A method for preparing a protective agent for improving the protective ability of cement concrete

Abstract

The present invention provides a method for preparing a protective agent for improving the protective ability of cement concrete, and relates to the technical field of cement concrete protection. The method comprises raw materials and proportions, wherein polyacrylic acid (PAA) is selected as the main component, and its content is 10%-30%, nano silicon dioxide (SiO2) is selected as the nano material, and its average particle size is 10-50 nanometers, and its content is 1%-5%, and polyethylene glycol (PEG) is selected as the modifier, and its relative molecular mass is 2000-8000, and its content is 2%-5%. In the present invention, compared with the prior art, the technical scheme can significantly improve the protective performance of cement concrete by introducing the cement concrete protective agent optimized by nano materials. The addition of nano silicon dioxide enhances the improvement of the interface bonding force and the microstructure, and the modification of polyacrylic acid and polyethylene glycol further improves the impermeability and chemical erosion resistance, so that the durability of cement concrete in harsh environments is significantly enhanced, and compared with traditional protective agents, its service life and protective effect have a qualitative leap.

Description

Technical Field

[0001] The invention relates to the technical field of cement concrete protection, and in particular to a method for preparing a protective agent for improving the protective ability of cement concrete. Background Art

[0002] Cement concrete is indispensable in large-scale construction. Since its introduction, it has been the most important structural material in construction projects. It supports building structures with excellent performance, and its safety also directly affects people's lives and property safety. However, most cement concrete bridges, culverts and other buildings are exposed to the sun, rain, freeze-thaw, corrosion and other damages all year round without any protection, resulting in repeated damages such as reduced strength, stains, peeling, exposed steel bars, etc., resulting in a shortened service life, and many precious building materials are even scrapped prematurely.

[0003] Water damage is one of the biggest hazards of cement concrete. If the water permeability coefficient is too large, it will easily cause freeze-thaw damage and steel corrosion, which may cause surface damage at the least and steel corrosion and concrete peeling at the worst, just like "boneless roasted chicken", posing a huge safety hazard. After spraying "concrete protector", its active ingredients will generate water-insoluble crystals with concrete, fill and seal gaps, and form a deep water-repellent layer, making the surface of cement concrete impervious to water. Its active chemical components penetrate into the concrete, catalyze the formation of water-insoluble crystals in the concrete, fill and seal capillaries and shrinkage cracks, and form a waterproof layer with a certain depth, thereby improving the waterproof ability of cement concrete itself.

[0004] However, in the prior art, many cement concrete protective agents mainly rely on traditional silicate materials, such as silicate cement and mineral admixtures. Although these materials can provide a certain protective effect, their protective performance is relatively limited, especially in the face of chemical erosion, salt penetration and extreme climatic conditions, it is often difficult to meet the requirements of long-term durability. In addition, these protective agents have limited effect on the improvement of the microstructure of cement concrete, resulting in insufficient impermeability and crack resistance; some existing cement concrete protective agents may contain environmentally harmful chemicals such as volatile organic compounds (VOCs) and heavy metals during production and use. These substances not only pose a threat to the health of construction workers, but also may infiltrate into soil and water sources during use, causing environmental pollution. In addition, some protective agents in the prior art may require complex processing processes during construction, increase energy consumption and waste generation, and are not conducive to achieving green buildings and sustainable development goals. Therefore, technicians in this field provide a method for preparing a protective agent that improves the protective ability of cement concrete to solve the problems raised in the above background technology. Summary of the invention

[0005] In view of the shortcomings of the existing technology, many existing cement concrete protective agents mainly rely on traditional silicate materials, such as silicate cement and mineral admixtures. Although these materials can provide a certain protective effect, their protective performance is relatively limited, especially in the face of chemical erosion, salt penetration and extreme climatic conditions, it is often difficult to meet the requirements of long-term durability. In addition, these protective agents have limited effect on improving the microstructure of cement concrete, resulting in insufficient impermeability and crack resistance; some existing cement concrete protective agents may contain environmentally harmful chemicals such as volatile organic compounds (VOCs) and heavy metals during production and use. These substances not only pose a threat to the health of construction workers, but also may penetrate into the soil and water sources during use, causing environmental pollution. In addition, some protective agents in the existing technology may require complex treatment processes during construction, which increases energy consumption and waste generation, and is not conducive to achieving green building and sustainable development goals.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: The present invention provides a method for preparing a protective agent for improving the protective ability of cement concrete, including raw materials and proportions, the raw materials and proportions include 150 parts of polysiloxane resin, 100 parts of polyurea resin, and 70 parts of epoxy resin, the raw materials and proportions also include nanomaterials, the nanomaterials include 10 parts of nano silicon dioxide (SiO2), 1 part of nano carbon tubes (CNT), 5 parts of nano zinc oxide (ZnO), and 2 parts of graphene nanosheets (GNP), the raw materials and proportions also include a modifier, and the modifier includes a hydrophilic modified The raw materials and the proportions also include a solvent, the solvent is acetone, and the acetone is added in an appropriate amount to dissolve the resin and part of the modifier. The raw materials and the proportions also include a curing agent, the curing agent is xylene diisocyanate (TDI), and the curing agent is added in an appropriate amount to cure the resin. The raw materials and the proportions also include a stabilizer, and the stabilizer is 2 parts of polyethylene glycol (PEG) to improve storage stability and prolong reaction time.

[0007] Preferably, the method comprises the following steps, characterized in that:

[0008] S1. The polysiloxane resin, polyurea resin and epoxy resin are mixed in the above proportions and stirred evenly in a high-speed mixer;

[0009] S2. Add nano-silicon dioxide, carbon nanotubes, nano-zinc oxide and graphene nanosheets to the mixed resin in the above proportions, and disperse them using an ultrasonic disperser to ensure uniform distribution of the nanomaterials;

[0010] S3. Add a hydrophilic modifier, an antibacterial / antifungal compound and a silane coupling agent, and continue stirring evenly in the above proportions;

[0011] S4. Acetone is gradually added to the mixture to dissolve the resin and part of the modifier, while stirring in the above proportions;

[0012] S5. Add TDI as a curing agent in the above ratio of resin and curing agent and stir evenly; S6. Add polyethylene glycol and stir evenly in the above ratio to increase the storage stability of the protective agent and prolong the reaction time with cement concrete;

[0013] S7. Filter the mixed protective agent to remove undissolved solid particles;

[0014] S8. Pour the filtered protective agent into the mold, control the temperature at 40°C for thermal curing, and the curing time is 2 hours.

[0015] Preferably, the composite ratio of the nanomaterials is 5%-20% for nano-silicon dioxide, 0.5%-2% for nano-carbon tubes, and 1%-5% for nano-zinc oxide. The selected ratio of the modifiers is 1%-5% for hydrophilic modifiers, 0.1%-1% for antibacterial agents, and 0.1%-1% for mildewproof agents. During the curing process, the solvent evaporation temperature is controlled at 30-70°C, and the thermal curing temperature is controlled at 100-150°C.

[0016] Preferably, the prepared protective agent has the following properties:

[0017] Waterproof rate is greater than 98%;

[0018] Compressive strength greater than 10MPa;

[0019] Chemical corrosion resistance meets ISO12007-2 standards;

[0020] The UV resistance time is greater than 2000 hours.

[0021] Preferably, the nano silicon dioxide is used to improve the filling property and reduce the porosity of the protective agent, the nano carbon tube is used to enhance the conductivity and antistatic property of the protective agent, and the nano zinc oxide is used to enhance the ultraviolet shielding effect of the protective agent.

[0022] Preferably, the hydrophilic modifier improves the permeability and adhesion of the protective agent, the antibacterial agent enhances the antibacterial property of the protective agent, and the mildew-proof agent improves the mildew-proof property of the protective agent.

[0023] Preferably, in the mixing step, the amount of nano-silicon dioxide (SiO2) added is 1%-5% of the total amount of the polymer material. In the curing step, the curing time is 24-48 hours. After the slurry is evenly mixed, the curing and molding should be completed within 1 hour.

[0024] Preferably, the protective agent has the following properties:

[0025] The average water absorption rate is 2.21x10'mm / min';

[0026] Fire resistance performance (standard temperature rise, fire resistance test time) 4h;

[0027] Wear resistance improvement value % baseline 2.34, tested 2.62;

[0028] Acid resistance 10%, no abnormality in H2SO4 for 240h;

[0029] Alkali resistance 10%, no abnormality in NaOH 240h;

[0030] Stain resistance 8%;

[0031] Artificial accelerated aging 3000h;

[0032] Drying time (h): surface dry ≤ 0.5, actual dry ≤ 3;

[0033] Artificial accelerated aging (3000h) does not cause blistering, shedding or powdering;

[0034] The average reduction effect of chloride absorption was 90.4%;

[0035] Air permeability [g / (m2.d)] 83;

[0036] Washability (times) ≥11000.

[0037] Preferably, the protective agent has the following properties:

[0038] The average water absorption rate is ≤0.01mm / min1 / 2;

[0039] Fire resistance performance (standard temperature rise, fire resistance test time) ≥ 2h;

[0040] Improved wear resistance %≥10;

[0041] Acid resistance 10%, H2SO4 240h no abnormality;

[0042] Alkali resistance 10%, no abnormality in NaOH for 240h;

[0043] Stain resistance (%) ≤ 10;

[0044] Artificial accelerated aging (h) 1000 / 3000;

[0045] Drying time (h): surface dry ≤ 2, actual dry ≤ 24;

[0046] Artificial accelerated aging (3000h) does not cause blistering, shedding or powdering;

[0047] The average value of the reduction effect of chloride absorption is ≥90%;

[0048] Air permeability [g / (m2.d)] ≥80;

[0049] Washability ≥1000.

[0050] Preferably, the polymer material, nanomaterial and modifier are mixed evenly, the mixture is mixed with cement, sand and water in a certain proportion, stirred evenly to form a slurry, and the slurry is poured into a mold and solidified into a shape.

[0051] Preferably, it is composed of the following components by weight: polymer material: polyacrylic acid (PAA) 10%-30%, nanomaterial: nano silicon dioxide (SiO2) 1%-5%, modifier: polyethylene glycol (PEG) 2%-5%, cement: ordinary silicate cement 60%-80%, sand: river sand 5%-15%, water: appropriate amount of deionized water.

[0052] Preferably, the addition of nano-silicon dioxide can enhance the physical and chemical stability of cement concrete, improve its corrosion resistance and wear resistance, and the modification effect of polyethylene glycol can improve the anti-permeability of cement concrete and prevent the penetration of moisture and chemical substances.

[0053] Preferably, the optimized protective agent can significantly improve the durability of cement concrete and extend the service life of the building. The protective agent prepared in this solution is easy to construct and can meet the requirements of on-site construction.

[0054] Preferably, the prepared protective agent is subjected to performance tests, including water absorption, fire resistance, abrasion resistance, acid and alkali resistance, stain resistance, artificial accelerated aging, drying time, air permeability and scrub resistance.

[0055] Preferably, the polymer material: polyacrylic acid (PAA) is selected as the main component, and its content is 10%-30%.

[0056] Nanomaterials: Nano silicon dioxide (SiO2) is selected as the nanomaterial, with an average particle size of 10-50 nanometers and a content of 1%-5%.

[0057] Modifier: Polyethylene glycol (PEG) is selected as the modifier, with a molecular weight of 2000-8000 and a content of 2%-5%.

[0058] Cement: Ordinary Portland cement is used, with a content of 60%-80%.

[0059] Sand: Use river sand with a content of 5%-15%.

[0060] Water: Use deionized water and add appropriate amount.

[0061] Preferably, the physicochemical characteristics in this solution are: physical state: colorless, transparent alkaline liquid, soluble in water; odor: odorless; stability: can be stored for a long time and transported under normal conditions; flash point: non-combustible.

[0062] The present invention provides a method for preparing a protective agent for improving the protective ability of cement concrete. It has the following beneficial effects:

[0063] 1. In the present invention, compared with the prior art, the technical solution can significantly improve the protective performance of cement concrete by introducing cement concrete protective agents optimized by nano materials. The addition of nano-silicon dioxide enhances the interface bonding force and the improvement of microstructure, while the modification of polyacrylic acid and polyethylene glycol further improves the impermeability and chemical corrosion resistance, thereby significantly enhancing the durability of cement concrete in harsh environments. Compared with traditional protective agents, its service life and protective effect have made a qualitative leap.

[0064] 2. In the present invention, the protective agent prepared by this technical solution not only improves the protective ability of cement concrete, but also reduces the maintenance cost of buildings. Due to the excellent performance of the protective agent, the frequent maintenance of buildings due to corrosion, leakage and other problems is reduced, thereby reducing the cost of long-term maintenance and repair. In addition, due to the ease of construction and good environmental performance of the protective agent, the waste of resources and environmental pollution in the construction process are also reduced, achieving a win-win situation of economic and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 A schematic diagram of raw materials and proportions of a method for preparing a protective agent for improving the protective ability of cement concrete according to the present invention;

[0066] Figure 2 A schematic diagram of a raw material framework of a method for preparing a protective agent for improving the protective ability of cement concrete according to the present invention;

[0067] Figure 3 A schematic diagram of technical data of a method for preparing a protective agent for improving the protective ability of cement concrete according to the present invention;

[0068] Figure 4 It is a schematic diagram of the physical and chemical characteristics of a method for preparing a protective agent for improving the protective ability of cement concrete according to the present invention. DETAILED DESCRIPTION

[0069] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0070] Embodiment 1:

[0071] refer to Figure 1-Figure 2 Although existing cement concrete protective agents can improve the durability of cement concrete to a certain extent, they often have problems such as insufficient waterproof performance, poor chemical corrosion resistance, and limited durability. This embodiment provides a method for preparing a protective agent that improves the protective ability of cement concrete, and significantly improves the performance of the protective agent by introducing nanomaterials, special modifiers, and environmentally friendly curing technology.

[0072] Implementation steps:

[0073] Raw material preparation: prepare 150 parts of polysiloxane resin, 100 parts of polyurea resin, 70 parts of epoxy resin, 10 parts of nano-silicon dioxide, 1 part of nano-carbon tubes, 5 parts of nano-zinc oxide, 2 parts of graphene nanosheets, 3 parts of hydrophilic modifier, 1 part of antibacterial / antifungal composite agent, 2 parts of silane coupling agent, appropriate amount of acetone, appropriate amount of TDI and appropriate amount of polyethylene glycol according to the above formula ratio.

[0074] Mixing and dispersion: Mix 150 parts of polysiloxane resin, 100 parts of polyurea resin and 70 parts of epoxy resin, and stir evenly using a high-speed stirrer. Subsequently, add 10 parts of nano-silicon dioxide, 1 part of nano-carbon tubes, 5 parts of nano-zinc oxide and 2 parts of graphene nanosheets to the mixture and disperse it using an ultrasonic disperser.

[0075] Adding modifier and solvent: Add 3 parts of hydrophilic modifier, 1 part of antibacterial / antifungal compound and 2 parts of silane coupling agent to the mixture, continue to stir evenly, then gradually add appropriate amount of acetone to dissolve the resin and part of the modifier.

[0076] Curing agent and stabilizer: Add TDI as curing agent in appropriate proportion and add polyethylene glycol, and stir evenly.

[0077] Filtration and curing: Filter the mixed protective agent to remove undissolved solid particles, then pour the filtered protective agent into the mold and heat cure it at 40°C for 2 hours.

[0078] Performance testing: The prepared protective agent is tested for waterproof rate, compressive strength, chemical corrosion resistance, UV irradiation resistance time and antibacterial / anti-mildew performance.

[0079] Results: The prepared protective agent exhibited excellent waterproof performance (waterproof rate greater than 99%), compressive strength (greater than 12MPa), chemical corrosion resistance (reaching ISO12007-2 standard), UV resistance time (greater than 2500 hours) and antibacterial / antifungal properties (in line with GB15979-2002 standard).

[0080] Applying this protective agent to the surface of cement concrete structures can effectively improve their durability, extend their service life and reduce maintenance costs.

[0081] Embodiment 2:

[0082] refer to Figure 1-Figure 2 , the following are the material ratio parameters of the nanocomposite cement concrete protective agent in this embodiment:

[0083] Material name ratio (mass ratio):

[0084] Polysiloxane resin 40%;

[0085] Polyurea resin 30%;

[0086] Epoxy resin 20%;

[0087] Nano silicon dioxide 5%;

[0088] Carbon nanotubes 3%;

[0089] Nano zinc oxide 2%;

[0090] Graphene nanosheets 2%;

[0091] Hydrophilic modifier 1%;

[0092] Antibacterial / antifungal compound 1%;

[0093] Silane coupling agent 0.5%;

[0094] Acetone 10%;

[0095] Triphenylmethane diisocyanate TDI 2%;

[0096] Polyethylene glycol PEG2%.

[0097] Preparation steps, raw material preparation: prepare the experimental materials according to the above ratio.

[0098] Mixing and dispersing:

[0099] The polysiloxane resin, polyurea resin and epoxy resin are mixed and stirred evenly using a high-speed mixer.

[0100] Nano-silicon dioxide, nano-carbon tubes, nano-zinc oxide and graphene nanosheets are added to the mixture and dispersed using an ultrasonic disperser to ensure that the nanomaterials are evenly dispersed.

[0101] Adding modifiers and solvents:

[0102] Add the hydrophilic modifier, antibacterial / antifungal compound and silane coupling agent into the mixture and continue stirring until evenly mixed.

[0103] Gradually add acetone to dissolve the resin and part of the modifier until the mixture reaches a suitable viscosity.

[0104] Curing agent and stabilizer:

[0105] Add TDI as a curing agent according to the proportion, and add polyethylene glycol, and stir evenly to enhance the stability and curing speed of the protective agent.

[0106] Filtration and curing:

[0107] The mixed protective agent is filtered to remove undissolved solid particles.

[0108] Pour the filtered protective agent into the mold and heat cure at 40 °C for 2 h to ensure that the protective agent is fully cured.

[0109] Performance Testing:

[0110] The prepared protective agent was tested for waterproof rate, compressive strength, chemical corrosion resistance, UV irradiation resistance time and antibacterial / antifungal properties.

[0111] Results and analysis, protective agent performance test results:

[0112] Waterproof rate: greater than 99%;

[0113] Compressive strength: greater than 12MPa;

[0114] Chemical corrosion resistance: meet ISO12007-2 standard;

[0115] UV irradiation resistance time: more than 2500 hours;

[0116] Antibacterial / anti-mildew performance: in line with GB15979-2002 standard;

[0117] Building structure coating performance test results:

[0118] Waterproof rate: greater than 98%;

[0119] Compressive strength: greater than 11MPa;

[0120] Chemical corrosion resistance: meet ISO12007-2 standard;

[0121] UV irradiation resistance time: more than 2400 hours;

[0122] Antibacterial / anti-mildew performance: in line with GB15979-2002 standard.

[0123] in conclusion:

[0124] This embodiment successfully prepared a nano-composite cement concrete protective agent by optimizing the material ratio and preparation process. The protective agent has excellent waterproof performance, compressive strength, chemical corrosion resistance, ultraviolet irradiation resistance and antibacterial / mildew resistance, and can effectively improve the durability of cement concrete structures. The experimental results show that this embodiment provides a method for preparing a cement concrete protective agent with practical application value, which is suitable for the protection and repair of building structures.

[0125] Embodiment three:

[0126] refer to Figure 3 , mix PAA and SiO2 in a certain proportion, add appropriate amount of PEG modifier and stir evenly.

[0127] Mix the mixture with cement, sand and water in a certain proportion and stir well to form a slurry.

[0128] Pour the slurry into the mold and solidify it into shape.

[0129] Performance Test:

[0130] Water absorption test: carried out in accordance with JTJ275-2000 standard.

[0131] Fire resistance test: carried out in accordance with CB28375-2012 standard.

[0132] Abrasion resistance test: carried out in accordance with GB / T16925-1997 standard.

[0133] Acid and alkali resistance test: carried out in accordance with JT / E695-2007 standard.

[0134] Stain resistance test: carried out in accordance with HG / T3792-2014 standard.

[0135] Artificial accelerated aging test: carried out in accordance with JT / E695-2007 standard.

[0136] Drying time test: in accordance with JT / E695-2007 standard.

[0137] Artificial accelerated aging (long-term) test: carried out in accordance with JT / E695-2007 standard.

[0138] Chloride absorption reduction effect test: carried out in accordance with JTJ275-2000 standard.

[0139] Air permeability test: carried out in accordance with T / CECS476-2017 standard.

[0140] Washability test: carried out in accordance with JG / 26-2002 standard.

[0141] Experimental results:

[0142] Average water absorption rate: ≤0.01mm / min1 / 2, actual test value is 2.21x10-6mm / min1 / 2.

[0143] Fire resistance: ≥2h, actual test value is 4h.

[0144] Improved wear resistance: ≥10%, actual test value is 2.34%.

[0145] Acid resistance (10%, H2SO4): No abnormality after 240h.

[0146] Alkali resistance (10%, NaOH): No abnormality after 240h.

[0147] Stain resistance: ≤10%, actual test value is 8%.

[0148] Artificial accelerated aging (1000 / 3000h): no blistering, no falling off, no chalking.

[0149] Drying time: surface drying ≤2h, actual drying ≤24h.

[0150] Artificial accelerated aging (3000h): no blistering, no falling off, no powdering.

[0151] The average value of the chloride absorption reduction effect is ≥90%, and the actual test value is 90.4%.

[0152] Air permeability: [g / (m2.d)] ≥80, actual test value is 83.

[0153] Washability: ≥1000 times, actual test value is 11000 times.

[0154] in conclusion:

[0155] The high-performance cement concrete protective agent prepared in this embodiment meets or exceeds the relevant standard requirements in various performance tests, proving the excellent performance of the protective agent in terms of water absorption, fire resistance, wear resistance, acid and alkali resistance, stain resistance, artificial accelerated aging, drying time, artificial accelerated aging (long-term), chloride absorption reduction effect and air permeability. The physical and chemical characteristics in this scheme are physical state: colorless, transparent alkaline liquid, soluble in water; odor: odorless; stability: can be stored for a long time and transported under normal conditions; ignition point: non-combustible.

[0156] Working principle: Nanomaterials play an important role in improving the protective ability of cement concrete due to their unique physical and chemical properties. The following is the working principle of nanomaterials in protective agents:

[0157] Enhance interfacial bonding: Nano-silicon dioxide (SiO2) has a large specific surface area and excellent chemical stability, and can form a good interfacial bonding with the cement matrix, thereby improving the overall strength and durability of cement concrete, and improving the microstructure: The addition of nano-silicon dioxide can fill the pores in the cement matrix, improve its microstructure, and reduce the porosity, thereby improving the impermeability of cement concrete, and inhibit alkali-aggregate reaction: The addition of nano-silicon dioxide can inhibit alkali-aggregate reaction, reduce the expansion rate of cement concrete, and improve its durability. Improve resistance to chemical corrosion: The addition of nano-silicon dioxide can improve the chemical corrosion resistance of cement concrete and reduce the corrosion of chemical substances such as sulfates and chloride ions.

[0158] The polymer material plays a modifying role in the protective agent. The following is the working principle of the polymer material:

[0159] Improve impermeability: Polyacrylic acid (PAA), as a polymer material, has good impermeability. Its addition can fill the pores in the cement matrix, reduce the porosity, and improve the impermeability of cement concrete. Improve mechanical properties: Polyacrylic acid can improve the mechanical properties of cement concrete, such as compressive strength and flexural strength. Improve durability: Polyacrylic acid can improve the durability of cement concrete and reduce its chemical corrosion such as alkali-aggregate reaction and sulfate corrosion.

[0160] As a modifier, polyethylene glycol (PEG) plays the following roles in protective agents: Improving interfacial bonding: Polyethylene glycol can improve the interfacial bonding between nano-silica and cement matrix, thereby improving the overall strength and durability of cement concrete, and improving the microstructure: Polyethylene glycol can fill the pores in the cement matrix, improve its microstructure, reduce porosity, and improve the impermeability of cement concrete. Improve chemical corrosion resistance: Polyethylene glycol can improve the chemical corrosion resistance of cement concrete and reduce the corrosion of chemical substances such as sulfates and chloride ions.

[0161] The preparation method is to mix the polymer material, nano material and modifier in a certain proportion, stir evenly, mix the mixed material with cement, sand and water in a certain proportion, continue to stir evenly to form a slurry, pour the slurry into a mold, control the curing conditions such as temperature, humidity and curing time, usually 24-48 hours, and perform performance tests on the prepared protective agent, including water absorption, fire resistance, wear resistance, acid and alkali resistance, stain resistance, artificial accelerated aging, drying time, air permeability and washability.

[0162] Through the above working principle and preparation method, the nanomaterial optimized cement concrete protective agent can effectively improve the protective ability of cement concrete, providing a new type of protective material for the construction industry. The protective agent has significant advantages in improving the durability, impermeability and chemical corrosion resistance of cement concrete, and has broad application prospects.

[0163] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention. Finally, it should be noted that the foregoing are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it will be still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention as defined by the appended claims and their equivalents.

Claims

1. A method for preparing a protective agent for improving the protective ability of cement concrete, characterized in that: The raw materials and proportions for preparing the protective agent include 150 parts of polysiloxane resin, 100 parts of polyurea resin, and 70 parts of epoxy resin. The raw materials and proportions also include nanomaterials, which include 10 parts of nano silicon dioxide SiO2, 1 part of nano carbon tubes CNT, 5 parts of nano zinc oxide ZnO, and 2 parts of graphene nanosheets GNP. The raw materials and proportions also include modifiers, which include 3 parts of hydrophilic modifier polyethylene PVA, 1 part of antibacterial / antifungal compound triclosan and benzoic acid complex, and 2 parts of environmentally friendly penetration enhancer silane coupling agent. The raw materials and proportions also include solvents, which use acetone as the solvent, and which are added in an appropriate amount to dissolve the resin and part of the modifiers. The raw materials and proportions also include curing agents, which use xylene diisocyanate TDI as the curing agent, and which are added in an appropriate amount to cure the resin. The raw materials and proportions also include stabilizers, which use polyethylene glycol PEG as the stabilizer. 2 parts, used to improve storage stability and extend reaction time.

2. A method for preparing a protective agent for improving the protective ability of cement concrete according to claim 1, comprising the following steps, characterized in that: S1. The polysiloxane resin, polyurea resin and epoxy resin are mixed in the above proportions and stirred evenly in a high-speed mixer; S2. Add nano-silicon dioxide, carbon nanotubes, nano-zinc oxide and graphene nanosheets to the mixed resin in the above proportions, and disperse them using an ultrasonic disperser to ensure uniform distribution of the nanomaterials; S3. Add a hydrophilic modifier, an antibacterial / antifungal compound and a silane coupling agent, and continue stirring evenly in the above proportions; S4. Acetone is gradually added to the mixture to dissolve the resin and part of the modifier, while stirring in the above proportions; S5. According to the above ratio of resin and curing agent, add TDI as curing agent and stir evenly; S6. Add polyethylene glycol and stir evenly in the above ratio to increase the storage stability of the protective agent and prolong the reaction time with cement concrete; S7. Filter the mixed protective agent to remove undissolved solid particles; S8. Pour the filtered protective agent into the mold, control the temperature at 40°C for thermal curing, and the curing time is 2 hours.

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