Fiber-toughened super-strong sound-insulation modified gypsum board and preparation method thereof

Abstract

The invention relates to the technical field of building materials, and particularly discloses a fiber toughening type super-strong sound insulation modified gypsum board and a preparation method thereof.The fiber toughening type super-strong sound insulation modified gypsum board is prepared from alpha-semi-hydrated gypsum, ardealite, sound insulation aerogel, modified bamboo fibers, modified aramid fibers, rubber particles, gypsum whiskers and water; the preparation method comprises the steps that the modified aramid fiber, the modified bamboo fiber and the sound insulation aerogel are sequentially prepared, then all the components are evenly mixed, poured and molded, a porous framework of the sound insulation aerogel and the sound absorption particles cooperate to dissipate sound waves, sound absorption is enhanced by combining the rubber particles, a toughening network is formed by the modified bamboo fiber and the aramid fiber, and the strength is improved through bridging of the gypsum whiskers; hydrophobic pores in the aerogel block water vapor, and an external hydrophilic coating stabilizes the structure, so that the sound insulation performance is not attenuated in a humid environment, and collaborative optimization of light weight, high strength and ultra-strong sound insulation is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of building materials, and in particular to a fiber-reinforced super-strong sound-insulating modified gypsum board and a preparation method thereof. Background Art

[0002] In modern construction projects, soundproof gypsum board is widely used in various building scenarios due to its excellent comprehensive performance. It can be used as a partition wall between rooms on a building, effectively blocking the transmission of sound between rooms on a floor, creating a quiet living environment for residents. In the suspended ceiling projects of public buildings such as office buildings and hotels, it can not only meet the functional requirements of sound insulation and noise reduction, but also reduce the burden on the main structure of the building with a lighter weight. At the same time, soundproof gypsum board also plays an important role in the sound insulation of floor slabs, which can significantly reduce noise interference between floors. In addition, in places with strict requirements on the acoustic environment, such as concert halls, studios, and hospital wards, soundproof gypsum board is an indispensable building material. Its light weight, high strength and excellent sound insulation performance can accurately meet the high requirements of the acoustic environment in these special scenarios.

[0003] In response to the aforementioned application requirements for superior sound insulation, the prior art proposes a gypsum board with superior sound insulation. This gypsum board is composed of modified starch, a retarder, a water reducer, an air entraining agent, modified graphene oxide, magnesium-aluminum hydrotalcite, and a residual amount of desulfurized gypsum powder. The modified starch is an aqueous emulsion of silicone-modified starch, and the modified graphene oxide is silane-modified graphene oxide. The preparation method involves first dehydrating the gypsum powder to convert it into β-type building gypsum, then adding water and stirring it into a gypsum slurry. The modified graphene oxide and modified starch are then added and aged, and then mixed with the remaining raw materials to form a blank. Finally, the gypsum board is formed through roller forming, coagulation and hardening, cutting, and drying. This technology enhances the gypsum board's sound absorption by adding the layered magnesium-aluminum hydrotalcite and utilizing the silicone-modified starch to react with the desulfurized gypsum powder to form a membrane-like structure based on the silane-modified graphene oxide, thereby achieving superior sound insulation.

[0004] Although the gypsum board of the prior art enhances the sound insulation effect by adding magnesium-aluminum hydrotalcite and forming a membrane structure, there are still limitations in the sound insulation performance in actual applications. Specifically, the layered structure of magnesium-aluminum hydrotalcite has limited sound absorption capacity. At the same time, the stability of the membrane structure formed is limited. During long-term use, the sound insulation performance may be attenuated due to environmental factors. In addition, the prior art lacks an effective fiber reinforcement system, and the mechanical properties and sound insulation performance of the gypsum board cannot be well synergistically optimized. Summary of the Invention

[0005] In view of the technical defects existing in the background technology, the present invention proposes a lightweight, high-strength, waterproof gypsum board and a preparation method thereof, which solves the above technical problems and meets practical needs. The specific technical solution is as follows: A fiber-reinforced, super-strong sound-insulating modified gypsum board comprises the following components, measured by weight: 70-100 parts of α-hemihydrate gypsum, 30-40 parts of phosphogypsum, 10-20 parts of sound-insulating aerogel, 5-10 parts of modified bamboo fiber, 4-6 parts of modified aramid fiber, 5-7 parts of rubber particles, 3-5 parts of gypsum whiskers, and 20-60 parts of water.

[0006] The sound-insulating aerogel is composed of a porous skeleton structure composed of reduced graphene oxide and carbonized nanocellulose fibers interwoven together, and sound-absorbing particles embedded in the porous skeleton structure. The internal pore surface of the sound-insulating aerogel is hydrophobic, and the outer surface of the sound-insulating aerogel is hydrophilic and combined with a polyethyleneimine coating.

[0007] As a further technical solution of the present invention, the sound-absorbing particles are any one or more of sepiolite and vermiculite, the sepiolite fiber length is 1-5 μm, and the vermiculite particle size is 20-50 μm.

[0008] As a further technical solution of the present invention, the modified bamboo fiber is prepared by modifying bamboo fiber with a polycarboxyl organic acid and then coating the surface with a PVA material. The diameter of the bamboo fiber is 200-300 μm and the length is 3-4 mm. The thickness of the coated PVA material is 20-50 μm. The polycarboxyl organic acid is any one or more of citric acid, tartaric acid, and succinic acid.

[0009] As a further technical solution of the present invention, the rubber particles are styrene-butadiene rubber with a particle size of 3 mm, and the gypsum whiskers are titanate gypsum whiskers with an aspect ratio greater than 20.

[0010] A method for preparing a fiber-reinforced, super-strong sound-insulating modified gypsum board comprises the following steps: S1. preparing modified aramid fiber; Aramid fibers with a diameter of 8-12 μm and a length of 2-4 mm were free of surface impurities, placed in a vacuum drying oven, and dried at 60° C. for 2 h. The dried aramid fibers were evenly spread on a sample rack in a plasma treatment chamber of a radio frequency plasma treatment system. The radio frequency power supply was turned on, the power was set to 100 W, and the treatment time was 5 min. After the treatment, the fibers were taken out and immediately ultrasonically cleaned in deionized water for 1-2 min. Subsequently, the fibers were vacuum dried at 60° C. for 30 min to obtain modified aramid fibers. S2, preparing modified bamboo fiber; The bamboo fiber is treated with a polycarboxyl organic acid solution under reflux at 90°C for 4 hours, and then the bamboo fiber is taken out, washed, immersed in a PVA sol, heated and immersed for 1-2 hours, filtered and separated, and dried at 60°C to form a PVA coating layer; S3, preparing sound insulation aerogel; The sound-absorbing particles were added to the fluorosilane solution and ultrasonically dispersed for 30 minutes. The mixture was stirred at 60°C for 2 hours, and then centrifuged, washed with ethanol three times, and dried at 80°C to obtain hydrophobic sound-absorbing particles. The hydrophobic sound-absorbing particles were added to a 2wt% nanocellulose aqueous suspension, 0.5wt% glutaraldehyde was added, and the mixture was stirred at 60°C for 1 hour. The mixture was then centrifuged to remove bubbles to obtain a nanocellulose-sound-absorbing particle suspension. The nanocellulose-sound-absorbing particle suspension was mixed with a graphene dispersion at a volume ratio of 2:1, magnetically stirred for 2 hours, and allowed to stand for defoaming for 30 minutes to obtain a wet gel. The wet gel was freeze-dried and crushed to 0.05-0.2 mm to obtain a gel intermediate 1. The gel intermediate 1 was placed in a tubular furnace for H2 / Ar high-temperature reduction to obtain a gel intermediate 2. The gel intermediate 2 was placed in a sealed container and evacuated, and 1.0 vol% PFDTES / ethanol solution, slowly restore to normal pressure, soak for 10 minutes, take out, cure at 80℃ for 2 hours, then treat with oxygen plasma, spray with 0.1wt% polyethyleneimine aqueous solution, and dry at 60℃ for 1 hour to obtain sound insulation aerogel.

[0011] S4, sound insulation modified gypsum board; 100 parts of α-hemihydrate gypsum, 40 parts of phosphogypsum, 20 parts of sound insulation aerogel, 10 parts of modified bamboo fiber, 6 parts of modified aramid fiber, 5 parts of rubber particles, 5 parts of gypsum whiskers, 0.8 parts of lithium magnesium silicate thickener, and 30 parts of water are mixed in a blender to obtain a slurry, which is then injected into a mold for casting to obtain a sound insulation modified gypsum board.

[0012] As a further technical solution of the present invention, in step S1, the equipment preparation method of the radio frequency plasma treatment system before treating the aramid fiber is as follows: the reaction chamber of the radio frequency plasma treatment system is evacuated to a vacuum degree of ≤10 -3 Pa, introduce high-purity Ar gas, adjust the gas flow rate to 50-100 sccm, and maintain the chamber pressure at 10-30 Pa.

[0013] As a further technical solution of the present invention, in step S2, the concentration of the polycarboxyl organic acid solution is 3.5-5wt%, the solid-liquid ratio of the bamboo fiber to the polycarboxyl organic acid solution is 1:10, and the concentration of PVA in the sol of the PVA material is 8-10wt%.

[0014] As a further technical solution of the present invention, in step S3, the ratio of the sound-absorbing particles to the fluorosilane solution is 10:1 (w / w), and the fluorosilane solution is a 1 vol% PFDTES-ethanol solution.

[0015] As a further technical solution of the present invention, in step S3, the freeze-drying method is: pre-freeze at -20°C for 2 hours, then take out, quench with liquid nitrogen for 10 minutes, and freeze-dry in a freeze dryer at a cold trap temperature of -50°C and a vacuum degree of 10 Pa for 48 hours.

[0016] As a further technical solution of the present invention, in step S3, the method for placing the gel intermediate in a tubular furnace for H2 / Ar high-temperature reduction is as follows: the gel intermediate is placed in a tubular furnace, and an H2 / Ar mixed gas is introduced into the tubular furnace, wherein the H2 content in the H2 / Ar mixed gas is 5 vol%, and a gradient temperature increase is adopted. In the first stage, the temperature is increased from 25°C to 300°C at a heating rate of 2°C / min, and the temperature is kept for 1 hour. In the second stage, the temperature is increased from 300°C to 500°C at a heating rate of 5°C / min, and the temperature is kept for 2 hours.

[0017] The beneficial effects of the present invention are: The sound-insulating aerogel uses a porous skeleton composed of reduced graphene oxide / carbonized nanocellulose as the main body for sound wave dissipation. It is embedded with hydrophobic sound-absorbing particles inside to form a multi-level sound-absorbing structure. Combined with rubber particles, it can effectively absorb noise. Modified bamboo fiber and modified aramid fiber form a reinforced network, which, combined with the bridging effect of gypsum whiskers and the stress dispersion of styrene-butadiene rubber particles, effectively improves the bending strength and impact resistance. The internal pores of the sound-insulating aerogel are treated with fluorosilane hydrophobicity, and the external hydrophilic coating is combined with polyethyleneimine cross-linking to block the intrusion of water vapor and ensure that the sound insulation performance is not attenuated in a humid environment. DETAILED DESCRIPTION

[0018] The following describes the implementation of the present invention in conjunction with relevant embodiments. The implementation of the present invention is not limited to the following embodiments, and the present invention relates to relevant necessary components in this technical field and should be regarded as a well-known technology in this technical field, which can be known and mastered by technical personnel in this technical field.

[0019] A fiber-reinforced, super-strong sound-insulating modified gypsum board comprises the following components, measured by weight: 70-100 parts of α-hemihydrate gypsum, 30-40 parts of phosphogypsum, 10-20 parts of sound-insulating aerogel, 5-10 parts of modified bamboo fiber, 4-6 parts of modified aramid fiber, 5-7 parts of rubber particles, 3-5 parts of gypsum whiskers, and 20-60 parts of water.

[0020] The sound-insulating aerogel is composed of a porous skeleton structure composed of reduced graphene oxide and carbonized nanocellulose fibers interwoven together, and sound-absorbing particles embedded in the porous skeleton structure. The internal pore surface of the sound-insulating aerogel is hydrophobic, and the outer surface of the sound-insulating aerogel is hydrophilic and combined with a polyethyleneimine coating.

[0021] The composition formula of the present invention constructs a multi-level sound insulation and reinforcement system by introducing sound insulation aerogel, modified fibers and functional particles, which significantly improves the comprehensive performance of gypsum board compared with the existing technology. Among them, the sound insulation aerogel is a porous skeleton structure formed by interweaving reduced graphene oxide and carbonized nanocellulose, and sound-absorbing particles such as sepiolite or vermiculite are embedded inside. This structural design can achieve efficient dissipation of sound waves in different frequency bands through the friction loss of the porous medium, the resonant sound absorption of the sound-absorbing particles and the sound wave scattering of the skeleton network, effectively solving the problem of limited sound absorption capacity of the magnesium-aluminum hydrotalcite layered structure in the existing technology.

[0022] After surface treatment, the modified bamboo fiber and modified aramid fiber have significantly enhanced interfacial bonding with the gypsum matrix. The two fibers are interwoven to form a three-dimensional reinforced network. At the same time, gypsum whiskers play a bridging role, and styrene-butadiene rubber particles disperse stress through elastic deformation. This multi-scale reinforcement system works synergistically to significantly improve the flexural strength and impact resistance of the gypsum board, making up for the defects of the existing technology in lacking an effective fiber reinforcement system and insufficient mechanical properties.

[0023] In addition, the internal pores of the sound-insulating aerogel are hydrophobized with fluorosilane, and the outer surface is bonded with a polyethyleneimine hydrophilic coating. This special structure, which is hydrophobic inside and hydrophilic outside, can not only prevent water vapor from invading the internal pores and affecting the sound absorption performance, but also can be tightly combined with the gypsum matrix through the hydrophilic coating on the outer surface, avoiding the problem of insufficient stability of the membrane structure due to environmental factors during long-term use, and ensuring the durability of the sound insulation performance of the gypsum board in a humid environment.

[0024] α-hemihydrate gypsum and phosphogypsum constitute a high-strength matrix, sound insulation aerogel and rubber particles synergistically improve the sound insulation effect, modified fibers and gypsum whiskers enhance the mechanical properties. Through reasonable proportions and functional complementarity, each component achieves synergistic optimization of sound insulation performance, mechanical strength and waterproof durability, effectively solving the technical problems of sound insulation performance attenuation and difficulty in balancing mechanical properties and sound insulation performance in existing technologies.

[0025] As one of the preferred embodiments of the present invention, the sound-absorbing particles are any one or more of sepiolite and vermiculite, the sepiolite fiber length is 1-5 μm, and the vermiculite particle size is 20-50 μm.

[0026] Specifically, the sound-absorbing particles are preferably sepiolite, and the fiber length of the sepiolite is 5 μm.

[0027] The short fiber structure of sepiolite and the appropriate particle size of vermiculite can be well embedded in the porous skeleton of the sound-insulating aerogel, forming a multi-level sound-absorbing structure. When sound waves are transmitted, the sepiolite fibers and vermiculite particles can dissipate sound energy through friction, resonance, etc., thereby improving the absorption effect of sound waves in different frequency bands. At the same time, the sound-absorbing particles of this size match well with the porous skeleton, and the structural stability and sound-absorbing performance of the aerogel will not be affected by particles that are too large or too small, thereby effectively enhancing the sound insulation ability of the gypsum board.

[0028] As one of the preferred embodiments of the present invention, the modified bamboo fiber is prepared by modifying bamboo fiber with a polycarboxyl organic acid and then coating the surface with a PVA material. The diameter of the bamboo fiber is 200-300 μm and the length is 3-4 mm. The thickness of the coated PVA material is 20-50 μm. The polycarboxyl organic acid is any one or more of citric acid, tartaric acid, and succinic acid.

[0029] Specifically, the diameter of the bamboo fiber is preferably 300 μm, the length is preferably 4 mm, the thickness of the coated PVA material is 50 μm, and the polycarboxyl organic acid is preferably succinic acid.

[0030] The modified bamboo fiber in the present invention is synergistically modified with polycarboxyl organic acid and PVA, thereby improving the mechanical properties of the gypsum board. The hydroxyl groups of the polycarboxyl organic acid (such as succinic acid) react with the hydroxyl groups on the surface of the bamboo fiber through esterification, and the other part is esterified with PVA, which not only improves the flexibility of the bamboo fiber but also enhances its interfacial compatibility with the PVA coating layer and the gypsum matrix through chemical bonding. The modified bamboo fiber is uniformly dispersed in the gypsum slurry and interwoven into a three-dimensional network, effectively bearing the load and inhibiting crack propagation. The PVA coating layer not only protects the bamboo fiber from erosion by the alkaline environment, but also forms a "bridging" structure with the polycarboxyl organic acid through esterification reaction, further strengthening the bonding between the fiber and the matrix, so that the modified bamboo fiber, modified aramid fiber, and gypsum whiskers synergistically construct a reinforcement system, significantly improving the flexural strength and impact resistance of the gypsum board, and solving the problem of insufficient mechanical properties in the prior art.

[0031] As one of the preferred embodiments of the present invention, the rubber particles are styrene-butadiene rubber with a particle size of 3 mm, and the gypsum whiskers are titanate gypsum whiskers with an aspect ratio greater than 20.

[0032] In this invention, 3mm-sized styrene-butadiene rubber particles and titanate-modified gypsum whiskers with an aspect ratio greater than 20 synergistically enhance mechanical properties. The styrene-butadiene rubber, through its elastic deformation, disperses external stress, absorbs impact energy, and improves the impact resistance of the gypsum board. The 3mm particle size ensures uniform distribution within the matrix and avoids excessive weakening of the matrix's continuity. The high aspect ratio of the titanate-modified gypsum whiskers forms a bridging network within the gypsum matrix, enhancing internal bonding. The titanate coupling agent on their surface improves interfacial compatibility with the gypsum, reduces stress concentration, and enhances flexural strength and toughness. Together with the modified fibers, these two components form a multi-scale reinforcement system, achieving synergistic optimization of mechanical properties.

[0033] A method for preparing a fiber-reinforced, super-strong sound-insulating modified gypsum board comprises the following steps: S1. preparing modified aramid fiber; Aramid fibers with a diameter of 8-12 μm and a length of 2-4 mm were free of surface impurities, placed in a vacuum drying oven, and dried at 60° C. for 2 h. The dried aramid fibers were evenly spread on a sample rack in a plasma treatment chamber of a radio frequency plasma treatment system. The radio frequency power supply was turned on, the power was set to 100 W, and the treatment time was 5 min. After the treatment, the fibers were taken out and immediately ultrasonically cleaned in deionized water for 1-2 min. Subsequently, the fibers were vacuum dried at 60° C. for 30 min to obtain modified aramid fibers. S2, preparing modified bamboo fiber; The bamboo fiber is treated with a polycarboxyl organic acid solution under reflux at 90°C for 4 hours, and then the bamboo fiber is taken out, washed, immersed in a PVA sol, heated and immersed for 1-2 hours, filtered and separated, and dried at 60°C to form a PVA coating layer; S3, preparing sound insulation aerogel; The sound-absorbing particles were added to the fluorosilane solution and ultrasonically dispersed for 30 minutes. The mixture was stirred at 60°C for 2 hours, and then centrifuged, washed with ethanol three times, and dried at 80°C to obtain hydrophobic sound-absorbing particles. The hydrophobic sound-absorbing particles were added to a 2wt% nanocellulose aqueous suspension, 0.5wt% glutaraldehyde was added, and the mixture was stirred at 60°C for 1 hour. The mixture was then centrifuged to remove bubbles to obtain a nanocellulose-sound-absorbing particle suspension. The nanocellulose-sound-absorbing particle suspension was mixed with a graphene dispersion at a volume ratio of 2:1, magnetically stirred for 2 hours, and allowed to stand for defoaming for 30 minutes to obtain a wet gel. The wet gel was freeze-dried and crushed to 0.05-0.2 mm to obtain a gel intermediate 1. The gel intermediate 1 was placed in a tubular furnace for H2 / Ar high-temperature reduction to obtain a gel intermediate 2. The gel intermediate 2 was placed in a sealed container and evacuated, and 1.0 vol% PFDTES / ethanol solution, slowly restore to normal pressure, soak for 10 minutes, take out, cure at 80℃ for 2 hours, then treat with oxygen plasma, spray with 0.1wt% polyethyleneimine aqueous solution, and dry at 60℃ for 1 hour to obtain sound insulation aerogel.

[0034] S4, sound insulation modified gypsum board; 100 parts of α-hemihydrate gypsum, 40 parts of phosphogypsum, 20 parts of sound insulation aerogel, 10 parts of modified bamboo fiber, 6 parts of modified aramid fiber, 5 parts of rubber particles, 5 parts of gypsum whiskers, 0.8 parts of lithium magnesium silicate thickener, and 30 parts of water are mixed in a blender to obtain a slurry, which is then injected into a mold for casting to obtain a sound insulation modified gypsum board.

[0035] The preparation method of the present invention achieves the synergistic optimization of the performance of each component and a significant improvement in interface compatibility through multi-dimensional modification treatment and precise process control. In the preparation of modified aramid fibers, radio frequency plasma treatment is used to remove impurities on the fiber surface through high-energy particle bombardment and introduce polar groups, thereby enhancing the interfacial bonding between the fiber and the gypsum matrix, thereby effectively improving the mechanical strength of the gypsum board. When preparing modified bamboo fibers, polycarboxyl organic acids are esterified with the hydroxyl groups on the surface of the bamboo fibers and simultaneously undergo an esterification reaction with PVA, which not only improves the flexibility of the bamboo fibers, but also forms a "fiber-PVA-gypsum" bridging structure through chemical bonding, thereby enhancing interfacial compatibility and load transfer efficiency.

[0036] During the preparation of the sound-insulating aerogel, fluorosilane treatment renders the sound-absorbing particles hydrophobic. After embedding them into a porous nanocellulose-graphene framework, freeze-drying preserves the three-dimensional porous structure, ensuring sound wave dissipation channels. High-temperature H2 / Ar reduction enhances the conductivity and structural stability of the graphene network. Oxygen plasma combined with polyethyleneimine treatment renders the aerogel's outer surface hydrophilic, forming a "hydrophobic inside and hydrophilic outside" structure that not only blocks water vapor from invading internal pores but also tightly bonds with the gypsum matrix, ensuring long-lasting sound insulation. Through surface modification, structural regulation, and interface optimization of each component, the overall preparation process achieves efficient sound absorption for the sound-insulating aerogel, mechanical strengthening of the fiber-reinforced system, and stable construction of a waterproof structure. The resulting gypsum board combines superior sound insulation, lightweight, high strength, and waterproof and durable properties.

[0037] As one of the preferred embodiments of the present invention, in step S1, the equipment preparation method of the radio frequency plasma treatment system before treating the aramid fiber is as follows: the reaction chamber of the radio frequency plasma treatment system is evacuated to a vacuum degree of ≤10 -3 Pa, introduce high-purity Ar gas, adjust the gas flow rate to 50-100 sccm, and maintain the chamber pressure at 10 -3 0Pa.

[0038] Equipment preparation steps: By controlling the vacuum degree, argon flow and pressure of the reaction chamber, a stable and efficient environment is created for RF plasma treatment of aramid fibers. The chamber is evacuated to a vacuum degree of ≤10 -3 Pa can exclude air and impurities to prevent contamination during fiber processing; introducing high-purity Ar gas and maintaining a flow rate of 50-100sccm and a pressure of 10-30Pa can form a uniform and stable plasma atmosphere, allowing high-energy particles to evenly bombard the surface of the aramid fiber, effectively removing impurities and introducing polar groups, thereby significantly improving the interfacial compatibility between the fiber and the gypsum matrix, laying the foundation for the subsequent enhancement of the mechanical properties of the gypsum board.

[0039] As one of the preferred embodiments of the present invention, in step S2, the concentration of the polycarboxyl organic acid solution is 3.5-5wt%, the solid-liquid ratio of the bamboo fiber to the polycarboxyl organic acid solution is 1:10, and the concentration of PVA in the sol of the PVA material is 8-10wt%.

[0040] Specifically, the concentration of the polycarboxyl organic acid solution is 3.5 wt %, and the concentration of PVA in the sol of the PVA material is 8 wt %.

[0041] The esterification and connection of polycarboxyl organic acids effectively improves the uniformity and effectiveness of bamboo fiber modification and PVA coating. A 3.5wt% polycarboxyl organic acid solution concentration not only allows the carboxyl groups to fully esterify with the hydroxyl groups on the bamboo fiber surface, but also avoids excessive acidification and structural damage caused by excessive concentration. A PVA sol concentration of 8wt% forms a coating solution with appropriate viscosity, ensuring a 50μm uniform and continuous coating layer on the bamboo fiber surface. At this concentration, the hydroxyl groups on the PVA molecular chain can fully esterify with the remaining carboxyl groups of the polycarboxyl organic acid. Through the chemical bonding of "bamboo fiber-polycarboxyl organic acid-PVA", a strong interfacial bonding bridging structure is constructed, which not only improves the flexibility of the bamboo fiber to inhibit cracking of the gypsum matrix, but also strengthens the load transfer efficiency between the fiber and the gypsum matrix, thereby effectively improving the flexural strength and impact resistance of the gypsum board.

[0042] As one of the preferred embodiments of the present invention, in step S3, the ratio of the sound-absorbing particles to the fluorosilane solution is 10:1 (w / w), and the fluorosilane solution is a 1 vol% PFDTES-ethanol solution.

[0043] In step S3, the sound-absorbing particles are treated with a fluorosilane solution. This preparation principle is based on the interfacial modification mechanism of a silane coupling agent: after hydrolysis of fluorosilane (PFDTES) in an ethanol solvent, the silane groups undergo a condensation reaction with the hydroxyl groups on the particle surface, forming a covalently bonded hydrophobic modified layer. The fluorocarbon chains are oriented on the particle surface, significantly reducing the surface energy and imparting hydrophobicity to the particles. This hydrophobic modification prevents water vapor from penetrating the particles during subsequent preparation and use, preventing the pore structure from being filled with water and affecting the efficiency of sound wave dissipation. Furthermore, after the hydrophobized particles are embedded in the nanocellulose-graphene porous framework, they form a compatible interface with the hydrophobic graphene network, creating hydrophobic channels within the aerogel. This ensures efficient sound wave dissipation through friction and reflection within the porous structure. The external hydrophilic coating, in turn, tightly bonds to the gypsum matrix, achieving a "hydrophobic interior, hydrophilic exterior" structural design, ensuring the durability and stability of sound insulation performance.

[0044] As one of the preferred embodiments of the present invention, in step S3, the freeze-drying method is: pre-freezing at -20°C for 2 hours, then taking out, quenching with liquid nitrogen for 10 minutes, and placing in a freeze dryer for freeze drying at a cold trap temperature of -50°C and a vacuum degree of 10 Pa for 48 hours.

[0045] The freeze-drying method described above achieves precise maintenance of the porous structure of the sound-insulating aerogel in terms of preparation principle through the synergistic effect of step-by-step temperature control and a vacuum environment. Pre-freezing at -20°C causes the water in the material to form initial ice crystals. The rapid cooling with liquid nitrogen inhibits the excessive growth of ice crystals through an extremely fast cooling rate, preventing large-sized ice crystals from mechanically damaging the nanocellulose-graphene skeleton, thereby controlling the uniformity of pore size. The freeze-drying process using a -50°C cold trap combined with a vacuum of 10Pa allows the ice crystals to directly sublimate rather than vaporize from the liquid state, eliminating the compression and collapse of the porous network by the surface tension of liquid water, and completely preserving the interconnected three-dimensional pore structure within the aerogel. This structure provides an efficient dissipation channel for sound waves, optimizing sound insulation performance through air vibration friction within the pores and multiple reflections of sound waves. At the same time, it avoids the problems of skeleton shrinkage and pore closure caused by traditional drying methods, ensuring that the aerogel has both high specific surface area and stable acoustic properties.

[0046] As one of the preferred embodiments of the present invention, in step S3, the method for placing the gel intermediate in a tubular furnace for H2 / Ar high-temperature reduction is as follows: the gel intermediate is placed in a tubular furnace, and an H2 / Ar mixed gas is introduced into the tubular furnace, wherein the H2 content in the H2 / Ar mixed gas is 5 vol%, and a gradient temperature increase is adopted. In the first stage, the temperature is increased from 25°C to 300°C at a heating rate of 2°C / min, and the temperature is kept for 1 hour. In the second stage, the temperature is increased from 300°C to 500°C at a heating rate of 5°C / min, and the temperature is kept for 2 hours.

[0047] This high-temperature reduction treatment utilizes the reducing properties of H2 and the protective atmosphere of Ar to achieve structural optimization and performance control of the gel intermediate one in steps through a gradient temperature increase. In the H2 / Ar gas mixture, H2, as a reducing agent, can effectively remove oxygen-containing functional groups (such as hydroxyl groups and epoxy groups) on the graphene surface, restoring its conjugated π bond structure and significantly improving the conductivity and structural stability of the graphene network. The gradient temperature increase process avoids thermal stress damage to the material caused by sudden temperature increases. The low-temperature treatment in the first stage promotes the gradual removal of weakly bonded oxygen-containing groups, and the high-temperature insulation in the second stage further strengthens the π-π interaction between graphene layers, while promoting physical entanglement and chemical coupling at the interface between nanocellulose and graphene, forming a dense and stable three-dimensional porous skeleton. This skeleton structure not only provides an efficient channel for acoustic wave dissipation, but its enhanced conductivity and mechanical strength can also synergistically improve the overall performance of the aerogel.

[0048] Example 1 A method for preparing a fiber-reinforced, super-strong sound-insulating modified gypsum board comprises the following steps: S1. preparing modified aramid fiber; Aramid fibers with a diameter of 12 μm and a length of 4 mm were cleaned of surface impurities and placed in a vacuum drying oven for 2 h at 60 °C. The reaction chamber of the RF plasma treatment system was evacuated to a vacuum degree of ≤10-3 Pa, high-purity Ar gas was introduced at a flow rate of 100 sccm, maintaining the chamber pressure at 30 Pa. The dried aramid fiber was then evenly spread on the sample holder in the plasma treatment chamber. The RF power was turned on at 100 W and the treatment time was 5 minutes. After the treatment, the fiber was removed and immediately ultrasonically cleaned in deionized water for 1-2 minutes, followed by vacuum drying at 60°C for 30 minutes to obtain the modified aramid fiber.

[0049] S2, preparing modified bamboo fiber; Bamboo fibers with a diameter of 300 μm and a length of 4 mm were treated with a 3.5 wt% succinic acid solution at 90°C for 4 hours under reflux. The solid-to-liquid ratio of the bamboo fibers to the polycarboxylic organic acid solution was 1:10. The fibers were then removed, washed, and immersed in an 8 wt% PVA sol, heated and immersed for 1-2 hours. The fibers were separated by filtration and dried at 60°C to form a PVA coating.

[0050] S3, preparing sound insulation aerogel; 5μm-long sepiolite sound-absorbing particles were added to a 1 vol% PFDTES-ethanol solution at a mass ratio of 10:1. The particles were ultrasonically dispersed for 30 minutes, stirred at 60°C for 2 hours, centrifuged, washed three times with ethanol, and dried at 80°C to obtain hydrophobic sound-absorbing particles. The hydrophobic sound-absorbing particles were then added to a 2 wt% nanocellulose aqueous suspension, followed by 0.5 wt% glutaraldehyde. The mixture was stirred at 60°C for 1 hour, and then centrifuged to remove bubbles, resulting in a nanocellulose-sound-absorbing particle suspension. The nanocellulose-sound-absorbing particle suspension was then mixed with a graphene dispersion at a volume ratio of 2:1, magnetically stirred for 2 hours, and allowed to stand for 30 minutes to defoam, yielding a wet gel. The wet gel was pre-frozen at -20°C for 2 hours, then removed, quenched with liquid nitrogen for 10 minutes, and freeze-dried in a freeze dryer at -50°C and a vacuum of 10 Pa for 48 hours to obtain gel intermediate 1. Gel intermediate 1 was placed in a tubular furnace, which was then infused with a H2 / Ar mixture (5 vol%). A gradient temperature ramp was employed: the first stage: from 25°C to 300°C at a rate of 2°C / min, held for 1 hour; the second stage: from 300°C to 500°C at a rate of 5°C / min, held for 2 hours, yielding gel intermediate 2. Gel intermediate 2 was then placed in a sealed container, evacuated, and injected with a 1.0 vol% PFDTES / ethanol solution. The pressure was slowly restored to normal, and the container was immersed for 10 minutes before removal. The container was cured at 80°C for 2 hours, then treated with oxygen plasma, sprayed with a 0.1 wt% aqueous solution of polyethyleneimine, and dried at 60°C for 1 hour to yield the sound-insulating aerogel.

[0051] S4, sound insulation modified gypsum board; 100 parts of α-hemihydrate gypsum, 40 parts of phosphogypsum, 20 parts of sound insulation aerogel, 10 parts of modified bamboo fiber, 6 parts of modified aramid fiber, 5 parts of styrene-butadiene rubber particles with a particle size of 3 mm, 5 parts of titanate gypsum whiskers with an aspect ratio greater than 20, 0.8 parts of lithium magnesium silicate thickener, and 30 parts of water are mixed in a blender to obtain a slurry, which is then injected into a mold for casting to obtain a sound insulation modified gypsum board.

[0052] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the sound-insulating aerogel component is eliminated, and 20 parts of the sound-insulating aerogel in the formula are replaced by an equal amount of α-hemihydrate gypsum (i.e., the α-hemihydrate gypsum is increased to 120 parts), and the other components and preparation process remain unchanged.

[0053] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the modification treatment steps of the aramid fiber and the bamboo fiber are omitted (steps S1 and S2 are cancelled), 6 parts of the modified aramid fiber and 10 parts of the modified bamboo fiber are replaced with unmodified aramid fiber and bamboo fiber of the same specification, and the other components and preparation process remain unchanged.

[0054] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that the rubber particle component is eliminated, and 5 parts of styrene-butadiene rubber particles in the formula are replaced by phosphogypsum (i.e., the phosphogypsum is increased to 45 parts), and the other components and preparation process remain unchanged.

[0055] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that the gypsum whisker component is eliminated, and 5 parts of titanate gypsum whiskers in the formula are replaced by an equal amount of α-hemihydrate gypsum (i.e., α-hemihydrate gypsum is increased to 105 parts), and the other components and preparation process remain unchanged.

[0056] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that the preparation process of the sound-insulating aerogel is simplified, the hydrophobic treatment of the sound-absorbing particles (fluorosilane solution modification), the outer surface hydrophilic treatment (polyethyleneimine coating) and the oxygen plasma treatment steps in step S3 are omitted, and the other components and preparation processes remain unchanged.

[0057] Performance testing: The lightweight sound-insulating gypsum boards obtained in Example 1 and Comparative Examples 1-5 were tested in accordance with JGT169-2016 and GBJ88-85 Standard for Measurement of Sound Absorption Coefficient and Acoustic Impedance by Standing Wave Tube Method. The test data are shown in the following table:

[0058] By comparing and analyzing the performance test data of Example 1 and Comparative Examples 1-5, the following conclusions can be drawn: As a core functional component, the role of sound-insulating aerogel is reflected in its acoustic and mechanical properties. When this component is removed from Comparative Example 1, the sound absorption coefficient drops sharply from 0.55, 0.80, and 0.65 to 0.3, 0.4, and 0.3 in the 500Hz, 1000Hz, and 2000Hz frequency bands, respectively, a drop of more than 45%. This fully verifies the efficient dissipation of sound wave energy by its multi-layered structure composed of porous skeleton and sound-absorbing particles. At the same time, the compressive strength drops from 4.6 MPa to 4.2 MPa, the bending load multiple drops from 2.5 to 2.3, and the surface density is reduced to 9 kg / m², indicating that aerogel has a synergistic effect in lightweighting and matrix reinforcement. The softening coefficient drops from 0.81 to 0.75, further illustrating the key role of its hydrophobic-hydrophilic composite structure in waterproofing.

[0059] In Comparative Example 2, using unmodified fibers, the bending load multiple decreased significantly by 28% (from 2.5 to 1.8 times), and the impact resistance decreased by 43% (from 7 to 4 times). This is directly attributed to the enhanced fiber-matrix interface bonding achieved by the RF plasma treatment and PVA coating process. The three-dimensional network constructed by the modified fibers becomes the core skeleton for load transfer, and its failure leads to significant deterioration of mechanical properties. Notably, the sound absorption coefficient decreased only slightly (from 0.80 to 0.78 at 1000 Hz), indicating that the fiber network assists in sound wave scattering.

[0060] In Comparative Example 3, after removing the styrene-butadiene rubber particles, the impact resistance plummeted to 3 times (a 57% decrease), demonstrating the efficient absorption of impact energy through elastic deformation. Simultaneously, the 500Hz sound absorption coefficient dropped from 0.55 to 0.50, indicating the rubber particles' complementary effect on low-frequency sound absorption. In Comparative Example 4, removing the gypsum whiskers resulted in a 20% decrease in the bending load multiple (from 2.5 to 2), and the impact resistance dropped to 5 times, confirming the bridging toughening effect of the high-aspect-ratio whiskers. The titanate modification of their surface further optimized the stress transfer pathway.

[0061] After simplified hydrophobic / hydrophilic treatment in Comparative Example 5, the softening coefficient decreased significantly by 14% (from 0.81 to 0.70), confirming that the dual barrier of internal fluorosilane hydrophobic treatment and external polyethyleneimine coating effectively blocks water vapor intrusion. While the sound absorption coefficient decreased only slightly (from 0.65 to 0.64 at 2000 Hz), the more pronounced attenuation trend at higher frequencies reveals the sensitivity of humidity to acoustic dissipation pathways, highlighting the importance of the integrated process in ensuring the stability of the porous structure.

[0062] Overall, the components form a synergistic optimization system through functional complementarity: the sound-insulating aerogel and rubber particles are combined to cover the broadband sound absorption needs; the modified bamboo fiber, modified aramid fiber, gypsum whiskers and rubber particles form a "three-level mechanical reinforcement structure", which respectively undertake the functions of main network reinforcement, matrix bridging toughening and impact energy dispersion; and the aerogel's internal hydrophobic and external hydrophilic structure builds a double barrier for environmental stability.

[0063] The above description is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A fiber-reinforced super-strong sound-insulating modified gypsum board, characterized in that: The invention comprises the following components in parts by weight: 70-100 parts of α-hemihydrate gypsum, 30-40 parts of phosphogypsum, 10-20 parts of sound insulation aerogel, 5-10 parts of modified bamboo fiber, 4-6 parts of modified aramid fiber, 5-7 parts of rubber particles, 3-5 parts of gypsum whiskers, and 20-60 parts of water; The sound-insulating aerogel is composed of a porous skeleton structure composed of reduced graphene oxide and carbonized nanocellulose fibers interwoven together, and sound-absorbing particles embedded in the porous skeleton structure. The internal pore surface of the sound-insulating aerogel is hydrophobic, and the outer surface of the sound-insulating aerogel is hydrophilic and combined with a polyethyleneimine coating.

2. The fiber-reinforced super-strong sound-insulating modified gypsum board according to claim 1, characterized in that: The sound-absorbing particles are any one or more of sepiolite and vermiculite. The sepiolite fiber length is 1-5 μm, and the vermiculite particle size is 20-50 μm.

3. The fiber-reinforced super-strong sound-insulating modified gypsum board according to claim 1, characterized in that: The modified bamboo fiber is prepared by modifying bamboo fiber with a polycarboxyl organic acid and then coating the surface with a PVA material. The diameter of the bamboo fiber is 200-300 μm and the length is 3-4 mm. The thickness of the coated PVA material is 20-50 μm. The polycarboxyl organic acid is any one or more of citric acid, tartaric acid, and succinic acid.

4. The fiber-reinforced super-strong sound-insulating modified gypsum board according to claim 1, characterized in that: The rubber particles are styrene-butadiene rubber with a particle size of 3 mm, and the gypsum whiskers are titanate gypsum whiskers with an aspect ratio greater than 20.

5. A method for preparing a fiber-reinforced, super-strong sound-insulating modified gypsum board according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. preparing modified aramid fiber; Aramid fibers with a diameter of 8-12 μm and a length of 2-4 mm were free of surface impurities, placed in a vacuum drying oven, and dried at 60° C. for 2 h. The dried aramid fibers were evenly spread on a sample rack in a plasma treatment chamber of a radio frequency plasma treatment system. The radio frequency power supply was turned on, the power was set to 100 W, and the treatment time was 5 min. After the treatment, the fibers were taken out and immediately ultrasonically cleaned in deionized water for 1-2 min. Subsequently, the fibers were vacuum dried at 60° C. for 30 min to obtain modified aramid fibers. S2, preparing modified bamboo fiber; The bamboo fiber is treated with a polycarboxyl organic acid solution under reflux at 90°C for 4 hours, and then the bamboo fiber is taken out, washed, immersed in a PVA sol, heated and immersed for 1-2 hours, filtered and separated, and dried at 60°C to form a PVA coating layer; S3, preparing sound insulation aerogel; The sound-absorbing particles were added to the fluorosilane solution and ultrasonically dispersed for 30 minutes. The mixture was stirred at 60°C for 2 hours, and then centrifuged, washed with ethanol three times, and dried at 80°C to obtain hydrophobic sound-absorbing particles. The hydrophobic sound-absorbing particles were added to a 2wt% nanocellulose aqueous suspension, 0.5wt% glutaraldehyde was added, and the mixture was stirred at 60°C for 1 hour. The mixture was then centrifuged to remove bubbles to obtain a nanocellulose-sound-absorbing particle suspension. The nanocellulose-sound-absorbing particle suspension was mixed with a graphene dispersion at a volume ratio of 2:1, magnetically stirred for 2 hours, and allowed to stand for defoaming for 30 minutes to obtain a wet gel. The wet gel was freeze-dried and crushed to 0.05-0.2 mm to obtain a gel intermediate 1. The gel intermediate 1 was placed in a tubular furnace for H2 / Ar high-temperature reduction to obtain a gel intermediate 2. The gel intermediate 2 was placed in a sealed container and evacuated, and 1.0 vol% PFDTES / ethanol solution, slowly restore to normal pressure, soak for 10 minutes, take out, cure at 80℃ for 2 hours, then treat with oxygen plasma, spray with 0.1wt% polyethyleneimine aqueous solution, and dry at 60℃ for 1 hour to obtain sound insulation aerogel; S4, sound insulation modified gypsum board; 100 parts of α-hemihydrate gypsum, 40 parts of phosphogypsum, 20 parts of sound insulation aerogel, 10 parts of modified bamboo fiber, 6 parts of modified aramid fiber, 5 parts of rubber particles, 5 parts of gypsum whiskers, 0.8 parts of lithium magnesium silicate thickener, and 30 parts of water are mixed in a blender to obtain a slurry, which is then injected into a mold for casting to obtain a sound insulation modified gypsum board.

6. The method for preparing the fiber-reinforced super-strong sound-insulating modified gypsum board according to claim 5, characterized in that: In step S1, the equipment preparation method of the radio frequency plasma treatment system before treating the aramid fiber is as follows: the reaction chamber of the radio frequency plasma treatment system is evacuated to a vacuum degree of ≤10 -3 Pa, introduce high-purity Ar gas, adjust the gas flow rate to 50-100 sccm, and maintain the chamber pressure at 10-30 Pa.

7. The method for preparing the fiber-reinforced super-strong sound-insulating modified gypsum board according to claim 5, characterized in that: In step S2, the concentration of the polycarboxyl organic acid solution is 3.5-5wt%, the solid-liquid ratio of the bamboo fiber to the polycarboxyl organic acid solution is 1:10, and the concentration of PVA in the sol of the PVA material is 8-10wt%.

8. The method for preparing the fiber-reinforced super-strong sound-insulating modified gypsum board according to claim 5, characterized in that: In step S3, the ratio of the sound-absorbing particles to the fluorosilane solution is 10:1 (w / w), and the fluorosilane solution is a 1 vol% PFDTES-ethanol solution.

9. The method for preparing fiber-reinforced super-strong sound-insulating modified gypsum board according to claim 5, characterized in that: In step S3, the freeze-drying method is: pre-freeze at -20°C for 2 hours, then take out, quench with liquid nitrogen for 10 minutes, and freeze-dry in a freeze dryer at a cold trap temperature of -50°C and a vacuum degree of 10 Pa for 48 hours.

10. The method for preparing fiber-reinforced super-strong sound-insulating modified gypsum board according to claim 5, characterized in that: In step S3, the method for placing the gel intermediate in a tubular furnace for H2 / Ar high-temperature reduction is as follows: the gel intermediate is placed in a tubular furnace, and an H2 / Ar mixed gas is introduced into the tubular furnace, wherein the H2 content in the H2 / Ar mixed gas is 5 vol%, and a gradient temperature increase is adopted. In the first stage, the temperature is increased from 25°C to 300°C at a heating rate of 2°C / min, and the temperature is kept for 1 hour. In the second stage, the temperature is increased from 300°C to 500°C at a heating rate of 5°C / min, and the temperature is kept for 2 hours.

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