Durable concrete and preparation method thereof

Abstract

The present invention relates to the technical field of concrete and discloses a durable concrete and a preparation method thereof. The method comprises adding cement, crushed stone, fly ash, a polycarboxylate water-reducing agent, a quaternized triazine-based polyurethane, a modified cyclodextrin, and water into a mixer, stirring the mixture uniformly, and stirring to obtain the durable concrete. The quaternary ammonium salt groups in the quaternized triazine-based polyurethane can effectively reduce the adsorption of the water-reducing agent by clay, thereby reducing the amount of admixture and improving the performance and durability of the concrete. The triazine groups therein have certain chemical stability and corrosion resistance, which helps to reduce chloride salt corrosion of the concrete in harsh environments, thereby extending the service life of the concrete.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete, in particular to durable concrete and a preparation method thereof. Background Art

[0002] Concrete is a general term for engineering composite materials composed of aggregates bonded together by cementitious materials. Cement concrete is characterized by readily available raw materials, convenient construction, and low cost. During long-term use, pavement concrete is subject to chloride ion penetration and erosion, thus affecting its durability. For example, patent CN118878269A discloses a durable concrete and a method for preparing it. This invention uses a lithium carbonate-modified organosilicon emulsion in combination with other components to achieve high durability (impermeability and chloride ion resistance). However, its composition is relatively simple, and its durability needs further improvement. Summary of the Invention

[0003] (1) Technical problems solved

[0004] In view of the deficiencies of the prior art, the present invention provides a durable concrete and a preparation method thereof, which has good durability and resistance to chloride ion corrosion.

[0005] (2) Technical solution

[0006] To achieve the above object, the present invention provides the following technical solution: a durable concrete comprising the following components by weight: 200-300 parts by weight of cement, 350-400 parts by weight of crushed stone, 8-16 parts by weight of fly ash, 0.2-0.4 parts by weight of a polycarboxylate water reducer, 4-8 parts by weight of a quaternized triazine-based polyurethane, 3-6 parts by weight of a modified cyclodextrin, and 150-300 parts by weight of water;

[0007] The preparation method of the quaternized triazine-based polyurethane is:

[0008] Step 1: Add 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heat to 30-45°C and react for 6-8 hours, cool to room temperature, add sodium borohydride, react for 2-4 hours, and after the reaction, add dilute hydrochloric acid to adjust the pH of the solution to 3.5-4 to precipitate. After filtering, the product is recrystallized with ethanol to obtain triazinyl lysine;

[0009] Step 2: Add triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stir and mix, then add p-toluenesulfonic acid catalyst, react at 90-110°C for 4-7h, wash and dry to obtain intermediate 1;

[0010] Step 3: Add the intermediate 1,3-chloro-1-propanol to acetone solvent, stir evenly, react at 65-85°C for 2-6 hours, and then perform rotary distillation to obtain a quaternized triazine chain extender;

[0011] Step 4: Add toluene diisocyanate and polyether polyol to a reactor, then add dibutyltin dilaurate catalyst, and carry out prepolymerization under a nitrogen atmosphere. The prepolymerization temperature is 75-95°C and the prepolymerization time is 2-3h. Then add a quaternized triazine chain extender and stir to carry out a chain extension reaction. The reaction is carried out at 40-65°C for 20-25 minutes. After the reaction is completed, it is naturally cooled to obtain a quaternized triazine polyurethane.

[0012] Preferably, in step 1, the mass ratio of 2,4,6-tris(4-formaldehydephenyl)-1,3,5-triazine, L-lysine, and sodium borohydride is 1:1.8-2.3:0.2-0.5.

[0013] Preferably, in step 2, the mass ratio of triazine lysine, 3-dimethylamino-1-propanol, and p-toluenesulfonic acid catalyst is 0.4-0.6:1:0.01-0.03.

[0014] Preferably, the mass ratio of the intermediate 1 and 3-chloro-1-propanol in step 3 is 1:1.2-1.5.

[0015] Preferably, in the step 4, the mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst, and quaternized triazine chain extender is 1:1.1-1.3:0.01-0.03:0.4-0.6.

[0016] Preferably, the preparation method of the modified cyclodextrin is:

[0017] S1. 15-20 parts by weight of thionyl chloride and 12-14 parts by weight of triazine-lysine were added to the reactor, and the reaction was carried out at 65-85 ° C for 4-8h. After completion, the mixture was cooled to room temperature, concentrated under reduced pressure, washed with petroleum ether, and dried to obtain triazine-lysine chloride;

[0018] S2. Add 5-8 parts by weight of triazine lysine chloride and 12-18 parts by weight of β-cyclodextrin to N,N-dimethylformamide solvent, stir and disperse, continue to add 0.1-0.2 parts by weight of triethylamine catalyst, react at 70-90°C for 6-10h, and then distill under reduced pressure and wash to obtain modified cyclodextrin.

[0019] Preferably, the preparation method of the durable concrete is: adding cement, crushed stone, fly ash, polycarboxylate water reducer, quaternized triazine-based polyurethane, modified cyclodextrin, and water into a mixer, stirring evenly for 50-100 seconds to obtain durable concrete.

[0020] (3) Beneficial technical effects

[0021] The method comprises adding cement, crushed stone, fly ash, polycarboxylate water reducer, quaternized triazine-based polyurethane, modified cyclodextrin and water into a mixer, stirring the mixture evenly and obtaining durable concrete.

[0022] The quaternary ammonium salt groups in the quaternized triazine-based polyurethane can effectively reduce the adsorption of clay on water reducers, thereby reducing the amount of admixtures added and improving the performance and durability of concrete. The triazine groups have certain chemical stability and corrosion resistance, which helps to reduce chloride attack on concrete in harsh environments, thereby extending the service life of concrete. The polyurethane itself can also improve the durability of concrete. The acyl chloride groups in the acyl chloride triazine lysine react with the hydroxyl groups in β-cyclodextrin to obtain modified cyclodextrin, while increasing the degree of substitution of the cyclodextrin. The cyclodextrin can increase the density of concrete, thereby further improving the durability of concrete. DETAILED DESCRIPTION

[0023] Example 1

[0024] (1) Add 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heat to 30°C and react for 6 hours, cool to room temperature, add sodium borohydride, wherein the mass ratio of 2,4,6-tris(4-formylphenyl)-1,3,5-triazine, L-lysine and sodium borohydride is 1:1.8:0.2, react for 2 hours, add dilute hydrochloric acid after the reaction to adjust the pH of the solution to 3.5, precipitate, filter the product and recrystallize it with ethanol to obtain triazine lysine;

[0025] (2) Add triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stir and mix, and continue to add p-toluenesulfonic acid catalyst, wherein the mass ratio of triazine lysine, 3-dimethylamino-1-propanol, and p-toluenesulfonic acid catalyst is 0.4:1:0.01, react at 90°C for 4 hours, wash after completion, and dry to obtain intermediate 1;

[0026] (3) Add the intermediate 1, 3-chloro-1-propanol to acetone solvent, wherein the mass ratio of the intermediate 1, 3-chloro-1-propanol is 1:1.2, stir evenly, react at 65 ° C for 2 hours, and after the reaction, rotary distill to obtain a quaternized triazine chain extender;

[0027] (4) Toluene diisocyanate and polyether polyol were added to a reactor, and then dibutyltin dilaurate catalyst was added. Prepolymerization was carried out under a nitrogen atmosphere at a temperature of 75°C for 2 hours. A quaternized triazine chain extender was then added, wherein the mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst, and quaternized triazine chain extender was 1:1.1:0.01:0.4. The chain extension reaction was stirred and reacted at 40°C for 20 minutes. After the reaction was completed, the mixture was naturally cooled to obtain a quaternized triazine polyurethane.

[0028] (5) Add 15 parts by weight of thionyl chloride and 12 parts by weight of triazine lysine to the reactor, react at 65°C for 4 hours, cool to room temperature, concentrate under reduced pressure, wash with petroleum ether, and dry to obtain triazine lysine chloride;

[0029] (6) Add 5 parts by weight of triazine lysine chloride and 12 parts by weight of β-cyclodextrin to N,N-dimethylformamide solvent, stir and disperse, continue to add 0.1 parts by weight of triethylamine catalyst, react at 70°C for 6 hours, and then distill under reduced pressure and wash to obtain modified cyclodextrin;

[0030] (7) 200 parts by weight of cement, 350 parts by weight of crushed stone, 8 parts by weight of fly ash, 0.2 parts by weight of polycarboxylic acid water reducer, 4 parts by weight of quaternized triazine-based polyurethane, 3 parts by weight of modified cyclodextrin, and 150 parts by weight of water were added into a mixer and stirred evenly for 50 seconds to obtain durable concrete.

[0031] Example 2

[0032] (1) Add 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heat to 45°C and react for 8 hours, cool to room temperature, add sodium borohydride, wherein the mass ratio of 2,4,6-tris(4-formylphenyl)-1,3,5-triazine, L-lysine and sodium borohydride is 1:2.3:0.5, react for 4 hours, add dilute hydrochloric acid after the reaction to adjust the pH of the solution to 4, precipitate, filter the product and recrystallize it with ethanol to obtain triazine lysine;

[0033] (2) Add triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stir and mix, and continue to add p-toluenesulfonic acid catalyst, wherein the mass ratio of triazine lysine, 3-dimethylamino-1-propanol and p-toluenesulfonic acid catalyst is 0.6:1:0.03, react at 110°C for 7 hours, wash and dry after completion to obtain intermediate 1;

[0034] (3) adding the intermediate 1, 3-chloro-1-propanol to an acetone solvent in a mass ratio of 1:1.5, stirring evenly, reacting at 85°C for 6 hours, and then rotary distilling to obtain a quaternized triazine chain extender;

[0035] (4) Toluene diisocyanate and polyether polyol were added to a reactor, and then dibutyltin dilaurate catalyst was added. Prepolymerization was carried out under a nitrogen atmosphere. The prepolymerization temperature was 95°C and the prepolymerization time was 3 hours. Then, a quaternized triazine chain extender was added. The mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst and quaternized triazine chain extender was 1:1.3:0.03:0.6. The chain extension reaction was stirred and reacted at 65°C for 25 minutes. After the reaction was completed, the mixture was naturally cooled to obtain a quaternized triazine polyurethane.

[0036] (5) Add 20 parts by weight of thionyl chloride and 14 parts by weight of triazine lysine to a reactor, react at 85°C for 8 hours, cool to room temperature, concentrate under reduced pressure, wash with petroleum ether, and dry to obtain triazine lysine chloride;

[0037] (6) Add 8 parts by weight of triazine lysine chloride and 18 parts by weight of β-cyclodextrin to N,N-dimethylformamide solvent, stir and disperse, continue to add 0.2 parts by weight of triethylamine catalyst, react at 90°C for 10 hours, and then distill under reduced pressure and wash to obtain modified cyclodextrin;

[0038] (7) 300 parts by weight of cement, 00 parts by weight of crushed stone, 16 parts by weight of fly ash, 0.4 parts by weight of polycarboxylic acid water reducer, 8 parts by weight of quaternized triazine-based polyurethane, 6 parts by weight of modified cyclodextrin, and 300 parts by weight of water were added into a mixer and stirred evenly for 100 seconds to obtain durable concrete.

[0039] Example 3

[0040] (1) Add 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heat to 35°C and react for 7 hours, cool to room temperature, add sodium borohydride, wherein the mass ratio of 2,4,6-tris(4-formylphenyl)-1,3,5-triazine, L-lysine and sodium borohydride is 1:3.1:0.3, react for 3 hours, add dilute hydrochloric acid after the reaction to adjust the pH of the solution to 3.8, precipitate, filter the product and recrystallize it with ethanol to obtain triazine lysine;

[0041] (2) Add triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stir and mix, and continue to add p-toluenesulfonic acid catalyst, wherein the mass ratio of triazine lysine, 3-dimethylamino-1-propanol, and p-toluenesulfonic acid catalyst is 0.5:1:0.02, react at 100°C for 6 hours, wash after completion, and dry to obtain intermediate 1;

[0042] (3) adding the intermediate 1, 3-chloro-1-propanol to an acetone solvent in a mass ratio of 1:1.3, stirring evenly, reacting at 75°C for 4 hours, and then rotary distilling to obtain a quaternized triazine chain extender;

[0043] (4) Toluene diisocyanate and polyether polyol were added to a reactor, and then dibutyltin dilaurate catalyst was added. Prepolymerization was carried out under a nitrogen atmosphere. The prepolymerization temperature was 85°C and the prepolymerization time was 2h. Then, a quaternized triazine chain extender was added. The mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst and quaternized triazine chain extender was 1:1.2:0.02:0.5. The chain extension reaction was stirred and reacted at 55°C for 22.5min. After the reaction was completed, the mixture was cooled naturally to obtain a quaternized triazine polyurethane.

[0044] (5) Add 18 parts by weight of thionyl chloride and 13 parts by weight of triazine lysine to a reactor, react at 75°C for 6 hours, cool to room temperature, concentrate under reduced pressure, wash with petroleum ether, and dry to obtain triazine lysine chloride;

[0045] (6) Add 6 parts by weight of triazine lysine chloride and 16 parts by weight of β-cyclodextrin to N,N-dimethylformamide solvent, stir and disperse, continue to add 0.15 parts by weight of triethylamine catalyst, react at 80°C for 8 hours, and then distill under reduced pressure and wash to obtain modified cyclodextrin;

[0046] (7) 250 parts by weight of cement, 380 parts by weight of crushed stone, 14 parts by weight of fly ash, 0.3 parts by weight of polycarboxylic acid water reducer, 6 parts by weight of quaternized triazine-based polyurethane, 5 parts by weight of modified cyclodextrin, and 280 parts by weight of water were added into a mixer and stirred evenly for 70 seconds to obtain durable concrete.

[0047] Example 4

[0048] (1) Add 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heat to 30°C and react for 6 hours, cool to room temperature, add sodium borohydride, wherein the mass ratio of 2,4,6-tris(4-formylphenyl)-1,3,5-triazine, L-lysine and sodium borohydride is 1:1.8:0.2, react for 2 hours, add dilute hydrochloric acid after the reaction to adjust the pH of the solution to 3.5, precipitate, filter the product and recrystallize it with ethanol to obtain triazine lysine;

[0049] (2) Add triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stir and mix, and continue to add p-toluenesulfonic acid catalyst, wherein the mass ratio of triazine lysine, 3-dimethylamino-1-propanol, and p-toluenesulfonic acid catalyst is 0.4:1:0.01, react at 90°C for 4 hours, wash after completion, and dry to obtain intermediate 1;

[0050] (3) adding the intermediate 1, 3-chloro-1-propanol to an acetone solvent in a mass ratio of 1:1.5, stirring evenly, reacting at 85°C for 6 hours, and then rotary distilling to obtain a quaternized triazine chain extender;

[0051] (4) Toluene diisocyanate and polyether polyol were added to a reactor, and then dibutyltin dilaurate catalyst was added. Prepolymerization was carried out under a nitrogen atmosphere. The prepolymerization temperature was 95°C and the prepolymerization time was 3 hours. Then, a quaternized triazine chain extender was added. The mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst and quaternized triazine chain extender was 1:1.3:0.03:0.6. The chain extension reaction was stirred and reacted at 65°C for 25 minutes. After the reaction was completed, the mixture was naturally cooled to obtain a quaternized triazine polyurethane.

[0052] (5) Add 18 parts by weight of thionyl chloride and 13 parts by weight of triazine lysine to a reactor, react at 75°C for 6 hours, cool to room temperature, concentrate under reduced pressure, wash with petroleum ether, and dry to obtain triazine lysine chloride;

[0053] (6) Add 6 parts by weight of triazine lysine chloride and 16 parts by weight of β-cyclodextrin to N,N-dimethylformamide solvent, stir and disperse, continue to add 0.15 parts by weight of triethylamine catalyst, react at 80°C for 8 hours, and then distill under reduced pressure and wash to obtain modified cyclodextrin;

[0054] (7) 250 parts by weight of cement, 380 parts by weight of crushed stone, 14 parts by weight of fly ash, 0.3 parts by weight of polycarboxylic acid water reducer, 6 parts by weight of quaternized triazine-based polyurethane, 5 parts by weight of modified cyclodextrin, and 280 parts by weight of water were added into a mixer and stirred evenly for 70 seconds to obtain durable concrete.

[0055] Comparative Example 1

[0056] Compared with Example 4, this comparative example differs in that no quaternized triazine-based polyurethane is added.

[0057] Comparative Example 2

[0058] Compared with Example 4, this comparative example differs in that no modified cyclodextrin is added.

[0059] Performance Testing

[0060] The obtained concrete was made into 150mm*150mm*150mm cubic specimens. The concrete specimens prepared in Examples 1-4 and Comparative Examples 1-2 were tested for compressive strength, flexural strength and chloride ion diffusion coefficient, wherein the compressive strength and flexural strength tests were conducted in accordance with GB / T 50081-2002 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete", and the chloride ion diffusion coefficient test was conducted in accordance with GB / T 50082-2009 "Standard for Test Methods of Long-term Performance and Durability of Ordinary Concrete". The specific test results are shown in Table 1. In addition, according to GB / T50476-2008 "Code for Durability Design of Concrete Structures", the chloride ion diffusion coefficient of Class E structures with a design life of 100 years should be less than .

[0061] Table 1: Performance tests.

[0062]

[0063] As can be seen from Table 1, Examples 1-4 of the present invention have better compressive strength and flexural strength than Comparative Examples 1-2, and also have better resistance to chloride ion corrosion.

[0064] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A durable concrete, characterized in that: The invention comprises the following components by weight: 200-300 parts by weight of cement, 350-400 parts by weight of crushed stone, 8-16 parts by weight of fly ash, 0.2-0.4 parts by weight of polycarboxylate water reducer, 4-8 parts by weight of quaternized triazine-based polyurethane, 3-6 parts by weight of modified cyclodextrin, and 150-300 parts by weight of water; The preparation method of the quaternized triazine-based polyurethane is: Step 1: Add 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heat to 30-45°C and react for 6-8 hours, cool to room temperature, add sodium borohydride, react for 2-4 hours, and after the reaction, add dilute hydrochloric acid to adjust the pH of the solution to 3.5-4 to precipitate. After filtering, the product is recrystallized with ethanol to obtain triazinyl lysine; Step 2: Add triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stir and mix, then add p-toluenesulfonic acid catalyst, react at 90-110°C for 4-7h, wash and dry to obtain intermediate 1; Step 3: Add the intermediate 1,3-chloro-1-propanol to acetone solvent, stir evenly, react at 65-85°C for 2-6 hours, and then perform rotary distillation to obtain a quaternized triazine chain extender; Step 4: Add toluene diisocyanate and polyether polyol to a reactor, then add dibutyltin dilaurate catalyst, and carry out prepolymerization under a nitrogen atmosphere at a temperature of 75-95°C for 2-3 hours. Then add a quaternized triazine chain extender, stir and carry out a chain extension reaction at 40-65°C for 20-25 minutes. After the reaction is completed, cool naturally to obtain a quaternized triazine polyurethane. The preparation method of the modified cyclodextrin is: S1. 15-20 parts by weight of thionyl chloride and 12-14 parts by weight of triazine-lysine were added to the reactor, and the reaction was carried out at 65-85 ° C for 4-8h. After completion, the mixture was cooled to room temperature, concentrated under reduced pressure, washed with petroleum ether, and dried to obtain triazine-lysine chloride; S2. Add 5-8 parts by weight of triazine lysine chloride and 12-18 parts by weight of β-cyclodextrin to N,N-dimethylformamide solvent, stir and disperse, continue to add 0.1-0.2 parts by weight of triethylamine catalyst, react at 70-90°C for 6-10h, and then distill under reduced pressure and wash to obtain modified cyclodextrin.

2. The durable concrete according to claim 1, characterized in that In the step 1, the mass ratio of 2,4,6-tris(4-formaldehydephenyl)-1,3,5-triazine, L-lysine, and sodium borohydride is 1:1.8-2.3:0.2-0.

5.

3. The durable concrete according to claim 1, characterized in that In the step 2, the mass ratio of triazine lysine, 3-dimethylamino-1-propanol, and p-toluenesulfonic acid catalyst is 0.4-0.6:1:0.01-0.

03.

4. The durable concrete according to claim 1, characterized in that The mass ratio of the intermediate 1 and 3-chloro-1-propanol in the step 3 is 1:1.2-1.

5.

5. The durable concrete according to claim 1, characterized in that In the step 4, the mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst, and quaternized triazine chain extender is 1:1.1-1.3:0.01-0.03:0.4-0.

6.

6. A method for preparing the durable concrete according to any one of claims 1 to 5, characterized in that: The preparation method of the durable concrete comprises the following steps: adding cement, crushed stone, fly ash, polycarboxylate water reducer, quaternized triazine-based polyurethane, modified cyclodextrin and water into a mixer, stirring evenly for 50-100 seconds to obtain the durable concrete.

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