A slag-based non-burned brick and a preparation method thereof

Abstract

The application discloses a slag soil-based unfired brick and a preparation method thereof, and relates to the technical field of unfired bricks.The slag soil-based unfired brick comprises the following raw materials in parts by weight: engineering slag soil: 80-100 parts, cement: 10-12 parts, deionized water: 30-50 parts, alkali activator: 10-12 parts, defoaming agent: 1-2 parts, basalt fiber: 1-3 parts, and curing agent: 5-10 parts.Through the reaction of chloropropene magnesium and phenyltrichlorosilane, trienyl(phenyl)silane is obtained;then 1,5-pentanediol is added in batches to prepare a hyperbranched organosilicon resin, which is then grafted onto an epoxy resin to prepare a hyperbranched organosilicon modified epoxy resin;and then gamma-aminopropyl triethoxysilane is grafted to obtain a curing agent.The slag soil-based unfired brick prepared by the application has the characteristics of good compressive strength and low water absorption.

Description

Technical Field

[0001] This invention relates to the field of non-fired brick technology, specifically to a slag-based non-fired brick and its preparation method. Background Technology

[0002] With the acceleration of urbanization, the demand for building materials in the construction industry is constantly increasing. However, the traditional production method of sintered bricks faces problems such as resource waste, high energy consumption, and environmental pollution. In recent years, non-fired bricks have gradually gained attention as a green building material. The production of non-fired bricks does not require high-temperature firing, effectively reducing energy consumption and carbon emissions. Simultaneously, it utilizes construction waste and other raw materials, achieving resource recycling. Among the many types of non-fired bricks, the development of waste-based non-fired bricks has significant practical implications. Construction waste is a large amount of waste generated during urban construction and infrastructure development. Its accumulation not only occupies land resources but may also pollute the environment. Converting construction waste into raw materials for non-fired bricks can not only solve the problem of waste disposal but also reduce the production cost of building materials.

[0003] However, existing technologies for non-fired bricks based on construction waste still have some shortcomings. For example, the composition of construction waste is complex, and waste from different sources may contain different impurities, which poses a challenge to the quality stability of non-fired bricks. Furthermore, how to further improve the utilization rate of construction waste while ensuring the high strength and low water absorption of non-fired bricks is also a current research focus. In conclusion, developing a high-strength, environmentally friendly non-fired brick based on construction waste and its preparation method will not only help solve the problem of construction waste disposal but also promote the sustainable development of the building materials industry, thus having significant economic and social implications.

[0004] Chinese invention patent CN110835245A discloses a non-fired brick and its preparation method. The preparation method includes the following steps: adding coagulant and coagulant aid to sewage sludge from a pipeline network, stirring to concentrate it, and then dewatering and air-drying it to obtain dewatered sludge with a weight moisture content of 25-35%; removing impurities from construction waste through a sorting process, and then crushing and screening it to obtain recycled fine aggregate with a particle size of 0-4.75mm; mixing the dewatered sludge (25-40%), recycled fine aggregate (30-45%), blast furnace slag (5-15%), steel slag (5-15%), and cementitious material (9-13%) by weight, adding water, and stirring to obtain a slurry; pouring the slurry into a mold and pressing it into shape; and curing it for at least 28 days after demolding to obtain non-fired bricks. These non-fired bricks have good water absorption, but their compressive strength is relatively poor. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a slag-based non-fired brick and its preparation method.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A type of slag-based non-fired brick comprises the following raw materials in parts by weight:

[0008] Construction waste: 80-100 parts

[0009] Cement: 10-12 parts

[0010] Deionized water: 30-50 parts

[0011] Alkali activator: 10-12 parts

[0012] Defoamer: 1-2 parts

[0013] Basalt fiber: 1-3 parts

[0014] Hardener: 5-10 parts;

[0015] The curing agent is prepared by the following method:

[0016] S1: Phenyltrichlorosilane was slowly added to a tetrahydrofuran solution of magnesium chloropropene under ice bath conditions and reacted for 20-24 hours to obtain trienyl (phenyl)silane.

[0017] S2: Under nitrogen protection, DMF and triallenyl (phenyl)silane are stirred and mixed evenly, heated to 95-105℃, and 1,5-pentanediol, catalyst C-94, and 1-butyl-3-methylimidazolium methane sulfonate ionic liquid are added in sequence. The reaction is carried out for 3-4 hours to obtain hyperbranched organosilicon resin.

[0018] S3: Under nitrogen protection, DMSO, hyperbranched silicone resin and epoxy resin are stirred and mixed evenly, heated to 50-60℃, and phosphoric acid is added and reacted for 2-4 hours to obtain hyperbranched silicone modified epoxy resin.

[0019] S4: Mix DMF, hyperbranched silicone-modified epoxy resin and γ-aminopropyltriethoxysilane thoroughly, and heat to 80-120℃ for 4-6 hours to obtain the curing agent.

[0020] In step S1, the molar ratio of magnesium chloropropene to phenyltrichlorosilane is (3.2-4):1.

[0021] In step S1, the concentration of the magnesium chloropropene tetrahydrofuran solution is 0.5-1.2 mol / L.

[0022] In step S2, the mass ratio of the feed of trienyl (phenyl)silane, 1,5-pentanediol, catalyst C-94, and 1-butyl-3-methylimidazolium methane sulfonate ionic liquid is (6-8):(10-16):(0.6-0.8):(0.8-1).

[0023] In step S3, the mass ratio of DMSO, hyperbranched silicone resin, and epoxy resin is 100:(8-10):(12-14).

[0024] The concentration of phosphoric acid in step S3 is 75-85 wt%.

[0025] In step S4, the mass ratio of DMF, hyperbranched organosilicon-modified epoxy resin, and γ-aminopropyltriethoxysilane is 100:(12-20):(4-6).

[0026] The alkaline activator is one of sodium silicate, sodium carbonate, and potassium sulfate.

[0027] The defoamer is one of sodium dodecyl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, and sodium fatty acid methyl ester sulfonate.

[0028] A method for preparing slag-based non-fired bricks includes the following steps:

[0029] (1) Weigh by weight: engineering waste soil: 80-100 parts, cement: 10-12 parts, deionized water: 30-50 parts, alkali activator: 10-12 parts, defoamer: 1-2 parts, basalt fiber: 1-3 parts, curing agent: 5-10 parts;

[0030] (2) The engineering waste soil is screened to remove impurities such as steel wire and plastic. It is crushed into fine powder with a particle size ≤0.1mm using a crusher. Cement and alkali activator are added and mixed evenly. Then, curing agent, defoamer, basalt fiber and deionized water are added and mixed. The mixed material is spread in a mold and the mold is placed in a press machine for vibration pressing to obtain a semi-finished product of non-fired brick. The semi-finished product of non-fired brick is steam cured at 60-90℃ and humidity ≥95% for 12-24h. Then it is cured at room temperature to obtain waste soil-based non-fired brick.

[0031] Due to the adoption of the above technical solutions, the beneficial effects of the present invention include:

[0032] (1) In this invention, a trienyl (phenyl)silane is obtained by reacting magnesium chloropropene and phenyltrichlorosilane; a hyperbranched organosilicon resin is obtained by reacting trienyl (phenyl)silane with 1,5-pentanediol; then the hyperbranched organosilicon modified epoxy resin is grafted onto epoxy resin; and finally a curing agent is obtained by grafting γ-aminopropyltriethoxysilane.

[0033] (2) The present invention uses industrial slag to replace natural raw materials to process non-fired bricks, which reduces the pollution of the environment caused by waste, reduces the exploitation of natural resources, saves energy, and reduces the production cost of non-fired bricks.

[0034] (3) The curing agent prepared in this invention introduces flexible Si-O bonds. The Si-O bonds can make the polymer chain segments rotate more easily, which can reduce the internal stress of the resin and thus improve the fracture toughness of the resin, so that the prepared non-fired bricks have good mechanical strength.

[0035] (4) The curing agent prepared in this invention has a dendritic structure of hyperbranched organosilicon. The three-dimensional network structure of hyperbranched organosilicon forms high-density cross-linking points through multifunctional group cross-linking, which enhances the rigidity and toughness of epoxy resin and improves the compressive strength and flexural strength of non-fired bricks. The hyperbranched structure can uniformly disperse stress and reduce internal cracks. At the same time, the hyperbranched structure can close pores, reduce water vapor penetration paths, reduce water absorption rate, and extend freeze-thaw cycle life. Detailed Implementation

[0036] The following description, in conjunction with specific embodiments, provides further details, but the present invention is not limited to these embodiments.

[0037] Example 1: Preparation of curing agent:

[0038] S1: Under ice bath conditions, 0.1 mol of phenyltrichlorosilane was slowly added dropwise to 630 ml of 0.5 mol / L tetrahydrofuran solution over 40 min. After reacting for 20 h, 200 ml of saturated ammonium chloride solution was added, mixed thoroughly, and allowed to stand at 0 °C for phase separation. The organic phase was dried over 50 g of anhydrous sodium sulfate for 2 h and then distilled under reduced pressure at 70 °C for 3 h to obtain trienyl (phenyl)silane. The reaction equation is shown below:

[0039] .

[0040] S2: Under nitrogen protection, 500g DMF and 60g trialnyl (phenyl)silane were added to the reactor, stirred, and heated to 95℃. Then, 100g of 1,5-pentanediol (20g per batch, 20min interval between batches) was added in batches, followed by 6g of catalyst C-94 and 8g of 1-butyl-3-methylimidazolium methanesulfonate ionic liquid. After reacting for 4h, the mixture was cooled to room temperature, 400g of deionized water was added, stirred evenly, centrifuged and filtered, then washed with 100g of anhydrous ethanol and then with 100g of deionized water. The mixture was then vacuum dried at 50℃ for 5h to obtain hyperbranched organosilicon resin. The reaction equation is shown below:

[0041] .

[0042] S3: Under nitrogen protection, 1000g DMSO, 80g hyperbranched silicone resin, and 120g epoxy resin were added to a reactor, stirred and mixed, heated to 50℃, and then 20g 75wt% phosphoric acid was added. After reacting for 4 hours, the mixture was rotary evaporated at 40℃ for 3 hours, and then recrystallized three times with acetone (300g acetone each time). The mixture was then vacuum dried at 60℃ for 4 hours to obtain hyperbranched silicone-modified epoxy resin. During this reaction, the hydroxyl groups on the hyperbranched silicone resin react with the epoxy groups on the epoxy resin. When the epoxy resin is grafted onto the hyperbranched silicone resin through epoxy groups, some epoxy resins react with the hyperbranched silicone resin through one epoxy group, while others react with both epoxy groups.

[0043] S4: Add 1000g DMF, 120g hyperbranched silicone-modified epoxy resin, and 40g γ-aminopropyltriethoxysilane sequentially to the reactor. Stir, heat to 80℃, react for 6 hours, cool to 40℃, add 300g triethylamine for neutralization, distill under reduced pressure at 50℃ for 3 hours, and dry under vacuum at 60℃ for 3 hours to obtain the curing agent. This reaction involves the reaction of the epoxy groups on the hyperbranched silicone-modified epoxy resin with the amino groups of γ-aminopropyltriethoxysilane. The structural formula of the product is shown below:

[0044] .

[0045] in represent:

[0046] ;

[0047] n is a natural number.

[0048] It should be noted that the reaction processes of hyperbranching and grafting are quite complex. The above structures are only used to understand the reaction sites in this application and are used to illustrate the reaction sites between the epoxy group and the amino group in step S4.

[0049] Example 2: Preparation of curing agent:

[0050] S1: Under ice bath conditions, 0.12 mol of phenyltrichlorosilane was slowly added dropwise to 520 ml of 0.8 mol / L tetrahydrofuran solution for 40 min. After reacting for 22 h, 250 ml of saturated ammonium chloride solution was added, mixed well, and allowed to stand at 0 °C to separate into layers. The organic phase was dried with 50 g of anhydrous sodium sulfate for 2 h and then distilled under reduced pressure at 70 °C for 3 h to obtain trienyl (phenyl)silane.

[0051] S2: Under nitrogen protection, 500g DMF and 70g trialenyl (phenyl)silane were added to the reactor, stirred, and heated to 100℃. Then, 130g 1,5-pentanediol (10g per batch, 10min interval between batches) was added in batches. Then, 7g catalyst C-94 and 9g 1-butyl-3-methylimidazolium methane sulfonate ionic liquid were added in sequence. After reacting for 3.5h, the mixture was cooled to room temperature, 400g deionized water was added and stirred evenly. The mixture was centrifuged and filtered, then washed with 100g anhydrous ethanol and then washed with 100g deionized water. The mixture was then vacuum dried at 60℃ for 4h to obtain hyperbranched organosilicon resin.

[0052] S3: Under nitrogen protection, 1000g DMSO, 90g hyperbranched silicone resin and 130g epoxy resin were added to the reactor, stirred and mixed, heated to 55℃, and then 20g 80wt% phosphoric acid was added. After reacting for 3h, the mixture was rotary evaporated at 50℃ for 2h, and then recrystallized three times with acetone (300g acetone each time). The mixture was then vacuum dried at 70℃ for 3h to obtain hyperbranched silicone modified epoxy resin.

[0053] S4: Add 1000g DMF, 160g hyperbranched silicone-modified epoxy resin and 50g γ-aminopropyltriethoxysilane sequentially to the reactor, stir, heat to 100℃, react for 5h, cool to 40℃, add 300g triethylamine to neutralize, distill under reduced pressure at 60℃ for 2h, and vacuum dry at 70℃ for 2h to obtain the curing agent.

[0054] Example 3: Preparation of curing agent:

[0055] S1: Under ice bath conditions, 0.16 mol of phenyltrichlorosilane was slowly added dropwise to 530 ml of 1.2 mol / L tetrahydrofuran solution for 40 min. After reacting for 24 h, 250 ml of saturated ammonium chloride solution was added, mixed well, and allowed to stand at 0 °C to separate into layers. The organic phase was dried with 50 g of anhydrous sodium sulfate for 2 h and then distilled under reduced pressure at 70 °C for 3 h to obtain trienyl (phenyl)silane.

[0056] S2: Under nitrogen protection, 500g DMF and 80g trialenyl (phenyl)silane were added to the reactor, stirred, and heated to 105℃. Then, 160g 1,5-pentanediol (20g per batch, 10min interval between batches) was added in batches. Then, 8g catalyst C-94 and 10g 1-butyl-3-methylimidazolium methane sulfonate ionic liquid were added in sequence. After reacting for 3h, the mixture was cooled to room temperature, 400g deionized water was added and stirred evenly. The mixture was centrifuged and filtered, then washed with 100g anhydrous ethanol and then washed with 100g deionized water. The mixture was then vacuum dried at 70℃ for 3h to obtain hyperbranched organosilicon resin.

[0057] S3: Under nitrogen protection, 1000g DMSO, 100g hyperbranched silicone resin and 140g epoxy resin were added to the reactor, stirred and mixed, heated to 60℃, and then 20g 85wt% phosphoric acid was added. After reacting for 2 hours, the mixture was rotary evaporated at 60℃ for 1 hour, and then recrystallized three times with acetone (300g acetone each time). The mixture was then vacuum dried at 80℃ for 2 hours to obtain hyperbranched silicone modified epoxy resin.

[0058] S4: Add 1000g DMF, 200g hyperbranched organosilicon-modified epoxy resin and 60g γ-aminopropyltriethoxysilane sequentially to the reactor, stir, heat to 120℃, react for 4h, cool to 40℃, add 300g triethylamine to neutralize, distill under reduced pressure at 70℃ for 1h, and vacuum dry at 80℃ for 1h to obtain the curing agent.

[0059] Example 4: Preparation of slag-based non-fired bricks:

[0060] (1) Weigh out: 800g of engineering waste soil, 100g of cement, 300g of deionized water, 100g of alkali activator (sodium silicate, modulus 1.2), 10g of defoamer (sodium dodecyl sulfate), 10g of basalt fiber, and 50g of curing agent (prepared in Example 1);

[0061] (2) The engineering waste soil is sieved (5mm aperture) to remove impurities such as steel wire and plastic. It is crushed into fine powder with a particle size ≤0.1mm using a crusher. Cement and alkali activator are added and mixed evenly. The mixture is stirred for 20 minutes at a stirring speed of 200r / min. Then, curing agent, defoamer, basalt fiber and deionized water are added and mixed for 10 minutes at a stirring speed of 300r / min. The mixed material is spread in a mold and placed in a press for vibration pressing. The pressure is 20MPa, the pressing time is 10s, and the vibration frequency is 60Hz to obtain a semi-finished product of non-fired bricks. The semi-finished product of non-fired bricks is steam cured at 60℃ and 98% humidity for 24h. Then, it is cured at room temperature for 7 days to obtain a waste soil-based non-fired brick with a size of 200mm×100mm×60mm.

[0062] Example 5: Preparation of slag-based non-fired bricks:

[0063] (1) Weigh out: 900g of engineering waste soil, 110g of cement, 400g of deionized water, 110g of alkali activator (sodium silicate, modulus 1.2), 150g of defoamer (sodium fatty alcohol polyoxyethylene ether sulfate), 20g of basalt fiber, and 80g of curing agent (prepared in Example 2);

[0064] (2) The engineering waste soil is sieved (5mm aperture) to remove impurities such as steel wire and plastic. It is crushed into fine powder with a particle size ≤0.1mm using a crusher. Cement and alkali activator are added and mixed evenly. The mixture is stirred for 20 minutes at a stirring speed of 200r / min. Then, curing agent, defoamer, basalt fiber and deionized water are added and mixed for 10 minutes at a stirring speed of 300r / min. The mixed material is spread in a mold and placed in a press for vibration pressing. The pressure is 20MPa, the pressing time is 10s, and the vibration frequency is 60Hz to obtain a semi-finished product of non-fired bricks. The semi-finished product of non-fired bricks is steam cured at 80℃ and 95% humidity for 18h. Then, it is cured at room temperature for 7 days to obtain a slag-based non-fired brick with a size of 200mm×100mm×60mm.

[0065] Example 6: Preparation of slag-based non-fired bricks:

[0066] (1) Weigh out: 1000g of engineering waste soil, 120g of cement, 500g of deionized water, 120g of alkali activator (sodium carbonate), 20g of defoamer (sodium methyl ester sulfonate of fatty acids), 30g of basalt fiber, and 100g of curing agent (prepared in Example 3).

[0067] (2) The engineering slag is sieved (5mm aperture) to remove impurities such as steel wire and plastic. It is crushed into fine powder with a particle size ≤0.1mm using a crusher. Cement and alkali activator are added and mixed evenly. The mixture is stirred for 20 minutes at a stirring speed of 200r / min. Then, curing agent, defoamer, basalt fiber and deionized water are added and mixed for 10 minutes at a stirring speed of 300r / min. The mixed material is spread in a mold and placed in a press for vibration pressing. The pressure is 20MPa, the pressing time is 10s, and the vibration frequency is 60Hz to obtain a semi-finished product of non-fired bricks. The semi-finished product of non-fired bricks is steam cured at 90℃ and 95% humidity for 12h. Then, it is cured at room temperature for 7 days to obtain slag-based non-fired bricks with a size of 200mm×100mm×60mm.

[0068] Comparative Example 1

[0069] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5, except that no curing agent is added to the components.

[0070] Comparative Example 2

[0071] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5. The difference is that the curing agent added to the components is replaced with an equal weight of epoxy curing agent.

[0072] Comparative Example 3

[0073] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5. The difference is that the curing agent added to the components is replaced with an equal weight of the hyperbranched organosilicon modified epoxy resin prepared in step S3.

[0074] Comparative Example 4

[0075] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5, except that the curing agent added to the components is replaced with a curing agent prepared by the following method:

[0076] The preparation method of the comparative curing agent is basically the same as that of Example 2, except that the phenyltrichlorosilane in step S1 is replaced with 0.25 mol of triethylvinylsilane.

[0077] Comparative Example 5

[0078] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5, except that the curing agent added to the components is replaced with a curing agent prepared by the following method:

[0079] The preparation method of the comparative curing agent is basically the same as that of Example 2, except that the phenyltrichlorosilane in step S1 is replaced with 0.25 mol of triphenylvinylsilane.

[0080] Comparative Example 6

[0081] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5, except that the curing agent added to the components is replaced with a curing agent prepared by the following method:

[0082] The preparation method of the comparative curing agent is basically the same as that of Example 2, except that the 130g of 1,5-pentanediol added in step S2 is replaced with 70g of 1,5-pentanediol.

[0083] Comparative Example 7

[0084] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5, except that the curing agent added to the components is replaced with a curing agent prepared by the following method:

[0085] The preparation method of the comparative curing agent is basically the same as that of Example 2, except that the 130g of 1,5-pentanediol added in step S2 is replaced with 130g of 1,2-propanediol.

[0086] Comparative Example 8

[0087] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5, except that the curing agent added to the components is replaced with a curing agent prepared by the following method:

[0088] The preparation method of the comparative curing agent is basically the same as that of Example 2, except that the 50g of γ-aminopropyltriethoxysilane added in step S4 is replaced with 50g of (3-aminopropyl)dimethylethoxysilane.

[0089] Comparative Example 9

[0090] The raw material composition and process of the slag-based non-fired bricks are basically the same as those in Example 5. The difference is that the 80g of curing agent (prepared in Example 2) added to the components is changed to 30g.

[0091] Comparative Example 10

[0092] Non-fired bricks made using the raw material composition and process of Chinese Invention Patent Example 2 with publication number CN110835245A.

[0093] The main components of the engineering waste soil used in the embodiments and comparative examples of this application are: crushed concrete blocks: 41.6%, bricks and tiles: 23.5wt%, ceramic fragments: 15.1wt%, crushed stone: 10.4wt%, lime: 6.2wt%, with a moisture content of ≤5%; the cement is road silicate cement grade 42.5 (code P.R7.5), purchased from Shanxi Zhuoyue Cement Co., Ltd.; the basalt fiber length is 1-3mm, purchased from Shandong Oude Chemical Fiber Products Co., Ltd.; the epoxy resin is model E-51; the epoxy curing agent is model HMA-2300, purchased from Complex High-Tech Materials (Shanghai) Co., Ltd.

[0094] The compressive strength, flexural strength, and water absorption properties of the slag-based non-fired bricks prepared in Examples 4-6 and Comparative Examples 1-10 of this application were tested, and the test results are shown in Table 1.

[0095] According to GB / T2542-2012 "Test Methods for Masonry Bricks", compressive strength, flexural strength and water absorption rate tests were conducted.

[0096] Table 1 Performance Test Table

[0097]

[0098] As can be seen from Table 1, the slag-based non-fired bricks prepared in Examples 4-6 of this application have excellent compressive strength, flexural strength and water absorption.

[0099] Comparative Example 1 is a comparative example prepared without adding a curing agent. As can be seen from the data in Table 1, its compressive strength is 9.1 MPa, its flexural strength is 2.72 MPa, and its water absorption rate is 10.5%, which are relatively poor.

[0100] In Comparative Example 2, the curing agent was replaced with an equal weight of epoxy curing agent. As can be seen from Table 1, its compressive strength was 15.3 MPa, its flexural strength was 3.65 MPa, and its water absorption rate was 9.3%, indicating that the mechanical strength of the non-fired bricks prepared by commercially available epoxy curing agents is not as good as that of this application.

[0101] In Comparative Example 3, the curing agent was replaced with the hyperbranched organosilicon-modified epoxy resin prepared in step S3. As shown in Table 1, its compressive strength was 16.4 MPa, its flexural strength was 4.18 MPa, and its water absorption rate was 8.8%. This is because the curing agent grafted with γ-aminopropyltriethoxysilane contains Si-O-Si bonds, which can provide hydrophobicity and chemical corrosion resistance, reduce the brick pulverization caused by the migration of metal ions in the slag. At the same time, the amino group of γ-aminopropyltriethoxysilane reacts with the epoxy group to form a chemical bond. The silanol (-Si-OH) generated after the ethoxy group is hydrolyzed combines with inorganic aggregates (such as slag particles), enhances the organic-inorganic interface bonding force, reduces internal cracks, and thus improves the compressive strength.

[0102] Comparative Examples 4 and 5 replaced the trienyl (phenyl)silane prepared in step S1 of the curing agent preparation process with triethylvinylsilane and triphenylvinylsilane, respectively. As can be seen from Table 1, the compressive strength and water absorption rate are not as good as those of this application. This is because the curing agents prepared by triethylvinylsilane and triphenylvinylsilane have low hyperbranched structures, while the curing agent prepared in this application has a dendritic structure of hyperbranched organosilicon. The three-dimensional network structure of hyperbranched organosilicon forms high-density cross-linking points through multifunctional group cross-linking, which synergistically enhances the rigidity and toughness of epoxy resin, improves the compressive strength and flexural strength of the non-fired brick, and the hyperbranched structure can uniformly disperse stress and reduce internal cracks; the hyperbranched structure closes pores, reduces water vapor penetration paths, reduces water absorption rate, and improves freeze-thaw cycle life; the epoxy resin with low branching structure has fewer cross-linking points, poorer compressive strength, and uneven stress dispersion, which makes it prone to cracking due to interface peeling.

[0103] In Comparative Example 6, the addition method of 1,5-pentanediol in step S2 of the curing agent preparation process is different. In Comparative Example 7, 1,5-pentanediol in step S2 of the curing agent preparation process is replaced with 1,2-propanediol. As can be seen from Table 1, the compressive strength and water absorption rate are not as good as those of this application.

[0104] In Comparative Example 8, γ-aminopropyltriethoxysilane in step S4 of the curing agent preparation process was replaced with (3-aminopropyl)dimethylethoxysilane. As can be seen from Table 1, its compressive strength is 20.3 MPa, its flexural strength is 4.80 MPa, and its water absorption rate is 7.3%.

[0105] Comparative Example 9 is a comparative example different from Example 5, the difference being the amount of curing agent added. As can be seen from Table 1, its compressive strength is 18.6 MPa, its flexural strength is 4.69 MPa, and its water absorption rate is 6.9%, indicating that the addition of curing agent also has a certain impact on the performance of the non-fired bricks.

[0106] Comparative Example 10 is a non-fired brick made using the raw material composition and process of Example 2 of Chinese Invention Patent Publication No. CN110835245A. Its compressive strength and water absorption rate are not as good as the non-fired brick prepared in this application.

[0107] The room temperature curing time for the slag-based non-fired bricks prepared in Example 5 was 7 days. Table 2 shows the performance test results of the slag-based non-fired bricks prepared with different room temperature curing times (other process conditions remained unchanged).

[0108] Table 2. Performance data of slag-based non-fired bricks prepared with different room temperature curing times.

[0109]

[0110] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. However, any modifications, alterations, and variations made by those skilled in the art without departing from the scope of the present invention based on the disclosed technical content are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. A type of slag-based non-fired brick, characterized in that, The ingredients include the following parts by weight: Construction waste: 80-100 parts Cement: 10-12 parts Deionized water: 30-50 parts Alkali activator: 10-12 parts Defoamer: 1-2 parts Basalt fiber: 1-3 parts Hardener: 5-10 parts; The curing agent is prepared by the following method: S1: Phenyltrichlorosilane was slowly added to a tetrahydrofuran solution of magnesium chloropropene under ice bath conditions and reacted for 20-24 hours to obtain trienyl (phenyl)silane. S2: Under nitrogen protection, DMF and triallenyl (phenyl)silane are stirred and mixed evenly, heated to 95-105℃, and 1,5-pentanediol, catalyst C-94, and 1-butyl-3-methylimidazolium methane sulfonate ionic liquid are added in sequence. The reaction is carried out for 3-4 hours to obtain hyperbranched organosilicon resin. S3: Under nitrogen protection, DMSO, hyperbranched silicone resin and epoxy resin are stirred and mixed evenly, heated to 50-60℃, and phosphoric acid is added and reacted for 2-4 hours to obtain hyperbranched silicone modified epoxy resin. S4: Mix DMF, hyperbranched silicone-modified epoxy resin and γ-aminopropyltriethoxysilane thoroughly, and heat to 80-120℃ for 4-6 hours to obtain the curing agent.

2. The slag-based non-fired brick according to claim 1, characterized in that, In step S1, the molar ratio of magnesium chloropropene to phenyltrichlorosilane is (3.2-4):

1.

3. The slag-based non-fired brick according to claim 1, characterized in that, In step S1, the concentration of the magnesium chloropropene tetrahydrofuran solution is 0.5-1.2 mol / L.

4. The slag-based non-fired brick according to claim 1, characterized in that, In step S2, the mass ratio of the feed of trienyl (phenyl)silane, 1,5-pentanediol, catalyst C-94, and 1-butyl-3-methylimidazolium methane sulfonate ionic liquid is (6-8):(10-16):(0.6-0.8):(0.8-1).

5. The slag-based non-fired brick according to claim 1, characterized in that, In step S3, the mass ratio of DMSO, hyperbranched silicone resin, and epoxy resin is 100:(8-10):(12-14).

6. The slag-based non-fired brick according to claim 1, characterized in that, The concentration of phosphoric acid in step S3 is 75-85 wt%.

7. The slag-based non-fired brick according to claim 1, characterized in that, In step S4, the mass ratio of DMF, hyperbranched organosilicon-modified epoxy resin, and γ-aminopropyltriethoxysilane is 100:(12-20):(4-6).

8. The slag-based non-fired brick according to claim 1, characterized in that, The alkaline activator is one of sodium silicate and sodium carbonate.

9. The slag-based non-fired brick according to claim 1, characterized in that, The defoamer is one of sodium dodecyl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, and sodium fatty acid methyl ester sulfonate.

10. A method for preparing slag-based non-fired bricks according to any one of claims 1-9, characterized in that, Includes the following steps: (1) Weigh by weight: engineering waste soil: 80-100 parts, cement: 10-12 parts, deionized water: 30-50 parts, alkali activator: 10-12 parts, defoamer: 1-2 parts, basalt fiber: 1-3 parts, curing agent: 5-10 parts; (2) The engineering waste soil is screened to remove impurities such as steel wire and plastic. It is crushed into fine powder with a particle size ≤0.1mm using a crusher. Cement and alkali activator are added and mixed evenly. Then, curing agent, defoamer, basalt fiber and deionized water are added and mixed. The mixed material is spread in a mold and the mold is placed in a press machine for vibration pressing to obtain a semi-finished product of non-fired brick. The semi-finished product of non-fired brick is steam cured at 60-90℃ and humidity ≥95% for 12-24h. Then it is cured at room temperature to obtain waste soil-based non-fired brick.

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