WO2023035709A1 - 一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法 - Google Patents

一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法 Download PDF

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WO2023035709A1
WO2023035709A1 PCT/CN2022/098361 CN2022098361W WO2023035709A1 WO 2023035709 A1 WO2023035709 A1 WO 2023035709A1 CN 2022098361 W CN2022098361 W CN 2022098361W WO 2023035709 A1 WO2023035709 A1 WO 2023035709A1
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fly ash
magnesium
absorbing material
porous sound
hydrophobic modified
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PCT/CN2022/098361
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English (en)
French (fr)
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程芳琴
方莉
周冬冬
何建宽
贾真真
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山西大学
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Publication of WO2023035709A1 publication Critical patent/WO2023035709A1/zh
Priority to US18/202,973 priority Critical patent/US20230295047A1/en

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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/30—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing magnesium cements or similar cements
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/10—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof by using foaming agents or by using mechanical means, e.g. adding preformed foam
    • C04B38/106—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof by using foaming agents or by using mechanical means, e.g. adding preformed foam by adding preformed foams
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
    • C04B41/46—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with organic materials
    • C04B41/49—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes
    • C04B41/4905—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes containing silicon
    • C04B41/4922—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes containing silicon applied to the substrate as monomers, i.e. as organosilanes RnSiX4-n, e.g. alkyltrialkoxysilane, dialkyldialkoxysilane
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/60—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only artificial stone
    • C04B41/61—Coating or impregnation
    • C04B41/62—Coating or impregnation with organic materials
    • C04B41/64—Compounds having one or more carbon-to-metal of carbon-to-silicon linkages
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00241—Physical properties of the materials not provided for elsewhere in C04B2111/00
    • C04B2111/00413—Materials having an inhomogeneous concentration of ingredients or irregular properties in different layers
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/20—Resistance against chemical, physical or biological attack
    • C04B2111/27—Water resistance, i.e. waterproof or water-repellent materials
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/52—Sound-insulating materials
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
    • C04B2201/20—Mortars, concrete or artificial stone characterised by specific physical values for the density
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
    • C04B2201/50—Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00—Technologies for solid waste management
    • Y02W30/50—Reuse, recycling or recovery technologies
    • Y02W30/91—Use of waste materials as fillers for mortars or concrete

Definitions

  • the invention relates to the field of sound absorption and noise reduction, in particular to a surface-hydrophobic modified magnesium-based fly ash porous sound-absorbing material and a preparation method thereof.
  • the commonly used methods to control noise are to set up sound barriers on both sides of the road, and to install sound-absorbing materials around the factory buildings.
  • the sound-absorbing sound barrier has the function of absorbing sound waves, and can improve the acoustic environment on both sides of the road at the same time.
  • Inorganic non-metallic porous materials such as rock wool, porous ceramics, foam cement, etc., are commonly used unit panel materials for sound-absorbing sound barriers due to their advantages of flame retardancy and good weather resistance.
  • rock wool and porous ceramics have excellent sound absorption performance
  • the production process of rock wool is seriously polluted, which endangers the health of workers during construction and causes environmental pollution during use.
  • the preparation process of porous ceramics is high in energy consumption, brittle, and relatively expensive. High; Although the cost of traditional foam cement is low, it is difficult to balance the mechanical and sound-absorbing properties at the same time. Therefore, it is urgent to develop a sound-absorbing material with light weight, high strength, excellent sound-absorbing performance, good weather resistance, low cost and environmental protection.
  • Patent CN207062795U discloses a cement-based sound-absorbing material.
  • the direct contact area between the porous absorbing structure inside the material and the sound wave is increased, and the average sound-absorbing performance of the prepared porous sound-absorbing material is The coefficient has increased by 6% ⁇ 30%.
  • the setting of sound absorption holes is helpful to improve the sound absorption performance, it will inevitably affect the mechanical strength of the material.
  • Patent CN110255987A discloses a cement-based foam sound-absorbing material, which is foamed by anionic surfactant and air-dried naturally to produce more pores, and the average sound absorption coefficient is increased by 10% to 30%, but air-drying may cause the material to lose water due to the surface If it is too fast and the hydration is not complete, there will be surface pulverization.
  • Patent CN108529887B discloses a method for preparing high-strength porous sound-absorbing materials using high-titanium blast furnace slowly cooled slag as the main raw material, but the average sound absorption coefficient of the prepared materials is only 0.28-0.49.
  • the present invention proposes a surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material and a preparation method thereof, the sound-absorbing material uses basic magnesium sulfate cement as a gelling agent, and uses fly ash as a mineral admixture , using physical foaming technology, a new type of light-weight, high-strength, good sound-absorbing performance and surface hydrophobic properties prepared by foaming machine foaming, foam and slurry mixing, pouring curing, surface hydrophobic modification sound-absorbing material.
  • the purpose of the present invention is to provide a surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material and its preparation method. High strength, surface hydrophobicity and good weather resistance.
  • a method for preparing a surface-hydrophobic modified magnesium-based fly ash porous sound-absorbing material comprising the following steps:
  • Step 1 mixing magnesium oxide, fly ash and fiber evenly to obtain a mixed dry material
  • Step 2 dissolving magnesium sulfate heptahydrate and additive in water, heating and dissolving to obtain magnesium sulfate solution containing additive;
  • Step 3 adding the mixed dry material obtained in step 1 to the magnesium sulfate solution containing admixture obtained in step 2, and stirring to obtain cement slurry;
  • Step 4 diluting the foaming agent with water, then using a foaming machine to prepare foam, and adding the foam to the cement paste obtained in step 3 by stirring at a low speed to obtain a foam paste;
  • Step 5 pour the foaming slurry obtained in step 4 into the mold, then cover with a layer of plastic wrap, and release the mold after curing in the air at room temperature for 1 day, and continue curing until the test age to obtain a magnesium-based fly ash porous material ;
  • Step 6 dripping a modifier around the magnesium-based fly ash porous material obtained in step 5, after sealing, carry out surface deposition modification under constant temperature conditions to obtain a modified material;
  • step 7 the modified material obtained in step 6 is fully cooled at room temperature and then taken out to obtain a surface-hydrophobic modified magnesium-based fly ash porous sound-absorbing material.
  • magnesia in the step 1 is light-burned magnesia, wherein the content of active magnesia is 55wt% ⁇ 70wt%, too high active content of magnesia will make the slurry coagulation rate too fast, resulting in its If the active content of magnesium oxide is too low, the coagulation rate of the slurry will be too slow, and the stability time of the foam will not match the coagulation time of the slurry, resulting in mold collapse.
  • the fly ash is 10% ⁇ 30% of the total mass of the mixed dry material.
  • the fly ash can reduce the material cost, but in the basic magnesium sulfate weak alkaline system, the pozzolanic activity of the fly ash It is difficult to be excited and can only play the role of micro-aggregate. If the dosage is too large, the concentration of reactants will decrease, the diffusion resistance of reactants will increase, and the mechanical properties will decrease.
  • the fiber is 0.3-0.8% of the total mass of the mixed dry material. Adding an appropriate amount of fiber can play a role in load transmission, crack deflection, and pull-out effect, thereby improving the mechanical properties of the material. However, excessive addition not only leads to increased costs, It is also easy to cause fiber agglomeration.
  • the fiber in the step 1 is any one of polyethylene fiber, polypropylene fiber, polyvinyl alcohol fiber, polyester fiber and polyamide fiber.
  • the mol ratio of magnesium sulfate in magnesium sulfate heptahydrate to active magnesium oxide in the step 2 is 1:5, and the quality of the admixture is 0.5 ⁇ 1% of active magnesium oxide, and the proportioning of raw materials is based on the hydration The theoretical value of the reaction stoichiometric equation is determined.
  • the admixture is any one of citric acid, citrate, tartaric acid, tartrate, phosphoric acid or phosphate, and the anion of the admixture can form a complex with hydrated magnesium oxide to delay the hydration reaction and hinder the precipitation of magnesium hydroxide Formation, but the addition of too much will lead to too long setting time, which will affect the construction efficiency.
  • the temperature for heating and dissolving is 30-50° C., and an appropriate temperature can accelerate the dissolution of magnesium sulfate and improve construction efficiency.
  • the water-cement ratio of the cement paste is 0.6-0.8, and the water-cement ratio has a great influence on the mechanical properties and workability of the material. If the water-cement ratio is too large, the setting rate of the material will be too slow , Affect the construction efficiency, if the water-cement ratio is too small, the working performance of the slurry will be deteriorated.
  • the stirring speed in the step 3 is 600-800 r/min, and the stirring time is 8-10 min. If the stirring time is too short and the speed is too slow, it will cause uneven mixing and affect the mechanical properties of the material; if the stirring time is too long and the speed is too fast, the coagulation rate of the slurry will be accelerated, resulting in poor working performance. If the foam density is too large, the foaming performance of the material will decrease and the water-cement ratio will increase; if the stirring speed is too fast, the stability of the foam will be destroyed, and if it is too slow, it will make it difficult for the foam to mix evenly with the slurry.
  • the foaming agent is diluted with water by 50 to 80 times, and the foaming agent is tetradecyldimethyl betaine, sodium dodecylbenzenesulfonate and sodium lauryl sulfate.
  • the foaming agent is tetradecyldimethyl betaine, sodium dodecylbenzenesulfonate and sodium lauryl sulfate.
  • One or more kinds are mixed in any ratio; the density of the foam is 30-60 kg/m 3 ; the speed of the low-speed stirring is 200-400 r/min.
  • Vapor deposition is to adhere to the surface of the material and the surface pore structure through the physical adsorption and capillary condensation of the modifier vapor on the surface of the porous material. The required amount is very small. Too many modifiers not only waste raw materials and increase costs, but also May cause clogging of the pores and reduce sound absorption performance.
  • the modifying agent in the step 6 is triethoxymethylsilane, isobutyltriethoxysilane, ⁇ -aminopropyl triethoxysilane, poly(methyl 3,3,3-triethoxysilane) Oxypropyl) siloxane, 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane and other organosilanes, the dropping amount of the modifier is 1m 2 magnesium-based pulverized coal Add 1-10 mL modifier dropwise to the gray porous material.
  • the temperature of the constant temperature condition in the step 6 is 55-70° C., and the time is 2-6 h. If the temperature is too high, the stability of the porous material will be affected, and if the temperature is too low, the modifier will evaporate slowly and the amount of deposition will be small, resulting in poor hydrophobic performance.
  • a surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material prepared according to the above method the density of the surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material is 251 ⁇ 306kg/m 3 , and the noise reduction coefficient is 0.65-0.7, the compressive strength reaches 1.8-2.2MPa, and the water contact angle is 129 ⁇ 151°.
  • the present invention has the following advantages:
  • the present invention uses a foaming machine to prepare low-density foam, and then mixes and foams it with basic magnesium sulfate cement slurry to obtain a low-density magnesium-based fly ash porous material; while using conventional chemical foaming or adding Surfactants are stirred and physically foamed, making it difficult to obtain low-density foamed materials.
  • fly ash can only act as a micro-aggregate in the weakly alkaline slurry of basic magnesium sulfate cement, the inappropriate foaming method will lead to a significant increase in density.
  • the density of the magnesium-based sound-absorbing material with a fly ash content of 30% can be as low as 250-300 kg/m 3 .
  • the porous sound-absorbing material prepared by the present invention has a uniform pore structure, large porosity, high porosity, and rich channels, which is conducive to the entry of sound waves into the material; a large number of 5 ⁇ 1 ⁇ 7 phase needle rods grow on the inner wall of the hole Shaped crystals form a fluffy micro-nano rough surface, which significantly enhances the friction and viscous force between the hole wall and the air, so that the sound energy can be quickly converted into heat energy, and the sound wave is sharply attenuated, achieving the purpose of efficient noise reduction.
  • the present invention uses the low-temperature vapor deposition method to carry out surface hydrophobic modification on the prepared magnesium-based fly ash porous sound-absorbing material.
  • the temperature is not higher than 70°C, and has no effect on the chemical composition and pore structure of the material;
  • the steam generated by the evaporation of the agent occurs physical adsorption and capillary condensation on the surface of the porous material, and is evenly deposited on the surface layer and the pore wall, making the surface exhibit excellent hydrophobic properties.
  • the thickness of modifier deposition is controllable, and the dosage of modifier is small, which effectively reduces the cost of raw materials.
  • the surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material prepared by the present invention has a noise reduction coefficient as high as 0.7, a compressive strength of 1.8 MPa, and the highest water contact angle when the density is 250 kg/ m3 It can reach 151° and meet the requirements of high-efficiency sound absorption, excellent mechanical properties and weather resistance. It can be widely used in tunnels, roads, railways and other places or environments that require sound absorption and noise reduction. The product has good formability and can be processed according to needs. into different shapes of sound-absorbing panels.
  • the surface-hydrophobic modified magnesium-based fly ash porous sound-absorbing material prepared by the present invention has simple process, low cost, no dust pollution, environmental protection, and is easy to realize industrial production.
  • Fig. 1 is the water contact angle of the material prepared by comparative example 1, 2 and embodiment 1, 2, 3, 4.
  • a is Comparative Example 1
  • b is Comparative Example 2
  • c is Example 1
  • d is Example 2
  • e is Example 3
  • f is Example 3.
  • Figure 2 shows the pore structure and microscopic morphology of the magnesium-based fly ash porous sound-absorbing material.
  • a method for preparing a surface hydrophobic modified basic magnesium sulfate cement porous sound-absorbing material comprising the following steps:
  • step (3) Add the mixed dry material obtained in step (1) to the magnesium sulfate solution obtained in step (2), and stir thoroughly to obtain a slurry;
  • step (6) Place the porous material obtained in step (5) in a petri dish, and drop 0.2 mL of 1H,1H,2H,2H-perfluorodecyltriethoxysilane around the material in the petri dish, cover the After the petri dish is sealed, put it into a 55°C incubator, and keep the temperature for 2h for surface deposition modification;
  • the water contact angle of the surface hydrophobic modified basic magnesium sulfate cement porous sound-absorbing material prepared in this example is shown in a in Figure 1, and the mechanical and sound-absorbing performance indicators are shown in Table 1.
  • a method for preparing a magnesium-based fly ash porous sound-absorbing material comprising the following steps:
  • step 3 Add the mixed dry material obtained in step 1 to the magnesium sulfate solution obtained in step 2, and stir thoroughly to obtain a slurry;
  • the water contact angle of the magnesium-based fly ash porous sound-absorbing material prepared in this example is shown in b in Figure 1, and the mechanical and sound-absorbing performance indicators are shown in Table 1.
  • a method for preparing a surface-hydrophobic modified magnesium-based fly ash porous sound-absorbing material comprising the following steps:
  • step (3) Add the mixed dry material obtained in step (1) to the magnesium sulfate solution obtained in step (2), and stir thoroughly to obtain a slurry;
  • step (6) Place the magnesium-based fly ash porous material obtained in step (5) in a petri dish, and drop 0.1 mL of triethoxymethylsilane, sealed the petri dish with a lid, put it into a 70°C incubator, and kept the temperature for 3 hours for surface deposition modification;
  • the water contact angle of the surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material prepared in this example is shown in c in Figure 1, and the mechanical and sound-absorbing performance indicators are shown in Table 1.
  • a method for preparing a surface-hydrophobic modified magnesium-based fly ash porous sound-absorbing material comprising the following steps:
  • step (3) Add the mixed dry material obtained in step (1) to the magnesium sulfate solution obtained in step (2), and stir thoroughly to obtain a slurry;
  • step (6) Place the magnesium-based fly ash porous material obtained in step (5) in a petri dish, and drop 0.15 mL of isobutyltriethoxysilane around the material in the petri dish, and seal the petri dish with a lid Put it in a constant temperature box at 65°C for 4 hours to carry out surface deposition modification;
  • the water contact angle of the surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material prepared in this example is shown in Figure 1 d, and the mechanical and sound-absorbing performance indicators are shown in Table 1.
  • a method for preparing a surface-hydrophobic modified magnesium-based fly ash porous sound-absorbing material comprising the following steps:
  • step (3) Add the mixed dry material obtained in step (1) to the magnesium sulfate solution obtained in step (2), and stir thoroughly to obtain a slurry;
  • step (6) Place the magnesium-based fly ash porous material obtained in step (5) in a petri dish, and drop 0.1 mL 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane, sealed the petri dish with a lid, put it in a 65°C incubator, and kept the temperature for 3 hours for surface deposition modification;
  • the water contact angle of the surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material prepared in this example is shown in e in Figure 1, and the mechanical and sound-absorbing performance indicators are shown in Table 1.
  • a method for preparing a surface-hydrophobic modified magnesium-based fly ash porous sound-absorbing material comprising the following steps:
  • step (3) Add the mixed dry material obtained in step (1) to the magnesium sulfate solution obtained in step (2), and stir thoroughly to obtain a slurry;
  • step (6) Place the magnesium-based fly ash porous material obtained in step (5) in a petri dish, and drop 0.2 mL of triethoxymethylsilane, sealed the petri dish with a lid, put it into a 60°C incubator, and kept the temperature for 4 hours for surface deposition modification;
  • the water contact angle of the surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material prepared in this example is shown in f in Figure 1, and the performance indicators are shown in Table 1.
  • the surface hydrophobic modified magnesium-based fly ash porous sound-absorbing material prepared in Examples 1-4 has a compressive strength of 1.8-2.2 MPa when the density is 251-306 kg/ m3 . Its mechanical properties are far superior to existing Portland cement porous materials. When the fly ash content is 30%, its noise reduction coefficient can still reach 0.65.
  • Fig. 1 is the water contact angle of the materials prepared by comparative examples 1, 2 and examples 1-4. From Figure 1b, it can be seen that the water contact angle of the unmodified sound-absorbing material is almost 0°, which is super-hydrophilic, and the surfaces of other modified materials all exhibit excellent hydrophobic properties. In addition, comparing a in Fig. 1 and e in Fig. 1, it is found that for the same 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane modifier, when the modification temperature increases and the time prolongs, the The surface hydrophobicity of the inventive material is significantly enhanced, and its water contact angle can reach 151°, showing superhydrophobicity.
  • Figure 2 shows the pore structure and microscopic morphology of the magnesium-based fly ash porous sound-absorbing material. It can be seen from the figure that the prepared material not only has a rich pore structure, but also a large number of needle-like crystals of basic magnesium sulfate grow on the inner wall of the hole, forming a fluffy micro-nano rough surface.

Abstract

本发明涉及吸声降噪领域，具体涉及一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法。为开发一种质轻高强、吸声性能优异、耐候性好、成本低廉和绿色环保的吸声材料，本发明以碱式硫酸镁水泥为胶凝剂、粉煤灰为矿物掺合料，采用物理发泡工艺，经过发泡机发泡、制浆、泡沫与浆体混合、浇筑养护、表面气相沉积疏水改性而制得，吸声材料的密度为251~306kg/m3，降噪系数为0.65-0.7，抗压强度达1.8-2.2MPa，水接触角为129~151°。

Description

一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法 技术领域
本发明涉及吸声降噪领域，具体涉及一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法。
 背景技术
近年来，随着工业、交通运输业的迅速发展，噪声污染逐渐加剧。目前采用控制噪音的常用方法是在道路两边设置声屏障、在厂房的周围加装吸音材料等。与隔音型声屏障相比，吸音型声屏障具有吸收声波的作用，可同时改善道路内外两侧的声环境。无机非金属多孔材料如岩棉、多孔陶瓷、泡沫水泥等，因具有阻燃、耐候性好等优点，是吸音型声屏障常用的单元板材料。虽然岩棉和多孔陶瓷吸声性能优异，但是岩棉生产过程污染严重，施工过程中危害职工健康，使用过程中还会造成环境污染等问题，多孔陶瓷制备过程能耗高、脆性、成本相对较高；传统的泡沫水泥虽然成本低，但力学和吸音性能难以同时兼顾。因此，亟需开发一种质轻高强、吸声性能优异、耐候性好、成本低廉和绿色环保的吸声材料。
专利CN207062795U公开了一种水泥基吸声材料，通过在材料坯体侧面设置吸声孔，增大了材料内部的多孔吸收结构与声波的直接接触面积，所制备的多孔吸声材料的平均吸声系数提高了6%~30%。虽然设置吸声孔有助于提升吸声性能，但不可避免地会影响材料的力学强度。专利CN110255987A公开了一种水泥基泡沫吸声材料，通过阴离子表面活性剂发泡并自然风干以产生更多孔隙，平均吸声系数提高了10%~30%，但是风干可能导致材料因表面失水过快而水化不完全，出现表面粉化现象。专利CN108529887B公开了一种以高钛型高炉缓冷渣为主要原料制备高强度多孔吸声材料的制备方法，但所制备的材料平均吸声系数仅为0.28~0.49。周冬冬等[碱式硫酸镁多孔吸声材料的可控制备及性能研究[J]. 化工学报, 2021, 72(6):3041-3052.]以碱式硫酸镁胶凝材料为基体材料、十四烷基甜菜碱为引气剂、粉煤灰为矿物掺合料，制备了密度为370~430 kg/m 3、降噪系数为0.5~0.6的多孔吸声材料。但是，该方法采用机械搅拌发泡导致发泡能力较低，难以获得密度低（<300 kg/m 3）、吸声性能好的材料。
鉴于此，本发明提出一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法，该吸声材料以碱式硫酸镁水泥为胶凝剂、以粉煤灰为矿物掺合料，采用物理发泡工艺，经过发泡机制泡、泡沫与浆体混合、浇筑养护、表面气相沉积疏水改性而制得的一种新型轻质高强、吸声性能好且具有表面疏水特性的多孔吸声材料。
 技术问题
本发明的目的在于提供一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法，该吸声材料以通孔为主、内壁呈绒毛状，吸声性能好，且具有质轻高强、表面疏水性和耐候性好的特点。
 技术解决方案
为了达到上述目的，本发明采用了下列技术方案：
一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，包括以下步骤：
步骤1，将氧化镁、粉煤灰与纤维混合均匀，得到混合干料；
步骤2，将七水硫酸镁、外加剂溶于水中，加热溶解得到含有外加剂的硫酸镁溶液；
步骤3，将步骤1得到的混合干料加入到步骤2得到的含有外加剂的硫酸镁溶液中，搅拌后得到水泥浆体；
步骤4，将发泡剂用水稀释，然后采用发泡机制备泡沫，并将泡沫通过低速搅拌加入到步骤3得到的水泥浆体中制得发泡浆体；
步骤5，将步骤4得到的发泡浆体浇筑到模具中，然后覆盖一层保鲜膜，室温下空气中养护1天后脱模，并继续养护至测试龄期，得到镁基粉煤灰多孔材料；
步骤6，将步骤5得到的镁基粉煤灰多孔材料周围滴加改性剂，密封后在恒温条件下进行表面沉积改性，得到改性材料；
步骤7，将步骤6得到的改性材料在室温下充分冷却后取出，得到一种表面疏水改性的镁基粉煤灰多孔吸声材料。
进一步，所述步骤1中的氧化镁为轻烧氧化镁，其中活性氧化镁的含量为55wt%~70wt%，氧化镁活性含量过高会使浆体凝结速率太快，导致其在浇筑过程中的流动性差；氧化镁活性含量过低，则浆体凝结速率过慢，泡沫的稳定时间与浆体的凝结时间不匹配，导致塌模。
所述粉煤灰为混合干料总质量的10%~30%，粉煤灰作为矿物掺合料，可降低材料成本，但在碱式硫酸镁弱碱性体系中，粉煤灰的火山灰活性难以被激发，只能起到微集料作用，掺量过大会导致反应物浓度减小，反应物扩散阻力增大，力学性能下降。
所述纤维为混合干料总质量的0.3~0.8%，加入适量的纤维可以起到负荷传递、裂纹偏转和拔出效应等作用，从而提升材料的力学性能，但过量加入不仅导致成本升高，还容易引起纤维团聚。
进一步，所述步骤1中的纤维为聚乙烯纤维、聚丙烯纤维、聚乙烯醇纤维、聚酯纤维、聚酰胺纤维中的任意一种。
进一步，所述步骤2中七水硫酸镁中的硫酸镁与活性氧化镁的摩尔比为1:5，所述外加剂的质量为活性氧化镁的0.5~1%，原料配比是根据水化反应计量方程式的理论值确定的。
所述外加剂为柠檬酸、柠檬酸盐、酒石酸、酒石酸盐、磷酸或磷酸盐中的任意一种，外加剂阴离子可与水合氧化镁形成络合物而延缓水化反应，阻碍氢氧化镁沉淀生成，但是加入量过大会导致凝结时间过长，影响施工效率。
所述加热溶解的温度为30~50℃，适宜的温度可以加速硫酸镁的溶解，提高施工效率。
进一步，所述步骤3中水泥浆体的水灰比为0.6~0.8，水灰比对材料的力学性能、工作性能均有较大的影响，水灰比过大则会导致材料凝结速率过慢、影响施工效率，水灰比过小则会导致浆体工作性能变差。
进一步，所述步骤3中搅拌的速度为600~800 r/min，搅拌的时间为8~10 min。搅拌时间过短、速度过慢，会导致混合不均匀，影响材料的力学性能；搅拌时间过长、速度过快，则会使得浆体的凝结速率加快，导致工作性能变差。泡沫的密度过大会使材料的发泡性能下降、水灰比增大；搅拌速度过快会破坏泡沫稳定性，过慢则会导致泡沫难以与浆体均匀混合。
进一步，所述步骤4中发泡剂用水稀释50~80倍，所述发泡剂为十四烷基二甲基甜菜碱、十二烷基苯磺酸钠及十二烷基硫酸钠中的一种或多种按任意比混合；所述泡沫的密度为30~60 kg/m 3；所述低速搅拌的速度为200~400 r/min。气相沉积是通过改性剂蒸气在多孔材料表面发生物理吸附和毛细管凝结的方式附着于材料的表面及表层孔结构中，需要量很小，过多的改性剂不仅浪费原料、增加成本，且可能导致孔道堵塞，降低吸声性能。
进一步，所述步骤6中改性剂为三乙氧基甲基硅烷、异丁基三乙氧基硅烷、γ―氨丙基三乙氧基硅烷、聚(甲基3,3,3-三氧丙基)硅氧烷、1H,1H,2H,2H-全氟癸基三乙氧基硅烷等有机硅烷中的任意一种，所述改性剂的滴加量为1m 2镁基粉煤灰多孔材料滴加1~10 mL改性剂。
进一步，所述步骤6中恒温条件的温度为55~70℃，时间为2~6 h。温度过高会影响多孔材料的稳定性，温度过低则改性剂蒸发慢，沉积量少，导致疏水性能变差。
一种根据上述方法制备的表面疏水改性镁基粉煤灰多孔吸声材料，所述表面疏水改性镁基粉煤灰多孔吸声材料的密度为251~306kg/m 3，降噪系数为0.65-0.7，抗压强度达1.8-2.2MPa，水接触角为129~151°。
有益效果
与现有技术相比本发明具有以下优点：
（1）本发明采用发泡机制备低密度泡沫，然后与碱式硫酸镁水泥浆体进行混合发泡，可获得低密度镁基粉煤灰多孔材料；而采用常规化学发泡或是通过添加表面活性剂搅拌物理发泡，难以获得低密度发泡材料。此外，由于粉煤灰在碱式硫酸镁水泥弱碱性浆体中只能起微集料作用，发泡方式不合适会导致密度显著增大。在本发明中，粉煤灰掺量为30%的镁基吸声材料密度可低至250~300 kg/m 3。
（2）本发明所制备的多孔吸声材料孔结构均匀，孔隙率大、开孔率高、孔道丰富，有利于声波进入到材料内部；孔内壁上生长有大量5·1·7相针杆状晶体，形成了绒毛状微纳粗糙表面，显著增强了孔壁与空气的摩擦和粘滞力，使声能快速转化为热能，声波急剧衰减，达到高效降噪的目的。
（3）本发明采用低温气相沉积法对所制备的镁基粉煤灰多孔吸声材料进行表面疏水改性，温度不高于70℃，对材料的化学组成、孔结构没有任何影响；改性剂蒸发产生的蒸气在多孔材料表面发生物理吸附和毛细管凝结而均匀沉积于表层及孔壁上，使其表面呈现优异的疏水性能。此外，改性剂沉积的厚度可控，且改性剂用量少，有效降低了原料成本。
（4）本发明所制备的表面疏水改性镁基粉煤灰多孔吸声材料，当密度为250 kg/m 3时，降噪系数高达 0.7，抗压强度可达1.8 MPa，水接触角最高可达151°，同时满足高效吸声、优异的力学性能和耐候性要求，可广泛应用于隧道、公路、铁路等需要吸声降噪的场所或者环境，制品的成型性好，可以根据需要加工成不同形状的吸声板。
（5）本发明所制备的表面疏水改性镁基粉煤灰多孔吸声材料，工艺简单、成本低廉、无粉尘污染、绿色环保，易实现工业化生产。
 附图说明
图1为对比实施例1、2和实施例1、2、3、4所制备材料的水接触角。
其中，a为对比实施例1，b为对比实施例2，c为实施例1，d为实施例2，e为实施例3，f为实施例3。
图2 为镁基粉煤灰多孔吸声材料的孔结构与微观形貌图。
 本发明的实施方式
下面通过具体实施例来进一步说明本发明的技术方案。本领域技术人员应该明了，所述具体实施方式仅仅是帮助理解本发明，不应视为对本发明的具体限制。
对比实施例1
一种表面疏水改性碱式硫酸镁水泥多孔吸声材料的制备方法，包括以下步骤：
（1）按活性氧化镁与硫酸镁摩尔比为5:1称取活性含量为61wt%的氧化镁1380g与七水硫酸镁982.6g，再称取聚丙烯纤维6.19g与柠檬酸8.44g，并将活性氧化镁和纤维混合均匀得到混合干料；
（2）称取水792.4g，将七水硫酸镁、柠檬酸与水混合在45℃的水浴锅中溶解得到硫酸镁溶液；
（3）将步骤（1）得到的混合干料加入到步骤（2）得到的硫酸镁溶液中，充分搅拌后得到浆体；
（4）将十四烷基二甲基甜菜碱按照1:60稀释后利用发泡机进行发泡制备出密度为45 kg/m 3的泡沫，并将泡沫通过以300 r/min的搅拌速度加入到步骤（3）得到的浆体中制得发泡浆体；
（5）将发泡浆体浇筑到模具中并裹膜，室温下空气中养护1天后脱模，并继续养护至测试龄期，得到碱式硫酸镁水泥多孔吸声材料；
（6）将步骤（5）得到的多孔材料置于培养皿中，并在培养皿中材料周围滴加0.2 mL 1H,1H,2H,2H-全氟癸基三乙氧基硅烷，用盖子将培养皿密封后放入55℃恒温箱中，恒温2h进行表面沉积改性；
（7）恒温改性后取出带盖子的培养皿冷却至室温，得到一种表面疏水改性的碱式硫酸镁水泥多孔吸声材料。
本实施例制得的表面疏水改性碱式硫酸镁水泥多孔吸声材料的水接触角如图1中a所示，力学和吸声性能指标见表1。
对比实施例2
一种镁基粉煤灰多孔吸声材料的其制备方法，包括以下步骤：
（1）按活性氧化镁与硫酸镁摩尔比为5:1称取活性含量为55wt%的氧化镁1530g与七水硫酸镁982.6g，再称取粉煤灰502.5g、聚乙烯醇纤维12.6g与柠檬酸8.44g，并将活性氧化镁、粉煤灰及纤维混合均匀得到混合干料；
（2）称取水919.8g，将七水硫酸镁、柠檬酸与水混合在45℃的水浴锅中溶解得到硫酸镁溶液；
（3）将步骤1得到的混合干料加入到步骤2得到的硫酸镁溶液中，充分搅拌后得到浆体；
（4）将十四烷基二甲基甜菜碱按照1:50稀释后利用发泡机进行发泡制备出密度为30 kg/m 3的泡沫，并将泡沫通过以200 r/min的搅拌速度加入到步骤（3）得到的浆体中制得发泡浆体；
（5）将发泡浆体浇筑到模具中并裹膜，室温下空气中养护1天后脱模，并继续养护至测试龄期，得到镁基粉煤灰多孔吸声材料。
本实施例制得的镁基粉煤灰多孔吸声材料的水接触角如图1中b所示，力学和吸声性能指标见表1。
实施例1
一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，包括以下步骤：
（1）按活性氧化镁与硫酸镁摩尔比为5:1称取活性含量为55wt%的氧化镁1530g与七水硫酸镁982.6g，再称取粉煤灰502.5g、聚乙烯醇纤维12.6g与柠檬酸8.44g，并将活性氧化镁、粉煤灰及纤维混合均匀得到混合干料；
（2）称取水919.8g，将七水硫酸镁、柠檬酸与水混合在45℃的水浴锅中溶解得到硫酸镁溶液；
（3）将步骤（1）得到的混合干料加入到步骤（2）得到的硫酸镁溶液中，充分搅拌后得到浆体；
（4）将十四烷基二甲基甜菜碱按照1:50稀释后利用发泡机进行发泡制备出密度为30 kg/m 3的泡沫，并将泡沫通过以200 r/min的搅拌速度加入到步骤（3）得到的浆体中制得发泡浆体；
（5）将发泡浆体浇筑到模具中并裹膜，室温下空气中养护1天后脱模，并继续养护至测试龄期，得到镁基粉煤灰多孔吸声材料；
（6）将步骤（5）得到的镁基粉煤灰多孔材料置于培养皿中，并在培养皿中材料周围滴加0.1 mL三乙氧基甲基硅烷，用盖子将培养皿密封后放入70℃恒温箱，恒温3 h进行表面沉积改性；
（7）恒温改性后取出带盖子的培养皿冷却至室温，得到一种表面疏水改性的镁基粉煤灰多孔吸声材料。
本实施例制得的表面疏水改性镁基粉煤灰多孔吸声材料的水接触角如图1中c所示，力学和吸声性能指标见表1。
实施例2
一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，包括以下步骤：
（1）按活性氧化镁与硫酸镁摩尔比为5:1称取活性含量为70wt%的氧化镁1202g与七水硫酸镁982.6g，再称取粉煤灰720.8g、聚丙烯纤维19.2g与柠檬酸8.44g，并将活性氧化镁、粉煤灰及纤维混合均匀得到混合干料；
（2）称取水1418.8g，将七水硫酸镁、柠檬酸与水混合在45℃的水浴锅中溶解得到硫酸镁溶液；
（3）将步骤（1）得到的混合干料加入到步骤（2）得到的硫酸镁溶液中，充分搅拌后得到浆体；
（4） 将十四烷基二甲基甜菜碱按照1:70稀释后利用发泡机进行发泡制备出密度为50 kg/m 3的泡沫，并将泡沫通过以400 r/min的搅拌速度加入到步骤（3）得到的浆体中制得发泡浆体；
（5）将发泡浆体浇筑到模具中并裹膜，室温下空气中养护1天后脱模，并继续养护至测试龄期，得到镁基粉煤灰多孔吸声材料；
（6）将步骤（5）得到的镁基粉煤灰多孔材料置于培养皿中，并在培养皿中材料周围滴加0.15 mL异丁基三乙氧基硅烷，用盖子将培养皿密封后放入65℃恒温箱中，恒温4 h进行表面沉积改性；
（7）恒温改性后取出带盖子的培养皿冷却至室温，得到一种表面疏水改性的镁基粉煤灰多孔吸声材料。
本实施例制得的表面疏水改性镁基粉煤灰多孔吸声材料的水接触角如图1中d所示，力学和吸声性能指标见表1。
实施例3
一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，包括以下步骤：
（1）按活性氧化镁与硫酸镁摩尔比为5:1称取活性含量为61wt%的氧化镁1380g与七水硫酸镁982.6g，再称取粉煤灰796.8g、聚丙烯纤维13.3g与柠檬酸8.44g，并将活性氧化镁、粉煤灰及纤维混合均匀得到混合干料；
（2）称取水1488.8g，将七水硫酸镁、柠檬酸与水混合在45℃的水浴锅中溶解得到硫酸镁溶液；
（3）将步骤（1）得到的混合干料加入到步骤（2）得到的硫酸镁溶液中，充分搅拌后得到浆体；
（4）将十四烷基二甲基甜菜碱按照1:80稀释后利用发泡机进行发泡制备出密度为60 kg/m 3的泡沫，并将泡沫通过以400 r/min的搅拌速度加入到步骤（3）得到的浆体中制得发泡浆体；
（5）将发泡浆体浇筑到模具中并裹膜，室温下空气中养护1天后脱模，并继续养护至测试龄期，得到镁基粉煤灰多孔吸声材料；
（6）将步骤（5）得到的镁基粉煤灰多孔材料置于培养皿中，并在培养皿中材料周围滴加0.1 mL 1H,1H,2H,2H-全氟癸基三乙氧基硅烷，用盖子将培养皿密封后放入65℃恒温箱中，恒温3 h进行表面沉积改性；
（7）恒温改性后取出带盖子的培养皿冷却至室温，得到一种表面疏水改性的镁基粉煤灰多孔吸声材料。
本实施例制得的表面疏水改性镁基粉煤灰多孔吸声材料的水接触角如图1中e所示，力学和吸声性能指标见表1。
实施例4
一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，包括以下步骤：
（1）按活性氧化镁与硫酸镁摩尔比为5:1称取活性含量为55wt%的氧化镁1530g与七水硫酸镁982.6g，再称取粉煤灰223.3g、聚乙烯醇纤维8.9g与柠檬酸8.44g，并将活性氧化镁、粉煤灰及纤维混合均匀得到混合干料；
（2）称取水836.6g，将七水硫酸镁与水混合在45℃的水浴锅中溶解得到硫酸镁溶液；
（3）将步骤（1）得到的混合干料加入到步骤（2）得到的硫酸镁溶液中，充分搅拌后得到浆体；
（4）将十四烷基二甲基甜菜碱按照1:50稀释后利用发泡机进行发泡制备出密度为30 kg/m 3的泡沫，并将泡沫通过以200 r/min的搅拌速度加入到步骤（3）得到的浆体中制得发泡浆体；
（5）将发泡浆体浇筑到模具中并裹膜，室温下空气中养护1天后脱模，并继续养护至测试龄期，得到镁基粉煤灰多孔吸声材料；
（6）将步骤（5）得到的镁基粉煤灰多孔材料置于培养皿中，并在培养皿中材料周围滴加0.2 mL三乙氧基甲基硅烷，用盖子将培养皿密封后放入60℃恒温箱，恒温4 h进行表面沉积改性；
（7）恒温改性后取出带盖子的培养皿冷却至室温，得到一种表面疏水改性的镁基粉煤灰多孔吸声材料。
本实施例制得的表面疏水改性镁基粉煤灰多孔吸声材料的水接触角如图1中f所示，性能指标见表1。
表 1 表面疏水改性镁基粉煤灰多孔吸声材料的性能
Figure 942497dest_path_image002
从表1可知，实施例1~4所制得的表面疏水改性镁基粉煤灰多孔吸声材料，当密度在251~306 kg/m 3时，其抗压强度达到1.8~2.2 MPa，其力学性能远优于现有硅酸盐水泥类多孔材料，当粉煤灰掺量为30%时，其降噪系数仍然可达0.65。
图1 为对比实施例1、2和实施例1~4所制备材料的水接触角。从图1中b可知，未改性的吸声材料的水接触角几乎为0°，具有超亲水性，其他改性后的材料表面均呈现优异的疏水性能。此外，对比图1中a和图1中e发现，对相同的1H,1H,2H,2H-全氟癸基三乙氧基硅烷改性剂，当改性温度升高、时间延长时，本发明材料表面疏水性能显著增强，其水接触角可达151°，呈现超疏水性能。
图2 为镁基粉煤灰多孔吸声材料的孔结构及微观形貌图。从图中可以看出，所制备的材料不仅具有丰富的孔结构，而且孔内壁上生长有大量碱式硫酸镁针杆状晶体，形成了绒毛状微纳粗糙表面。
以上实施方式仅用于说明本发明，而并非对本发明的限制，本领域的普通技术人员，在不脱离本发明的精神和范围的情况下，还可以做出各种变化和变型。因此，所有等同的技术方案也属于本发明的范畴，本发明的专利保护范围应由权利要求限定。
本发明说明书中未作详细描述的内容属于本领域专业技术人员公知的现有技术。尽管上面对本发明说明性的具体实施方式进行了描述，以便于本技术领的技术人员理解本发明，但应该清楚，本发明不限于具体实施方式的范围，对本技术领域的普通技术人员来讲，只要各种变化在所附的权利要求限定和确定的本发明的精神和范围内，这些变化是显而易见的，一切利用本发明构思的发明创造均在保护之列。

Claims (10)

  1. 一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，包括以下步骤：
    步骤1，将氧化镁、粉煤灰与纤维混合均匀，得到混合干料；所述粉煤灰为混合干料总质量的10%~30%；
    步骤2，将七水硫酸镁、外加剂溶于水中，加热溶解得到含有外加剂的硫酸镁溶液；
    步骤3，将步骤1得到的混合干料加入到步骤2得到的含有外加剂的硫酸镁溶液中，搅拌后得到水泥浆体；
    步骤4，将发泡剂用水稀释，然后采用发泡机制备泡沫，并将泡沫通过低速搅拌加入到步骤3得到的水泥浆体中制得发泡浆体；所述发泡剂用水稀释50~80倍，所述泡沫的密度为30~60 kg/m 3；
    步骤5，将步骤4得到的发泡浆体浇筑到模具中，然后覆盖一层保鲜膜，室温下空气中养护1天后脱模，并继续养护至测试龄期，得到镁基粉煤灰多孔材料；
    步骤6，将步骤5得到的镁基粉煤灰多孔材料周围滴加改性剂，密封后在恒温条件下进行表面沉积改性，得到改性材料；所述改性剂的滴加量为1m 2镁基粉煤灰多孔材料滴加1~10 mL改性剂；
    步骤7，将步骤6得到的改性材料在室温下充分冷却后取出，得到一种表面疏水改性的镁基粉煤灰多孔吸声材料。
  2. 根据权利要求1所述的一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，所述步骤1中的氧化镁为轻烧氧化镁，其中活性氧化镁的含量为55wt%~70wt%；所述纤维为混合干料总质量的0.3~0.8%。
  3. 根据权利要求1所述的一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，所述步骤1中的纤维为聚乙烯纤维、聚丙烯纤维、聚乙烯醇纤维、聚酯纤维、聚酰胺纤维中的任意一种。
  4. 根据权利要求2所述的一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，所述步骤2中七水硫酸镁中的硫酸镁与活性氧化镁的摩尔比为1:5，所述外加剂的质量为活性氧化镁的0.5~1%，所述外加剂为柠檬酸、柠檬酸盐、酒石酸、酒石酸盐、磷酸或磷酸盐中的任意一种；所述加热溶解的温度为30~50℃。
  5. 根据权利要求1所述的一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，所述步骤3中水泥浆体的水灰比为0.6~0.8。
  6. 根据权利要求1所述的一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，所述步骤3中搅拌的速度为600~800 r/min，搅拌的时间为8~10 min。
  7. 根据权利要求1所述的一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，所述步骤4中发泡剂为十四烷基二甲基甜菜碱、十二烷基苯磺酸钠及十二烷基硫酸钠中的一种或多种按任意比混合；所述低速搅拌的速度为200~400 r/min。
  8. 根据权利要求1所述的一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，所述步骤6中改性剂为三乙氧基甲基硅烷、异丁基三乙氧基硅烷、γ-氨丙基三乙氧基硅烷、聚(甲基3,3,3-三氧丙基)硅氧烷、1H,1H,2H,2H-全氟癸基三乙氧基硅烷中的任意一种。
  9. 根据权利要求1所述的一种表面疏水改性镁基粉煤灰多孔吸声材料的制备方法，其特征在于，所述步骤6中恒温条件的温度为55~70℃，时间为2~6 h。
  10. 一种根据权利要求1~9任一项所述方法制备的表面疏水改性镁基粉煤灰多孔吸声材料，其特征在于，所述表面疏水改性镁基粉煤灰多孔吸声材料的密度为251~306kg/m 3，降噪系数为0.65-0.7，抗压强度达1.8-2.2MPa，水接触角为129~151°。
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101244920A (zh) * 2008-03-25 2008-08-20 东南大学 道路声屏障用水泥基吸声材料及其制备方法
CN105503239A (zh) * 2015-12-18 2016-04-20 广东龙湖科技股份有限公司 一种质轻高强硫氧镁发泡板材及其制备方法
US20170283324A1 (en) * 2016-04-04 2017-10-05 Futong Cui Fire retardant construction materials
CN112661477A (zh) * 2021-01-09 2021-04-16 山西大学 改性聚苯乙烯-碱式硫酸镁水泥复合保温材料的制备方法
CN113698171A (zh) * 2021-09-08 2021-11-26 山西大学 一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108726980A (zh) * 2018-07-05 2018-11-02 南京倍立达欧陆装饰艺术工程有限公司 一种疏水自洁菱镁墙板
CN109503009B (zh) * 2018-12-07 2021-05-14 山西大学 一种改性硫酸镁水泥及其制备方法
CN109678448A (zh) * 2019-02-25 2019-04-26 北京科技大学 一种硫氧镁水泥轻质高强泡沫板及其制备方法
CN110627526B (zh) * 2019-11-06 2020-12-25 山西大学 一种轻质高强碱式硫酸镁发泡保温材料及其制备方法
CN113277762A (zh) * 2021-06-23 2021-08-20 山西大学 一种快凝早强碱式硫酸镁水泥及制备方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101244920A (zh) * 2008-03-25 2008-08-20 东南大学 道路声屏障用水泥基吸声材料及其制备方法
CN105503239A (zh) * 2015-12-18 2016-04-20 广东龙湖科技股份有限公司 一种质轻高强硫氧镁发泡板材及其制备方法
US20170283324A1 (en) * 2016-04-04 2017-10-05 Futong Cui Fire retardant construction materials
CN112661477A (zh) * 2021-01-09 2021-04-16 山西大学 改性聚苯乙烯-碱式硫酸镁水泥复合保温材料的制备方法
CN113698171A (zh) * 2021-09-08 2021-11-26 山西大学 一种表面疏水改性镁基粉煤灰多孔吸声材料及其制备方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ZHOU DONGDONG, FANG LI; YANG QIAOZHEN; QIU RUIFANG; CHENG FANGQIN: "Preparation and performance of base magnesium sulfate porous sound absorbing materials", CIESC JOURNAL, HUAXUE GONGYE CHUBANSHE, CN, vol. 72, no. 6, 16 March 2021 (2021-03-16), CN , pages 3041 - 3052, XP093045449, ISSN: 0438-1157, DOI: 10.11949/0438-1157.20201731 *

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