High-strength silicon-aluminum polymeric material and preparation method thereof

Abstract

The invention relates to a high-strength silicon-aluminum polymeric material and a preparation method thereof. According to the technical scheme, the method comprises the following steps: ultrasonically washing quartz, carrying out solid-liquid separation, and drying to obtain pretreated quartz; mixing tetraethoxysilane, water and absolute ethyl alcohol, adjusting the pH value, heating and stirring to obtain a modified solution; mixing the pretreated quartz with the modified liquid, stirring, carrying out solid-liquid separation, and drying to obtain modified quartz; mixing sodium metasilicate with water to obtain an alkali activator; mixing a silicon-aluminum raw material, the modified quartz and an alkali activator, and uniformly stirring to obtain silicon-aluminum polymer material slurry; and pouring the silicon-aluminum polymeric material slurry into a mold, and carrying out first maintenance, demolding and second maintenance to obtain the high-strength silicon-aluminum polymeric material. The preparation method is simple in process and suitable for large-scale production, and the prepared high-strength silicon-aluminum polymeric material has the characteristics that a silicon-aluminum structure is compactly combined with a quartz interface, the overall structure is stable, and the compressive strength of the silicon-aluminum polymeric material is effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of building material preparation technology. Specifically, it relates to a high-strength silicon-aluminum polymer material and its preparation method. Background Technology

[0002] Silicon-aluminum polymers are amorphous inorganic materials made from silicon-aluminum-rich raw materials (such as metakaolin, fly ash, and slag) through alkali activation, releasing SiO4 tetrahedra and AlO4 tetrahedra. These tetrahedra are then linked by oxygen bridging to form a three-dimensional network structure. They possess advantages such as low carbon footprint, environmental friendliness, rapid hardening, acid and alkali resistance, and high-temperature resistance, and are widely used in building materials, solid waste disposal, and environmental remediation. However, existing silicon-aluminum polymers suffer from high brittleness, insufficient density, and numerous microstructural defects, which limit their compressive strength development and long-term durability. Therefore, researchers have explored ways to improve the performance of silicon-aluminum polymers by incorporating tailings fillers, active silicon sources, or organic modifiers.

[0003] Quartz, as the main inert component of silicate tailings fillers, has high potential to enhance the activity of aluminosilicate polymers. However, its surface is mainly composed of inert Si-O-Si and Si-OH structures, lacking active surfaces and making it difficult to chemically react with the aluminosilicate structures in the polymers; it primarily serves a physical support role. Due to poor interfacial bonding, debonding and microcracks easily occur between the filler and the matrix, thus weakening the overall mechanical properties of the system. To address these issues, researchers have attempted to improve the interfacial interaction between the filler and the aluminosilicate polymer matrix by introducing nano-SiO2, silane coupling agents, or chemical fibers.

[0004] The patented technology, "A Nano-Silica and Hybrid Fiber Reinforced Polymer Concrete with Improved Compressive Strength and Its Preparation Method" (CN116675478A), incorporates nano-SiO2, polyvinyl alcohol fiber, and steel fiber into a silicon-aluminum polymer material system, increasing its compressive strength from 39.5 MPa to 50.1 MPa. However, the compressive strength enhancement effect of the silicon-aluminum polymer material prepared by this technology is limited, and nano-SiO2 is prone to agglomeration, requiring surface dispersion assistance and a cumbersome mixing process.

[0005] The patented technology, "A graphene oxide-silane coupling agent-geopolymer composite material and its preparation method" (CN111253119A), uses graphene oxide as a filler and introduces a silane coupling agent to increase the interfacial adhesion between graphene oxide and the silicon-aluminum polymer material and improve the microstructure. However, this technology is difficult to disperse graphene oxide in a high pH environment, requiring the use of sodium lignosulfonate / calcium, sodium dodecyl sulfonate / calcium, and polycarboxylate as dispersants and the introduction of multiple chemical agents. The process is complex and not suitable for large-scale structural material applications.

[0006] The patented technology, "A Chitosan-Modified Polymer Cementitious Material" (CN117720309A), uses blast furnace slag as raw material and sand and gravel as fillers to prepare a silicon-aluminum polymer material by incorporating chitosan. In the material with chitosan, the addition of fillers reduces the optimal compressive strength from 60.22 MPa to 52.81 MPa. In the material with added fillers, the addition of chitosan further reduces the compressive strength from 53.26 MPa to 52.81 MPa. Although this technology can improve the flexural toughness of the material, the poor interfacial density between the filler and the silicon-aluminum polymer material leads to a decrease in the compressive strength of the silicon-aluminum polymer material. The addition of chitosan further deteriorates the compressive strength and affects the stability of the overall structure.

[0007] The patented technology, "A micro / nano fiber composite toughened and reinforced geopolymer based on pore optimization and its preparation method" (CN108863127A), mixes metakaolin powder with sodium carbonate, defoamer, and polyvinyl alcohol fiber, and then adds a modified sodium silicate activator incorporating carbon nanotubes. The optimal compressive strength of the silicon-aluminum polymer material is 43.5 MPa. This technology focuses on toughening and improvement, but the increase in compressive strength is very limited. It mainly has a physical filling effect. Moreover, sodium carbonate is prone to migrate to the surface in a humid and hot environment, forming crystal pores, which poses a risk of efflorescence and affects the stability of the overall structure. It is not suitable for large-scale production applications.

[0008] In summary, existing methods suffer from problems such as poor interfacial density between the silicon-aluminum polymer matrix and the filler, poor overall stability, limited improvement in compressive strength, complex preparation process, and difficulty in large-scale production. Summary of the Invention

[0009] The present invention aims to overcome the defects of the prior art and provides a high-strength silicon-aluminum polymer material and its preparation method that are simple to process and suitable for large-scale production. The high-strength silicon-aluminum polymer material prepared by this method has a dense bond between the silicon-aluminum structure and the quartz interface, a stable overall structure, and a significant improvement in compressive strength.

[0010] To achieve the above objectives, the specific steps of the technical solution adopted by the present invention are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 1~20:4~80:100; adjust the pH to 4~5 with dilute hydrochloric acid, heat and stir to obtain modified solution.

[0011] Step 2: Mix the pretreated quartz and the modification liquid at a mass ratio of 1:2.1~4, stir at 50~70℃ for 1~3 h, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0012] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.2~1.6 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.3~0.6:1.1~1.6 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0013] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0014] The quartz grain size is ≤150μm.

[0015] The anhydrous ethanol has a purity of ≥99.7 vol.

[0016] The SiO2 content in the tetraethyl orthosilicate is ≥28.4wt%.

[0017] The heating and stirring temperature is 50~70℃, and the stirring time is 1~2 hours.

[0018] The sodium metasilicate contains 44-47 wt% SiO2.

[0019] The silicon-aluminate raw material is metakaolin or fly ash; in the silicon-aluminate raw material: SiO2 content ≥ 40wt%, Al2O3 content ≥ 30wt%.

[0020] The temperature for the first curing is 60~80℃, and the curing time is 6~12 hours.

[0021] The second curing temperature is room temperature, and the curing time is 7~28 days.

[0022] By adopting the above technical solution, the present invention has the following advantages compared with the prior art: 1. This invention utilizes the hydrolysis-condensation reaction of tetraethyl orthosilicate to generate a large number of active silicon-oxygen vacancies and silanol groups in situ on the quartz surface. These groups can undergo condensation reactions with the Si-OH and Al-OH groups in the silicon-aluminum structure of the silicon-aluminum polymer material, forming stable Si-O-Si(Al) bonds. This achieves chemical bonding between the quartz filler and the matrix, significantly improving the density and structural integrity of the interfacial bonding of the high-strength silicon-aluminum polymer material. Compared with traditional physical filling modification techniques for silicon-aluminum polymer materials, the interfacial bonding between the filler and the silicon-aluminum polymer material matrix of this invention is denser, the overall structure is more stable, and the compressive strength is further improved.

[0023] 2. The quartz modified with tetraethyl orthosilicate in this invention has a smoother surface and a certain degree of hydrophilicity, which is beneficial for uniform contact with raw materials. It can be directly incorporated into the silicon-aluminum polymer material system, exhibits good dispersibility, has little impact on slurry flowability, and requires no external dispersants or defoamers. Compared with coupling agents or chemical fiber modification technologies, the preparation process of this invention is simple and the overall structure is stable, making it suitable for large-scale production.

[0024] 3. The silica-alumina polymer material prepared by modifying quartz with tetraethyl orthosilicate according to this invention, tested according to GB / T50081 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete", has a compressive strength of 56.26~72.69 MPa after curing. Compared with silica-alumina polymer materials prepared under the same conditions without modification of quartz, this invention significantly improves the interfacial density between quartz and the matrix, increasing the compressive strength of the silica-alumina polymer material from 45.37 MPa to 72.69 MPa, an increase of 60.21%.

[0025] Therefore, the process of this invention is simple and suitable for large-scale production. The high-strength silicon-aluminum polymer material prepared has the characteristics of significantly improving the density of the bond between the silicon-aluminum structure and the quartz interface, stable overall structure, and effectively improving the compressive strength of the silicon-aluminum polymer material. Attached Figure Description

[0026] Figure 1 This is a scanning electron microscope image of a silicon-aluminum polymer material prepared using unmodified quartz; Figure 2 This is a scanning electron microscope image of a high-strength silicon-aluminum polymer material prepared according to the present invention. Detailed Implementation

[0027] The present invention will be further described below with reference to specific embodiments, but this is not intended to limit the scope of protection thereof: A high-strength silicon-aluminum polymer material and its preparation method. The specific steps of the method described in this embodiment are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 1~20:4~80:100; adjust the pH to 4~5 with dilute hydrochloric acid, heat and stir to obtain modified solution.

[0028] Step 2: Mix the pretreated quartz and the modification liquid at a mass ratio of 1:2.1~4, stir at 50~70℃ for 1~3 h, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0029] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.2~1.6 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.3~0.6:1.1~1.6 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0030] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0031] The heating and stirring temperature is 50~70℃, and the stirring time is 1~2 hours.

[0032] The sodium metasilicate contains 44-47 wt% SiO2.

[0033] The silicon-aluminate raw material is metakaolin or fly ash; in the silicon-aluminate raw material: SiO2 content ≥ 40wt%, Al2O3 content ≥ 30wt%.

[0034] The temperature for the first curing is 60~80℃, and the curing time is 6~12 hours.

[0035] The second curing temperature is room temperature, and the curing time is 7~28 days.

[0036] In this specific implementation: The quartz grain size is ≤150 μm; The anhydrous ethanol has a purity of ≥99.7 vol%. The SiO2 content in the tetraethyl orthosilicate is ≥28.4wt%.

[0037] The details will not be repeated in the examples.

[0038] Example 1 A high-strength silicon-aluminum polymer material and its preparation method. The specific steps of the method described in this embodiment are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 1:4:100; adjust the pH to 4 with dilute hydrochloric acid, heat and stir to obtain the modified solution.

[0039] Step 2: Mix the pretreated quartz and the modification liquid at a mass ratio of 1:2.1, stir at 50°C for 3 h, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0040] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.6 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.6:1.6 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0041] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0042] The heating and stirring temperature is 70°C, and the stirring time is 1 hour.

[0043] The sodium metasilicate contains 44 wt% SiO2.

[0044] The aluminosilicate raw material is metakaolin; in the aluminosilicate raw material: the SiO2 content is 41.23wt% and the Al2O3 content is 51.20wt%.

[0045] The temperature for the first curing was 80℃, and the curing time was 11 hours.

[0046] The second curing was performed at room temperature for 7 days.

[0047] In this embodiment, the compressive strength of the high-strength silicon-aluminum polymer material was tested to be 56.26 MPa.

[0048] Example 2 A high-strength silicon-aluminum polymer material and its preparation method. The specific steps of the method described in this embodiment are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 5:20:100; adjust the pH to 5 with dilute hydrochloric acid, heat and stir to obtain the modified solution.

[0049] Step 2: Mix the pretreated quartz and the modification liquid at a mass ratio of 1:2.5, stir at 55°C for 2 hours, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0050] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.5 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.4:1.3 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0051] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0052] The heating and stirring temperature is 50°C, and the stirring time is 2 hours.

[0053] The sodium metasilicate contains 45 wt% SiO2.

[0054] The aluminosilicate raw material is metakaolin; the aluminosilicate raw material contains 59.64 wt% SiO2 and 31.15 wt% Al2O3.

[0055] The temperature for the first curing was 70℃, and the curing time was 8 hours.

[0056] The second curing was performed at room temperature for 12 days.

[0057] In this embodiment, the compressive strength of the high-strength silicon-aluminum polymer material was tested to be 60.52 MPa.

[0058] Example 3 A high-strength silicon-aluminum polymer material and its preparation method. The specific steps of the method described in this embodiment are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 10:40:100; adjust the pH to 4.5 with dilute hydrochloric acid, heat and stir to obtain the modified solution.

[0059] Step 2: Mix the pretreated quartz and the modified liquid at a mass ratio of 1:3, stir at 60°C for 2 h, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0060] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.4 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.5:1.4 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0061] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0062] The heating and stirring temperature is 60°C, and the stirring time is 1.5 hours.

[0063] The sodium metasilicate contains 46 wt% SiO2.

[0064] The aluminosilicate raw material is metakaolin; the aluminosilicate raw material contains 50.03 wt% SiO2 and 44.83 wt% Al2O3.

[0065] The temperature for the first curing was 60℃, and the curing time was 6 hours.

[0066] The second curing temperature was room temperature, and the second curing time was 28 days.

[0067] The compressive strength of the high-strength silicon-aluminum polymer material tested in this embodiment is 72.69 MPa.

[0068] Example 4 A high-strength silicon-aluminum polymer material and its preparation method. The specific steps of the method described in this embodiment are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 15:60:100; adjust the pH to 4.5 with dilute hydrochloric acid, heat and stir to obtain the modified solution.

[0069] Step 2: Mix the pretreated quartz and the modification liquid at a mass ratio of 1:3.5, stir at 65°C for 1 hour, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0070] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.3 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.3:1.1 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0071] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0072] The heating and stirring temperature is 50°C, and the stirring time is 1.5 hours.

[0073] The sodium metasilicate contains 47 wt% SiO2.

[0074] The aluminosilicate raw material is metakaolin; the aluminosilicate raw material contains 53.50 wt% SiO2 and 41.73 wt% Al2O3.

[0075] The temperature for the first curing was 70℃, and the curing time was 7 hours.

[0076] The second curing was performed at room temperature for 16 days.

[0077] In this embodiment, the compressive strength of the high-strength silicon-aluminum polymer material was tested to be 66.71 MPa.

[0078] Example 5 A high-strength silicon-aluminum polymer material and its preparation method. The specific steps of the method described in this embodiment are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 20:80:100; adjust the pH to 4 with dilute hydrochloric acid, heat and stir to obtain the modified solution.

[0079] Step 2: Mix the pretreated quartz and the modified liquid at a mass ratio of 1:4, stir at 70°C for 1 hour, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0080] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.2 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.5:1.5 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0081] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0082] The heating and stirring temperature is 70°C, and the stirring time is 1 hour.

[0083] The sodium metasilicate contains 46 wt% SiO2.

[0084] The silicoaluminous raw material is fly ash; the silicoaluminous raw material contains 50.23 wt% SiO2 and 39.29 wt% Al2O3.

[0085] The temperature for the first curing was 75℃, and the curing time was 9 hours.

[0086] The second curing temperature was room temperature, and the second curing time was 20 days.

[0087] In this embodiment, the compressive strength of the high-strength silicon-aluminum polymer material was tested to be 64.35 MPa.

[0088] Example 6 A high-strength silicon-aluminum polymer material and its preparation method. The specific steps of the method described in this embodiment are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 10:50:100; adjust the pH to 4.5 with dilute hydrochloric acid, heat and stir to obtain the modified solution.

[0089] Step 2: Mix the pretreated quartz and the modification liquid at a mass ratio of 1:2.8, stir at 60°C for 2 hours, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0090] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.2 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.4:1.4 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0091] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0092] The heating and stirring temperature is 60°C, and the stirring time is 1.5 hours.

[0093] The sodium metasilicate contains 45 wt% SiO2.

[0094] The silicoaluminous raw material is fly ash; the silicoaluminous raw material contains 55.86 wt% SiO2 and 35.21 wt% Al2O3.

[0095] The temperature for the first curing was 80℃, and the curing time was 12 hours.

[0096] The second curing temperature was room temperature, and the second curing time was 28 days.

[0097] In this embodiment, the compressive strength of the high-strength silicon-aluminum polymer material was tested to be 67.73 MPa.

[0098] Example 7 A high-strength silicon-aluminum polymer material and its preparation method. The specific steps of the method described in this embodiment are as follows: Step 1: Wash the quartz crystals with water, separate the solid and liquid, and vacuum dry them until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 20:70:100; adjust the pH to 5 with dilute hydrochloric acid, heat and stir to obtain the modified solution.

[0099] Step 2: Mix the pretreated quartz and the modification liquid at a mass ratio of 1:3.7, stir at 50°C for 3 hours, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz.

[0100] Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.6 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.3:1.2 and stir until homogeneous to obtain an aluminosilicate polymer slurry.

[0101] Step 4: Pour the silicon-aluminum polymer slurry into a mold, perform the first curing, demold, and perform the second curing to obtain a high-strength silicon-aluminum polymer material.

[0102] The heating and stirring temperature is 70°C, and the stirring time is 1 hour.

[0103] The sodium metasilicate contains 47 wt% SiO2.

[0104] The silicoaluminous raw material is fly ash; the silicoaluminous raw material contains 47.86 wt% SiO2 and 46.52 wt% Al2O3.

[0105] The temperature for the first curing was 65℃, and the curing time was 10 hours.

[0106] The second curing temperature was room temperature, and the second curing time was 24 days.

[0107] The compressive strength of the high-strength silicon-aluminum polymer material tested in this embodiment is 61.32 MPa.

[0108] Comparative Example 1 A method for preparing aluminosilicate polymeric materials from unmodified quartz. The specific steps of the method described in this embodiment are as follows: Step 1: Mix sodium metasilicate and water at a mass ratio of 1:1.4 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkaline activator.

[0109] Step 2: Mix the silica-alumina raw materials, alkali activator and quartz in a mass ratio of 1:0.5:1.5 and stir evenly to obtain a silica-alumina polymer slurry; Step 3: Place the silicon-aluminum polymer slurry in a mold, cure, demold, and cure at room temperature to obtain the silicon-aluminum polymer material.

[0110] The quartz grain size is ≤150μm; The sodium metasilicate contains 45 wt% SiO2.

[0111] The aluminosilicate raw material is metakaolin; the aluminosilicate raw material contains 50.03 wt% SiO2 and 44.83 wt% Al2O3.

[0112] The curing temperature is 60℃ and the curing time is 6 hours.

[0113] The curing time at room temperature is 28 days.

[0114] The comparative example was tested and found that the compressive strength of the silicon-aluminum polymer material was 45.37 MPa.

[0115] Comparative Example 2 A method for preparing aluminosilicate polymeric materials from unmodified quartz. The specific steps of the method described in this embodiment are as follows: Step 1: Mix sodium metasilicate and water at a mass ratio of 1:1.2 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkaline activator.

[0116] Step 2: Mix the silica-alumina raw materials, alkali activator and quartz in a mass ratio of 1:0.4:1.4 and stir evenly to obtain a silica-alumina polymer slurry; Step 3: Place the silicon-aluminum polymer slurry in a mold, cure, demold, and cure at room temperature to obtain the silicon-aluminum polymer material.

[0117] The quartz grain size is ≤150μm; The sodium metasilicate contains 45 wt% SiO2.

[0118] The silicoaluminous raw material is fly ash; the silicoaluminous raw material contains 55.86 wt% SiO2 and 35.21 wt% Al2O3.

[0119] The curing temperature is 80℃, and the curing time is 12 hours.

[0120] The curing time at room temperature is 28 days.

[0121] The comparative example was tested and found that the compressive strength of the silicon-aluminum polymer material was 41.66 MPa.

[0122] This specific implementation method has the following advantages compared with the prior art: 1. This specific embodiment utilizes the hydrolysis-condensation reaction of tetraethyl orthosilicate to generate a large number of active silicon-oxygen vacancies and silanol groups in situ on the quartz surface. These groups can undergo condensation reactions with the Si-OH and Al-OH groups in the silicon-aluminum structure of the silicon-aluminum polymer material, forming stable Si-O-Si(Al) bonds. This achieves chemical bonding between the quartz filler and the matrix, significantly improving the density and structural integrity of the interfacial bonding of the high-strength silicon-aluminum polymer material. Compared with existing physically filled silicon-aluminum polymer material modification technologies, the silicon-aluminum polymer materials prepared by existing technologies, such as... Figure 1 As shown, Figure 1 The image shows a scanning electron microscope image of the silicon-aluminum polymer material prepared using unmodified quartz in Comparative Example 1; the high-strength silicon-aluminum polymer material prepared in this specific embodiment is as follows: Figure 2 As shown, Figure 2 Scanning electron microscope image of the high-strength silica-alumina polymer material prepared in Example 3. Figure 1 It can be seen that in Comparative Example 1, the interface between the quartz and silicon-aluminum network structure in the silicon-aluminum polymer material has large cracks, resulting in poor interfacial bonding and reduced compressive strength. Figure 2 It can be seen that the high-strength silicon-aluminum polymer material in Example 3 has a dense interface between the quartz and silicon-aluminum network structure, which significantly improves the compressive strength. Therefore, the filler in this specific embodiment has a denser interface with the silicon-aluminum polymer material matrix, a more stable overall structure, and further improves the compressive strength.

[0123] 2. In this specific embodiment, the quartz modified with tetraethyl orthosilicate has a smoother surface and a certain degree of hydrophilicity, which is beneficial for uniform contact with raw materials. It can be directly incorporated into the silicon-aluminum polymer material system, exhibits good dispersibility, has little impact on slurry flowability, and requires no external dispersants or defoamers. Compared with coupling agent or chemical fiber modification technology, the preparation process of this specific embodiment is simple and the overall structure is stable, making it suitable for large-scale production.

[0124] 3. The silica-alumina polymer material prepared by modifying quartz with tetraethyl orthosilicate in this specific embodiment, tested according to GB / T50081 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete", has a compressive strength of 56.26~72.69 MPa after curing. Compared with silica-alumina polymer materials prepared under the same conditions without modified quartz, this specific embodiment significantly improves the interfacial density between quartz and the matrix, increasing the compressive strength of the silica-alumina polymer material from 45.37 MPa to 72.69 MPa, an increase of 60.21%.

[0125] Therefore, the process described in this specific embodiment is simple and suitable for large-scale production. The high-strength silicon-aluminum polymer material prepared has the characteristics of significantly improving the density of the bond between the silicon-aluminum structure and the quartz interface, stable overall structure, and effectively improving the compressive strength of the silicon-aluminum polymer material.

Claims

1. A method for preparing a high-strength silicon-aluminum polymer material, characterized in that... The specific steps of the preparation method are as follows: Step 1: Wash the quartz crystal with water, separate the solid and liquid, and vacuum dry it until the mass is constant to obtain pretreated quartz; mix tetraethyl orthosilicate, water and anhydrous ethanol according to the mass ratio of tetraethyl orthosilicate:water:anhydrous ethanol of 1~20:4~80:100; adjust the pH to 4~5 with dilute hydrochloric acid, heat and stir to obtain modified solution. Step 2: Mix the pretreated quartz and the modification liquid at a mass ratio of 1:2.1~4, stir at 50~70℃ for 1~3 h, separate the solid and liquid, and vacuum dry until the mass is constant to obtain modified quartz. Step 3: Mix sodium metasilicate and water at a mass ratio of 1:1.2~1.6 to obtain a mixture. Stir the mixture until it becomes clear to obtain an alkali activator. Mix the aluminosilicate raw material, modified quartz and alkali activator at a mass ratio of 1:0.3~0.6:1.1~1.6 and stir until homogeneous to obtain an aluminosilicate polymer slurry. Step 4: Pour the silicon-aluminum polymer slurry into the mold, perform the first curing, demold, and perform the second curing to obtain the high-strength silicon-aluminum polymer material.

2. The method for preparing the high-strength silicon-aluminum polymer material according to claim 1, characterized in that, The quartz grain size is ≤150μm.

3. The method for preparing the high-strength silicon-aluminum polymer material according to claim 1, characterized in that, The anhydrous ethanol has a purity of ≥99.7 vol.

4. The method for preparing the high-strength silicon-aluminum polymer material according to claim 1, characterized in that, The SiO2 content in the tetraethyl orthosilicate is ≥28.4wt%.

5. The method for preparing the high-strength silicon-aluminum polymer material according to claim 1, characterized in that, The heating and stirring temperature is 50~70℃, and the stirring time is 1~2 hours.

6. The method for preparing the high-strength silicon-aluminum polymer material according to claim 1, characterized in that, The sodium metasilicate contains 44-47 wt% SiO2.

7. The method for preparing the high-strength silicon-aluminum polymer material according to claim 1, characterized in that, The silicon-aluminate raw material is metakaolin or fly ash; in the silicon-aluminate raw material: SiO2 content ≥ 40wt%, Al2O3 content ≥ 30wt%.

8. The method for preparing the high-strength silicon-aluminum polymer material according to claim 1, characterized in that, The temperature for the first curing is 60~80℃, and the curing time is 6~12 hours.

9. The method for preparing the high-strength silicon-aluminum polymer material according to claim 1, characterized in that, The second curing temperature is room temperature, and the curing time is 7~28 days.

10. A high-strength silicon-aluminum polymer material, characterized in that, The high-strength silicon-aluminum polymer material is a high-strength silicon-aluminum polymer material prepared by the preparation method of the high-strength silicon-aluminum polymer material according to any one of claims 1 to 9.

Images