An eco-friendly corrosion-resistant cement and its preparation method

Abstract

This invention discloses an eco-friendly corrosion-resistant cement and its preparation method, relating to the field of cement technology. The eco-friendly corrosion-resistant cement comprises the following raw materials in parts by weight: 60-70 parts clinker, 5-10 parts slag, 15-20 parts mineral powder, 15-20 parts fly ash, 5-6 parts gypsum, 3-4 parts silica fume, 2-3 parts corrosion inhibitor, and 1-2 parts water-reducing agent. The eco-friendly corrosion-resistant cement prepared by this invention exhibits good compressive strength, flexural strength, fluidity, and corrosion resistance.

Description

Technical Field

[0001] This invention relates to the field of cement technology, specifically to an eco-friendly corrosion-resistant cement and its preparation method. Background Technology

[0002] Concrete structures such as highway curbs and retaining walls are exposed to the elements for extended periods, making them highly susceptible to durability degradation due to traffic loads and complex natural conditions. Especially in cold or rainy / snowy regions, the de-icing salts frequently used in winter contain high levels of chloride ions. These chloride ions can penetrate the concrete pores, damaging the passivation film on the reinforcing steel and causing corrosion. This leads to cracking and spalling of the concrete cover, significantly reducing the structure's load-bearing capacity and service life. Simultaneously, some road sections have high sulfate content in the soil and groundwater. Sulfates react with cement hydration products to generate expansive substances, easily causing cement stone to expand and microcracks to propagate, ultimately leading to cracking and reduced strength in the concrete structure. Furthermore, vehicle exhaust emissions contain acidic substances such as sulfur dioxide and nitrogen oxides, which, under humid conditions, form an acidic medium that corrodes the concrete surface, accelerating surface pulverization and erosion. Existing conventional cement or anti-corrosion measures mostly rely on external coatings or high-dosage chemical admixtures, which have problems such as insufficient durability and large environmental impact, making it difficult to meet the requirements of highway infrastructure for long-term service, eco-friendliness and comprehensive corrosion resistance.

[0003] Chinese invention patent CN111892341A discloses an anti-corrosion composite cement and its preparation process. The components of the anti-corrosion composite cement include: 500-700 parts of cement clinker, 100-150 parts of modified hydrotalcite, 35-50 parts of modified PVA fiber, 200-300 parts of calcium carbonate, 100-150 parts of fly ash, and 50-100 parts of water-reducing agent. Although the anti-corrosion composite cement prepared by this invention has good corrosion resistance, its flowability needs to be improved. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide an eco-friendly corrosion-resistant cement and its preparation method.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] An eco-friendly corrosion-resistant cement comprises the following raw materials in parts by weight: 60-70 parts clinker, 5-10 parts slag, 15-20 parts mineral powder, 15-20 parts fly ash, 5-6 parts gypsum, 3-4 parts silica fume, 2-3 parts corrosion inhibitor, and 1-2 parts water-reducing agent.

[0007] The corrosion inhibitor is prepared by the following method:

[0008] S1: 2,6-Bis(chloromethyl)-4-methylphenol reacts with methacrylyl chloride to form intermediate 1.

[0009] S2: Intermediate 1 reacts with 3-mercaptopropyltrimethoxysilane to generate intermediate 2.

[0010] S3: 3-Quinoline carbaldehyde reacts with 6-aminohexane phosphoric acid to form intermediate 3.

[0011] S4: Intermediate 2 reacts with intermediate 3 to form a corrosion inhibitor.

[0012] In step S1, the molar ratio of 2,6-bis(chloromethyl)-4-methylphenol to methacryloyl chloride is 1:(1.05-1.1).

[0013] In step S2, the molar ratio of intermediate 1 to 3-mercaptopropyltrimethoxysilane is 1:(1.02-1.05).

[0014] In step S3, the molar ratio of 3-quinoline formaldehyde to 6-aminohexane phosphoric acid is 1:(1.05-1.1).

[0015] In step S4, the molar ratio of intermediate 2 to intermediate 3 is 1:(2.05-2.1).

[0016] The water-reducing agent is prepared by the following method:

[0017] A1: 4-Aminonaphthalene-1,6-disulfonic acid reacts with N,N,N,N,-tetracyclooxypropyl-4,4-diaminodiphenylmethane to form a four-armed compound.

[0018] A2: The four-armed compound reacts with methyl linoleate to generate a long-chain olefin-modified four-armed compound.

[0019] A3: A long-chain olefin-modified four-arm compound reacts with 7-mercaptoheptanoic acid to generate a water-reducing agent.

[0020] In step A1, the molar ratio of 4-aminonaphthalene-1,6-disulfonic acid to N,N,N,N,-tetracyclooxypropyl-4,4-diaminodiphenylmethane is 4.02:1.

[0021] In step A2, the molar ratio of the four-armed compound to methyl linoleate is 1:4.06.

[0022] In step A3, the molar ratio of the long-chain olefin-modified tetra-arm compound to 7-mercaptoheptanoic acid is 1:8.05.

[0023] A method for preparing eco-friendly corrosion-resistant cement includes the following steps:

[0024] (1) Raw material pretreatment: Clinker, slag, mineral powder and fly ash are crushed and sieved;

[0025] (2) Weigh out the following by weight: 60-70 parts clinker, 5-10 parts slag, 15-20 parts mineral powder, 15-20 parts fly ash, 5-6 parts gypsum, 3-4 parts silica fume, 2-3 parts corrosion inhibitor, and 1-2 parts water-reducing agent.

[0026] (3) Put the above raw materials into a mixer and dry mix them to obtain a mixture; send the mixture into a cement mill for grinding to obtain ecological corrosion-resistant cement.

[0027] Due to the adoption of the above technical solutions, the beneficial effects of the present invention include:

[0028] The eco-friendly corrosion-resistant cement prepared by this invention has good compressive strength, flexural strength, fluidity and corrosion resistance. Attached Figure Description

[0029] Figure 1 The 1H NMR spectrum of the corrosion inhibitor prepared in step S4 of Example 1;

[0030] Figure 2 This is a high-resolution mass spectrum of the corrosion inhibitor prepared in step S4 of Example 1;

[0031] Figure 3 The 1H NMR spectrum of the water-reducing agent prepared in step A3 of Example 4;

[0032] Figure 4 This is a high-resolution mass spectrum of the water-reducing agent prepared in step A3 of Example 4. Detailed Implementation

[0033] The following description, in conjunction with specific embodiments, provides further details, but the present invention is not limited to these embodiments.

[0034] Example 1: Preparation of corrosion inhibitor:

[0035] S1: Under nitrogen protection, 200 mL of dichloromethane and 0.1 mol of 2,6-bis(chloromethyl)-4-methylphenol were added to the reaction flask and stirred to dissolve. Then, 1.5 g of catalyst DMAP (4-dimethylaminopyridine), 50 mg of polymerization inhibitor hydroquinone, and 0.12 mol of triethylamine were added and stirred. Under ice bath conditions, 0.105 mol of methacryloyl chloride was slowly added dropwise over 20 min. After the addition was complete, the mixture was heated to reflux and reacted for 2 h. After cooling to room temperature, the reaction solution was slowly poured into 300 mL of ice water. The mixture was separated, and the aqueous phase was extracted three times with dichloromethane (100 mL each time). The organic phases were combined and washed successively with 100 mL of saturated sodium bicarbonate solution, 100 mL of deionized water, and 100 mL of saturated sodium chloride solution. The mixture was dried with 40 g of anhydrous sodium sulfate, filtered, and rotary evaporated at 35 °C for 1 h. The mixture was then vacuum dried at 50 °C for 12 h to obtain intermediate 1. The reaction equation is shown below:

[0036]

[0037] Its 1H NMR spectrum data is as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.18 – 7.09 (m,2H), 5.95 – 5.47 (m, 2H), 4.72 – 4.49 (s, 4H), 2.29 (s, 3H), 2.00 (dd, J =2.4, 1.9 Hz, 3H); HRMS (m / z):273.0375[M+H] + .

[0038] S2: Under nitrogen protection, add 250 ml of anhydrous tetrahydrofuran, 0.1 mol of intermediate 1, 0.102 mol of 3-mercaptopropyltrimethoxysilane, and 0.5 g of photoinitiator 184 to the reaction flask, stir and mix well, and at room temperature, at an intensity of 8.4 mW / cm². 2 After irradiation under a 365nm UV LED lamp for 4 hours, the mixture was rotary evaporated at 40℃ for 1 hour. The solution was then slowly added to 200mL of cold n-hexane, stirred, and a precipitate formed. The precipitate was filtered, washed three times with 50mL of cold n-hexane each time, and dried under vacuum at 40℃ for 12 hours to obtain intermediate 2. The reaction equation is shown below:

[0039]

[0040] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d) δ 7.22 – 7.10 (m,2H), 4.65 – 4.51 (m, 4H), 3.59 (s, 9H), 3.04 – 2.92 (m, 1H), 2.81 – 2.42 (m,4H), 2.29 (s, 3H), 1.65 – 1.51 (m, 2H), 1.25 – 1.16 (m, 3H), 0.79 (t, J = 9.1Hz, 2H); HRMS (m / z): 469.0963[M+H] + .

[0041] S3: Under nitrogen protection, 100 ml of anhydrous tetrahydrofuran, 0.1 mol of 3-quinoline carbaldehyde, and 10 g of 4A molecular sieve (sodium-A type molecular sieve) were added to a reaction flask and stirred until well mixed. Then, 200 ml of a methanol solution containing 0.105 mol of 6-aminohexane phosphoric acid and 0.11 mol of triethylamine was slowly added dropwise over 20 min. After the addition was complete, the mixture was heated to reflux for 6 h, cooled to room temperature, filtered, and the filtrate was distilled under reduced pressure at 40 °C for 1 h. Then, 300 ml of cold n-hexane was added, and the mixture was stirred to precipitate. The precipitate was filtered, washed three times with petroleum ether (50 ml each time), and dried under vacuum at 40 °C for 12 h to obtain intermediate 3. The reaction equation is shown below:

[0042]

[0043] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 8.90 (dd, J =3.7, 1.5 Hz, 1H), 8.56 (tt, J = 2.3, 1.8 Hz, 1H), 8.32 (m, 1H), 7.95 (s, 2H),7.92 – 7.86 (m, 2H), 7.69 – 7.61 (m, 1H), 7.49 (dddd, J = 8.3, 7.8, 4.3, 1.6Hz, 1H), 3.47 (td, J = 6.9, 3.6 Hz, 2H), 1.96 (td, J = 10.0, 4.8 Hz, 2H), 1.76 – 1.54 (m, 4H), 1.48 – 1.35 (m, 4H); HRMS (m / z): 321.1292 [M+H] + .

[0044] S4: Under nitrogen protection, 800 mL of anhydrous acetonitrile, 0.1 mol of intermediate 2, and 0.205 mol of intermediate 3 were added to the reaction flask. The mixture was stirred and stirred until homogeneous. The mixture was heated to reflux and reacted for 12 h. After cooling to room temperature, the mixture was rotary evaporated at 50 °C for 1 h. The precipitate was slowly added to 400 mL of cold n-hexane and stirred until it precipitated. The precipitate was filtered, washed with cold n-hexane (3 × 50 mL), and dried under vacuum at 60 °C for 12 h to obtain the corrosion inhibitor. The reaction equation is shown below:

[0045]

[0046] Its 1H NMR spectrum is as follows Figure 1 As shown, its 1H NMR spectrum data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 9.60 (m, 2H), 8.98 (ddd, J = 4.1, 2.6, 1.4 Hz, 2H), 8.70 (tt, J = 3.2,1.5 Hz, 2H), 8.43 (ddt, J = 8.8, 3.0, 2.5 Hz, 2H), 8.27 (dddd, J = 8.1, 4.2,3.1, 1.2 Hz, 2H), 8.08 (dddd, J = 8.8, 7.8, 1.2 Hz, 2H), 7.95 (s, 4H), 7.79 –7.72 (m, 2H), 7.34 (q, J = 0.6 Hz, 2H), 5.93 (t, J = 2.9 Hz, 4H), 3.59 (s, 9H), 3.47 (td, J = 6.9, 1.3 Hz, 4H), 3.01 – 2.93 (m, 1H), 2.80 – 2.68 (m, 2H), 2.58 – 2.43 (m, 2H), 2.31 (s, 3H), 1.96 (td, J = 10.0, 2.8 Hz, 4H), 1.77– 1.53 (m, 10H), 1.49 – 1.35 (m, 8H), 1.22 (d, J = 7.1 Hz, 3H), 0.79 (t, J = 9.1 Hz, 2H); its high-resolution mass spectrum is shown below. Figure 2 As shown, HRMS (m / z): 519.2078 [M-Cl] 2+ .

[0047] Example 2: Preparation of corrosion inhibitor:

[0048] S1: Under nitrogen protection, 200 mL of dichloromethane and 0.1 mol of 2,6-bis(chloromethyl)-4-methylphenol were added to the reaction flask and stirred to dissolve. Then, 1.5 g of catalyst DMAP, 50 mg of polymerization inhibitor hydroquinone, and 0.12 mol of triethylamine were added and stirred. Under ice bath conditions, 0.108 mol of methacryloyl chloride was slowly added dropwise over 20 min. After the addition was complete, the temperature was raised to reflux and reacted for 3 h. The mixture was then cooled to room temperature and the reaction solution was slowly poured into 300 mL of ice water. The mixture was separated, and the aqueous phase was extracted three times with dichloromethane (100 mL each time). The organic phases were combined and washed successively with 100 mL of saturated sodium bicarbonate solution, 100 mL of deionized water, and 100 mL of saturated sodium chloride solution. The mixture was dried with 40 g of anhydrous sodium sulfate, filtered, and rotary evaporated at 35 °C for 1 h. The mixture was then vacuum dried at 50 °C for 12 h to obtain intermediate 1.

[0049] S2: Under nitrogen protection, add 250 ml of anhydrous tetrahydrofuran, 0.1 mol of intermediate 1, 0.103 mol of 3-mercaptopropyltrimethoxysilane, and 0.5 g of photoinitiator 184 to the reaction flask, stir and mix well, and at room temperature, at an intensity of 8.4 mW / cm². 2 After irradiation under a 365nm UV LED lamp for 3.5h, the mixture was rotary evaporated at 40℃ for 1h, then slowly added to 200mL of cold n-hexane, stirred, and the precipitate was precipitated. The precipitate was filtered, washed three times with cold n-hexane (50mL each time), and dried under vacuum at 40℃ for 12h to obtain intermediate 2.

[0050] S3: Under nitrogen protection, 100 ml of anhydrous tetrahydrofuran, 0.1 mol of 3-quinoline carbaldehyde, and 10 g of 4A molecular sieve (sodium-A type molecular sieve) were added to the reaction flask. The mixture was stirred and mixed. 200 ml of methanol solution containing 0.108 mol of 6-aminohexane phosphoric acid and 0.11 mol of triethylamine was slowly added dropwise over 20 min. After the addition was complete, the mixture was heated to reflux for 5.5 h, cooled to room temperature, filtered, and the filtrate was distilled under reduced pressure at 40 °C for 1 h. Then, 300 ml of cold n-hexane was added, and the mixture was stirred to precipitate the precipitate. The precipitate was filtered, washed three times with petroleum ether (50 ml each time), and dried under vacuum at 40 °C for 12 h to obtain intermediate 3.

[0051] S4: Under nitrogen protection, add 800 mL of anhydrous acetonitrile, 0.1 mol of intermediate 2, and 0.208 mol of intermediate 3 to the reaction flask, stir and mix well, heat to reflux for 11 h, cool to room temperature, rotary evaporate at 50 °C for 1 h, slowly add to 400 mL of cold n-hexane, stir to precipitate, filter, wash with cold n-hexane (3 × 50 mL), and vacuum dry at 60 °C for 12 h to obtain the corrosion inhibitor.

[0052] Example 3: Preparation of corrosion inhibitor:

[0053] S1: Under nitrogen protection, 200 mL of dichloromethane and 0.1 mol of 2,6-bis(chloromethyl)-4-methylphenol were added to the reaction flask and stirred to dissolve. Then, 1.5 g of catalyst DMAP, 50 mg of polymerization inhibitor hydroquinone, and 0.12 mol of triethylamine were added and stirred. Under ice bath conditions, 0.11 mol of methacryloyl chloride was slowly added dropwise over 20 min. After the addition was complete, the temperature was raised to reflux and reacted for 4 h. The mixture was then cooled to room temperature and the reaction solution was slowly poured into 300 mL of ice water. The mixture was separated, and the aqueous phase was extracted three times with dichloromethane (100 mL each time). The organic phases were combined and washed successively with 100 mL of saturated sodium bicarbonate solution, 100 mL of deionized water, and 100 mL of saturated sodium chloride solution. The mixture was dried with 40 g of anhydrous sodium sulfate, filtered, and rotary evaporated at 35 °C for 1 h. The mixture was then vacuum dried at 50 °C for 12 h to obtain intermediate 1.

[0054] S2: Under nitrogen protection, add 250 ml of anhydrous tetrahydrofuran, 0.1 mol of intermediate 1, 0.105 mol of 3-mercaptopropyltrimethoxysilane, and 0.5 g of photoinitiator 184 to the reaction flask, stir and mix well, and at room temperature, at an intensity of 8.4 mW / cm². 2 After irradiation under a 365nm ultraviolet LED lamp for 3 hours, the mixture was rotary evaporated at 40℃ for 1 hour, then slowly added to 200mL of cold n-hexane, stirred, and precipitated. The precipitate was filtered, washed three times with cold n-hexane (50mL each time), and dried under vacuum at 40℃ for 12 hours to obtain intermediate 2.

[0055] S3: Under nitrogen protection, 100 ml of anhydrous tetrahydrofuran, 0.1 mol of 3-quinoline carbaldehyde, and 10 g of 4A molecular sieve (sodium-A type molecular sieve) were added to the reaction flask. The mixture was stirred and mixed. 200 ml of methanol solution containing 0.11 mol of 6-aminohexane phosphoric acid and 0.11 mol of triethylamine was slowly added dropwise over 20 min. After the addition was complete, the mixture was heated to reflux and reacted for 5 h. The mixture was then cooled to room temperature, filtered, and the filtrate was distilled under reduced pressure at 40 °C for 1 h. Then, 300 ml of cold n-hexane was added, and the mixture was stirred to precipitate the precipitate. The precipitate was filtered, washed three times with petroleum ether (50 ml each time), and dried under vacuum at 40 °C for 12 h to obtain intermediate 3.

[0056] S4: Under nitrogen protection, add 800 mL of anhydrous acetonitrile, 0.1 mol of intermediate 2, and 0.21 mol of intermediate 3 to the reaction flask, stir and mix well, heat to reflux for 10 h, cool to room temperature, rotary evaporate at 50 °C for 1 h, slowly add to 400 mL of cold n-hexane, stir to precipitate, filter, wash with cold n-hexane (3 × 50 mL), and vacuum dry at 60 °C for 12 h to obtain the corrosion inhibitor.

[0057] Example 4: Preparation of water-reducing agent:

[0058] A1: Under nitrogen protection, 800 ml of DMF (N,N-dimethylformamide), 0.1 mol of N,N,N,N,-tetracyclooxypropyl-4,4-diaminodiphenylmethane, and 0.402 mol of 4-aminonaphthalene-1,6-disulfonic acid were added to a reaction flask. The mixture was stirred and mixed thoroughly. 0.81 mol of triethylamine was slowly added dropwise over 20 min. After the addition was complete, the temperature was raised to 80 °C and the reaction was allowed to proceed for 6 h. The mixture was then cooled to room temperature and distilled under reduced pressure at 70 °C for 2 h. The precipitate was dissolved in 300 ml of deionized water, filtered, and then 500 ml of acetone was added. The precipitate was stirred and collected by suction filtration. The precipitate was washed three times with acetone (100 ml each time) and dried under vacuum at 60 °C for 12 h to obtain the four-armed compound. The reaction equation is shown below:

[0059]

[0060] Its 1H NMR data are as follows: 1 H NMR (400 MHz, DMSO- d 6 ) δ 8.68 (dt, J = 2.1, 0.5Hz, 4H), 8.34 (dt, J = 8.9, 1.5 Hz, 4H), 8.06 (dd, J = 8.9, 2.2 Hz, 4H), 7.89 (dd, J = 9.3, 2.5 Hz, 4H), 7.46 (s, 4H), 7.30 (t, J = 6.7 Hz, 4H), 7.14 (dd,J = 9.3, 3.5 Hz, 4H), 7.05 – 7.00 (m, 4H), 6.78 – 6.73 (m, 4H), 5.57 (s, 4H), 4.76 (d, J = 5.5 Hz, 4H), 4.38 (p, J = 3.8 Hz, 2H), 4.13 – 4.02 (m, 4H), 3.55 – 3.43 (m, 8H), 3.28 – 3.17 (m, 8H); HRMS (m / z): 1635.1696[M+H] + .

[0061] A2: Under nitrogen protection, 1000 mL of xylene, 0.1 mol of the four-arm compound, 0.406 mol of methyl linoleate, and 0.005 mol of dibutyltin oxide were added to a reaction flask. The mixture was stirred and refluxed for 6 h (methanol was removed using a Dean-Stark water separator during the reaction). After cooling to room temperature, the mixture was washed three times with saturated brine (100 mL each time), dried over 80 g of anhydrous sodium sulfate, filtered, and the filtrate was distilled under reduced pressure at 70 °C for 2 h. The filtrate was purified by silica gel column chromatography using a mixed solution of petroleum ether and ethyl acetate (petroleum ether / ethyl acetate volume ratio of 10:1 → 20:1 gradient elution). The mixture was distilled under reduced pressure at 50 °C for 1 h and dried under vacuum at 60 °C for 12 h to obtain the long-chain olefin-modified four-arm compound. The reaction equation is shown below:

[0062]

[0063] Its 1H NMR data are as follows: 1 H NMR (400 MHz, DMSO- d 6 ) δ 8.68 (dt, J = 5.2, 1.8Hz, 4H), 8.34 (dt, J = 8.9, 1.5 Hz, 4H), 8.06 (dd, J = 8.9, 2.1 Hz, 4H), 7.89 (dd, J = 9.3, 2.5 Hz, 4H), 7.52 – 7.44 (m, 8H), 7.15 (dd, J = 9.3, 2.8 Hz,4H), 7.06 – 7.00 (m, 4H), 6.78 – 6.72 (m, 4H), 5.57 (s, 4H), 5.53 – 5.37 (m,16H), 5.22 (p, J = 4.7 Hz, 4H), 4.38 (p, J = 3.9 Hz, 2H), 3.89 – 3.40 (m,16H), 2.41 – 2.23 (m, 16H), 2.08 – 1.96 (m, 16H), 1.53 – 1.21 (m, 64H), 0.92– 0.84 (m, 12H); HRMS (m / z): 2685.0914[M+H] + .

[0064] A3: Under nitrogen protection, add 1200 ml of tetrahydrofuran, 0.1 mol of long-chain olefin-modified four-arm compound, 0.805 mol of 7-mercaptoheptanoic acid, and 2.5 g of photoinitiator 184 to the reaction flask, stir and mix well, and at room temperature, at an intensity of 8.4 mW / cm². 2After irradiation under a 365nm UV LED lamp for 4 hours, the mixture was rotary evaporated at 40℃ for 1 hour. The solution was then slowly added to 600mL of cold diethyl ether, stirred, and a precipitate formed. The precipitate was filtered, washed three times with 50mL of cold diethyl ether each time, and then vacuum dried at 40℃ for 12 hours to obtain the water-reducing agent. The reaction equation is shown below:

[0065]

[0066] Its 1H NMR spectrum is as follows Figure 3 As shown, its 1H NMR spectrum data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 10.33 (s, 8H), 8.70 (dt, J = 2.2, 1.2 Hz, 4H), 8.34 (dt, J = 8.9, 3.6Hz, 4H), 8.01 (dd, J = 8.9, 2.1 Hz, 4H), 7.93 (dd, J = 9.3, 3.7 Hz, 4H), 7.61(s, 4H), 7.14 (dd, J = 9.3, 4.2 Hz, 4H), 7.07 – 7.02 (m, 4H), 6.87 (t, J =6.4 Hz, 4H), 6.69 – 6.63 (m, 4H), 5.49 (s, 4H), 5.29 – 5.15 (m, 4H), 4.09 (p, J = 4.8 Hz, 2H), 3.94 – 3.47 (m, 16H), 2.89 (p, J = 5.5 Hz, 8H), 2.50 (ddt, J = 51.8, 13.4, 6.3 Hz, 16H), 2.36 – 2.24 (m, 24H), 1.77 – 1.18 (m, 168H), 0.97– 0.73 (m, 12H); its high-resolution mass spectrum is shown below. Figure 4 As shown, HRMS (m / z): 3982.6664 [M+H] + .

[0067] Example 5: Preparation of Eco-friendly Corrosion-resistant Cement:

[0068] (1) Raw material pretreatment: Clinker, slag, mineral powder and fly ash are crushed and passed through a 300-mesh sieve respectively;

[0069] (2) Weigh out: 600g clinker, 50g slag, 150g mineral powder, 150g fly ash, 50g gypsum, 30g silica fume, 20g corrosion inhibitor (prepared in Example 1), and 10g water-reducing agent (prepared in Example 4);

[0070] (3) Put the above raw materials into a mixer and dry mix at 300r / min for 5min to obtain a mixture; send the mixture into a cement mill for grinding, and control the temperature of the grinding process at 90℃ to obtain ecological corrosion-resistant cement.

[0071] Example 6: Preparation of Eco-friendly Corrosion-resistant Cement:

[0072] (1) Raw material pretreatment: Clinker, slag, mineral powder and fly ash are crushed and passed through a 300-mesh sieve;

[0073] (2) Weigh out: 650g clinker, 80g slag, 180g mineral powder, 180g fly ash, 55g gypsum, 35g silica fume, 25g corrosion inhibitor (prepared in Example 2), and 15g water-reducing agent (prepared in Example 4);

[0074] (3) Put the above raw materials into a mixer and dry mix at 300r / min for 5min to obtain a mixture; send the mixture into a cement mill for grinding, and control the temperature of the grinding process at 90℃ to obtain ecological corrosion-resistant cement.

[0075] Example 7: Preparation of Eco-friendly Corrosion-resistant Cement:

[0076] (1) Raw material pretreatment: Clinker, slag, mineral powder and fly ash are crushed and passed through a 300-mesh sieve;

[0077] (2) Weigh out: 700g clinker, 100g slag, 200g mineral powder, 200g fly ash, 60g gypsum, 40g silica fume, 30g corrosion inhibitor (prepared in Example 3), and 20g water-reducing agent (prepared in Example 4);

[0078] (3) Put the above raw materials into a mixer and dry mix at 300r / min for 5min to obtain a mixture; send the mixture into a cement mill for grinding, and control the temperature of the grinding process at 90℃ to obtain ecological corrosion-resistant cement.

[0079] Comparative Example 1

[0080] The eco-friendly corrosion-resistant cement is basically the same as that in Example 6, except that the corrosion inhibitor is replaced with an equal weight of corrosion inhibitor prepared by the following method:

[0081] The preparation method of the corrosion inhibitor is basically the same as that in Example 2, except that 2,6-bis(chloromethyl)-4-methylphenol in step S1 is replaced with an equimolar amount of 4-hydroxybenzyl chloride; and the amount of intermediate 3 fed in step S4 is 0.108 mol.

[0082] Comparative Example 2

[0083] The eco-friendly corrosion-resistant cement is basically the same as that in Example 6, except that the corrosion inhibitor is replaced with an equal weight of corrosion inhibitor prepared by the following method:

[0084] The preparation method of the corrosion inhibitor is basically the same as that in Example 2, except that 3-quinoline formaldehyde in step S3 is replaced with an equimolar amount of 6-quinoline formaldehyde.

[0085] Comparative Example 3

[0086] The eco-friendly corrosion-resistant cement is basically the same as that in Example 6, except that the corrosion inhibitor is replaced with an equal weight of corrosion inhibitor prepared by the following method:

[0087] The preparation method of the corrosion inhibitor is basically the same as that in Example 2, except that 6-aminohexane phosphate in step S3 is replaced with an equimolar amount of (2-aminoethyl) phosphonate diethyl ester.

[0088] Comparative Example 4

[0089] The eco-friendly corrosion-resistant cement is basically the same as that in Example 6, except that the corrosion inhibitor is replaced with an equal weight of corrosion inhibitor prepared by the following method:

[0090] The preparation method of the corrosion inhibitor is basically the same as that in Example 2, except that 6-aminohexanephosphoric acid in step S3 is replaced with an equimolar amount of aminomethylphosphonic acid.

[0091] Comparative Example 5

[0092] The eco-friendly corrosion-resistant cement is basically the same as in Example 6, except that the water-reducing agent is replaced with an equal weight of water-reducing agent prepared by the following method:

[0093] The preparation method of the water-reducing agent is basically the same as that in Example 4, except that the 4-aminonaphthalene-1,6-disulfonic acid in step A1 is replaced with an equimolar amount of 4-naphthylamine-1-sulfonic acid.

[0094] Comparative Example 6

[0095] The eco-friendly corrosion-resistant cement is basically the same as in Example 6, except that the water-reducing agent is replaced with an equal weight of water-reducing agent prepared by the following method:

[0096] The preparation method of the water-reducing agent is basically the same as that in Example 4, except that the 4-aminonaphthalene-1,6-disulfonic acid in step A1 is replaced with an equimolar amount of 2-amino-1,4-benzenedisulfonic acid.

[0097] Comparative Example 7

[0098] The eco-friendly corrosion-resistant cement is basically the same as in Example 6, except that the water-reducing agent is replaced with an equal weight of water-reducing agent prepared by the following method:

[0099] The preparation method of the water-reducing agent is basically the same as that in Example 4, except that N,N,N,N-tetracyclooxypropyl-4,4-diaminodiphenylmethane in step A1 is replaced with an equimolar amount of N,N,N',N'-tetra(epoxyethylenemethyl)-1,3-phenylenediamine.

[0100] Comparative Example 8

[0101] The eco-friendly corrosion-resistant cement is basically the same as in Example 6, except that the water-reducing agent is replaced with an equal weight of water-reducing agent prepared by the following method:

[0102] The preparation method of the water-reducing agent is basically the same as that in Example 4, except that the methyl linoleate in step A2 is replaced with an equimolar amount of methyl oleate, and the amount of 7-mercaptoheptanoic acid added in step A3 is 0.405 mol.

[0103] Comparative Example 9

[0104] The eco-friendly corrosion-resistant cement is basically the same as in Example 6, except that the water-reducing agent is replaced with an equal weight of water-reducing agent prepared by the following method:

[0105] The preparation method of the water-reducing agent is basically the same as that in Example 4, except that 7-mercaptoheptanoic acid in step A3 is replaced with an equimolar amount of 3-mercaptopropionic acid.

[0106] The main components of the clinker used in the embodiments and comparative examples of this application include: 54.52wt% CaO, 26.35wt% SiO2, 8.71wt% Al2O3, 3.67wt% Fe2O3, and 2.86wt% MgO; the main components of the slag include: 7.67wt% MgO, 16.72wt% Al2O3, 24.88wt% SiO2, 27.43wt% CaO, 21.74wt% TiO2, and 0.34wt% Fe2O3; and the main components of the mineral powder include: 33.31wt% SiO2, 10.76wt% Al2O3, and 8.58wt% Fe2O3. O3, 35.60wt%CaO, 5.45wt%MgO; fly ash main components include: 54.91wt%SiO2, 26.43wt%Al2O3, 11.25wt%Fe2O3, 5.84wt%CaO; silica fume main components include: 94.61wt%SiO2, 0.06wt%chloride, 0.86wt%Fe, 0.24wt%Na2O, 1.60wt%K2O, 0.02wt%Mn, 0.43wt%Al2O3; the gypsum type is MH-16 high-purity ultrafine extra-white hemihydrate gypsum powder, produced by Jingmen Leixin Gypsum Products Co., Ltd.

[0107] Application example: The cement prepared in the examples and comparative examples was applied to mortar, and the mortar mix proportions are shown in Table 1.

[0108] Table 1 Mortar Mix Proportion Table (kg / m³) 3 )

[0109]

[0110] The sand conforms to Chinese ISO standards, with a particle size of 0.5-1.0mm, and is produced by Xiamen Aisiou Standard Sand Co., Ltd.

[0111] Sample preparation: Pour the mortar prepared above into a mold and vibrate to form; after 24 hours, demold and cure in water at (23±2)℃ for 6 days, then place at (23±2)℃ and 50% relative humidity for 28 days. Before the test, smooth the molded surface of the cement mortar specimen with 200# sandpaper or grinding stone.

[0112] Compressive strength / flexural strength test: The compressive strength and flexural strength are tested in accordance with GBT17671-2021 "Test Method for Strength of Cement Mortar (ISO Method)". A 40mm×40mm×160mm prism mold is selected for sample preparation.

[0113] Chloride ion penetration resistance test: The chloride ion diffusion coefficient was tested according to the test method of GB / T 42272-2022 "Test Method for Chloride Ion Diffusion Coefficient of Cement Mortar". A 100mm×100mm×50mm mold was selected for sample preparation.

[0114] Cement paste fluidity test: The fluidity of cement paste was tested according to the test method in Part 15 of GB / T 8077-2023.

[0115] Table 1 Test Data of Eco-friendly Corrosion-resistant Cement

[0116]

[0117] As can be seen from Table 1, the eco-friendly corrosion-resistant cement prepared in Examples 5-7 of this application has good compressive strength, flexural strength, fluidity, and corrosion resistance.

[0118] The corrosion inhibitor prepared in this application uses an aromatic heterocyclic core as its backbone. One end is connected to a trimethoxysilane-containing group via ester and thioether bonds, while the other two ends are linked to a quinoline ring via a quaternization reaction, forming a quinoline quaternary ammonium salt cation center. This structure significantly improves the overall performance of cement-based materials through the synergistic effect of different functional groups. First, the quinoline quaternary ammonium salt cation preferentially adsorbs onto the surface of the reinforcing steel through electrostatic interactions, forming a hydrophobic barrier that effectively repels chloride ions. The terminal phosphonic acid group chelates with iron ions to form a dense organophosphonate iron protective film, and this chemical passivation significantly delays the corrosion of the reinforcing steel. Second, the trimethoxysilane group hydrolyzes into silanol groups in an aqueous alkaline environment, which chemically bonds with cement hydration products. This not only firmly anchors the corrosion inhibitor in the cement matrix but also participates in secondary hydration reactions, refining the pore structure and blocking the penetration of corrosive media. Finally, the flexible alkyl chains connecting the active centers endow the molecules with appropriate conformational freedom. The synergistic effect of multiple functional groups not only effectively reduces chloride ion intrusion and corrosion rate, but also optimizes the microstructure of the cement matrix, reduces defects and microcracks, thereby achieving a synergistic improvement in mechanical properties and corrosion resistance.

[0119] In Comparative Example 2, the main reason for the decrease in corrosion inhibitor performance after replacing 3-quinoline carboxaldehyde in step S3 with an equimolar amount of 6-quinoline carboxaldehyde is the change in molecular electronic effects and spatial configuration caused by the change in the substitution position of the aldehyde group. The aldehyde group of 3-quinoline carboxaldehyde is located near the heterocyclic nitrogen, which can form effective conjugation with the cyclic nitrogen, concentrating the molecular electron cloud and making it easier to bind with Fe on the steel reinforcement surface. 2+ / Fe 3+ Coordination adsorption occurs, forming a dense and continuous protective film; however, the aldehyde group of 6-quinoline carbaldehyde is located at the end of the benzene ring, weakening the conjugation effect. This increases steric hindrance when the molecule adsorbs on the metal surface, leading to a looser film arrangement and reduced coverage. Furthermore, the increased interfunctional group spacing weakens the multidentate complexation ability, affecting the stability of the corrosion inhibitor in the cement pore solution and its interaction with Ca. 2+ Fe 3+ The reduced complexing ability weakens the regulatory effect on the densification of cement hydration products, resulting in a decrease in the effectiveness of corrosion inhibitors in both corrosion resistance and mechanical property improvement.

[0120] The water-reducing agent prepared in this application is composed of a rigid hydrophobic backbone (aromatic ring) and flexible hydrophilic side chains (carboxyl groups and sulfonic acid groups). The carboxyl groups and sulfonic acid groups can react with the Ca released during the initial stage of cement hydration. 2+Complexation or electrostatic adsorption occurs, causing the water-reducing agent molecules to firmly adsorb onto the surface of cement particles, significantly enhancing the electrostatic repulsion between particles, thereby effectively disrupting the flocculation structure and improving the fluidity of the slurry. The aromatic ring structure improves the rigidity and adsorption stability of the molecules, which is beneficial to the water-reducing agent's tolerance in high-alkali and high-ionic-strength cement systems. Through the synergistic effect of "complexation-electrostatic repulsion-steric hindrance," the above functional groups improve the dispersion efficiency and water reduction rate of the cement system, optimize the cement hydration process, and make the hydration products more uniformly distributed, thereby improving mechanical properties, density, and durability.

[0121] In Comparative Example 6, after replacing 4-aminonaphthalene-1,6-disulfonic acid in step A1 with 2-amino-1,4-benzenedisulfonic acid, the main reasons for the performance degradation are as follows: 4-aminonaphthalene-1,6-disulfonic acid has a rigid naphthalene ring skeleton and a wide distribution of sulfonic acid groups, which can provide greater spatial coverage and electrostatic repulsion, enabling the water-reducing agent molecules to form a uniform adsorption layer on the surface of cement particles, effectively destroying the flocculation structure and stabilizing the dispersion of the slurry; while 2-amino-1,4-benzenedisulfonic acid has a smaller benzene ring structure, with sulfonic acid groups close to the ring center, resulting in less molecular rigidity and coverage area, insufficient steric hindrance, leading to insufficient adsorption on the particle surface and weakened dispersion. Simultaneously, the electronic effect on Ca... 2+ The complexing ability of the water-reducing agent decreases, and the adsorption efficiency and flow retention performance of the water-reducing agent in the cement paste decrease, thereby reducing the fluidity of the cement paste.

[0122] 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. An eco-friendly corrosion-resistant cement, characterized in that, The raw materials include the following parts by weight: 60-70 parts clinker, 5-10 parts slag, 15-20 parts mineral powder, 15-20 parts fly ash, 5-6 parts gypsum, 3-4 parts silica fume, 2-3 parts corrosion inhibitor, and 1-2 parts water-reducing agent. The corrosion inhibitor is prepared by the following method: S1: 2,6-Bis(chloromethyl)-4-methylphenol reacts with methacrylyl chloride to form intermediate 1. S2: Intermediate 1 reacts with 3-mercaptopropyltrimethoxysilane to generate intermediate 2. S3: 3-Quinoline carbaldehyde reacts with 6-aminohexane phosphoric acid to form intermediate 3. S4: Intermediate 2 reacts with intermediate 3 to form a corrosion inhibitor; In step S1, the molar ratio of 2,6-bis(chloromethyl)-4-methylphenol to methacrylamide chloride is 1:(1.05-1.1). In step S2, the molar ratio of intermediate 1 to 3-mercaptopropyltrimethoxysilane is 1:(1.02-1.05); In step S3, the molar ratio of 3-quinoline formaldehyde to 6-aminohexane phosphoric acid is 1:(1.05-1.1). In step S4, the molar ratio of intermediate 2 to intermediate 3 is 1:(2.05-2.1); The water-reducing agent is prepared by the following method: A1: 4-Aminonaphthalene-1,6-disulfonic acid reacts with N,N,N,N,-tetracyclooxypropyl-4,4-diaminodiphenylmethane to form a four-armed compound. A2: The four-armed compound reacts with methyl linoleate to generate a long-chain olefin-modified four-armed compound. A3: A long-chain olefin-modified four-arm compound reacts with 7-mercaptoheptanoic acid to generate a water-reducing agent; In step A1, the molar ratio of 4-aminonaphthalene-1,6-disulfonic acid to N,N,N,N,-tetracyclooxypropyl-4,4-diaminodiphenylmethane is 4.02:

1. In step A2, the molar ratio of the four-armed compound to methyl linoleate is 1:4.06; In step A3, the molar ratio of the long-chain olefin-modified tetra-arm compound to 7-mercaptoheptanoic acid is 1:8.

05.

2. A method for preparing the eco-friendly corrosion-resistant cement according to claim 1, characterized in that, Includes the following steps: (1) Raw material pretreatment: Clinker, slag, mineral powder and fly ash are crushed and sieved; (2) Weigh out the following by weight: 60-70 parts clinker, 5-10 parts slag, 15-20 parts mineral powder, 15-20 parts fly ash, 5-6 parts gypsum, 3-4 parts silica fume, 2-3 parts corrosion inhibitor, and 1-2 parts water-reducing agent. (3) Put the above raw materials into a mixer and dry mix them to obtain a mixture; send the mixture into a cement mill for grinding to obtain ecological corrosion-resistant cement.

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