Anti-corrosion and erosion-resistant high-strength mortar and preparation method thereof

Abstract

The present invention relates to an anti-corrosion and erosion-resistant high-strength mortar and a preparation method thereof. The mortar comprises, by weight, 80-120 parts of cement, 20-30 parts of quartz sand, 10-25 parts of modified bentonite, 10-20 parts of composite fiber, 6-12 parts of preservative, 5-10 parts of acrylic emulsion, 5-10 parts of water reducer, 3-6 parts of coupling agent, and 30-60 parts of water; the modified bentonite is prepared by modifying the bentonite with a 1-10wt% dilute acid solution and a 10-20wt% aluminum sulfate solution; the preservative is prepared by mixing 5-10 parts of mixture A, 10-20 parts of PTB emulsion, and 5-10 parts of deionized water, wherein the mixture A is prepared by mixing 5-10 parts of potassium dihydrogen phosphate, 5-10 parts of dead-burned magnesium oxide powder, 3-6 parts of aluminum zinc tripolyphosphate, and 2-4 parts of borax. The antiseptic prepared by the present invention is interspersed in the modified bentonite sheet and is more tightly combined with silicate cement under the action of acrylic emulsion and coupling agent, thereby enhancing its antiseptic property, especially preventing erosion by acidic water, and having strong weather resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of building materials, and in particular to an anti-corrosion and erosion-resistant high-strength mortar and a preparation method thereof. Background Art

[0002] Mortar is the bonding material used for bricklaying in construction. It is composed of a certain proportion of sand and a binder (cement, lime paste, clay, etc.) mixed with water. It is also called mortar or screed. Common mortars include cement mortar, mixed mortar (also called cement-lime mortar), lime mortar, and clay mortar. Existing cement mortars are prone to corrosion damage after prolonged use in areas frequently subject to water erosion, such as riverbanks and dams, resulting in undesirable problems such as breakage, cracking, and shedding. Specifically, cement undergoes a chemical reaction immediately after mixing with water, producing hydration products such as CSH gel, ettringite (AFt), calcium hydroxide (CH), and calcium aluminate hydrate (CAH). These substances require an alkaline environment. When the pH value of the environment falls below a certain value, the various cement hydration products decompose, causing degradation of the cement-based material's performance. Therefore, acidic environments can easily corrode and damage cement-based materials. As river water pollution is a common phenomenon, the water often contains excessive organic and inorganic acids, which will continuously erode cement mortar, causing loss and posing safety hazards. Therefore, cement mortar has high requirements for corrosion resistance and erosion resistance.

[0003] Chinese patent CN108546024A discloses a corrosion-resistant graphene cement mortar and its preparation method. This method is to load graphene between the layers of bentonite powder, then mix it with cement, sand, coarse aggregate, water, and a water reducer to form a cement mortar, and spray a cationic polyelectrolyte solution to produce the corrosion-resistant graphene cement mortar. Compared with traditional methods, the cement mortar prepared by this method has good dispersion of graphene in the cement mortar, and the cement mortar product has good corrosion resistance and mechanical properties. However, the above technical solution requires the addition of more than 1% by mass of graphene, and the high cost of graphene prevents large-scale application, limiting its promotion. Therefore, it is necessary to develop a new, low-cost cement mortar. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: the present invention provides an anti-corrosion and erosion-resistant high-strength mortar and a preparation method thereof, which has excellent corrosion resistance, erosion resistance and mechanical properties, and at the same time has low manufacturing cost and is suitable for large-scale production.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] The present invention provides an anti-corrosion and anti-erosion high-strength mortar, comprising, by weight:

[0007] 80-120 parts of cement, 20-30 parts of quartz sand, 10-25 parts of modified bentonite, 10-20 parts of composite fiber, 6-12 parts of preservative, 5-10 parts of acrylic emulsion, 5-10 parts of water reducer, 3-6 parts of coupling agent, 30-60 parts of water;

[0008] The modified bentonite is prepared by modifying bentonite with 1-10 wt% dilute acid solution and 10-20 wt% aluminum sulfate solution;

[0009] The preservative is prepared by mixing 5-10 parts of mixed material A, 10-20 parts of PTB emulsion and 5-10 parts of deionized water, wherein the mixed material A is prepared by mixing 5-10 parts of potassium dihydrogen phosphate, 5-10 parts of dead-burned magnesium oxide powder, 3-6 parts of aluminum zinc tripolyphosphate and 2-4 parts of borax.

[0010] The PTB emulsion contained in the preservative of the present invention is a special organic binder. When the base material expands or contracts, the mortar containing the PTB emulsion can deform along with the base in most cases. Even under water pressure, the PTB mortar has excellent bonding properties. The PTB emulsion itself has good corrosion resistance and a small contact angle, and can be well dispersed and cross-linked with the inorganic preservative component composed of dead-burned magnesium oxide powder, aluminum zinc tripolyphosphate, and borax. On the one hand, the pores and interlayer spacing of the bentonite modified with dilute acid and aluminum sulfate solution are increased, which facilitates the PTB emulsion to encapsulate the inorganic preservative and enter the pores of the modified bentonite and intersperse it in the modified bentonite layers. On the other hand, the PTB emulsion has good compatibility with acrylic emulsions and silane coupling agents. Under the action of the two components, the modified bentonite and silicate cement can be more tightly bonded, enhancing the corrosion resistance of the mortar, especially preventing erosion by acidic water and improving weather resistance. Furthermore, the composite fiber added to the mortar forms a bonding layer of organic matrix, silane coupling agent, and inorganic matrix after being combined with the acrylic emulsion and silane coupling agent. This layer bonds more tightly with the inorganic components in the mortar, improving its density, mechanical properties, and corrosion resistance, and extending its service life. Furthermore, the raw materials used in the present invention are readily available, the production cost is low, and the mortar is suitable for waterproof construction projects such as embankments and dams.

[0011] Optionally, the composite fiber is composed of modified basalt fiber and polyimide fiber in a mass ratio of 2-5:1, wherein the modified basalt fiber includes the following raw materials in parts by weight: 50-100 parts of anhydrous ethanol, 10-20 parts of γ-methacryloylpropyltrimethoxysilane and 10-15 parts of bis[3-(triethoxysilyl)propyl]-tetrasulfide.

[0012] Optionally, the acrylic emulsion includes the following raw materials in parts by weight: 50-100 parts of dichloromethane solvent, 10-20 parts of p-methylstyrene, 30-50 parts of ethyl acrylate, 6-12 parts of 4-acetylpyridine, 30-50 parts of 1M sodium benzenesulfonate aqueous solution and 20-40 parts of deionized water.

[0013] Optionally, the cement is po42.5 ordinary portland cement.

[0014] According to the above description, the po42.5 ordinary portland cement used is easy to obtain as raw material and has low preparation cost.

[0015] Optionally, the water reducer is selected from one of lignin sulfonate water reducer, naphthalene water reducer and melamine water reducer.

[0016] According to the above description, water reducer can save cement consumption while maintaining the strength of the system.

[0017] Optionally, the coupling agent is selected from one of the silane coupling agents KH550, KH560, and KH570.

[0018] As described above, the silane alkoxy groups in silane coupling agents are reactive toward inorganic materials, while the organic functional groups are reactive or compatible with organic materials. Therefore, when a silane coupling agent is placed between the inorganic and organic interfaces, it can form a bonding layer of organic matrix-silane coupling agent-inorganic matrix.

[0019] Another aspect of the present invention provides a method for preparing anti-corrosion and erosion-resistant high-strength mortar, the preparation method comprising the following steps:

[0020] S1. Prepare modified bentonite, composite fiber, preservative and acrylic emulsion for standby use;

[0021] S2. Ordinary Portland cement, quartz sand, and modified bentonite are weighed in respective dosages, and ground to obtain a mixture having an average particle size of 50-150 μm;

[0022] S3. Add the prepared composite fiber, preservative, and acrylic emulsion to the mixture obtained above, and add a water reducer and a coupling agent at the same time. Stir and heat at a stirring speed of 200-400 r / min and a heating temperature of 60-80° C. After stirring for 10-20 minutes, stop heating, add water at room temperature, and continue stirring until it cools to 10-30° C. to obtain the anti-corrosion and erosion-resistant high-strength mortar;

[0023] According to the above description, the preparation method of the anti-corrosion and erosion-resistant high-strength mortar has a short process, low equipment requirements and low preparation cost.

[0024] Wherein, the preparation method of the modified bentonite is as follows:

[0025] A1. Add the dilute acid solution to the bentonite and stir the mixture at 60-80°C for 60-120 minutes, wherein the solid-to-liquid ratio of the reaction solution is 1:(2-4);

[0026] A2, after the reaction is completed, filter, dry and crush to obtain raw material A;

[0027] A3, mixing raw material A with aluminum sulfate solution, and stirring the reaction at room temperature for 30-60 min, letting it stand and then filtering and drying to obtain the modified bentonite, wherein the solid-liquid ratio of the reaction solution is 1: (3-6);

[0028] According to the above description, the pore and pore structure of the acid-modified bentonite is improved compared with the original soil. The relatively dense flaky plate stacking structure of the original soil becomes loose and the pores are enlarged. After the bentonite is modified by aluminum sulfate, on the one hand, the interlayer spacing of the bentonite can be enlarged, and on the other hand, the silicon removal rate of the modified bentonite can be improved, making it easier to grind.

[0029] Wherein, the preparation method of the preservative is as follows:

[0030] B1. Mix potassium dihydrogen phosphate, dead-burned magnesium oxide powder, aluminum zinc tripolyphosphate, and borax to obtain a mixture A;

[0031] B2. Mixing the obtained mixed material A with the PTB emulsion and deionized water to obtain the preservative.

[0032] Optionally, the S1 further includes the following steps:

[0033] The composite fiber is prepared by mixing modified basalt fiber and polyimide fiber in a mass ratio of 2-5:1; wherein, the preparation method of the modified basalt fiber is to prepare anhydrous ethanol, γ-methacryloylpropyltrimethoxysilane and bis[3-(triethoxysilyl)propyl]-tetrasulfide into a solution according to a formula, stir evenly, add basalt fiber to soak, dry naturally at room temperature, and then dry to obtain the modified basalt fiber.

[0034] According to the above description, the basalt fiber modified by the above steps reacts more completely and fully with the silane coupling agent under heating conditions.

[0035] Optionally, the S1 further includes the following steps:

[0036] The preparation method of the acrylic emulsion is as follows: p-methylstyrene, ethyl acrylate and 4-acetylpyridine are added to a dichloromethane solvent at 85-95°C to carry out a free radical polymerization reaction to obtain a polymer solution; a 1M sodium benzenesulfonate aqueous solution is added dropwise to the obtained polymer solution under high-speed dispersion for 10-20 minutes; and deionized water is added dropwise for 20-40 minutes; and the mixture is stirred at a pressure of 1×10 2 -1×10 -1 Pa, distill under reduced pressure at a temperature of 35-45°C to remove the solvent.

[0037] According to the above description, the acrylic emulsion prepared by the above method has better weather resistance and water resistance, and can be better cross-linked with the silane coupling agent. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The corrosion resistance test diagram of Examples 1-3 and Comparative Examples 1-4;

[0039] Figure 2 7d flexural strength and 7d compressive strength test graphs of Examples 1-3 and Comparative Examples 1-4;

[0040] Figure 3 These are test graphs of the 28d flexural strength and 28d compressive strength of Examples 1-3 and Comparative Examples 1-4. DETAILED DESCRIPTION

[0041] To better understand the above technical solutions, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. Instead, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0042] Example 1

[0043] An anti-corrosion and anti-erosion high-strength mortar, comprising, by weight:

[0044] 80 parts of ordinary Portland cement, 20 parts of quartz sand, 10 parts of modified bentonite, 10 parts of composite fiber, 6 parts of preservative, 5 parts of acrylic emulsion, 5 parts of lignin sulfonate water reducer, 3 parts of silane coupling agent KH550, and 30 parts of water.

[0045] The modified bentonite is prepared by modifying bentonite with 1 wt% dilute acid solution and 10 wt% aluminum sulfate solution;

[0046] Preferably, the dilute acid solution is oxalic acid solution. Compared with hydrochloric acid and nitric acid, oxalic acid is convenient and safe to store and transport, has less harm to the environment, and its performance still meets the modification requirements;

[0047] The preservative is prepared by mixing 10 parts of mixed material A, 10 parts of PTB emulsion and 5 parts of deionized water, wherein the mixed material A is prepared by mixing 10 parts of potassium dihydrogen phosphate, 5 parts of dead-burned magnesium oxide powder, 3 parts of aluminum zinc tripolyphosphate and 2 parts of borax;

[0048] The composite fiber is composed of modified basalt fiber and polyimide fiber in a mass ratio of 2:1, wherein the modified basalt fiber includes raw materials in parts by weight: 50 parts of anhydrous ethanol, 10 parts of γ-methacryloylpropyltrimethoxysilane and 10 parts of bis[3-(triethoxysilyl)propyl]-tetrasulfide;

[0049] The acrylic emulsion includes the following raw materials in parts by weight: 100 parts of dichloromethane solvent, 10 parts of p-methylstyrene, 30 parts of ethyl acrylate, 6 parts of 4-acetylpyridine, 30 parts of 1M sodium benzenesulfonate aqueous solution and 20 parts of deionized water.

[0050] It is prepared by the following method:

[0051] S1. Prepare modified bentonite, composite fiber, preservative and acrylic emulsion for standby use;

[0052] S2. Ordinary Portland cement, quartz sand, and modified bentonite are weighed in respective dosages, added into a grinder, and ground to obtain a mixture with an average particle size of 50 μm;

[0053] S3. Add the prepared composite fiber, preservative, and acrylic emulsion to the mixture obtained above, and add lignin sulfonate water reducer and silane coupling agent KH550 at the same time, stir and heat at a stirring speed of 200 r / min and a heating temperature of 60° C. After stirring for 10 minutes, stop heating, add water at room temperature, and continue stirring until it cools to 10° C. to obtain the anti-corrosion and erosion-resistant high-strength mortar;

[0054] Wherein, the preparation method of the modified bentonite is as follows:

[0055] A1. Add oxalic acid solution to bentonite and stir at 60°C for 60 minutes. The solid-liquid ratio of the reaction solution is 1:2.

[0056] A2, after the reaction is completed, filter, dry and crush to obtain raw material A;

[0057] A3, mixing raw material A with aluminum sulfate solution, and stirring the reaction at room temperature for 30 minutes, letting it stand and then filtering and drying to obtain the modified bentonite, wherein the solid-liquid ratio of the reaction solution is 1:3;

[0058] Wherein, the preparation method of the preservative is as follows:

[0059] B1. Mix potassium dihydrogen phosphate, dead-burned magnesium oxide powder, aluminum zinc tripolyphosphate, and borax to obtain a mixture A;

[0060] B2. Mixing the obtained mixed material A with the PTB emulsion and deionized water to obtain the preservative.

[0061] Said S1 further comprises the following steps:

[0062] The composite fiber is prepared by mixing modified basalt fiber and polyimide fiber in a mass ratio of 2:1; wherein, the preparation method of the modified basalt fiber is to prepare anhydrous ethanol, γ-methacryloylpropyltrimethoxysilane and bis[3-(triethoxysilyl)propyl]-tetrasulfide into a solution according to a formula, stir evenly, add basalt fiber to soak, dry naturally at room temperature, and then put it into an oven to dry.

[0063] Said S1 further comprises the following steps:

[0064] The preparation method of the acrylic emulsion is as follows: p-methylstyrene, ethyl acrylate and 4-acetylpyridine are added to a dichloromethane solvent at 85°C to carry out a free radical polymerization reaction to obtain a polymer solution; the obtained polymer solution is then transferred to a dispersion kettle; a 1M sodium benzenesulfonate aqueous solution is added dropwise for 10 minutes under high-speed dispersion; and deionized water is then added dropwise for 20 minutes; and the mixture is stirred at a pressure of 1×10 2 -1×10 -1 Pa, the temperature is 35 ℃, and the reduced pressure distillation is carried out to remove the solvent.

[0065] Example 2

[0066] An anti-corrosion and anti-erosion high-strength mortar, comprising, by weight:

[0067] 100 parts of ordinary Portland cement, 25 parts of quartz sand, 20 parts of modified bentonite, 15 parts of composite fiber, 8 parts of preservative, 7 parts of acrylic emulsion, 7 parts of naphthalene-based water reducer, 4 parts of silane coupling agent KH560, and 45 parts of water.

[0068] The modified bentonite is prepared by modifying bentonite with 5wt% oxalic acid solution and 15wt% aluminum sulfate solution;

[0069] The preservative is prepared by mixing 10 parts of mixed material A, 15 parts of PTB emulsion and 7 parts of deionized water, wherein the mixed material A is prepared by mixing 10 parts of potassium dihydrogen phosphate, 8 parts of dead-burned magnesium oxide powder, 5 parts of aluminum zinc tripolyphosphate and 3 parts of borax;

[0070] The composite fiber is composed of modified basalt fiber and polyimide fiber in a mass ratio of 3:1, wherein the modified basalt fiber includes raw materials in parts by weight: 75 parts of anhydrous ethanol, 15 parts of γ-methacryloylpropyltrimethoxysilane and 12 parts of bis[3-(triethoxysilyl)propyl]-tetrasulfide;

[0071] The acrylic emulsion includes the following raw materials in parts by weight: 100 parts of dichloromethane solvent, 15 parts of p-methylstyrene, 40 parts of ethyl acrylate, 8 parts of 4-acetylpyridine, 40 parts of 1M sodium benzenesulfonate aqueous solution and 30 parts of deionized water.

[0072] It is prepared by the following method:

[0073] S1. Prepare modified bentonite, composite fiber, preservative and acrylic emulsion for standby use;

[0074] S2. Ordinary Portland cement, quartz sand, and modified bentonite were weighed in respective dosages, added to a grinder, and ground to obtain a mixture with an average particle size of 100 μm;

[0075] S3, into the above-mentioned mixture obtained, the composite fiber, preservative, and acrylic emulsion prepared in advance were added, and a naphthalene-based water reducer and a silane coupling agent KH560 were added at the same time, and the mixture was stirred and heated at a stirring speed of 300 r / min and a heating temperature of 70 ° C. After stirring for 15 min, the heating was stopped, and water at room temperature was added, and stirring was continued until it cooled to 20 ° C to obtain the anti-corrosion and anti-erosion high-strength mortar;

[0076] Wherein, the preparation method of the modified bentonite is as follows:

[0077] A1. Add oxalic acid solution to bentonite and stir at 70°C for 60 minutes. The solid-liquid ratio of the reaction solution is 1:3.

[0078] A2, after the reaction is completed, filter, dry and crush to obtain raw material A;

[0079] A3, mixing raw material A with aluminum sulfate solution, and stirring the reaction at room temperature for 45 minutes, letting it stand and then filtering and drying to obtain the modified bentonite, wherein the solid-liquid ratio of the reaction solution is 1:4;

[0080] Wherein, the preparation method of the preservative is as follows:

[0081] B1. Mix potassium dihydrogen phosphate, dead-burned magnesium oxide powder, aluminum zinc tripolyphosphate, and borax to obtain a mixture A;

[0082] B2. Mixing the obtained mixed material A with the PTB emulsion and deionized water to obtain the preservative.

[0083] Said S1 further comprises the following steps:

[0084] The composite fiber is prepared by mixing modified basalt fiber and polyimide fiber in a mass ratio of 3:1; wherein, the preparation method of the modified basalt fiber is to prepare anhydrous ethanol, γ-methacryloylpropyltrimethoxysilane and bis[3-(triethoxysilyl)propyl]-tetrasulfide into a solution according to a formula, stir evenly, add basalt fiber to soak, dry naturally at room temperature, and then put it into an oven to dry.

[0085] Said S1 further comprises the following steps:

[0086] The preparation method of the acrylic emulsion is as follows: p-methylstyrene, ethyl acrylate and 4-acetylpyridine are added to a dichloromethane solvent at 90°C to carry out a free radical polymerization reaction to obtain a polymer solution; the obtained polymer solution is then transferred to a dispersion kettle; a 1M sodium benzenesulfonate aqueous solution is added dropwise for 15 minutes under high-speed dispersion; and deionized water is then added dropwise for 30 minutes; and the mixture is stirred at a pressure of 1×10 2 -1×10 -1 Pa, the temperature is 40 ℃ under reduced pressure distillation conditions, and the solvent is removed to obtain the product.

[0087] Example 3

[0088] An anti-corrosion and anti-erosion high-strength mortar, comprising, by weight:

[0089] 120 parts of ordinary Portland cement, 30 parts of quartz sand, 25 parts of modified bentonite, 20 parts of composite fiber, 12 parts of preservative, 10 parts of acrylic emulsion, 10 parts of melamine water reducer, 6 parts of silane coupling agent KH570, and 60 parts of water.

[0090] Wherein, the modified bentonite is prepared by modifying bentonite with 10wt% oxalic acid solution and 20wt% aluminum sulfate solution;

[0091] The preservative is prepared by mixing 10 parts of mixed material A, 20 parts of PTB emulsion and 10 parts of deionized water, wherein the mixed material A is prepared by mixing 10 parts of potassium dihydrogen phosphate, 10 parts of dead-burned magnesium oxide powder, 6 parts of aluminum zinc tripolyphosphate and 4 parts of borax;

[0092] The composite fiber is composed of modified basalt fiber and polyimide fiber in a mass ratio of 5:1, wherein the modified basalt fiber includes raw materials in parts by weight: 100 parts of anhydrous ethanol, 20 parts of γ-methacryloylpropyltrimethoxysilane and 15 parts of bis[3-(triethoxysilyl)propyl]-tetrasulfide;

[0093] The acrylic emulsion includes the following raw materials in parts by weight: 100 parts of dichloromethane solvent, 20 parts of p-methylstyrene, 50 parts of ethyl acrylate, 12 parts of 4-acetylpyridine, 50 parts of 1M sodium benzenesulfonate aqueous solution and 40 parts of deionized water.

[0094] It is prepared by the following method:

[0095] S1. Prepare modified bentonite, composite fiber, preservative and acrylic emulsion for standby use;

[0096] S2. Ordinary Portland cement, quartz sand, and modified bentonite are weighed in respective dosages, added into a grinder, and ground to obtain a mixture with an average particle size of 150 μm;

[0097] S3. Add the prepared composite fiber, preservative, and acrylic emulsion to the mixture obtained above, and add a melamine-based water reducer and a silane coupling agent KH570 at the same time. Stir and heat at a stirring speed of 400 r / min and a heating temperature of 80° C. After stirring for 20 minutes, stop heating, add water at room temperature, and continue stirring until it cools to 30° C. to obtain the anti-corrosion and erosion-resistant high-strength mortar.

[0098] Wherein, the preparation method of the modified bentonite is as follows:

[0099] A1. Add oxalic acid solution to bentonite and stir at 80°C for 120 minutes. The solid-liquid ratio of the reaction solution is 1:4.

[0100] A2, after the reaction is completed, filter, dry and crush to obtain raw material A;

[0101] A3, mixing raw material A with aluminum sulfate solution, and stirring the reaction at room temperature for 60 minutes, letting it stand and then filtering and drying to obtain the modified bentonite, wherein the solid-liquid ratio of the reaction solution is 1:6;

[0102] Wherein, the preparation method of the preservative is as follows:

[0103] B1. Mix potassium dihydrogen phosphate, dead-burned magnesium oxide powder, aluminum zinc tripolyphosphate, and borax to obtain a mixture A;

[0104] B2. Mixing the obtained mixed material A with the PTB emulsion and deionized water to obtain the preservative.

[0105] Said S1 further comprises the following steps:

[0106] The composite fiber is prepared by mixing modified basalt fiber and polyimide fiber in a mass ratio of 5:1; wherein, the preparation method of the modified basalt fiber is to prepare anhydrous ethanol, γ-methacryloylpropyltrimethoxysilane and bis[3-(triethoxysilyl)propyl]-tetrasulfide into a solution according to a formula, stir evenly, add basalt fiber to soak, dry naturally at room temperature, and then put it into an oven to dry.

[0107] Said S1 further comprises the following steps:

[0108] The preparation method of the acrylic emulsion is as follows: p-methylstyrene, ethyl acrylate and 4-acetylpyridine are added to a dichloromethane solvent at 95°C to carry out a free radical polymerization reaction to obtain a polymer solution; the obtained polymer solution is then transferred to a dispersion kettle; a 1M sodium benzenesulfonate aqueous solution is added dropwise for 20 minutes under high-speed dispersion; and deionized water is then added dropwise for 40 minutes; and the mixture is stirred at a pressure of 1×10 2 -1×10 -1 Pa, the temperature is 45 ℃, and the reduced pressure distillation is carried out to remove the solvent.

[0109] Comparative Example 1

[0110] This comparative example differs from Example 2 in that the raw materials do not contain modified bentonite.

[0111] Comparative Example 2

[0112] This comparative example is different from Example 2 in that the raw materials do not contain preservatives.

[0113] Comparative Example 3

[0114] This comparative example is different from Example 2 in that the raw materials do not contain modified bentonite and preservative.

[0115] Comparative Example 4

[0116] This comparative example uses acrylic emulsion cement mortar GT-500 provided by Beijing Ruishengte Building Materials Co., Ltd. for commercial comparison.

[0117] (1) Corrosion resistance test

[0118] Test method: The cement mortar product was made into a standard cubic specimen with a side length of 15 cm, with 2 groups of each embodiment and comparative example, 6 pieces in each group.

[0119] The cement mortar product specimens were taken out, cleaned and dried in a drying oven at 75°C for 16 hours. The initial compressive strength of the cement product specimens was tested using a concrete compressive strength testing machine. Then, one group (6 specimens) were immersed in a 5% salt solution prepared with NaCl, NaNO3, NH4Cl and MgSO4, with a pH value of 7; another group (6 specimens) were immersed in a 5% HCl solution for a period of time; the specimens were taken out at 3 months and 6 months respectively, and the compressive strength was tested after drying. The average value was calculated. The obtained data are shown in Table 1 and Figure 1 shown.

[0120] Table 1 Corrosion resistance test results

[0121]

[0122] From Table 1 and Figure 1 Analysis shows that in Examples 1-3, since modified bentonite and preservatives were added to the mortar at the same time, the compressive strength decreased less after 3-6 months of accelerated immersion in salt solution and acid solution. This shows that the corrosion-resistant and erosion-resistant high-strength mortar prepared by the present invention has excellent corrosion resistance. This is attributed to the preservatives interspersed in the modified bentonite layers. Under the action of acrylic emulsion and coupling agent, they are more tightly bonded to silicate cement, enhancing its corrosion resistance, especially preventing erosion by acidic water, and having strong weather resistance. However, Comparative Example 1, which lacks modified bentonite, Comparative Example 2, which lacks preservatives, and Comparative Example 3, which lacks both ingredients, all showed a significant decrease in compressive strength after 3-6 months of accelerated immersion in salt solution and acid solution, and the mortar prepared in Comparative Example 3 had the worst corrosion resistance, which further illustrates the synergistic effect between the preservative and the modified bentonite. Commercial Comparative Example 4 shows that the corrosion resistance of the existing commercially available ordinary cement mortar after accelerated immersion in salt solution and acid solution for 3-6 months is inferior to that of Examples 1-3.

[0123] (2) Flexural strength and compressive strength test

[0124] The mortars prepared in Examples 1-3 and Comparative Examples 1-4 were tested for performance according to JC / T170-2009 "Standard for Basic Performance Test Methods of Building Mortars". The test results of 7d flexural strength and 7d compressive strength are shown in Tables 2 and 3. Figure 2 The test results of 28d flexural strength and 28d compressive strength are shown in Table 3 and Figure 3 .

[0125] Table 2 7d flexural strength and 7d compressive strength test results

[0126] 7d flexural strength (MPa) 7d compressive strength (MPa) Example 1 2.8 23.5 Example 2 3.1 23.8 Example 3 2.9 24.1 Comparative Example 1 3.1 22.4 Comparative Example 2 2.7 23.4 Comparative Example 3 2.7 21.2 Comparative Example 4 2.3 19.8

[0127] Table 3 28d flexural strength and 28d compressive strength test results

[0128] 28d flexural strength (MPa) 28d compressive strength (MPa) Example 1 4.3 34.3 Example 2 4.5 35.5 Example 3 4.7 37.1 Comparative Example 1 4.2 32.0 Comparative Example 2 4.3 33.5 Comparative Example 3 4.2 31.7 Comparative Example 4 3.9 30.2

[0129] According to the data in Tables 2 and 3, the anti-corrosion and erosion-resistant high-strength mortar prepared in the present invention exhibits relatively excellent flexural strength and compressive strength performance at 7 days and 28 days.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-strength mortar with anti-corrosion and anti-erosion properties, characterized in that: Including by weight: 80-120 parts of cement, 20-30 parts of quartz sand, 10-25 parts of modified bentonite, 10-20 parts of composite fiber, 6-12 parts of preservative, 5-10 parts of acrylic emulsion, 5-10 parts of water reducer, 3-6 parts of coupling agent, 30-60 parts of water; The modified bentonite is prepared by modifying bentonite with 1-10 wt% dilute acid solution and 10-20 wt% aluminum sulfate solution; The preservative is prepared by mixing 5-10 parts of mixed material A, 10-20 parts of PTB emulsion, and 5-10 parts of deionized water, wherein the mixed material A is prepared by mixing 5-10 parts of potassium dihydrogen phosphate, 5-10 parts of dead-burned magnesium oxide powder, 3-6 parts of aluminum zinc tripolyphosphate, and 2-4 parts of borax; The composite fiber is composed of modified basalt fiber and polyimide fiber in a mass ratio of 2-5:

1.

2. The anti-corrosion and erosion-resistant high-strength mortar according to claim 1, characterized in that: The modified basalt fiber comprises the following raw materials in parts by weight: 50-100 parts of anhydrous ethanol, 10-20 parts of gamma-methacryloylpropyltrimethoxysilane and 10-15 parts of bis[3-(triethoxysilyl)propyl]-tetrasulfide.

3. The anti-corrosion and erosion-resistant high-strength mortar according to claim 1, characterized in that: The acrylic emulsion comprises the following raw materials in parts by weight: 50-100 parts of dichloromethane solvent, 10-20 parts of p-methylstyrene, 30-50 parts of ethyl acrylate, 6-12 parts of 4-acetylpyridine, 30-50 parts of 1M sodium benzenesulfonate aqueous solution and 20-40 parts of deionized water.

4. The anti-corrosion and erosion-resistant high-strength mortar according to claim 1, characterized in that: The cement is po42.5 ordinary portland cement.

5. The anti-corrosion and erosion-resistant high-strength mortar according to claim 1, characterized in that: The water reducer is selected from one of lignin sulfonate water reducer, naphthalene water reducer and melamine water reducer.

6. The anti-corrosion and erosion-resistant high-strength mortar according to claim 1, characterized in that: The coupling agent is selected from one of silane coupling agents KH550, KH560, and KH570.

7. A method for preparing the anti-corrosion and anti-erosion high-strength mortar according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: S1, prepare modified bentonite, composite fiber, preservative and acrylic emulsion, set aside; S2. Ordinary Portland cement, quartz sand, and modified bentonite are weighed in respective dosages, and ground to obtain a mixture having an average particle size of 50-150 μm; S3. Add the prepared composite fiber, preservative, and acrylic emulsion to the mixture obtained above, and add a water reducer and a coupling agent at the same time. Stir and heat at a stirring speed of 200-400 r / min and a heating temperature of 60-80° C. After stirring for 10-20 minutes, stop heating, add water at room temperature, and continue stirring until it cools to 10-30° C. to obtain the anti-corrosion and erosion-resistant high-strength mortar; Wherein, the preparation method of the modified bentonite is as follows: A1. Add the dilute acid solution to the bentonite and stir the mixture at 60-80°C for 60-120 minutes. The solid-to-liquid ratio of the reaction solution is 1:(2-4). A2, after the reaction is completed, filter, dry and crush to obtain raw material A; A3, mixing raw material A with aluminum sulfate solution, stirring and reacting at room temperature for 30-60 minutes, letting it stand, filtering, and drying to obtain the modified bentonite, wherein the solid-liquid ratio of the reaction solution is 1:(3-6); Wherein, the preparation method of the preservative is as follows: B1. Mix potassium dihydrogen phosphate, dead-burned magnesium oxide powder, aluminum zinc tripolyphosphate, and borax to obtain a mixture A; B2. Mixing the obtained mixed material A with the PTB emulsion and deionized water to obtain the preservative.

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