Durable concrete and preparation method thereof

Abstract

The invention relates to the technical field of concrete, and discloses durable concrete and a preparation method thereof.The durable concrete is obtained by adding cement, gravel, fly ash, a polycarboxylate superplasticizer, quaternized triazinyl polyurethane, modified cyclodextrin and water into a stirrer and stirring the materials evenly. A quaternary ammonium salt group in the quaternized triazinyl polyurethane can effectively reduce the adsorption of the clay to the water reducing agent, so that the mixing amount of an additive is reduced, and the working performance and durability of the concrete are improved; wherein the triazinyl group has certain chemical stability and corrosion resistance, so that chlorine salt erosion of the concrete in a severe environment is reduced, and the service life of the concrete is prolonged.

Description

Technical Field

[0001] The 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 that are made of cementitious materials to bind aggregates into a whole. Cement concrete has the characteristics of easy availability of raw materials, convenient construction, and low cost. During long-term use, pavement concrete will be penetrated and corroded by chloride ions, thus affecting its durability. For example, patent CN118878269A discloses a durable concrete and its preparation method. The invention adopts lithium carbonate modified silicone emulsion in combination with other components to make the concrete have high durability (impermeability and resistance to chloride ion penetration), but its components are relatively simple and the durability needs to be further improved. Summary of the invention

[0003] 1. Technical issues to be resolved

[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] (II) Technical solution

[0006] To achieve the above object, the present invention provides the following technical solution: a durable concrete, comprising the following weight components: 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;

[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 for reaction for 6-8h, cool to room temperature, add sodium borohydride, react for 2-4h, add dilute hydrochloric acid after the reaction to adjust the pH of the solution to 3.5-4, precipitate, filter the product, and recrystallize it with ethanol to obtain triazine lysine;

[0009] Step 2: Add triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stir and mix, continue to add p-toluenesulfonic acid catalyst, react at 90-110° C. for 4-7 hours, wash and dry after reaction 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 2-6h, and after the reaction, perform rotary distillation to obtain a quaternary ammonium triazine-based 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-based chain extender and stir to carry out a chain extension reaction. React at 40-65°C for 20-25min. After the reaction is completed, cool naturally to obtain a quaternized triazine-based polyurethane.

[0012] Preferably, in step 1, the mass ratio of 2,4,6-tris(4-formylphenyl)-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, in step three, the mass ratio of the intermediate 1 to 3-chloro-1-propanol is 1:1.2-1.5.

[0015] Preferably, in 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. Add 15-20 parts by weight of thionyl chloride and 12-14 parts by weight of triazine lysine to the reactor, react at 65-85 ° C for 4-8h, cool to room temperature after completion, concentrate under reduced pressure, wash with petroleum ether, and dry 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 method for preparing the durable concrete is: adding cement, crushed stone, fly ash, polycarboxylic acid water reducer, quaternized triazine-based polyurethane, modified cyclodextrin, and water into a mixer, stirring evenly for 50-100 seconds to obtain the durable concrete.

[0020] (III) Beneficial technical effects

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

[0022] The quaternary ammonium salt group in the quaternary ammonium triazine-based polyurethane can effectively reduce the adsorption of clay on the water reducer, thereby reducing the dosage of the admixture and improving the working performance and durability of the concrete; the triazine group therein has certain chemical stability and corrosion resistance, which helps to reduce the chloride salt erosion of the concrete in harsh environments, thereby extending the service life of the concrete; the polyurethane itself can also improve the durability of the concrete; the acyl chloride group in the acyl chloride triazine lysine reacts with the hydroxyl group in β-cyclodextrin to obtain modified cyclodextrin, while increasing the degree of substitution of cyclodextrin. Cyclodextrin can improve the density of concrete, thereby further improving the durability of concrete. DETAILED DESCRIPTION

[0023] Example 1

[0024] (1) adding 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heating to 30° C. for reaction for 6 h, cooling to room temperature, adding 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, reacting for 2 h, adding dilute hydrochloric acid after the reaction to adjust the pH of the solution to 3.5, precipitating a precipitate, filtering the product and recrystallizing it with ethanol to obtain triazine lysine;

[0025] (2) adding triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stirring and mixing, and continuously adding p-toluenesulfonic acid catalyst thereto, wherein the mass ratio of triazine lysine, 3-dimethylamino-1-propanol, and p-toluenesulfonic acid catalyst is 0.4:1:0.01, reacting at 90° C. for 4 h, washing after completion, and drying to obtain intermediate 1;

[0026] (3) adding the intermediate 1 and 3-chloro-1-propanol to an acetone solvent, wherein the mass ratio of the intermediate 1 and 3-chloro-1-propanol is 1:1.2, stirring evenly, reacting at 65° C. for 2 h, and after the reaction, rotary distilling to obtain a quaternary ammonium triazine-based chain extender;

[0027] (4) adding toluene diisocyanate and polyether polyol into a reaction kettle, adding dibutyltin dilaurate catalyst, and prepolymerizing under a nitrogen atmosphere at a temperature of 75° C. for 2 h, and then adding a quaternized triazine chain extender, wherein the mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst, and quaternized triazine chain extender is 1:1.1:0.01:0.4, stirring for chain extension reaction, reacting at 40° C. for 20 min, and cooling naturally after the reaction is completed to obtain a quaternized triazine polyurethane;

[0028] (5) adding 15 parts by weight of thionyl chloride and 12 parts by weight of triazine lysine to a reactor, reacting at 65° C. for 4 h, cooling to room temperature after the reaction, concentrating under reduced pressure, washing with petroleum ether, and drying 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) adding 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heating to 45° C. for reaction for 8 h, cooling to room temperature, adding 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, reacting for 4 h, adding dilute hydrochloric acid after the reaction to adjust the pH of the solution to 4, precipitating a precipitate, filtering the product and recrystallizing it with ethanol to obtain triazine lysine;

[0033] (2) adding triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stirring and mixing, and continuously adding 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, reacting at 110° C. for 7 h, washing after reaction, and drying to obtain intermediate 1;

[0034] (3) adding the intermediate 1, 3-chloro-1-propanol to an acetone solvent, wherein the mass ratio of the intermediate 1, 3-chloro-1-propanol is 1:1.5, stirring evenly, reacting at 85° C. for 6 hours, and after the reaction, rotary distilling to obtain a quaternary ammonium triazine-based chain extender;

[0035] (4) adding toluene diisocyanate and polyether polyol into a reactor, adding dibutyltin dilaurate catalyst, and prepolymerizing under a nitrogen atmosphere at a temperature of 95° C. for 3 h, and then adding a quaternized triazine chain extender, wherein the mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst, and quaternized triazine chain extender is 1:1.3:0.03:0.6, stirring for chain extension reaction, reacting at 65° C. for 25 min, and cooling naturally after the reaction is completed to obtain a quaternized triazine polyurethane;

[0036] (5) adding 20 parts by weight of thionyl chloride and 14 parts by weight of triazine lysine to a reactor, reacting at 85° C. for 8 h, cooling to room temperature after reaction, concentrating under reduced pressure, washing with petroleum ether, and drying 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, 100 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) adding 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heating to 35° C. for reaction for 7 hours, cooling to room temperature, adding 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, reacting for 3 hours, adding dilute hydrochloric acid after the reaction to adjust the pH of the solution to 3.8, precipitating a precipitate, filtering the product and recrystallizing it with ethanol to obtain triazine lysine;

[0041] (2) adding triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stirring and mixing, and continuously adding p-toluenesulfonic acid catalyst thereto, wherein the mass ratio of triazine lysine, 3-dimethylamino-1-propanol, and p-toluenesulfonic acid catalyst is 0.5:1:0.02, reacting at 100° C. for 6 h, washing after completion, and drying to obtain intermediate 1;

[0042] (3) adding the intermediate 1 and 3-chloro-1-propanol to an acetone solvent, wherein the mass ratio of the intermediate 1 and 3-chloro-1-propanol is 1:1.3, stirring evenly, reacting at 75° C. for 4 hours, and after the reaction, rotary distilling to obtain a quaternary ammonium triazine-based chain extender;

[0043] (4) adding toluene diisocyanate and polyether polyol into a reactor, adding dibutyltin dilaurate catalyst, and prepolymerizing under a nitrogen atmosphere at a temperature of 85° C. for 2 h, and then adding a quaternized triazine chain extender, wherein the mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst, and quaternized triazine chain extender is 1:1.2:0.02:0.5, stirring for chain extension reaction, reacting at 55° C. for 22.5 min, and cooling naturally after the reaction is completed to obtain a quaternized triazine polyurethane;

[0044] (5) adding 18 parts by weight of thionyl chloride and 13 parts by weight of triazine lysine to a reactor, reacting at 75° C. for 6 h, cooling to room temperature after the reaction, concentrating under reduced pressure, washing with petroleum ether, and drying 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) adding 2,4,6-tris(4-formylphenyl)-1,3,5-triazine and L-lysine to ethanol, heating to 30° C. for reaction for 6 h, cooling to room temperature, adding 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, reacting for 2 h, adding dilute hydrochloric acid after the reaction to adjust the pH of the solution to 3.5, precipitating a precipitate, filtering the product and recrystallizing it with ethanol to obtain triazine lysine;

[0049] (2) adding triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stirring and mixing, and continuously adding p-toluenesulfonic acid catalyst thereto, wherein the mass ratio of triazine lysine, 3-dimethylamino-1-propanol, and p-toluenesulfonic acid catalyst is 0.4:1:0.01, reacting at 90° C. for 4 h, washing after completion, and drying to obtain intermediate 1;

[0050] (3) adding the intermediate 1, 3-chloro-1-propanol to an acetone solvent, wherein the mass ratio of the intermediate 1, 3-chloro-1-propanol is 1:1.5, stirring evenly, reacting at 85° C. for 6 hours, and after the reaction, rotary distilling to obtain a quaternary ammonium triazine-based chain extender;

[0051] (4) adding toluene diisocyanate and polyether polyol into a reactor, adding dibutyltin dilaurate catalyst, and prepolymerizing under a nitrogen atmosphere at a temperature of 95° C. for 3 h, and then adding a quaternized triazine chain extender, wherein the mass ratio of toluene diisocyanate, polyether polyol, dibutyltin dilaurate catalyst, and quaternized triazine chain extender is 1:1.3:0.03:0.6, stirring for chain extension reaction, reacting at 65° C. for 25 min, and cooling naturally after the reaction is completed to obtain a quaternized triazine polyurethane;

[0052] (5) adding 18 parts by weight of thionyl chloride and 13 parts by weight of triazine lysine to a reactor, reacting at 75° C. for 6 h, cooling to room temperature after the reaction, concentrating under reduced pressure, washing with petroleum ether, and drying 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 is different in that no quaternary ammonium triazine-based polyurethane is added.

[0057] Comparative Example 2

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

[0059] Performance Testing

[0060] The obtained concrete was made into a 150mm*150mm*150mm cubic specimen. 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 "Concrete Structure Durability Design Code", the chloride ion diffusion coefficient of a Class E structure with a design life of 100 years should be less than 4×10 -12 m 2 / s.

[0061] Table 1: Performance tests.

[0062]

[0063] It can be seen from Table 1 that 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 only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. 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 for reaction for 6-8h, cool to room temperature, add sodium borohydride, react for 2-4h, add dilute hydrochloric acid after the reaction to adjust the pH of the solution to 3.5-4, precipitate, filter the product, and recrystallize it with ethanol to obtain triazine lysine; Step 2: Add triazine lysine and 3-dimethylamino-1-propanol to N,N-dimethylformamide solvent, stir and mix, continue to add p-toluenesulfonic acid catalyst, react at 90-110° C. for 4-7 hours, wash and dry after reaction 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 2-6h, and after the reaction, perform rotary distillation to obtain a quaternary ammonium 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. The prepolymerization temperature is 75-95°C and the prepolymerization time is 2-3h. Then add a quaternized triazine-based chain extender and stir to carry out a chain extension reaction. React at 40-65°C for 20-25min. After the reaction is completed, cool naturally to obtain a quaternized triazine-based polyurethane.

2. The method for preparing durable concrete according to claim 1, characterized in that: In the step 1, the mass ratio of 2,4,6-tris(4-formylphenyl)-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: In the step 3, the mass ratio of the intermediate 1 to 3-chloro-1-propanol 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. The durable concrete according to claim 1, characterized in that: The preparation method of the modified cyclodextrin is: S1. Add 15-20 parts by weight of thionyl chloride and 12-14 parts by weight of triazine lysine to the reactor, react at 65-85 ° C for 4-8h, cool to room temperature after completion, concentrate under reduced pressure, wash with petroleum ether, and dry 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.

7. A method for preparing the durable concrete according to any one of claims 1 to 6, characterized in that: The preparation method of the durable concrete is as follows: adding cement, crushed stone, fly ash, polycarboxylic acid 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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