2 concentration <2000ppm.

[0017] Preferably, the molding conditions in step S3 are 0.8 MPa and the heat treatment conditions are 120°C.

[0018] The beneficial effects of this invention are: 1. This invention uses a mixture of fireproof and heat-insulating adhesive and modified biomass material as a culture medium for edible mycelium. The edible mycelium is cultured to completely cover the substrate, forming a three-dimensional composite structure of mycelium-adhesive-modified biomass between the mycelium and the culture medium, which ultimately constitutes a three-dimensional interlocking fire barrier.

[0019] 2. This invention uses oyster mushroom mycelium as raw material, adding modified sawdust or modified bamboo shavings to expanded perlite and nano-vermiculite. This allows the oyster mushroom mycelium to grow and penetrate the pores of the expanded perlite and wrap around the modified sawdust or modified bamboo shavings, forming a three-dimensional interlocking network. This achieves physical isolation, catalytic carbonization, and chemical flame retardancy. When the expanded perlite is heated, it forms a closed structure with a honeycomb foam-like structure, blocking heat convection. The carbonized layer of mycelium forms continuous graphene sheets at high temperatures, thus achieving flame retardancy. When the material is heated, the flame retardant on the modified sawdust or modified bamboo shavings inhibits combustion through dehydration carbonization and the release of non-combustible gases.

[0020] 3. This invention uses expanded perlite and nano vermiculite flakes as a skeleton, and adds sawdust or bamboo shavings as flexible connections between the skeletons. By utilizing the properties of the fibers of sawdust or bamboo shavings, the brittleness of expanded perlite and nano vermiculite flakes is reduced. When the material is impacted, the sliding and deformation between the fibers can absorb energy, avoid stress concentration leading to cracking, and improve the impact resistance of the fireproof and heat-insulating material.

[0021] 4. The organic acids produced by the mycelium during the metabolism of the mycelium in this invention can be used to repair the micro-cracks between the culture medium and the mycelium, thereby further improving the heat preservation effect. Detailed Implementation

[0022] To further illustrate the technical means and effects of the present invention in achieving the intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention, in conjunction with preferred embodiments, is provided below.

[0023] Example 1 Fireproof and thermal insulation material for building exterior walls, by weight ratio: 20wt% oyster mushroom mycelium, 55wt% expanded perlite (composite of expanded perlite with a particle size of 0.5-3mm), 5wt% nano vermiculite flakes, and 20wt% sawdust.

[0024] The above raw materials are prepared according to the following steps: S1. Raw material pretreatment: First, the sawdust is soaked in a 10% solution of ammonium phosphate and zinc borate for modification to obtain flame-retardant modified sawdust. Then, KH550 is used to hydrophobically modify the expanded perlite. Finally, the hydrophobically modified expanded perlite, flame-retardant modified sawdust and nano vermiculite sheets are mixed as a culture medium and sterilized. S2. Mycelial bioassembly: The sterilized culture medium is inoculated with the oyster mushroom strain formed by solid-state fermentation, and then cultured at a constant temperature of 28℃ for 7 days, with humidity controlled at 85±3% and CO2 concentration <2000ppm, until the mycelium completely covers the substrate. S3. Hot pressing molding: The substrate completely covered by mycelium is first molded under a pressure of 0.8MPa, and then heat-treated at 120℃ to terminate mycelial growth and solidify the structure to obtain a fireproof and heat-insulating board.

[0025] The sample of Example 1 was tested according to the method of standard GB / T 10294, and the result of thermal conductivity was ≤0.05.

[0026] The sample of Example 1 was tested according to the method of standard GB / T 2406, and the LOI value was ≥55%.

[0027] Example 2 The fireproof and thermal insulation material for building exterior walls, by weight ratio, is: 20wt% oyster mushroom mycelium, 55wt% expanded perlite (composite of expanded perlite with a particle size of 0.5-3mm), 8wt% nano vermiculite flakes, and 17wt% bamboo chips.

[0028] The above raw materials are prepared according to the following steps: S1. Raw material pretreatment: First, bamboo chips are soaked in a 10% solution of ammonium phosphate and zinc borate for modification to obtain flame-retardant modified bamboo chips. Then, KH550 is used to hydrophobically modify expanded perlite. Finally, the hydrophobically modified expanded perlite, flame-retardant modified bamboo chips and nano vermiculite sheets are mixed as a culture medium and sterilized. S2. Mycelial bioassembly: The sterilized culture medium is inoculated with the oyster mushroom strain formed by solid-state fermentation, and then cultured at a constant temperature of 28℃ for 7 days, with humidity controlled at 85±3% and CO2 concentration <2000ppm, until the mycelium completely covers the substrate. S3. Hot pressing molding: The substrate completely covered by mycelium is first molded under a pressure of 0.8MPa, and then heat-treated at 120℃ to terminate mycelial growth and solidify the structure to obtain a fireproof and heat-insulating board.

[0029] The sample of Example 2 was tested according to the method of standard GB / T 10294, and the result of thermal conductivity was ≤0.048.

[0030] The sample of Example 2 was tested according to the method of standard GB / T 2406, and the LOI value was ≥60%.

[0031] Example 3 Fireproof and heat-insulating materials for building exterior walls, by weight ratio: 20wt% oyster mushroom mycelium, 60wt% expanded perlite (composite of expanded perlite with a particle size of 0.5-3mm), 8wt% nano vermiculite flakes, 2wt% sawdust, and 10wt% bamboo shavings.

[0032] The above raw materials are prepared according to the following steps: S1. Raw material pretreatment: First, sawdust and bamboo shavings are soaked in a 10% solution of ammonium phosphate and zinc borate for modification to obtain flame-retardant modified sawdust and flame-retardant modified bamboo shavings. Then, KH550 is used to hydrophobically modify expanded perlite. Finally, the hydrophobically modified expanded perlite, flame-retardant modified sawdust, flame-retardant modified bamboo shavings and nano vermiculite sheets are mixed as a culture medium and sterilized. S2. Mycelial bioassembly: The sterilized culture medium is inoculated with the oyster mushroom strain formed by solid-state fermentation, and then cultured at a constant temperature of 28℃ for 7 days, with humidity controlled at 85±3% and CO2 concentration <2000ppm, until the mycelium completely covers the substrate. S3. Hot pressing molding: The substrate completely covered by mycelium is first molded under a pressure of 0.8MPa, and then heat-treated at 120℃ to terminate mycelial growth and solidify the structure to obtain a fireproof and heat-insulating board.

[0033] The sample of Example 3 was tested according to the method of standard GB / T 10294, and the result of thermal conductivity was ≤0.048.

[0034] The sample of Example 3 was tested according to the method of standard GB / T 2406, and the LOI value was ≥58%.

[0035] The raw material formula is shown in Table 1: Table 1 raw material one two three Expanded perlite 55wt% 55wt% 60wt% Nano vermiculite 5wt% 8wt% 8wt% Oyster mushroom mycelium 20wt% 20wt% 20wt% sawdust 20wt% - 2wt% Bamboo chips - 17wt% 10wt% The performance test results of Examples 1-3 are shown in Table 2: Table 2 performance one two three Remark thermal conductivity ≤0.05 ≤0.048 ≤0.048 <![CDATA[Ensure that its thickness is more than 6 cm and the dry density is 38 kg / m 3 > LOI value ≥55% ≥60% ≥58% In summary, the product of this invention has a low thermal conductivity and excellent heat preservation effect; in addition, the product of this invention has a high LOI value and strong flame retardant properties.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A fireproof and heat-insulating board for building exterior walls, the main raw material of which is a fireproof and heat-insulating adhesive, characterized in that, The raw materials of this fireproof and heat-insulating board include edible mycelium. The fireproof and heat-insulating adhesive is mixed evenly with modified biomass material as a culture medium. The edible mycelium is cultivated in this culture medium, so that a mycelium-adhesive-biomass mixture is formed between the mycelium and the culture medium. The mixture is then hot-pressed to form the heat-insulating board.

2. The fireproof and heat-insulating board for building exterior walls according to claim 1, characterized in that, The edible mycelium is a three-dimensional network structure formed by solid-state fermentation of oyster mushroom strains, with mycelium length of 5-8 μm and density >20 km / m². 3 .

3. The fireproof and heat-insulating board for exterior building walls according to claim 1, characterized in that, The fireproof and heat-insulating adhesive includes expanded perlite and nano vermiculite flakes. The components of the heat-insulating board are 15-20 wt% edible mycelium, 50-60 wt% expanded perlite, 5-10 wt% nano vermiculite flakes, and 20-25 wt% biomass material.

4. The fireproof and heat-insulating board for building exterior walls according to claim 3, characterized in that, The expanded perlite is composed of particles ranging from 0.5 to 3 mm in size.

5. The fireproof and heat-insulating board for building exterior walls according to claim 1 or 3, characterized in that, The biomass material is one or more of sawdust or bamboo shavings.

6. The method for preparing the fireproof and heat-insulating board for building exterior walls according to claim 1, characterized in that, Includes the following steps: S1. Raw material pretreatment: First, the biomass material is impregnated with flame retardant for modification treatment, and then ultrasonically treated at 60℃ for 2 hours to obtain flame-retardant modified biomass material. Then, the fireproof and heat-insulating adhesive is modified with a silane coupling agent to make its surface hydrophobic. Finally, the flame-retardant modified biomass material and the fireproof and heat-insulating adhesive modified with a silane coupling agent to make a culture medium are mixed and sterilized. S2. Mycelial bioassembly: Edible mycelia are inoculated into the sterilized culture medium and then cultured at a constant temperature until the mycelia completely cover the substrate. S3. Hot pressing molding: The matrix completely covered by mycelium is first molded, and then heat-treated to stop mycelial growth and solidify the structure to obtain a fireproof and heat-insulating board.

7. The method for preparing the fireproof and heat-insulating board for building exterior walls according to claim 6, characterized in that, The flame retardant in step S1 is one or more of ammonium phosphate or zinc borate.

8. The method for preparing the fireproof and heat-insulating board for building exterior walls according to claim 6, characterized in that, The silane coupling agent in step S1 is KH550.

9. The method for preparing the fireproof and heat-insulating board for building exterior walls according to claim 6, characterized in that, In step S2, the edible fungi are cultured at a constant temperature of 28°C for 7 days, with humidity controlled at 85±3% and CO2 concentration <2000ppm.

10. The method for preparing the fireproof and heat-insulating board for building exterior walls according to claim 6, characterized in that, In step S3, the molding conditions are 0.8 MPa and the heat treatment conditions are 120°C.