A fireproof and heat-insulating wall composite material and its preparation method

Abstract

This invention discloses a fireproof and heat-insulating wall composite material and its preparation method in the field of thermal insulation wall technology. The composite material comprises the following components by weight: 55-65 parts fly ash, 16-24 parts desulfurized gypsum, 5-10 parts reinforcing rock wool fiber, 13-20 parts cement, 4-7 parts lime, 7-13 parts modified phenolic resin, 0.2-0.5 parts curing agent, 3-6 parts hollow glass microspheres, and 34-40 parts water. This invention enhances the mechanical strength and interfacial adhesion of the composite material through an organic-inorganic hybrid network, a silicon oxide network, and N-phosphine, resulting in outstanding mechanical and thermal insulation performance. At the molecular level, it constructs a ternary hybrid crosslinked network of organosilicon-phenolic-phosphine, combined with a nano / micro porous structure and surface functionalization treatment, ultimately achieving a synergistic improvement in three major properties: high strength, ultra-low thermal conductivity, and excellent flame retardancy, fully meeting the dual requirements of energy conservation and safety in modern buildings.

Description

Technical Field

[0001] This invention belongs to the field of thermal insulation wall technology, specifically referring to a fireproof and thermal insulation wall composite material and its preparation method. Background Technology

[0002] In the development of the construction industry, the performance of wall materials is directly related to the energy efficiency and safety of buildings. Currently, building energy consumption accounts for a high proportion of total social energy consumption. As a core component of the building envelope, exterior walls account for 20%-30% of the total energy loss of the envelope. Therefore, high-efficiency insulation materials have become crucial for reducing building energy consumption. In recent years, numerous building fires both domestically and internationally have exposed the safety hazards of traditional insulation materials. The toxic gases and molten droplets released during the combustion of traditional organic insulation materials accelerate the spread of fire, causing serious casualties and property damage. This makes the synergy between insulation and fire resistance a core issue in the research and development of wall materials.

[0003] Rock wool fiber, as an excellent building insulation material, is widely used in the construction industry, especially in buildings with high insulation performance requirements. Rock wool fiber is produced by melting natural rocks (such as basalt and diabase), fiberizing them using high-speed centrifugal equipment, attaching an appropriate amount of binder, and then undergoing processes such as settling, curing, and cutting. Its superior thermal, acoustic, and fire-resistant properties make it a preferred material for many construction projects.

[0004] Rock wool fiber has an extremely low thermal conductivity, typically between 0.035 and 0.045 W / (m·K), making it an excellent thermal insulation material. It effectively prevents heat loss from indoors and cold air infiltration from outdoors, maintaining a stable indoor temperature and thus improving energy efficiency and reducing heating and cooling energy consumption. Since its main raw material is natural rock, rock wool fiber itself has excellent fire resistance. As a non-combustible material, it can typically withstand temperatures up to approximately 1000℃, playing a role in preventing the spread of fire in buildings. The rock wool fiber structure has good sound absorption capabilities, reducing noise transmission between different rooms and floors within a building. Therefore, rock wool fiber is often used in the structure of walls, ceilings, or floors in buildings requiring noise reduction or improved acoustics. Rock wool fiber has good resistance to acid and alkali corrosion, typically maintaining stable performance under various harsh environments. Its lightweight, dimensionally stable, and easy-to-cut nature makes construction relatively simple and better suited to various building needs.

[0005] Despite the wide application of rock wool fiber in the construction industry, it also presents certain technical limitations and challenges: Rock wool fibers easily absorb moisture in high-humidity environments, leading to a decrease in their thermal insulation performance. Therefore, additional moisture-proofing treatment is required during application to prevent further reduction in its insulation properties. Traditional rock wool fibers may lack sufficient mechanical strength, making them susceptible to damage during transportation and construction. For structures subjected to high loads or prolonged pressure, they may not fully meet the requirements. Furthermore, over long-term use, rock wool fibers may undergo changes in size and shape due to environmental variations, thus affecting their effectiveness as an insulation material in buildings. Summary of the Invention

[0006] In view of the above situation and to overcome the defects of the prior art, the present invention provides a fireproof and heat-insulating wall composite material and its preparation method.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The present invention proposes a fireproof and heat-insulating wall composite material, wherein the composite wall material comprises the following components in parts by weight: 55-65 parts fly ash, 16-24 parts desulfurized gypsum, 5-10 parts reinforcing rock wool fiber, 13-20 parts cement, 4-7 parts lime, 7-13 parts modified phenolic resin, 0.2-0.5 parts curing agent, 3-6 parts hollow glass microspheres, and 34-40 parts water;

[0008] Preferably, the raw materials for preparing the modified phenolic resin include the following components in parts by weight: 6.8 parts of bis[3-(triethoxysilane)]propylamine, 3.0-3.5 parts of epichlorohydrin, 4.5-5.0 parts of phenol, and 1.5-2 parts of formaldehyde;

[0009] Preferably, the raw materials for preparing the reinforced rock wool fiber include the following components in parts by weight: 8-12 parts activated rock wool fiber, 1.5 parts N-phosphorylated siloxane, and 4.0-9.5 parts tetraethoxysilane;

[0010] Preferably, the preparation method of the modified phenolic resin specifically includes the following steps:

[0011] S1. Dissolve bis[3-(triethoxysilane)]propylamine in DMSO, purge with flowing nitrogen, add triethylamine, stir, and add epichlorohydrin solution dropwise. After the addition is complete, carry out the first-order reaction. After the reaction is complete, add catalyst, mix well, and raise the reaction temperature to carry out the second-order reaction. After the reaction is complete, add deionized water to dilute, add ethyl acetate for extraction, separate the organic phase, dry with anhydrous magnesium sulfate, and concentrate under reduced pressure to obtain organosilicon polymer.

[0012] S2. Place phenol and formaldehyde in a flask, adjust the pH to 8.5-9.0, carry out a pre-crosslinking reaction, add the organosilicon polymer prepared in step S1, carry out a crosslinking condensation reaction, remove excess reaction solvent by rotary evaporation, and obtain modified phenolic resin.

[0013] Preferably, in step S1, the amount of triethylamine added is 0.5-1% of the mass of bis[3-(triethoxysilane)]propylamine;

[0014] Preferably, in step S1, the amount of catalyst added is 0.15%-0.25% of the mass of bis[3-(triethoxysilane)]propylamine;

[0015] Preferably, in step S1, the reaction temperature of the first-order reaction is 30-50℃, the reaction time of the first-order reaction is 1-2h, the reaction temperature of the second-order reaction is 70-90℃, and the reaction time of the second-order reaction is 6-10h.

[0016] Preferably, in step S2, the reaction temperature of the pre-crosslinking reaction is 60-80℃, and the reaction time of the pre-crosslinking reaction is 20-60 min;

[0017] Preferably, in step S2, the reaction temperature of the crosslinking condensation reaction is 80-90℃, and the reaction time is 2-3h;

[0018] Preferably, the method for preparing the reinforced rock wool fiber specifically includes the following steps:

[0019] S3. Rock wool fibers are immersed in NaOH aqueous solution. After stirring to completely disperse the rock wool fibers in NaOH aqueous solution, the temperature is raised to carry out the alkali treatment reaction. After the reaction is completed, the fibers are washed until neutral and then dried to obtain activated rock wool fibers.

[0020] S4. Dissolve γ-aminopropyltriethoxysilane in anhydrous DCM. Under ice-water bath conditions, slowly add phosphorus oxychloride. After the addition is complete, continue stirring and raise the temperature to carry out the condensation reaction. After the reaction is complete, add anhydrous ethanol to passivate P-Cl. Add deionized water and stir. Let stand for separation. Take the organic phase, wash it, dry it to remove water, and concentrate it under reduced pressure to obtain N-phosphorylated siloxane.

[0021] S5. Dissolve the N-phosphorylated siloxane and tetraethoxysilane prepared in step S4 in anhydrous ethanol, place them in an ice-water bath, add deionized water, adjust the pH to 2-4, stir until the reaction system is homogeneous, add ammonia to adjust the pH of the reaction system to 6.0-6.5, raise the temperature to carry out the condensation reaction, after the reaction is completed, add the activated rock wool fiber prepared in step S3, vacuum the activated rock wool fiber to fully impregnate it, let it stand and age, replace the solvent with anhydrous ethanol and anhydrous acetone in sequence, and dry it with supercritical CO2 to obtain reinforced rock wool fiber;

[0022] Preferably, in step S3, the mass concentration of NaOH in the NaOH aqueous solution is 5%-10%;

[0023] Preferably, in step S3, the reaction temperature of the alkali treatment reaction is 50-70℃, and the reaction time of the alkali treatment reaction is 0.5-2h;

[0024] Preferably, in step S4, the mass concentration of the γ-aminopropyltriethoxysilane in anhydrous DCM is 30-50 mg / mL;

[0025] Preferably, in step S4, the mass ratio of γ-aminopropyltriethoxysilane to phosphorus oxychloride is 1.3-1.4:1;

[0026] Preferably, in step S4, the reaction temperature of the condensation reaction is 20-30°C, and the reaction time of the condensation reaction is 3-4 hours.

[0027] Preferably, in step S5, the reaction temperature of the condensation reaction is 20-30°C, and the reaction time is 40-60 min.

[0028] This invention also provides a method for preparing a fireproof and thermally insulated wall composite material, specifically including the following steps:

[0029] ① Pour fly ash, desulfurized gypsum, cement, lime, and hollow glass microspheres into a twin-shaft mixer and mix at 60-80 rpm for 5-10 minutes to obtain inorganic dry material;

[0030] ② Mix the modified phenolic resin and curing agent to obtain a premixed liquid. Slowly spray the premixed liquid into the inorganic dry material prepared in step ①. Stir at 120-150 rpm for 3-5 minutes. Then add the reinforcing rock wool fiber and water. Stir at 200-250 rpm for 8-12 minutes. Continue mixing until there are no dry powder lumps and no free water to obtain the premixed material.

[0031] ③ Place the premixed material prepared in step ② into a mold, mold it at room temperature, and then cure it to obtain the wall composite material;

[0032] Preferably, in step ③, the parameters for the maintenance treatment include:

[0033] Low-temperature pre-curing: After molding, place in an environment of 20-25℃ and 60%-70% relative humidity for 6-8 hours;

[0034] Medium temperature curing: In the curing box, cure at 40-45℃ for 4-6 hours, then raise the temperature to 55-60℃ and cure for 8-10 hours;

[0035] Room temperature maintenance: 20-25℃ in a well-ventilated environment, maintain for 7-10 days, spray water daily to keep the surface moist.

[0036] The beneficial effects achieved by this invention are as follows:

[0037] This invention provides a fireproof and thermally insulating wall composite material and its preparation method. The mechanical strength and interfacial adhesion are enhanced through an organic-inorganic hybrid network, a silicon oxide network, and N-phosphosilane, resulting in outstanding mechanical and thermal insulation properties. In this invention, a three-dimensional cross-linked network with Si-OC and Si-O-Si is formed through a condensation reaction between an organosilicon polymer and phenolic resin. This retains the high cross-linking and high rigidity of the phenolic resin while introducing more elastic organosilicon segments, significantly improving the fracture toughness and crack propagation resistance of the matrix. After alkali treatment of rock wool fibers, N-phosphosiloxane and tetraethoxysilane are attached to their surface. The sol-gel, through the hydrolysis and condensation reaction of siloxanes, forms a functionalized SiO2 sol-gel coating on the surface of rock wool fibers. This film has strong chemical bonds (covalent bonds or extremely strong hydrogen bonds) with the modified phenolic resin molecules, significantly improving the interfacial bonding strength of the fiber-matrix interface, thus significantly increasing the compressive and flexural strength of the board and preventing fiber-matrix debonding under load. Supercritical CO2 drying removes the solvent without damaging the fiber pores, ensuring accurate positioning of the fiber bundles and resin network before curing, allowing for full resin impregnation without structural collapse. This results in a highly uniform fiber-matrix composite structure inside the board, leading to higher load-bearing efficiency and robust overall mechanical properties. During curing, the modified phenolic resin and organosilicon network solidify a large number of micron and nano-sized pores within the matrix. Combined with the rock wool fiber's inherent pores preserved by supercritical CO2 drying, this forms a secondary porous structure. Air within the pores is a highly poor thermal conductor, and the pore wall interfaces in the porous structure continuously scatter phonons, effectively suppressing solid-phase thermal conduction. The Si-O-Si and PO-Si bonds and interfacial film at the interface between organosilicon-phenolic resin and fiber form an interface layer with high thermal resistance, further hindering the direct transfer of heat between the fiber and the matrix. Surface functionalization treatment imparts good hydrophobicity to the fiber and resin system. At the molecular level, a ternary hybrid crosslinking network of organosilicon-phenolic resin-phosphorus is constructed. Combined with the nano / micro porous structure and surface functionalization treatment, the three major properties of high strength, ultra-low thermal conductivity and excellent flame retardancy are synergistically improved, which fully meets the dual requirements of energy conservation and safety in modern buildings. Attached Figure Description

[0038] Figure 1 The graph shows the thermal conductivity results of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3 of this invention.

[0039] Figure 2 The graphs show the mechanical properties of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3 of this invention.

[0040] Figure 3 The thermogravimetric curves are those of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3 of this invention.

[0041] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. Detailed Implementation

[0042] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those familiar to those skilled in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to this invention. The preferred embodiments and materials described herein are for illustrative purposes only and do not limit the scope of this application.

[0044] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; unless otherwise specified, the experimental materials and test strains used in the following examples were purchased from commercial channels.

[0045] Example 1

[0046] This embodiment provides a fireproof and heat-insulating wall composite material, specifically comprising the following components by weight: 55 parts fly ash, 24 parts desulfurized gypsum, 10 parts reinforcing rock wool fiber, 15 parts cement, 7 parts lime, 10 parts modified phenolic resin, 0.4 parts curing agent, 4 parts hollow glass microspheres, and 40 parts water.

[0047] The raw materials for preparing modified phenolic resin include the following components in parts by weight: 6.8 parts of bis[3-(triethoxysilane)]propylamine, 3.0 parts of epichlorohydrin, 4.5 parts of phenol, and 1.6 parts of formaldehyde;

[0048] The raw materials for preparing reinforced rock wool fiber include the following components in parts by weight: 10 parts activated rock wool fiber, 1.5 parts N-phosphorylated siloxane, and 9.4 parts tetraethoxysilane;

[0049] The preparation method of modified phenolic resin specifically includes the following steps:

[0050] S1. Accurately weigh 6.8 g of bis[3-(triethoxysilane)]propylamine and place it in a flask. Add 100 mL of DMSO to fully dissolve the bis[3-(triethoxysilane)]propylamine. Then, introduce flowing nitrogen gas and add 40 mg of triethylamine. Stir at 400 rpm until the mixture is homogeneous. Dissolve 3.0 g of epichlorohydrin in 50 mL of DMSO to obtain an epichlorohydrin solution. Add the solution dropwise to the reaction system at a rate of 1.0 mL / min. After the addition is complete, raise the reaction temperature to 40 °C to carry out the first-order reaction. After reacting for 2 hours, cool to room temperature and add 10 mg of aluminum trichloride. Mix well and raise the reaction temperature to 80 °C to carry out the second-order reaction. After reacting for 8 hours, cool the reaction system to room temperature and add 100 mL of deionized water to dilute the reaction system. Add ethyl acetate with twice the volume of deionized water for extraction. Shake thoroughly to separate the organic phase. Dry the organic phase with anhydrous magnesium sulfate and concentrate under reduced pressure to remove excess reaction solvent to obtain the organosilicon polymer.

[0051] S2. Accurately place 4.5g of phenol and 4.3mL of formaldehyde aqueous solution into a flask, add 50mL of deionized water, adjust the pH of the reaction system to 8.5 with 0.1mol / L NaOH aqueous solution, stir at 300rpm, raise the reaction temperature to 70℃ for pre-crosslinking reaction, after reacting for 40min, add the organosilicon polymer prepared in step S1, continue to raise the temperature to 80℃, continue to stir for crosslinking condensation reaction, after reacting for 3h, remove excess reaction solvent by rotary evaporation to obtain modified phenolic resin;

[0052] The preparation method of reinforced rock wool fiber specifically includes the following steps:

[0053] S3. Accurately weigh 10g of rock wool fiber and immerse it in 100mL of 0.1M NaOH aqueous solution. Stir at 500rpm until the rock wool fiber is completely and evenly dispersed. Then, raise the reaction temperature to 50℃ and carry out the alkali treatment reaction. After reacting for 2 hours, filter the solution, take out the rock wool fiber, wash it with deionized water until neutral, and place it in a hot air drying oven at 30℃ overnight to obtain activated rock wool fiber.

[0054] S4. After vacuum drying the reactor at 120℃ for 2 hours, introduce flowing nitrogen gas into the reactor and flush the reactor tubing with anhydrous DCM. Transfer the reactor to an ice-water bath, maintaining a nitrogen atmosphere. Add 7.3 mL of γ-aminopropyltriethoxysilane to the reactor, followed by 150 mL of anhydrous DCM. Stir at 200 rpm until the reaction system is homogeneous. Slowly add 3.22 mL of phosphorus oxychloride at a rate of 0.1 mL / min, and continue stirring for 1 hour. Then, raise the reaction temperature to 2... The condensation reaction was carried out at 5℃. After 4 hours of reaction, 30 mL of anhydrous ethanol was added to passivate the P-Cl bond. Then, 100 mL of deionized water was added and the mixture was slowly stirred at 50 rpm for 30 minutes. The reaction system was then transferred to a separatory funnel and allowed to stand for 2 hours to separate into layers. The organic phase was washed with 0.1 M NaHCO3 aqueous solution until neutral, and then washed with deionized water to remove impurities. The separated organic phase was dried with anhydrous MgSO4 and concentrated under reduced pressure to remove the solvent. After purification, N-phosphorylated siloxane was obtained.

[0055] S5. Accurately weigh 1.5g of N-phosphorylated siloxane and 9.4g of tetraethoxysilane prepared in step S4 and place them in a flask. Add 100mL of anhydrous ethanol and place the flask in an ice-water bath. Stir at 150rpm to mix the reaction system evenly. Then, add 10mL of deionized water dropwise at 1mL / min. Adjust the pH to 2 with 0.1M HCl aqueous solution. Continue stirring in the ice-water bath for 20min. Adjust the pH of the reaction system to 6.5 with 0.02M ammonia aqueous solution. Raise the reaction temperature to 25℃ to carry out the condensation reaction. After reacting for 60min, add 10g of activated rock wool fiber prepared in step S3. Vacuum the activated rock wool fiber to fully impregnate it. Let it stand at room temperature for 1h. Then, age it in the original solvent system. After aging in a water bath at 40℃ for 12h, replace the solvent with anhydrous ethanol, anhydrous acetone, and anhydrous methanol in sequence. After each 6h, perform supercritical CO2 drying to obtain reinforced rock wool fiber.

[0056] This embodiment also provides a method for preparing a fireproof and heat-insulating wall composite material, which specifically includes the following steps:

[0057] ① Screen fly ash with a particle size ≤0.15mm, dry it in an oven at 105℃ for 3 hours, and set it aside. Take desulfurized gypsum, crush it to a particle size ≤0.2mm, pass it through a 40-mesh sieve to break up any lumps, and dry it until the moisture content is ≤8%, and set it aside. Cement, lime, and hollow glass microspheres are all passed through a 30-mesh sieve to remove impurities and set them aside. Pour fly ash, desulfurized gypsum, cement, lime, and hollow glass microspheres into a twin-shaft mixer and mix them at 60rpm for 10 minutes to obtain inorganic dry material.

[0058] ② Take the modified phenolic resin and curing agent and mix them to obtain a premixed liquid. Slowly spray it into the inorganic dry material prepared in step ①. Stir at 150 rpm for 3 minutes, then add the reinforcing rock wool fiber and water. Stir at 250 rpm for 8 minutes and continue mixing until there are no dry powder lumps and no free water to obtain the premixed material.

[0059] ③ Place the premixed material prepared in step ② into a mold, and after molding at room temperature, perform curing treatment. Low temperature pre-curing: after molding, place it in an environment of 25℃ and 70% relative humidity for 6 hours. Medium temperature curing: in a curing chamber, cure at 45℃ for 4 hours, then raise the temperature to 60℃ for 8 hours. Room temperature curing: in a ventilated environment at 25℃, cure for 7 days, spray water every day to keep the surface moist, and obtain the wall composite material.

[0060] Example 2

[0061] This embodiment provides a fireproof and heat-insulating wall composite material, specifically comprising the following components by weight: 60 parts fly ash, 16 parts desulfurized gypsum, 5 parts reinforcing rock wool fiber, 13 parts cement, 4 parts lime, 7 parts modified phenolic resin, 0.2 parts curing agent, 6 parts hollow glass microspheres, and 34 parts water.

[0062] The raw materials for preparing modified phenolic resin include the following components in parts by weight: 6.8 parts of bis[3-(triethoxysilane)]propylamine, 3.1 parts of epichlorohydrin, 4.8 parts of phenol, and 1.85 parts of formaldehyde;

[0063] The raw materials for preparing reinforced rock wool fiber include the following components in parts by weight: 8 parts activated rock wool fiber, 1.5 parts N-phosphorylated siloxane, and 6.8 parts tetraethoxysilane;

[0064] The preparation method of modified phenolic resin specifically includes the following steps:

[0065] S1. Accurately weigh 6.8 g of bis[3-(triethoxysilane)]propylamine and place it in a flask. Add 100 mL of DMSO to fully dissolve the bis[3-(triethoxysilane)]propylamine. Then, introduce flowing nitrogen gas and add 50 mg of triethylamine. Stir at 400 rpm until the mixture is homogeneous. Dissolve 3.1 g of epichlorohydrin in 50 mL of DMSO to obtain an epichlorohydrin solution. Add the solution dropwise to the reaction system at a rate of 1.0 mL / min. After the addition is complete, raise the reaction temperature to 30 °C to carry out the first-order reaction. After reacting for 2 h, cool to room temperature and add 14 mg of aluminum trichloride. Mix well and raise the reaction temperature to 70 °C to carry out the second-order reaction. After reacting for 10 h, cool the reaction system to room temperature and add 100 mL of deionized water to dilute the reaction system. Add ethyl acetate with twice the volume of deionized water for extraction. Shake thoroughly to separate the organic phase. Dry the organic phase with anhydrous magnesium sulfate and concentrate under reduced pressure to remove excess reaction solvent to obtain the organosilicon polymer.

[0066] S2. Accurately place 4.8g of phenol and 5.0mL of formaldehyde aqueous solution into a flask, add 50mL of deionized water, adjust the pH of the reaction system to 8.5 with 0.1mol / L NaOH aqueous solution, stir at 300rpm, raise the reaction temperature to 60℃ for pre-crosslinking reaction, after reacting for 60min, add the organosilicon polymer prepared in step S1, continue to raise the temperature to 85℃, continue to stir for crosslinking condensation reaction, after reacting for 2.5h, remove excess reaction solvent by rotary evaporation to obtain modified phenolic resin;

[0067] S3. Accurately weigh 10g of rock wool fiber and immerse it in 500mL of 0.1M NaOH aqueous solution. Stir at 500rpm until the rock wool fiber is completely and evenly dispersed. Then, raise the reaction temperature to 70℃ and carry out the alkali treatment reaction. After reacting for 0.5h, filter, take out the rock wool fiber, wash it with deionized water until neutral, and place it in a hot air drying oven to dry overnight at 30℃ to obtain activated rock wool fiber.

[0068] S4. After vacuum drying the reactor at 120℃ for 2 hours, introduce flowing nitrogen gas into the reactor and flush the reactor tubing with anhydrous DCM. Transfer the reactor to an ice-water bath, maintaining a nitrogen atmosphere. Add 5.4 mL of γ-aminopropyltriethoxysilane to the reactor, followed by 150 mL of anhydrous DCM. Stir at 200 rpm until the reaction system is homogeneous. Slowly add 2.33 mL of phosphorus oxychloride at a rate of 0.1 mL / min, and continue stirring for 1 hour. Then, raise the reaction temperature to 2... The condensation reaction was carried out at 5℃. After 4 hours of reaction, 30 mL of anhydrous ethanol was added to passivate P-Cl. Then, 100 mL of deionized water was added and the mixture was slowly stirred at 50 rpm for 30 minutes. The reaction system was then transferred to a separatory funnel and allowed to stand for 2 hours to separate into layers. The organic phase was washed with 0.1 M NaHCO3 aqueous solution until neutral, and then washed with deionized water to remove impurities. The separated organic phase was dried with anhydrous MgSO4 and concentrated under reduced pressure to remove the solvent. After purification, N-phosphorylated siloxane was obtained.

[0069] S5. Accurately weigh 1.5g of N-phosphorylated siloxane and 6.77g of tetraethoxysilane prepared in step S4 and place them in a flask. Add 100mL of anhydrous ethanol and place the flask in an ice-water bath. Stir at 150rpm to mix the reaction system evenly. Then, add 10mL of deionized water dropwise at 1mL / min. Adjust the pH to 3 with 0.1M HCl aqueous solution. Continue stirring in the ice-water bath for 20min. Adjust the pH of the reaction system to 6.3 with 0.02M ammonia aqueous solution. Raise the reaction temperature to 20℃ to carry out the condensation reaction. After reacting for 50min, add 12g of activated rock wool fiber prepared in step S3. Vacuum the activated rock wool fiber to fully impregnate it. Let it stand at room temperature for 1h. Then, age it in the original solvent system. After aging in a water bath at 40℃ for 12h, replace the solvent with anhydrous ethanol, anhydrous acetone, and anhydrous methanol in sequence. After each 6h, perform supercritical CO2 drying to obtain reinforced rock wool fiber.

[0070] This embodiment also provides a method for preparing a fireproof and heat-insulating wall composite material, which specifically includes the following steps:

[0071] ① Screen fly ash with a particle size ≤0.15mm, dry it in an oven at 105℃ for 3 hours, and set it aside. Take desulfurized gypsum, crush it to a particle size ≤0.2mm, pass it through a 40-mesh sieve to break up any lumps, and dry it until the moisture content is ≤8%, and set it aside. Cement, lime, and hollow glass microspheres are all passed through a 30-mesh sieve to remove impurities and set them aside. Pour fly ash, desulfurized gypsum, cement, lime, and hollow glass microspheres into a twin-shaft mixer and mix them at 70rpm for 8 minutes to obtain inorganic dry material.

[0072] ② Mix the modified phenolic resin and curing agent to obtain a premixed liquid, and then slowly spray it into the inorganic dry material prepared in step ①. Stir at 130 rpm for 4 minutes, then add the reinforcing rock wool fiber and water, and stir at 230 rpm for 10 minutes. Continue mixing until there are no dry powder lumps and no free water to obtain the premixed material.

[0073] ③ Place the premixed material prepared in step ② into a mold, and after molding at room temperature, perform curing treatment. Low temperature pre-curing: after molding, place it in an environment of 20℃ and 60% relative humidity for 8 hours. Medium temperature curing: in a curing chamber, cure at 40℃ for 6 hours, then raise the temperature to 55℃ for 10 hours. Room temperature curing: in a ventilated environment at 20℃, cure for 10 days, spray water every day to keep the surface moist, and obtain the wall composite material.

[0074] Example 3

[0075] This embodiment provides a fireproof and heat-insulating wall composite material, specifically comprising the following components by weight: 65 parts fly ash, 20 parts desulfurized gypsum, 8 parts reinforcing rock wool fiber, 20 parts cement, 6 parts lime, 13 parts modified phenolic resin, 0.5 parts curing agent, 3 parts hollow glass microspheres, and 37 parts water.

[0076] The raw materials for preparing modified phenolic resin include the following components in parts by weight: 6.8 parts of bis[3-(triethoxysilane)]propylamine, 3.4 parts of epichlorohydrin, 5.0 parts of phenol, and 2.0 parts of formaldehyde;

[0077] The raw materials for preparing reinforced rock wool fiber include the following components in parts by weight: 12 parts activated rock wool fiber, 1.5 parts N-phosphorylated siloxane, and 4.2 parts tetraethoxysilane;

[0078] The preparation method of modified phenolic resin specifically includes the following steps:

[0079] S1. Accurately weigh 6.8 g of bis[3-(triethoxysilane)]propylamine and place it in a flask. Add 100 mL of DMSO to fully dissolve the bis[3-(triethoxysilane)]propylamine. Then, introduce flowing nitrogen gas and add 60 mg of triethylamine. Stir at 400 rpm until the mixture is homogeneous. Dissolve 3.4 g of epichlorohydrin in 50 mL of DMSO to obtain an epichlorohydrin solution. Add the solution dropwise to the reaction system at a rate of 1.0 mL / min. After the addition is complete, raise the reaction temperature to 50 °C to carry out the first-order reaction. After reacting for 1 h, cool to room temperature and add 17 mg of aluminum trichloride. Mix well and raise the reaction temperature to 90 °C to carry out the second-order reaction. After reacting for 6 h, cool the reaction system to room temperature and add 100 mL of deionized water to dilute the reaction system. Add ethyl acetate with twice the volume of deionized water for extraction. Shake thoroughly to separate the organic phase. Dry the organic phase with anhydrous magnesium sulfate and concentrate under reduced pressure to remove excess reaction solvent to obtain the organosilicon polymer.

[0080] S2. Accurately place 5.0g of phenol and 5.57mL of formaldehyde aqueous solution into a flask, add 50mL of deionized water, adjust the pH of the reaction system to 8.5 with 0.1mol / L NaOH aqueous solution, stir at 300rpm, raise the reaction temperature to 80℃ for pre-crosslinking reaction, after 20min of reaction, add the organosilicon polymer prepared in step S1, continue to raise the temperature to 90℃, continue to stir for crosslinking condensation reaction, after 2h of reaction, remove excess reaction solvent by rotary evaporation to obtain modified phenolic resin;

[0081] S3. Accurately weigh 10g of rock wool fiber and immerse it in 250mL of 0.1M NaOH aqueous solution. Stir at 500rpm until the rock wool fiber is completely and evenly dispersed. Then, raise the reaction temperature to 60℃ and carry out the alkali treatment reaction. After reacting for 1 hour, filter the solution, take out the rock wool fiber, wash it with deionized water until neutral, and place it in a hot air drying oven at 30℃ overnight to obtain activated rock wool fiber.

[0082] S4. After vacuum drying the reactor at 120℃ for 2 hours, introduce flowing nitrogen gas into the reactor and flush the reactor tubing with anhydrous DCM. Transfer the reactor to an ice-water bath, maintaining a nitrogen atmosphere. Add 6.35 mL of γ-aminopropyltriethoxysilane to the reactor, along with 150 mL of anhydrous DCM. Stir at 200 rpm until the reaction system is homogeneous. Slowly add 2.60 mL of phosphorus oxychloride at a rate of 0.1 mL / min, and continue stirring for 1 hour. Then, raise the reaction temperature to... The condensation reaction was carried out at 25℃. After 4 hours of reaction, 30 mL of anhydrous ethanol was added to passivate P-Cl. Then, 100 mL of deionized water was added and the mixture was stirred slowly at 50 rpm for 30 minutes. The reaction system was then transferred to a separatory funnel and allowed to stand for 2 hours to separate into layers. The organic phase was washed with 0.1 M NaHCO3 aqueous solution until neutral, and then washed with deionized water to remove impurities. The separated organic phase was dried with anhydrous MgSO4 and concentrated under reduced pressure to remove the solvent. After purification, N-phosphorylated siloxane was obtained.

[0083] S5. Accurately weigh 1.5g of N-phosphorylated siloxane and 4.17g of tetraethoxysilane prepared in step S4 and place them in a flask. Add 100mL of anhydrous ethanol and place the flask in an ice-water bath. Stir at 150rpm to mix the reaction system evenly. Then, add 10mL of deionized water dropwise at 1mL / min. Adjust the pH to 4 with 0.1M HCl aqueous solution. Continue stirring in the ice-water bath for 20min. Adjust the pH of the reaction system to 6.0 with 0.02M ammonia aqueous solution. Raise the reaction temperature to 30℃ to carry out the condensation reaction. After reacting for 40min, add 8g of activated rock wool fiber prepared in step S3. Vacuum the activated rock wool fiber to fully impregnate it. Let it stand at room temperature for 1h. Then, age it in the original solvent system. After aging in a water bath at 40℃ for 12h, replace the solvent with anhydrous ethanol, anhydrous acetone, and anhydrous methanol in sequence. After each 6h, perform supercritical CO2 drying to obtain reinforced rock wool fiber.

[0084] This embodiment also provides a method for preparing a fireproof and heat-insulating wall composite material, which specifically includes the following steps:

[0085] ① Screen fly ash with a particle size ≤0.15mm, dry it in an oven at 105℃ for 3 hours, and set it aside. Take desulfurized gypsum, crush it to a particle size ≤0.2mm, pass it through a 40-mesh sieve to break up any lumps, and dry it until the moisture content is ≤8%, and set it aside. Cement, lime, and hollow glass microspheres are all passed through a 30-mesh sieve to remove impurities and set them aside. Pour fly ash, desulfurized gypsum, cement, lime, and hollow glass microspheres into a twin-shaft mixer and mix them at 80rpm for 5 minutes to obtain inorganic dry material.

[0086] ② Take the modified phenolic resin and curing agent and mix them to obtain a premixed liquid. Slowly spray it into the inorganic dry material prepared in step ①. Stir at 150 rpm for 3 minutes, then add the reinforcing rock wool fiber and water. Stir at 200 rpm for 12 minutes and continue mixing until there are no dry powder lumps and no free water to obtain the premixed material.

[0087] ③ Place the premixed material prepared in step ② into a mold, and after molding at room temperature, perform curing treatment. Low temperature pre-curing: after molding, place it in an environment of 25℃ and 60% relative humidity for 7 hours. Medium temperature curing: in a curing chamber, cure at 40℃ for 6 hours, then raise the temperature to 60℃ for 10 hours. Room temperature curing: in a ventilated environment of 25℃, cure for 7 days, spray water every day to keep the surface moist, and obtain the wall composite material.

[0088] Comparative Example 1

[0089] This comparative example provides a wall composite material and its preparation method. The only difference between this example and Example 1 is that, in all components of the wall composite material, the modified phenolic resin described in Example 1 is replaced with the same weight parts of commercially available phenolic resin, while the remaining components and their contents are the same as in Example 1.

[0090] Comparative Example 2

[0091] This comparative example provides a wall composite material and its preparation method. The only difference between this example and Example 1 is that, in all components of the wall composite material, the reinforcing rock wool fiber described in Example 1 is replaced with commercially available rock wool fiber in the same weight proportions, while the remaining components and their contents are the same as in Example 1.

[0092] Comparative Example 3

[0093] This comparative example provides a wall composite material and its preparation method. The only difference between this example and Example 1 is that the raw materials for preparing the reinforcing rock wool fiber do not contain N-phosphorylated siloxane, but are supplemented with the same weight parts of tetraethoxysilane. The remaining components and their contents are the same as in Example 1.

[0094] Experimental Example 1

[0095] This experiment tests the thermal insulation performance of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3. A DRPLⅢ flat plate heat flow meter is used to test the thermal conductivity of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3. The wall composite materials are used as test samples.

[0096] Figure 1The figure shows the thermal conductivity results of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3 of the present invention. As shown in the figure, the thermal conductivity of the wall composite materials prepared in Examples 1-3 of the present invention is significantly lower than that of the wall composite materials prepared in Comparative Examples 1-3. In the embodiments of the present invention, modified phenolic resin is used to introduce a Si-O-Si crosslinking network, which will form a large number of micron or even nano-sized voids in the resin matrix. Heat propagation in the solid phase mainly relies on the vibration of phonons. When encountering these voids and interfaces, it will be frequently scattered and reflected, thereby effectively suppressing solid phase heat conduction. At the same time, the rock wool fiber composited with SiO2 aerogel has a further enhancing effect on thermal insulation performance.

[0097] Experiment Example 2

[0098] This experiment tests the mechanical properties of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3:

[0099] Compressive strength: According to GB / T50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete", standard specimens were prepared for the wall composite materials of Examples 1-3 and Comparative Examples 1-3, respectively. Five parallel specimens were prepared for each group of samples. The specimen size was 100mm×100mm×100mm cube. After molding, the specimens were cured according to the corresponding curing process. The standard specimens were placed in the center of the lower platen of the universal testing machine, ensuring that the upper and lower surfaces of the specimens were completely in contact with the platen without tilting or offset. The loading rate was set to 0.8MPa / s. The testing machine was started and the load was uniformly applied until the specimen failed (manifested as cracking, disintegration, or a decrease in load to 80% of the maximum load). The maximum failure load (unit: N) was recorded. The compressive strength was calculated according to the formula:

[0100] ;

[0101] f c F is the compressive strength (MPa), F is the maximum failure load (N), and A is the area of ​​the specimen subjected to pressure (mm²). 2 );

[0102] Tear strength: According to GB / T 15231.2-2019 "Metallic Coatings Part 2: Test Methods" and GB / T29906-2013 "Materials for Molded Polystyrene Board Thin Plaster Exterior Wall Insulation System", standard specimens were prepared according to the wall composite materials of Examples 1-3 and Comparative Examples 1-3. Five parallel specimens were prepared for each group of samples. The specimen size was a cube of 150mm×50mm×20mm. A 50mm long pre-cut was cut in the middle of the specimen. After molding, curing was completed according to the corresponding curing process. The two ends of the standard specimen were fixed in the upper and lower tear fixtures of the universal testing machine, ensuring that the pre-cut of the specimen was aligned with the center of the fixture and that the specimen was under tension. The loading rate was set to 50mm / min. The testing machine was started and the load was uniformly applied until the specimen was completely torn. The maximum load during the tearing process (unit: N) was recorded. The tear strength was calculated according to the formula:

[0103] ;

[0104] f t F represents tear strength (unit: N / mm). t b is the maximum tear force (unit: N), and b is the effective width of the specimen (unit: mm).

[0105] Figure 2 The figures show the mechanical properties of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3 of this invention. As shown in the figures, the compressive strength and tear strength of the wall composite materials prepared in Examples 1-3 of this invention are significantly improved. In this invention, the synthesis of phenolic resin under the modification of organosilicon polymer can improve the mechanical properties of phenolic resin. At the same time, the SiO2 aerogel composite rock wool fiber modified by phosphonate not only has excellent flame retardant properties, but also improves the interfacial bonding ability between it and phenolic resin, thereby improving the comprehensive mechanical properties of the wall composite material.

[0106] Experimental Example 3

[0107] This experiment presents a thermodynamic analysis of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3. Thermogravimetric analyzer was used to analyze the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3, and the mass change curve of the samples with temperature was recorded.

[0108] Figure 3The figure shows the thermogravimetric curves of the wall composite materials prepared in Examples 1-3 and Comparative Examples 1-3 of this invention. As shown in the figure, the initial degradation temperature of the wall composite materials prepared in Examples 1-3 is slightly higher than that of the wall composite materials prepared in Comparative Examples 1-3. At the same time, the residue rate of the wall composite materials prepared in Examples 1-3 is above 66%, while the residue rate of the wall composite materials prepared in Comparative Examples 1-3 is significantly lower than that of the examples. This indicates that the wall composite materials prepared in this invention can form a heat insulation layer during pyrolysis, effectively blocking the transfer of heat, and have considerable flame retardant properties and good thermal stability.

[0109] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

[0110] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention. The actual application is not limited to this. In conclusion, if those skilled in the art are inspired by this description and design similar methods and embodiments without departing from the spirit of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A fire resistant thermal insulation wall composite material, characterized by: The wall composite material comprises the following components in parts by weight: 55-65 parts fly ash, 16-24 parts desulfurized gypsum, 5-10 parts reinforcing rock wool fiber, 13-20 parts cement, 4-7 parts lime, 7-13 parts modified phenolic resin, 0.2-0.5 parts curing agent, 3-6 parts hollow glass microspheres, and 34-40 parts water; the raw materials for preparing the modified phenolic resin comprise the following components in parts by weight: 6.8 parts bis[3-(triethoxysilane)]propylamine, 3.0-3.5 parts epichlorohydrin, 4.5-5.0 parts phenol, and 1.5-2 parts formaldehyde; The raw materials for preparing the reinforced rock wool fiber include the following components in parts by weight: 8-12 parts activated rock wool fiber, 1.5 parts N-phosphorylated siloxane, and 4.0-9.5 parts tetraethoxysilane; The preparation method of the modified phenolic resin specifically includes the following steps: S1. Dissolve bis[3-(triethoxysilane)]propylamine in DMSO, purge with flowing nitrogen, add triethylamine, stir, and add epichlorohydrin solution dropwise. After the addition is complete, carry out the first-order reaction. After the reaction is complete, add catalyst, mix well, and raise the reaction temperature to carry out the second-order reaction. After the reaction is complete, add deionized water to dilute, add ethyl acetate for extraction, separate the organic phase, dry with anhydrous magnesium sulfate, and concentrate under reduced pressure to obtain organosilicon polymer. S2. Place phenol and formaldehyde in a flask, adjust the pH to 8.5-9.0, carry out a pre-crosslinking reaction, add the organosilicon polymer prepared in step S1, carry out a crosslinking condensation reaction, remove excess reaction solvent by rotary evaporation, and obtain modified phenolic resin. The method for preparing the reinforced rock wool fiber specifically includes the following steps: S3. Rock wool fibers are immersed in NaOH aqueous solution. After stirring to completely disperse the rock wool fibers in NaOH aqueous solution, the temperature is raised to carry out the alkaline treatment reaction. After the reaction is completed, the fibers are washed until neutral and dried to obtain activated rock wool fibers. S4. Dissolve γ-aminopropyltriethoxysilane in anhydrous DCM. Under ice-water bath conditions, slowly add phosphorus oxychloride. After the addition is complete, continue stirring and raise the temperature to carry out the condensation reaction. After the reaction is complete, add anhydrous ethanol to passivate P-Cl. Add deionized water and stir. Let stand for separation. Take the organic phase, wash it, dry it to remove water, concentrate it under reduced pressure, and obtain N-phosphorylated siloxane. S5. Dissolve the N-phosphorylated siloxane and tetraethoxysilane prepared in step S4 in anhydrous ethanol, place them in an ice-water bath, add deionized water, adjust the pH to 2-4, stir until the reaction system is homogeneous, add ammonia to adjust the pH of the reaction system to 6.0-6.5, raise the temperature to carry out the condensation reaction, after the reaction is completed, add the activated rock wool fiber prepared in step S3, vacuum to fully impregnate the activated rock wool fiber, let it stand and age, replace the solvent with anhydrous ethanol and anhydrous acetone in sequence, and perform supercritical CO2 drying to obtain reinforced rock wool fiber.

2. The fireproof and heat-insulating wall composite material according to claim 1, characterized in that: In step S1, the amount of triethylamine added is 0.5-1% of the mass of bis[3-(triethoxysilane)]propylamine; The catalyst is added at a rate of 0.15%-0.25% of the mass of bis[3-(triethoxysilane)]propylamine; In step S1, the reaction temperature of the first-order reaction is 30-50℃ and the reaction time is 1-2h. The reaction temperature of the second-order reaction is 70-90℃ and the reaction time is 6-10h.

3. The fireproof and heat-insulating wall composite material according to claim 2, characterized in that: In step S2, the reaction temperature of the pre-crosslinking reaction is 60-80℃, and the reaction time of the pre-crosslinking reaction is 20-60 min; In step S2, the crosslinking condensation reaction is carried out at a temperature of 80-90℃ for 2-3 hours.

4. The fireproof and heat-insulating wall composite material according to claim 3, characterized in that: In step S3, the mass concentration of NaOH in the NaOH aqueous solution is 5%-10%; the reaction temperature of the alkali treatment reaction is 50-70℃; and the reaction time of the alkali treatment reaction is 0.5-2h.

5. The fireproof and heat-insulating wall composite material according to claim 4, characterized in that: In step S4, the mass concentration of γ-aminopropyltriethoxysilane in anhydrous DCM is 30-50 mg / mL; the mass ratio of γ-aminopropyltriethoxysilane to phosphorus oxychloride is 1.3-1.4:1; the reaction temperature of the condensation reaction is 20-30℃; and the reaction time of the condensation reaction is 3-4 h.

6. The fireproof and heat-insulating wall composite material according to claim 5, characterized in that: In step S5, the condensation reaction temperature is 20-30℃ and the reaction time is 40-60 min.

7. A method for preparing a fireproof and thermally insulated wall composite material according to any one of claims 1-6, characterized in that: Specifically, the following steps are included: ① Pour fly ash, desulfurized gypsum, cement, lime, and hollow glass microspheres into a twin-shaft mixer and mix at 60-80 rpm for 5-10 minutes to obtain inorganic dry material; ② Mix the modified phenolic resin and curing agent to obtain a premixed liquid. Slowly spray the premixed liquid into the inorganic dry material prepared in step ①. Stir at 120-150 rpm for 3-5 minutes. Then add the reinforcing rock wool fiber and water. Stir at 200-250 rpm for 8-12 minutes. Continue mixing until there are no dry powder lumps and no free water to obtain the premixed material. ③ Place the premixed material prepared in step ② into a mold, mold it at room temperature, and then cure it to obtain the wall composite material.

8. The method for preparing a fireproof and heat-insulating wall composite material according to claim 7, characterized in that: In step ③, the parameters for the maintenance treatment include: Low-temperature pre-curing: After molding, place in an environment of 20-25℃ and 60%-70% relative humidity for 6-8 hours; Medium temperature curing: In the curing box, cure at 40-45℃ for 4-6 hours, then raise the temperature to 55-60℃ and cure for 8-10 hours; Room temperature maintenance: 20-25℃ in a well-ventilated environment, maintain for 7-10 days, spray water daily to keep the surface moist.

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