Aerogel composite insulation board and production process thereof

Abstract

The invention discloses an aerogel composite insulation board and a production process thereof, and belongs to the technical field of building insulation materials. The thermal insulation board comprises the following components in parts by weight: 16-20 parts of composite modified aerogel, 48-58 parts of a boron nitride reinforced base material, 13-17 parts of a polyurethane epoxy resin binder and 6-9 parts of a multifunctional additive. The composite modified aerogel is prepared by singly modifying aerogel through gamma-glycidyl ether oxypropyl trimethoxy silane, the boron nitride reinforced base material is prepared by mixing boron nitride fibers and composite porous particles, and the multifunctional additive is a combination of nano magnesium hydroxide and perfluorohexyltriethoxysilane. The thermal insulation, mechanical, hydrophobic, antibacterial and anti-aging properties are synergistically improved, the process is simplified and stable, and the thermal insulation material is suitable for industrial mass production and can be widely applied to the field of building thermal insulation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building insulation materials, in particular to an aerogel composite insulation board and a production process thereof. BACKGROUND

[0002] Aerogel has become the preferred material in the field of building insulation due to its extremely low thermal conductivity, but it still faces many technical bottlenecks in practical application. In the prior art, aerogel modification is often carried out by using multiple modifiers, which not only has a complex process and high cost, but also has poor dispersion effect due to the lack of synergy between the modifiers, and still has the problem of particle agglomeration.

[0003] For the composite substrate, the existing scheme often uses glass fiber and ordinary expanded perlite, but the mechanical strength of glass fiber is limited, and the pore structure of expanded perlite is single, which cannot meet the requirements of lightweight and high compression resistance of the insulation board at the same time, resulting in that the product is easy to be damaged during transportation or construction. The adhesive is often unmodified epoxy resin or silica sol, which has weak interfacial bonding force with aerogel and substrate, and has high brittleness after curing, and is easy to crack under the influence of temperature change for a long time, affecting the integrity and service life of the insulation board.

[0004] In addition, in the production process of the existing insulation board, the mixing of the substrate is usually simple stirring, which has poor dispersion uniformity; the drying and curing is usually carried out at a single temperature, which is easy to cause uneven evaporation of water in the blank body and form cracks; at the same time, most products lack targeted functional post-processing, and the comprehensive performance is difficult to adapt to the use requirements of complex building environment. Therefore, it is an urgent problem in the industry to develop an aerogel composite insulation board with simplified process and stable performance, which realizes high insulation and high mechanical strength by using a single modified material in combination with conventional high-quality components. SUMMARY

[0005] In view of the problems of complex modification process, insufficient mechanical properties of the substrate, poor adaptability of the adhesive, and poor process stability of the existing aerogel composite insulation board, the present application provides an aerogel composite insulation board and a production process thereof, which combines a single modified aerogel with an optimized substrate, adhesive and additive combination, simplifies the production process, and realizes the synergistic improvement of insulation performance, mechanical properties and structural stability, ensuring the process repeatability and industrial application feasibility.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme: The technical scheme provided by the present application is: An aerogel composite insulation board, comprising the following raw material components by weight: 16-20 parts of composite modified aerogel, 48-58 parts of boron nitride reinforced substrate, 13-17 parts of polyurethane epoxy resin adhesive, and 6-9 parts of multifunctional additive. The composite modified aerogel is prepared by modifying aerogel with γ-glycidoxypropyltrimethoxysilane, and the γ-glycidoxypropyltrimethoxysilane is the only modifying material; The boron nitride reinforced substrate is prepared by mixing boron nitride fibers and composite porous particles at a mass ratio of 1:1.1-1.4, the diameter of the boron nitride fibers is 10-18 μm, the length is 2.5-4.5 mm, the composite porous particles are prepared by mixing hollow aluminosilicate microbeads and expanded shale at a mass ratio of 1:1.3-1.6; The polyurethane epoxy resin adhesive is an industrial grade polyurethane modified epoxy resin; The multifunctional additive is prepared by mixing nano-magnesium hydroxide and perfluorohexyltriethoxysilane at a mass ratio of 3:1.1-1.3, the particle size of the nano-magnesium hydroxide is 45-75 nm.

[0007] Further, in the composite porous particles, the particle size of the hollow aluminosilicate microbeads is 90-160 μm, and the bulk density is 0.20-0.28 g / cm 3 The particle size of the expanded shale is 0.4-0.7 mm, and the water content is ≤0.7%.

[0008] Further, the solid content of the polyurethane epoxy resin adhesive is 68-78%.

[0009] Further, the purity of the perfluorohexyltriethoxysilane is ≥98.8%, and the specific surface area of the nano-magnesium hydroxide is 22-28 m 2 / g.

[0010] Further, in the composite modified aerogel, the addition amount of the γ-glycidoxypropyltrimethoxysilane is 8-10% of the mass of the aerogel.

[0011] A production process of an aerogel composite insulation board: The production process comprises the following steps: S1: preparing a composite modified aerogel: dispersing aerogel in ethylene glycol monomethyl ether solution, adding γ-glycidoxypropyltrimethoxysilane, stirring and reacting at 62-68 ℃ for 3.2-4.2 h, centrifugal separation after the reaction is completed, and vacuum drying at 78-88 ℃ for 3.8-4.8 h to obtain a composite modified aerogel; S2: boron nitride reinforced substrate pretreatment: low-temperature plasma surface treatment is performed on the boron nitride fibers, the treatment power is 380-480 W, the treatment time is 7-11 min, the working gas is nitrogen, and the gas flow is 18-24 L / min; hollow aluminosilicate microbeads and expanded shale are weighed according to the composite porous particle ratio, stirred at a rotating speed of 200-250 r / min for 15-20 min to obtain mixed porous particles; the pretreated boron nitride fibers are mixed with the mixed porous particles, and dried at 115-125 ℃ for 1.8-2.2 h to obtain a pretreated boron nitride reinforced substrate; S3: preparing a composite slurry: mixing the composite modified aerogel, the pretreated boron nitride reinforced substrate, the polyurethane epoxy resin binder and the multifunctional additive by weight parts, adding deionized water to adjust the slurry consistency to 95-115s, the amount of deionized water added is 11-15% of the total mass of the composite slurry, stirring at a speed of 480-530r / min for 42-48min to obtain a uniform composite slurry; S4: forming by stepwise pressing: pouring the composite slurry into a mold of a predetermined size, first pressing at 0.75-0.85MPa and 30-34℃ for 4.5-6.5min, then increasing the temperature to 48-53℃ and pressing at 0.95-1.05MPa for 5.5-7.5min to obtain a formed blank; S5: gradient drying and curing: placing the formed blank in a vacuum drying oven and drying at a temperature of 82-88℃ and a vacuum degree of -0.092 to -0.097MPa for 4.2-4.8h, the drying process adopts a stepwise heating mode, first holding at 58℃ for 1.2h, then increasing the temperature to 68℃ for 1.2h, and finally increasing the temperature to 82-88℃ for 1.8-2.4h, and then naturally cooling to room temperature for demolding to obtain a preliminary product; S6: anti-ultraviolet post-treatment: spraying a nano-silicon dioxide anti-ultraviolet coating on the surface of the preliminary product, the coating thickness is 10-15μm, the solid content of the nano-silicon dioxide anti-ultraviolet coating is 38-43%, and the mass fraction of nano-silicon dioxide is 0.4-0.6%, and then drying at 88-93℃ for 1.8-2.3h, and then cutting to a predetermined size to obtain an aerogel composite insulation board product.

[0012] Further, the amount of ethylene glycol monomethyl ether solution in S1 is 6-8 times the mass of the aerogel, and the centrifugal separation speed is 8500-9500r / min for 18-22min.

[0013] Further, in S3, the slurry consistency is tested by a Brookfield DV-4C viscometer, and the test temperature is 25-28℃.

[0014] Further, in S5, the natural cooling rate is 6-12℃ / min, and the demolding is completed when the temperature is cooled to 25-28℃.

[0015] Further, in S6, the spraying is performed by air spraying, the spraying pressure is 0.4-0.6MPa, and the spraying distance is 20-30cm.

[0016] The beneficial effects of the technical solution are: (1) Single modified aerogel as the core component, after modification treatment by gamma-glycidoxypropyltrimethoxysilane, it can effectively break the self particle agglomeration trend, form a uniform dispersion state in the system, and build a continuous and dense thermal insulation structure. At the same time, the modification treatment can optimize the interfacial compatibility of aerogel and other components, so that the aerogel and the base material, adhesive and other components are closely connected, avoiding local voids or heat conduction channels due to uneven dispersion, and fully exerting the intrinsic advantages of aerogel with extremely low thermal conductivity, laying a good thermal insulation foundation for the thermal insulation board.

[0017] (2) The composition combination of boron nitride reinforced base material forms a unique advantage. Boron nitride fiber itself has high strength characteristics and can provide stable support as the skeleton structure of the thermal insulation board. The multi-pore structure formed by the combination of hollow aluminosilicate microbeads and expanded shale, in cooperation with boron nitride fiber, not only guarantees the mechanical properties but also further optimizes the thermal insulation system. The composition characteristics of the polyurethane modified epoxy resin adhesive adapt to the interface requirements of different components, and its flexibility and strong adhesion can form a stable whole, avoiding the problem of brittleness after curing of conventional adhesives and preventing cracking or falling during use.

[0018] (3) The combination of multifunctional additives and core components forms a synergistic functional system. The combination of nano-magnesium hydroxide and perfluorohexyltriethoxysilane gives the product good water-repellent and flame-retardant properties without interfering with the thermal insulation and mechanical properties, resisting water intrusion and fire risk. Nano-silicon dioxide anti-ultraviolet coating as a functional supplementary component can form an effective protective barrier to delay the aging process of the material. The components complement each other in function and do not interfere with each other in performance, ultimately achieving synergistic improvement of multiple dimensions such as thermal insulation, mechanics, water-repellent, flame-retardant, and anti-aging. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The present application provides a preparation process schematic diagram of an aerogel composite thermal insulation board and its production process. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0021] The specific implementation process is as follows: Example 1: Please refer to Figure 1 The present application provides a technical solution: an aerogel composite thermal insulation board and its production process, including raw material ratio: Composite modified aerogel: 16 parts (γ-glycidoxypropyltrimethoxysilane addition amount is 8% of the mass of aerogel); boron nitride reinforced substrate: 58 parts (boron nitride fiber 31.6 parts, composite porous particles 26.4 parts, mass ratio 1:1.1; composite porous particles are hollow aluminosilicate microsphere 11.5 parts, expanded shale 14.9 parts, mass ratio 1:1.3; hollow aluminosilicate microsphere particle size 90 μm, bulk density 0.20 g / cm 3 , expanded shale particle size 0.4 mm, moisture content 0.6%); polyurethane epoxy resin adhesive: 13 parts (solid content 68%); multifunctional additive: 6 parts (nano-magnesium hydroxide 4.1 parts, perfluorohexyl triethoxysilane 1.9 parts, mass ratio 3:1.1; nano-magnesium hydroxide particle size 45 nm, specific surface area 22 m 2 / g, perfluorohexyl triethoxysilane purity 98.8%).

[0022] Production steps: S1: preparing composite modified aerogel: taking aerogel 14.81 kg, dispersing in 88.86 kg ethylene glycol monomethyl ether solution, adding γ-glycidoxypropyltrimethoxysilane 1.185 kg, stirring at 62 ℃ and 350 r / min for 4.2 h; after the reaction is completed, centrifugal separation is carried out at 8500 r / min for 22 min, the solid particles are collected, and vacuum drying is carried out at 78 ℃ and a vacuum degree of-0.092 MPa for 4.8 h to obtain the composite modified aerogel; S2: boron nitride reinforced substrate pretreatment: taking boron nitride fiber 31.6 kg (diameter 10 μm, length 2.5 mm), placing it in a plasma treatment device, introducing nitrogen gas (flow rate 18 L / min), and treating it at a power of 380 W for 11 min; according to the proportion, hollow aluminosilicate microsphere 11.5 kg and expanded shale 14.9 kg are weighed and stirred at a speed of 200 r / min for 20 min to obtain mixed porous particles; the pretreated boron nitride fiber and mixed porous particles are mixed and placed in a 115 ℃ air drying oven for drying for 2.2 h to obtain the pretreated boron nitride reinforced substrate; S3: preparing composite slurry: mixing each raw material according to the above weight parts, adding deionized water 13.9 kg (13% of the total mass of the composite slurry), and stirring at a speed of 480 r / min for 48 min; using a Brookfield viscometer to test at 25 ℃, the slurry consistency is 95 s, and a uniform composite slurry is obtained; S4: forming by stepwise pressing: pouring the composite slurry into a 300 mm×300 mm×50 mm steel mold, first pressing at 0.75 MPa and 30 ℃ for 6.5 min, then increasing the temperature to 48 ℃ and pressing to 0.95 MPa for 7.5 min, and demolding to obtain a formed body; S5: Gradient drying and curing: Place the shaped blank in a vacuum drying oven, and perform stepwise temperature drying: 58℃ for 1.2h, 68℃ for 1.2h, and 82℃ for 2.4h, with a vacuum degree of-0.092MPa throughout the process; after drying, reduce the temperature to 25℃ at a rate of 6℃ / min, to obtain a preliminary product; S6: Anti-ultraviolet post-treatment: spray a nano-silicon dioxide anti-ultraviolet coating (solid content 38%, nano-silicon dioxide mass fraction 0.4%) on the surface of the preliminary product by air spraying, with a spraying pressure of 0.4MPa and a distance of 20cm, and control the coating thickness to be 10μm; after spraying, place the product in a 88℃ air-drying oven for 2.3h, and cut it to a preset size, to obtain an aerogel composite insulation board product.

[0023] Test item Test result Thermal conductivity (W / (m-K)) 0.028 Compressive strength (MPa) 1.35 Hydrophobic rate (%) 98.5 Density (kg / m 3 )]]> 195 As the basic proportion of the present scheme, even if the lowest amount of composite modified aerogel and multifunctional additives are used, a low thermal conductivity of 0.028W / (m·K) is still achieved, which is far superior to the general level of 0.035W / (m·K) or above in the prior art; the compressive strength reaches 1.35MPa, meeting the core requirement of mechanical strength for building exterior wall construction; the hydrophobic rate is 98.5%, reflecting the synergistic effect of multifunctional additives; the anti-ultraviolet aging rate is 95.8%, proving the effectiveness of the anti-ultraviolet post-treatment; and the density is 195kg / m 3 The lightweight advantage is maintained, and the basic feasibility of single modified aerogel combined with optimized components and process is verified, breaking the contradiction in the prior art that low thermal conductivity must sacrifice mechanical properties.

[0024] Example 2: Please refer to Figure 1 The present application provides a technical scheme: an aerogel composite insulation board and a production process thereof, which comprises raw material proportioning: Composite modified aerogel: 18parts (γ-glycidoxypropyltrimethoxysilane addition amount is 9% of the mass of the aerogel); boron nitride reinforced substrate: 53parts (boron nitride fiber 27.9parts, composite porous particles 25.1parts, mass ratio 1:1.27; composite porous particles are hollow aluminosilicate microspheres 10.9parts and expanded shale 14.2parts, mass ratio 1:1.3; hollow aluminosilicate microspheres have a particle size of 120μm and a bulk density of 0.24g / cm 3 ; expanded shale has a particle size of 0.5mm and a moisture content of 0.5%); polyurethane epoxy resin adhesive: 15parts (solid content 73%); multifunctional additives: 7.5parts (nano-magnesium hydroxide 5.1parts, perfluorohexyltriethoxysilane 2.4parts, mass ratio 3:1.2; nano-magnesium hydroxide has a particle size of 60nm and a specific surface area of 25m 2 / g; perfluorohexyltriethoxysilane has a purity of 99.0%).

[0025] Production steps: S1: preparation of composite modified aerogel: take aerogel 16.51 kg, disperse in 115.57 kg ethylene glycol monomethyl ether solution, add 1.486 kg of γ-glycidyl ether propyltrimethoxysilane, stir at 380 r / min at 65℃ for 3.7 h; after centrifugal separation at 9000 r / min for 20 min, vacuum drying at 83℃, vacuum degree-0.095 MPa for 4.3 h, to obtain composite modified aerogel; S2: boron nitride reinforced substrate pretreatment: take boron nitride fiber 27.9 kg (diameter 14 μm, length 3.5 mm), plasma treatment (nitrogen flow 21 L / min, power 430 W, time 9 min); mix hollow aluminum silicate microbeads and expanded shale according to the ratio, stir at 220 r / min for 18 min to obtain mixed porous particles; after mixing with boron nitride fiber, dry at 120℃ for 2.0 h to obtain pretreated boron nitride reinforced substrate; S3: preparation of composite slurry: mix each raw material, add 15.22 kg of deionized water (14% of the total mass of the composite slurry), stir at 500 r / min for 45 min, test the consistency at 26℃ for 105 s to obtain the composite slurry; S4: segmented pressure forming: pour into the same size mold, first at 0.8 MPa, 32℃ for 5.5 min, then increase the temperature to 50℃, press to 1.0 MPa for 6.5 min, demold to get the formed body; S5: gradient drying and curing: stepwise temperature rising drying: 58℃ for 1.2 h, 68℃ for 1.2 h, 85℃ for 2.1 h, the whole process vacuum degree-0.095 MPa; cooling to 26℃ at a rate of 9℃ / min to obtain the initial product; S6: anti-ultraviolet post-treatment: air spraying of nano-silicon dioxide anti-ultraviolet coating (solid content 40%, nano-silicon dioxide mass fraction 0.5%), spraying pressure 0.5 MPa, distance 25 cm, coating thickness 12 μm; 90℃ drying for 2.0 h, cutting to get the finished product.

[0026] Test item Test result Thermal conductivity (W / (m-K)) 0.026 Compressive strength (MPa) 1.52 Hydrophobic rate (%) 99.3 Ultraviolet aging resistance rate (500h, %) 97.2 Density (kg / m 3 ) 188 Example 2 is balanced and optimized ratio, and each performance achieves optimal synergistic effect. The thermal conductivity is reduced to 0.026 W / (m·K), which benefits from the uniform dispersion of single modified aerogel and the multi-level pore structure of composite porous particles; the compressive strength is as high as 1.52 MPa, which is 12.6% higher than that of example 1, which confirms the interface enhancement effect of boron nitride fiber plasma pretreatment and polyurethane modified binder; the hydrophobic rate is 99.3%, and the antibacterial rate is more than 99.5%, which reflects the precise optimization of multifunctional additive ratio; the anti-ultraviolet aging rate is further improved to 97.2%, and the density is reduced to 188 kg / m 3, realizes the overall balance of low thermal conductivity, high compression resistance, high function and light weight, proves that the innovations of the scheme are not isolated, but form a synergistic technology system, which cannot be realized by single optimization of a component or process in the prior art.

[0027] Embodiment 3: Please refer to Figure 1 The application provides a kind of technical scheme: a kind of aerogel composite insulation board and its production process, including raw material ratio: Composite modified aerogel: 20 parts (γ-glycidyl ether oxygen propyl trimethoxysilane addition amount is 10% of aerogel mass);Boron nitride reinforced substrate: 48 parts (boron nitride fiber 25.3 parts, composite porous particles 22.7 parts, mass ratio 1:1.4;Composite porous particles are hollow aluminosilicate microsphere 9.5 parts, expanded shale 13.2 parts, mass ratio 1:1.6;Hollow aluminosilicate microsphere particle size 160 μm, bulk density 0.28 g / cm 3 , expanded shale particle size 0.7 mm, moisture content 0.7%);Polyurethane epoxy resin adhesive: 17 parts (solid content 78%);Multifunctional additive: 9 parts (nano magnesium hydroxide 6.2 parts, perfluoro hexyl triethoxysilane 2.8 parts, mass ratio 3:1.3;Nano magnesium hydroxide particle size 75 nm, specific surface area 28 m 2 / g, perfluoro hexyl triethoxysilane purity 99.2%).

[0028] Production steps: S1: preparation of composite modified aerogel: take aerogel 18.18 kg, disperse in 145.44 kg ethylene glycol monomethyl ether solution, add γ-glycidyl ether oxygen propyl trimethoxysilane 1.82 kg, stir at 68 ℃ under 400 r / min for 3.2 h;Centrifugal separation at 9500 r / min for 18 min, vacuum drying at 88 ℃, vacuum degree-0.097 MPa for 3.8 h, to get composite modified aerogel; S2: boron nitride reinforced substrate pretreatment: take boron nitride fiber 25.3 kg (diameter 18 μm, length 4.5 mm), plasma treatment (nitrogen flow 24 L / min, power 480 W, time 7 min);Mix hollow aluminosilicate microsphere and expanded shale according to the ratio, stir at 250 r / min for 15 min to get mixed porous particles;After mixing with boron nitride fiber, 125 ℃ drying for 1.8 h, to get pretreated boron nitride reinforced substrate; S3: preparation of composite slurry: mix raw materials, add deionized water 16.59 kg (15% of the total mass of composite slurry), stir at 530 r / min for 42 min, test the consistency at 28 ℃ to be 115 s, to get composite slurry; S4: segmental press molding: pour into the same size mold, first at 0.85 MPa, 34 DEG C, 4.5 min, then increase the temperature to 53 DEG C, 1.05 MPa, 5.5 min, demoulding to form a blank; S5: gradient drying and curing: stepwise temperature drying: 58 DEG C, 1.2 h, 68 DEG C, 1.2 h, 88 DEG C, 1.8 h, the whole process vacuum degree-0.097 MPa; at a rate of 12 DEG C / min to 28 DEG C, to get the initial product; S6: anti-ultraviolet post-processing: air spraying of nano-silicon dioxide anti-ultraviolet coating (solid content 43%, nano-silicon dioxide mass fraction 0.6%), spraying pressure 0.6 MPa, distance 30 cm, coating thickness 15 microns; 93 DEG C, 1.8 h, cutting to get the finished product.

[0029] Test item Test result Thermal conductivity (W / (m-K)) 0.024 Compressive strength (MPa) 1.46 Hydrophobic rate (%) 99.5 Ultraviolet aging resistance rate (500h, %) 98.5 Density (kg / m 3 ) 182 Example 3 uses a composite modified aerogel upper limit of the additive amount, the thermal conductivity is as low as 0.024 W / (m·K), reaching the top level of the industry, suitable for polar building, low-temperature storage tank and other scenes with extremely high thermal insulation performance requirements; the compressive strength still maintains a high level of 1.46 MPa, and does not decrease significantly due to the increase of the thermal insulation component, breaking the limitation that the existing technology must sacrifice mechanical strength for extreme thermal insulation performance; the hydrophobic rate is 99.5%, the antibacterial rate is more than 99.7%, and the extreme improvement of functional performance is realized; the anti-ultraviolet aging rate is 98.5%, indicating that the product can still maintain stable performance in long-term outdoor use; the density is 182 kg / m 3 The data proves that the single modified aerogel in the scheme can still maintain good dispersibility at a high additive amount and form stable combination with other components.

[0030] Comparative Example 1: Please refer to Figure 1 , the application provides a comparative scheme: raw material ratio: unmodified aerogel: 18 parts (not modified by γ-glycidyl ether oxypropyl trimethoxysilane); boron nitride reinforced substrate: 53 parts, the rest is the same as example 2; polyurethane epoxy resin adhesive: 15 parts, the rest is the same as example 2; multifunctional additive: 7.5 parts, the rest is the same as example 2.

[0031] Production steps: except that unmodified aerogel is directly used in S1 step, and no dispersion, reaction and drying treatment is carried out, the rest steps are consistent with example 2.

[0032] Test item Test result Thermal conductivity (W / (m-K)) 0.038 Compressive strength (MPa) 0.92 Hydrophobic rate (%) 97.2 Ultraviolet aging resistance rate (500h, %) 94.1 Density (kg / m 3 ) 208 The comparative example 1 is a modified aerogel, only the aerogel is not modified, which leads to the thermal conductivity increasing to 0.038 W / (m·K), increasing by 46.2% compared with the example 2, because the unmodified aerogel particles are seriously agglomerated, a large number of voids and heat conduction channels are formed inside; the compressive strength is only 0.92 MPa, decreasing by 39.5% compared with the example 2, and lower than the minimum standard of 1.0 MPa required by the building construction, because the agglomerated aerogel cannot form effective interface bonding with the base material and the binder, resulting in a loose overall structure; the antibacterial rate is less than 91%, decreasing by about 9 percentage points compared with the example 2, proving that the single modified aerogel not only solves the agglomeration problem, but also increases the density to 208 kg / m 3 , and the lightweight advantage is lost. This data directly proves that the single modified aerogel is the core basis for realizing low thermal conductivity, high compressive strength and high function in the present scheme, and the unmodified or multi-modifier composite modification in the prior art cannot achieve the same effect.

[0033] Comparative example 2: Please refer to Figure 1 , the present application provides a comparative scheme: raw material ratio: composite modified aerogel: 18 parts, the rest is the same as example 2; conventional base material: 53 parts (glass fiber 27.9 parts, expanded perlite 25.1 parts; glass fiber diameter 14 μm, length 3.5 mm, expanded perlite particle size 0.5 mm, water content 0.5%); polyurethane epoxy resin binder: 15 parts, the rest is the same as example 2; multifunctional additive: 7.5 parts, the rest is the same as example 2.

[0034] Production steps: except that glass fiber and expanded perlite are mixed as base material in S2 step, no plasma treatment is carried out, the rest steps are consistent with example 2.

[0035] Test item Test result Thermal conductivity (W / (m-K)) 0.035 Compressive strength (MPa) 0.76 Hydrophobic rate (%) 98.0 Ultraviolet aging resistance rate (500h, %) 95.3 Density (kg / m 3 )]]> 215 The comparative example 2 replaces the boron nitride reinforced base material and plasma pretreatment process of the present scheme, and adopts the conventional glass fiber + expanded perlite combination of the prior art, resulting in a compressive strength of only 0.76 MPa, decreasing by 50.0% compared with the example 2, which is far lower than the building use standard, because the tensile strength of glass fiber (≤500 MPa) is much lower than that of boron nitride fiber (≥3000 MPa), and the interface bonding force is weak without plasma pretreatment, which cannot form effective skeleton support; the thermal conductivity increases to 0.035 W / (m·K), increasing by 34.6% compared with the example 2, because the single pore structure of expanded perlite cannot form a multi-level insulation system with hollow aluminum silicate microsphere and expanded shale; the density increases to 215 kg / m 3 , and the lightweight effect is lost. This data proves that the boron nitride reinforced base material and plasma pretreatment process of the present scheme solve the contradiction between mechanical strength and insulation performance of the existing base material, and the technical effect cannot be achieved by the conventional base material combination.

[0036] Comparative Example 3: Please refer to Figure 1 The present application provides a comparative scheme: raw material ratio: composite modified aerogel: 18 parts, the rest is the same as example 2; Boron nitride reinforced substrate: 53 parts, the rest is the same as example 2; Conventional adhesive: 15 parts (ordinary epoxy resin, solid content 73%, not modified by polyurethane); Multifunctional additives: 7.5 parts, the rest is the same as example 2.

[0037] Production steps: except that ordinary epoxy resin is used to replace polyurethane epoxy resin adhesive in S3 step, the rest of the steps are consistent with example 2.

[0038] Test item Test result Thermal conductivity (W / (m-K)) 0.032 Compressive strength (MPa) 0.88 Hydrophobic rate (%) 91.3 (after 5 years) Ultraviolet aging resistance rate (500h, %) 93.8 Density (kg / m 3 ) 196 Comparative example 3 uses the conventional ordinary epoxy resin of prior art to replace the polyurethane modified epoxy resin adhesive of the present application, resulting in a compressive strength of 0.88 MPa, which is 42.1% lower than that of example 2. Because ordinary epoxy resin is brittle after curing, it cannot adapt to the interface characteristics of aerogel and boron nitride fiber, and microcracks are easy to produce. More importantly, the hydrophobic rate decreases to 91.3% after 5 years, which is 8.4% lower than that of example 2. Because ordinary epoxy resin has poor aging resistance, it is easy to crack during long-term use, resulting in water intrusion and damage to the hydrophobic layer. The thermal conductivity increases to 0.032 W / (m·K), which is 19.2% higher than that of example 2. Because the interface is not tightly combined, local heat conduction channels are formed. The data prove that the polyurethane modified epoxy resin adhesive of the present application solves the problems of large brittleness and poor long-term stability of existing adhesives.

[0039] Comparative Example 4: Please refer to Figure 1 The present application provides a comparative scheme: raw material ratio: exactly the same as example 2.

[0040] Production steps: except that S4 step uses single press forming (directly at 1.0 MPa, 50℃ for 12 min), the rest of the steps are consistent with example 2.

[0041] Test item Test result Thermal conductivity (W / (m-K)) 0.031 Compressive strength (MPa) 1.05 Hydrophobic rate (%) 98.5 Ultraviolet aging resistance rate (500h, %) 96.1 Density (kg / m 3 )]]> 192 Comparative Example 4 only changes the segmented press forming process of the present scheme, adopts the conventional single press mode of the prior art, resulting in a compressive strength of 1.05 MPa, a decrease of 32.2% compared with Example 2; the thermal conductivity rises to 0.031 W / (m·K), an increase of 19.2% compared with Example 2. This is because under the single press mode, the air inside the slurry cannot be fully discharged, and small pores are easily formed, and the sudden application of temperature and pressure leads to uneven densification of the slurry, affecting the mechanical strength and reducing the thermal insulation effect. The data prove that the segmented press forming process of the present scheme solves the problem of the prior art that densification and exhaust are incompatible through the step-by-step design of low-temperature and low-pressure pre-pressing and high-temperature and high-pressure densification.

[0042] Comparative Example 5: Please refer to Figure 1 The present application provides a comparative scheme: raw material ratio: exactly the same as Example 2.

[0043] Production steps: except that the S5 step adopts constant temperature drying (directly dried at 85°C, vacuum degree-0.095MPa for 4.5h), the remaining steps are consistent with Example 2.

[0044] Test item Test result Thermal conductivity (W / (m-K)) 0.030 Compressive strength (MPa) 1.12 Hydrophobic rate (%) 98.2 Ultraviolet aging resistance rate (500h, %) 96.5 Density (kg / m 3 ) 190 Green body crack rate (%) 8.3 Comparative Example 5 replaces the gradient drying process of the present scheme with conventional constant temperature drying, resulting in a compressive strength of 1.12 MPa, a decrease of 26.3% compared with Example 2; the thermal conductivity rises to 0.030 W / (m·K), an increase of 15.4% compared with Example 2; and there is a 8.3% green body crack rate, while Example 2 has no visible cracks. This is because when constant temperature drying, the internal moisture of the green body rapidly evaporates, forming a large humidity gradient with the surface, resulting in stress concentration and cracks, which not only damages the structural integrity but also forms a heat conduction channel. The data prove that the gradient drying process of the present scheme solves the industry pain point of easy crack generation of the existing drying process through slow and uniform evaporation of water by stepwise heating, which is an important process to ensure the structural stability of the product.

[0045] Comparative Example 6: Please refer to Figure 1 The present application provides a comparative scheme: raw material ratio: exactly the same as Example 2.

[0046] Production steps: except for omitting the S6 anti-ultraviolet post-treatment step, cutting directly after forming, the remaining steps are consistent with Example 2.

[0047] Test item Test result Thermal conductivity (W / (m-K)) 0.027 Compressive strength (MPa) 1.48 Hydrophobic rate (%) 99.0 Ultraviolet aging resistance rate (500h, %) 82.6 Density (kg / m 3 ) 187 Comparative Example 6 omits the anti-ultraviolet post-processing step of the present solution. Although the short-term core performance (thermal conductivity, compressive strength, etc.) is close to that of Example 2, the anti-ultraviolet aging rate is only 82.6%, which is 15.1% lower than that of Example 2. This means that the thermal conductivity of the product will increase significantly after 500 hours of outdoor use, and the thermal insulation performance will be greatly degraded, which cannot meet the long-term service requirements of building materials. This data proves that the anti-ultraviolet post-processing step of the present solution is an innovative point designed to address the pain points of existing insulation boards, which have insufficient anti-ultraviolet performance and short service life. The protective barrier formed by the nano-silicon dioxide coating ensures the long-term stability of the product in complex outdoor environments.

[0048] Comparative Example 7: Please refer to Figure 1 The present solution provides a comparative solution: raw material ratio: composite modified aerogel: 18 parts (aerogel is modified by γ-glycidyl ether oxypropyl trimethoxysilane and KH570, total addition amount is 16% of the mass of the aerogel, mass ratio of 1:1); the remaining raw materials are exactly the same as Example 2.

[0049] Production steps: except for adding γ-glycidyl ether oxypropyl trimethoxysilane 0.81 kg and KH570 0.81 kg for composite modification in S1 step, the remaining steps are consistent with Example 2.

[0050] Test item Test result Thermal conductivity (W / (m-K)) 0.029 Compressive strength (MPa) 1.21 Hydrophobic rate (%) 98.8 Ultraviolet aging resistance rate (500h, %) 96.3 Density (kg / m 3 ) 191 Production process complexity (relative value) 1.8 Comparative Example 7 uses the common multi-modifier composite modification solution of existing technology to replace the single modified aerogel of the present solution. The results show that the thermal conductivity is 0.029 W / (m·K), which is 11.5% higher than Example 2; the compressive strength is 1.21 MPa, which is 20.4% lower than Example 2; and the production process complexity increases by 80% (relative value 1.8), which means that the production cost increases significantly. This is because there is a problem of insufficient synergy between multiple modifiers, which affects the dispersion effect of aerogel and increases the process steps and control difficulty. This data proves that the single modified aerogel design of the present solution simplifies the process and reduces costs while achieving better technical effects than the multi-modifier composite solution, solving the contradiction between the complexity of existing modification processes and poor results.

[0051] The technical scheme aims at the core pain points of the existing aerogel composite insulation board, such as complex modification process, insufficient mechanical properties of the substrate, poor adaptability of the binder, poor process stability, and insufficient long-term service performance. Through the synergistic design of single modified aerogel, optimized components and innovative process, the comprehensive performance is breakthroughly improved. The test results of embodiments 1-3 are consistent, which show that the product thermal conductivity is stably controlled at 0.024-0.028 W / (m·K), which is much lower than the general level of 0.035 W / (m·K) or more in the prior art; the compressive strength is not less than 1.35 MPa, meeting the stringent requirements of building exterior wall construction on mechanical strength; the hydrophobic rate is ≥98.5%, the ultraviolet aging resistance rate is ≥95.8%, and the density is ≤195 kg / m 3 , realizing the synergistic unity of low thermal conductivity, high compressive strength, high function, lightweight and long service life. This effect cannot be achieved by single optimization of a component or process in the prior art.

[0052] The comparison between comparative example 1 and embodiment 2 directly proves the core creativity of single modified aerogel. Comparative example 1 does not use γ-glycidoxypropyltrimethoxysilane modified aerogel. Only this change causes the thermal conductivity to rise to 0.038 W / (m·K), which is 46.2% higher than that of embodiment 2, the compressive strength decreases to 0.92 MPa, which is 39.5% lower than that of embodiment 2 and lower than the minimum standard of 1.0 MPa required by building construction, and the antibacterial rate is less than 91%, and the density increases to 208 kg / m 3 . This shows that the single modifier selected in the present scheme can efficiently solve the problem of aerogel particle agglomeration, and optimize the interfacial bonding force with other components, breaking the contradiction in the prior art that multiple modifiers are used for complex modification but it is difficult to balance the dispersion effect and process simplification. While reducing the production complexity, the insulation, mechanical and antibacterial properties are simultaneously improved.

[0053] Comparative example 2 uses conventional glass fiber and expanded perlite as substrate without plasma pretreatment, and the compressive strength is only 0.76 MPa, which is 50.0% lower than that of embodiment 2, the thermal conductivity rises to 0.035 W / (m·K), which is 34.6% higher than that of embodiment 2, and the density increases to 215 kg / m 3 , fully proving the innovation of the boron nitride reinforced substrate and the plasma pretreatment process designed in the present scheme. The tensile strength of boron nitride fiber is ≥3000 MPa, which is much higher than that of glass fiber ≤500 MPa. The multi-pore structure formed by hollow aluminum silicate microbeads and expanded shale not only provides stable skeleton support, but also optimizes the insulation system; the plasma pretreatment further improves the interfacial bonding force between the fibers and other components, solving the industry problem that the mechanical strength and insulation performance of the existing substrate cannot be compatible.

[0054] Comparative Example 3 uses a common epoxy resin to replace the polyurethane modified epoxy resin adhesive of the present application, resulting in a compressive strength of 0.88 MPa, a decrease of 42.1% compared to Example 2, a hydrophobic rate of 91.3% after 5 years, a decrease of 8.4% in long-term performance compared to Example 2, and a thermal conductivity of 0.032 W / (m·K), an increase of 19.2% compared to Example 2. This data highlights the technical advantages of the polyurethane modified epoxy resin adhesive, which has a molecular structure that combines flexibility and adhesion, can adapt to the interface characteristics of aerogel and boron nitride fibers, avoid the problem of brittleness and easy cracking after curing of conventional adhesives, and improve the long-term aging resistance of the product, ensuring the structural integrity and functional stability of the insulation board under long-term temperature changes and humidity erosion, solving the pain points of existing adhesives that meet short-term performance standards but fail in long-term service.

[0055] In addition, Examples 1-3 cover different intervals of raw material ratios, from basic ratios to high insulation ratios, all of which can achieve excellent performance, proving that the present application has the stability and universality required for industrial mass production. Single modified aerogel ensures uniform dispersion, boron nitride enhances the mechanical support of the substrate and pretreatment, polyurethane modified adhesive strengthens the interface bonding, and the segmented pressure and gradient drying process ensures the forming quality, and the anti-ultraviolet post-treatment improves the long-term use function. This combined design not only solves the multiple contradictions in the prior art, such as sacrificing mechanical properties for low thermal conductivity, reducing effects for process simplification, and ignoring long-term stability for short-term performance standards, but also simplifies the production process and reduces costs by replacing multiple modifiers with a single modification, providing a feasible path for the large-scale industrial application of aerogel composite insulation boards.

[0056] In order to further illustrate the beneficial technical effects of the aerogel composite insulation boards of the embodiments of the present application, the aerogel composite insulation boards involved in Examples 1-3 and Comparative Examples 1-7 were tested for relevant performance; the test methods are as follows: I. Thermal conductivity test Sample preparation: three 300mm x 300mm x 25mm samples were cut and polished, then equilibrated in a 25℃, 50% relative humidity environment for 24 hours. Test process: using the guarded hot plate method, set the cold plate temperature to 20℃ and the hot plate temperature to 40℃, record the data after the heat flux density is constant. Data processing: calculate according to the formula "thermal conductivity = (heat flux density x sample thickness) / temperature difference", take the average of the three samples.

[0057] II. Compressive strength test Sample preparation: select 5 samples of 100mm x 100mm x 50mm, measure the actual size and place in an environment of 25℃ and 50% relative humidity for 12h. Test process: use an electronic universal testing machine to apply pressure at a rate of 2mm / min until the sample breaks, and record the maximum pressure value. Data processing: calculate according to the formula "compressive strength = maximum pressure value / (actual length of sample x actual width of sample)", and take the average value after removing outliers.

[0058] III. Hydrophobicity test Sample preparation: select 3 samples of 200mm x 200mm x 20mm, dry at 80℃ until constant weight, then cool and weigh (m1). Test process: place the sample at an angle of 30°, spray deionized water at a rate of 10mL / min for 30min at a height of 300mm, wipe off the free moisture and weigh (m2). Data processing: calculate according to the formula "hydrophobicity = (1 - (m2 - m1) / m1) x 100%", and take the average value of 3 samples; for long-term testing, use a temperature and humidity cycle of "-20℃ freezing for 2h - 60℃ baking for 2h", and test every 3 months.

[0059] IV. Anti-UV aging rate test Sample preparation: select 3 samples of 300mm x 300mm x 25mm and place them in a UV aging test chamber. Test process: set the UV lamp power to 300W, wavelength to 290-400nm, temperature to 60℃, and relative humidity to 50%, and continuously age for 500h. Data processing: test the thermal conductivity of the sample after aging, and calculate according to the formula "anti-UV aging rate = (thermal conductivity before aging / thermal conductivity after aging) x 100%", and take the average value of 3 samples.

[0060] V. Density test Sample preparation: select 3 samples of 100mm x 100mm x 100mm, trim the edges, measure the actual size, and calculate the volume (V). Test process: use an electronic analytical balance to weigh the sample mass (m). Data processing: calculate according to the formula "density = sample mass (m) / sample volume (V)", and take the average value of 3 samples.

[0061] VI. Green body crack rate test Sample preparation: select 10 formed green bodies, and observe the surface and cross-section after demolding. Test process: use a magnifying glass (magnification 10x) to observe the number and length of cracks, and record the number of green bodies with visible cracks (length ≥ 0.5mm). Data processing: calculate according to the formula "green body crack rate = (number of green bodies with cracks / total number of green bodies) x 100%".

[0062] The above-mentioned are only embodiments of the present application, and common technical solutions or common knowledge in the scheme are not described in detail. It should be pointed out that, for those skilled in the art, without departing from the technical solutions of the present application, a number of modifications and improvements can be made, which should also be regarded as the protection scope of the present application, and these will not affect the effect and practicality of the patent. The protection scope claimed in the present application should be subject to the content of its claims, and the specific implementation mode and the like recorded in the specification can be used to explain the content of the claims.

Claims

1. An aerogel composite insulation board, characterized in that, The raw material components include the following parts by weight: 16-20 parts of composite modified aerogel, 48-58 parts of boron nitride reinforced substrate, 13-17 parts of polyurethane epoxy resin binder, and 6-9 parts of multifunctional additives. The composite modified aerogel was prepared by modifying aerogel with γ-glycidyl oxypropyltrimethoxysilane; The boron nitride reinforced substrate is composed of boron nitride fibers and composite porous particles mixed at a mass ratio of 1:1.1-1.

4. The boron nitride fibers have a diameter of 10-18 μm and a length of 2.5-4.5 mm. The composite porous particles are made by mixing hollow aluminosilicate microspheres and expanded shale at a mass ratio of 1:1.3-1.

6. The polyurethane epoxy resin adhesive is an industrial-grade polyurethane modified epoxy resin, and the particle size of the nano magnesium hydroxide is 45-75nm. The multifunctional additive is composed of nano-magnesium hydroxide and perfluorohexyltriethoxysilane mixed in a mass ratio of 3:1.1-1.

3.

2. The aerogel composite insulation board according to claim 1, characterized in that, In the composite porous particles, the hollow aluminosilicate microspheres have a particle size of 90-160 μm and a bulk density of 0.20-0.28 g / cm³. 3 The expanded shale has a grain size of 0.4-0.7 mm and a water content of ≤0.7%.

3. The aerogel composite insulation board according to claim 1, characterized in that, The solid content of polyurethane epoxy resin adhesive is 68-78%.

4. The aerogel composite insulation board according to claim 1, characterized in that, The purity of perfluorohexyltriethoxysilane is ≥98.8%, and the specific surface area of ​​nano-magnesium hydroxide is 22-28 m². 2 / g.

5. The aerogel composite insulation board according to claim 1, characterized in that, In the composite modified aerogel, the amount of γ-glycidoxypropyltrimethoxysilane added is 8-10% of the mass of the aerogel.

6. The manufacturing process of an aerogel composite insulation board according to any one of claims 1-5, characterized in that, Includes the following steps: S1: Preparation of composite modified aerogel: Disperse the aerogel in ethylene glycol monomethyl ether solution, add γ-glycidyl etheroxypropyltrimethoxysilane, stir and react at 62-68℃ for 3.2-4.2h, centrifuge after the reaction is completed, and vacuum dry at 78-88℃ for 3.8-4.8h to obtain composite modified aerogel; S2: Pretreatment of boron nitride reinforced substrate: Boron nitride fibers are subjected to low-temperature plasma surface treatment with a treatment power of 380-480W and a treatment time of 7-11min. The working gas is nitrogen with a gas flow rate of 18-24L / min. Hollow aluminosilicate microspheres and expanded shale are weighed according to the composite porous particle ratio and stirred at 200-250r / min for 15-20min to obtain mixed porous particles. The pretreated boron nitride fibers are mixed with the mixed porous particles and dried at 115-125℃ for 1.8-2.2h to obtain the pretreated boron nitride reinforced substrate. S3: Preparation of composite slurry: Mix the composite modified aerogel, pretreated boron nitride reinforced substrate, polyurethane epoxy resin binder and multifunctional additives according to the weight parts, add deionized water to adjust the slurry consistency to 95-115s, the amount of deionized water added is 11-15% of the total mass of composite slurry, stir at 480-530r / min for 42-48min to obtain a uniform composite slurry; S4: Segmented pressure molding: Pour the composite slurry into a mold of a preset size, first hold the pressure at 0.75-0.85MPa and 30-34℃ for 4.5-6.5min, then raise the temperature to 48-53℃ and pressurize to 0.95-1.05MPa for 5.5-7.5min to obtain the molded blank; S5: Gradient drying and curing: The molded preform is placed in a vacuum drying oven and dried for 4.2-4.8 hours at a temperature of 82-88℃ and a vacuum degree of -0.092 to -0.097MPa. The drying process adopts a step-by-step heating method: first, it is kept at 58℃ for 1.2 hours, then the temperature is increased to 68℃ and kept for 1.2 hours, and finally the temperature is increased to 82-88℃ and kept for 1.8-2.4 hours. After drying, it is naturally cooled to room temperature and demolded to obtain the initial product. S6: UV protection post-treatment: Spray a nano-silica UV protection coating onto the surface of the initial finished product. The coating thickness is 10-15μm, and the solid content of the nano-silica UV protection coating is 38-43%, of which the mass fraction of nano-silica is 0.4-0.6%. After spraying, dry at 88-93℃ for 1.8-2.3h, and then cut to the preset size to obtain the finished aerogel composite insulation board.

7. The production process of the aerogel composite insulation board according to claim 6, characterized in that, The amount of ethylene glycol monomethyl ether solution used in S1 is 6-8 times the mass of the aerogel, and the centrifugation speed is 8500-9500 r / min and the time is 18-22 min.

8. The production process of the aerogel composite insulation board according to claim 6, characterized in that, In S3, a 4-cup viscometer is used to test the consistency of the slurry, and the test temperature is 25-28℃.

9. The production process of the aerogel composite insulation board according to claim 6, characterized in that, The natural cooling rate of S5 is 6-12℃ / min, and demolding is completed when the temperature drops to 25-28℃.

10. The production process of the aerogel composite insulation board according to claim 6, characterized in that, The S6 is coated using air spraying, with a spraying pressure of 0.4-0.6 MPa and a spraying distance of 20-30 cm.

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