Waterborne epoxy downstream surface odor-removing waterproof coating as well as preparation method and application thereof

Abstract

The invention relates to a water-based epoxy downstream face odorless waterproof coating as well as a preparation method and application thereof, and belongs to the technical field of water-based coatings. The water-based epoxy downstream face odorless waterproof coating comprises a component A and a component B, the component A comprises a waterborne epoxy curing agent, a dispersing agent, a defoaming agent, a thickening agent, wear-resistant powder, a pigment and filler mixture, water, an anti-settling auxiliary agent, a wetting leveling agent, a scratch-resistant auxiliary agent and a sterilizing agent; the component B comprises a waterborne epoxy emulsion, a silane coupling agent and a toughening agent; the water-based epoxy curing agent is a modified amine curing agent and comprises epoxy resin E51, polyethylene glycol diglycidyl ether, aliphatic polyamine, a reactive emulsifier, an end-capping reagent and propylene glycol monomethyl ether, the water-based epoxy downstream face odorless waterproof coating is different from a conventional waterproof coating, is specially designed for a humid environment and can be coated and cured on a humid surface, and the water-based epoxy downstream face odorless waterproof coating has the advantages that the coating is environmentally friendly, and the service life of the coating is prolonged. Construction is convenient, real waterproofness of the downstream face is achieved, odor removal and environmental protection are achieved, and the antibacterial and mildew-proof characteristics are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of water-based coatings, and in particular relates to a water-based epoxy back-water surface odor-free waterproof coating, a preparation method and an application thereof. Background Art

[0002] In a building structure, the side that is in direct contact with water is called the "water-facing side", and the opposite side is called the "water-repellent side". Building waterproof materials are a type of protective material used for buildings and structures. Their main function is to prevent moisture and leaks, and protect building structures from erosion and damage by water.

[0003] Moisture-proofing: refers to preventing corrosive substances such as groundwater, water vapor or salt in the foundation from penetrating into the building.

[0004] Leakage prevention: refers to preventing rainwater, snow water, etc. from leaking into the building from the roof, walls or joints of concrete components, as well as preventing water in the water storage structure from leaking outwards.

[0005] Common waterproofing measures currently include:

[0006] Inorganic rigid waterproof coating: can form a protective layer on the surface of the building, but it is heavy, limited by the structure of the construction area, has no permeability, and is easily damaged by mechanical vibration and other factors.

[0007] Waterproofing coating: It has certain permeability, but it is not effective in sealing the pores or larger cracks in the building structure, and has poor long-term water resistance.

[0008] Waterproof roll coating: usually made of modified asphalt or polymer roll, with good expansion ductility and toughness. However, it is an elastomer, and its adhesion to the base layer is insufficient, which easily forms "two skins" and leads to delamination.

[0009] Film waterproof coating: including polymer cement, acrylic acid, polyurethane waterproof coating, etc. These high molecular organic polymer materials have good film-forming and adhesion properties, but have some disadvantages, such as high thermoplasticity, poor solvent resistance, insufficient strength and weather resistance, which directly affect the use effect and service life, and need to be constructed on a dry base surface, otherwise the coating and the base surface cannot be well combined and the coating film cannot be formed. It solves the inherent deficiencies of the coiled material, but due to its own defects, it cannot be constructed on the "backwater surface".

[0010] These materials work better on the water-facing surface, but the waterproof effect will be significantly reduced when applied on the back surface. In addition, waterproof coatings also need to have good adhesion, be able to adapt to dry and wet base surfaces, and have acid and alkali resistance, bacteria and mildew resistance, and environmental protection properties.

[0011] At present, the existing back-water surface waterproof coatings still have problems such as low bonding strength with the substrate, deformation and cracking, and inability to withstand the high penetration water pressure on the back-water surface, as well as poor performance such as water resistance and low-temperature film-forming properties and poor temperature adaptability. The corresponding adverse phenomena such as aging, cracking, breakage, and deformation also need to be urgently solved. In addition, many existing materials still have problems such as strong odor, high toxicity, and poor environmental protection.

[0012] Therefore, it is a current demand to develop an environmentally friendly waterproof coating that can resist the penetration pressure of the back water surface, has excellent anti-seepage performance, strong adhesion and durability. Summary of the invention

[0013] The purpose of the present invention is to solve the problems existing in the prior art and provide a water-based epoxy back-water surface odor-free waterproof coating, a preparation method and its application. The water-based epoxy back-water surface odor-free waterproof coating of the present invention is different from conventional waterproof coatings. It is specially designed for humid environments, can be applied and cured on humid surfaces, is easy to construct, and realizes true back-water surface waterproofing. It is not only odor-free and environmentally friendly, but also has antibacterial and mildew-proof properties.

[0014] The first object of the present invention is:

[0015] Provided is a water-based epoxy back-water surface odorless waterproof coating, which comprises a component A and a component B, wherein the weight ratio of the component A to the component B is 1 to 5:1;

[0016] The A component comprises the following raw materials in percentage by weight:

[0017] Water-based epoxy curing agent 20-50%, dispersant 0.5-2%, defoamer 0.1-2%, thickener 0.1-2%, wear-resistant powder 10-20%, pigment and filler mixture 10-40%, water 10-40%, anti-settling agent 0.01-2%, wetting and leveling agent 0.01-2%, anti-scratch agent 0.01-2%, bactericide 0.01-2%, all components are prepared to 100%;

[0018] The waterborne epoxy curing agent is a modified amine curing agent, which includes:

[0019] Epoxy resin E51, polyethylene glycol diglycidyl ether, aliphatic polyamine, reactive emulsifier, capping agent and propylene glycol methyl ether (PM);

[0020] The weight ratio of the epoxy resin E51: polyethylene glycol diglycidyl ether: aliphatic polyamine is 1-3:2-4:10-15;

[0021] The amount of the reactive emulsifier is 0.5-2% by weight of the aliphatic polyamine;

[0022] The amount of the end-capping agent is 1 to 10% by weight of the aliphatic polyamine;

[0023] The amount of propylene glycol methyl ether (PM) is 5% to 12% of the weight of epoxy resin E51;

[0024] The reactive emulsifier includes sodium acrylamide isopropyl sulfonate and fatty alcohol polyoxyethylene ether;

[0025] The weight ratio of sodium acrylamidoisopropyl sulfonate to fatty alcohol polyoxyethylene ether is 1-5:1-10;

[0026] The end-capping agent includes: o-toluene glycidyl ether (CGE) and C12-14 alkyl glycidyl ether (AGE);

[0027] The weight ratio of o-cresol glycidyl ether (CGE) to C12-14 alkyl glycidyl ether (AGE) is 1-5:1-10;

[0028] The aliphatic polyamine is one or a combination of ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, and diethylaminopropylamine;

[0029] The wear-resistant powder is one or a combination of basalt flakes, glass powder, and barium sulfate;

[0030] The pigment and filler mixture comprises: titanium dioxide, quartz powder, dispersant and silane coupling agent, and the weight ratio of titanium dioxide: quartz powder: dispersant: silane coupling agent is 1-2: 1-2: 0.5: 0.1-0.5;

[0031] The titanium dioxide is a titanium dioxide with aluminum oxide or chromium oxide coated on the surface, wherein the weight percentage of titanium dioxide is 94-95.5%, the oil absorption is 17-20g / 100g, and the whiteness is ≥93%;

[0032] The quartz powder is quartz powder with SiO2 content ≥ 99%;

[0033] The pigment-filler mixture is mixed and preformed into a pigment-filler polymer slurry before use;

[0034] The B component comprises the following raw materials in percentage by weight:

[0035] The aqueous epoxy emulsion is 20-90%, the silane coupling agent is 1-10%, the toughening agent is 1-20%, and all the components are prepared to be 100%.

[0036] The waterborne epoxy back surface odorless waterproof coating of the present invention is further optimized as follows:

[0037] The preparation of the pigment and filler polymer slurry comprises the following steps:

[0038] Titanium dioxide, quartz powder, dispersant and silane coupling agent were charged into a closed ball mill reactor in proportion and ball milled for 16 hours to prepare a pigment filler polymer slurry in a white sludge state with a particle size of 40 to 80 nm.

[0039] The waterborne epoxy back surface odorless waterproof coating of the present invention is further optimized as follows:

[0040] The glass powder is one or a combination of metal oxides: spherical powders made of silicon oxide, aluminum oxide, iron oxide and sodium oxide.

[0041] The waterborne epoxy back surface odorless waterproof coating of the present invention is further optimized as follows:

[0042] The waterborne epoxy curing agent comprises the following preparation steps:

[0043] S1. Polyethylene glycol diglycidyl ether (PEGGE), epoxy resin E51 and propylene glycol methyl ether (PM) were placed in a three-necked flask; heated in an oil bath, the temperature was raised to 80°C, and the pressure in the flask was maintained at 0.1 KPa, and the flask was evacuated for 0.5 to 3 hours and then cooled to room temperature to obtain the treated oligomer;

[0044] S2. Take an aliphatic polyamine, stir and heat to 40-70°C under nitrogen protection, and at this temperature, start dropping the oligomer pre-treated in step S1, and control the addition to be completed within 2 hours; after the addition is completed, keep the reaction warm for a certain time, and after the reaction is completed, distill under reduced pressure until the solvent is completely evaporated to obtain a modified chain extension reaction product;

[0045] S3. Take a sample of the modified chain extension reaction product obtained in step S2 and test it. If the amine value is not significantly reduced, stop the reaction; continue to drop the reactive emulsifier and the end-capping agent at 80°C, and control the addition to be completed within 2 hours. Finally, slowly add an appropriate amount of deionized water, stir for 1 hour, adjust the solid content to 55-60%, and distill under reduced pressure after the reaction is completed. After cooling, filter the material to obtain the water-based epoxy curing agent.

[0046] The waterborne epoxy back surface odorless waterproof coating of the present invention is further optimized as follows:

[0047] It includes one or a combination of the following features:

[0048] The wear-resistant powder is a combination of basalt flakes and glass powder in a weight ratio of 1:2;

[0049] The dispersant is one or a combination of BYK-181, BYK-190, DIS-188A, and SN-5027;

[0050] The defoamer comprises at least one of a polymer composite mineral oil defoamer and an organosilicon defoamer;

[0051] The defoaming agent is one or a combination of BYK-019, BYK-1711, TEGO-901W, FoamStar ST2410AG, BYK-024;

[0052] The thickener is organically modified hectorite clay, with a particle size of 80% ≤ 125 μm, a white powder appearance, low shear viscosity, and can prevent hard precipitation of pigments and fillers, reduce phase separation, and impart reproducible thixotropic fluidity;

[0053] The anti-settling aid is: modified polyurea solution, preferably BYK-420 from BYK Chemical;

[0054] The wetting and leveling agent includes at least one of silicone and acrylic acid;

[0055] The wetting and leveling agent is preferably one or a combination of BYK-346, BYK-333, TEGO-4100, TEGOWET-270, and EFKA-3772;

[0056] The anti-scratch auxiliary agent is one or a combination of DC51, wax emulsion and wax powder; preferably wax emulsion.

[0057] The bactericide is one or a combination of LPC5, LXE, BIOX520W, and BIOXABZ;

[0058] The water-based epoxy emulsion is one or a combination of Dow AEH-20, Dow DER WB3002, and Han Dai HDE8370-WB;

[0059] The preferred water-based epoxy emulsion is mainly a modified epoxy resin, which is used as a bonding component. The epoxy resin is grafted and modified, and a low surface energy polysiloxane is introduced through a silane coupling agent. At the same time, the modified epoxy emulsion obtained by the internal emulsification method increases the contact angle with water, greatly reduces the adhesion of impurities such as dust and bacteria to the coating, and further enhances the wear resistance and scratch resistance of the coating.

[0060] The silane coupling agent is one or a combination of epoxy or diamino-containing silane coupling agents;

[0061] The toughening agent is one or a combination of dipropylene glycol butyl ether, cyclohexane 1,2-diisononyl dicarboxylate, and benzyl alcohol.

[0062] The second object of the present invention is:

[0063] Provided is a method for preparing the aforementioned waterborne epoxy back-water surface odorless waterproof coating, which comprises the following preparation steps:

[0064] S1. Preparation of component A: Add water-based epoxy curing agent to the stirring deionized water in proportion, then add thickener, dispersant, defoamer, anti-scratch agent, bactericide, wetting and leveling agent, and after uniform dispersion, add wear-resistant powder and pigment and filler mixture, grind to appropriate fineness, add the remaining deionized water, stir evenly, add anti-settling agent to adjust the appropriate viscosity, and obtain component A;

[0065] S2. Preparation of component B: Mix the water-based epoxy emulsion, toughening agent and silane coupling agent in proportion to obtain component B;

[0066] S3. Add component B to component A, stir and mix according to proportion, and react to obtain the water-based epoxy back-water surface odorless waterproof coating.

[0067] The third invention object of the present invention is:

[0068] Provided is a coating method for the aforementioned waterborne epoxy back-water surface odorless waterproof coating:

[0069] Use the water-based epoxy back-water surface odorless waterproof coating to directly roll / spray / brush it on the surface of plastic concrete that has not initially set, dry it naturally for one week, and then carry out subsequent conventional treatment.

[0070] The fourth invention objective of the present invention is:

[0071] Provided is a coating, which is obtained by coating the above-mentioned water-based epoxy back-water surface odor-free waterproof coating on a substrate.

[0072] The fifth invention objective of the present invention is:

[0073] Provided is a product comprising a substrate and the above-mentioned coating obtained by coating the substrate, wherein the substrate includes but is not limited to concrete.

[0074] The sixth invention objective of the present invention is:

[0075] Provided is an application of the aforementioned waterborne epoxy back-water surface odorless waterproof coating, characterized in that:

[0076] It includes the following steps:

[0077] A. Base surface treatment: level, dry and clean the base surface to be constructed;

[0078] B. Puttying: Add quartz powder to the water-based epoxy back-water odorless waterproof coating, apply several layers of putty on the base surface, and form a putty layer after curing;

[0079] C. Applying a closed primer: Use the water-based epoxy back-water surface odorless waterproof coating as a closed alkali-resistant primer and apply it on the surface of the putty layer to form a primer layer after curing;

[0080] D. Construction coating: Evenly apply the water-based epoxy back-water surface odorless waterproof coating on the primer layer.

[0081] The waterborne epoxy back surface odorless waterproof coating of the present invention has the following technical characteristics and advantages:

[0082] 1. The water-based epoxy back-water surface odorless waterproof coating of the present invention is different from conventional waterproof coatings. It is specially designed for humid environments and can be applied and cured on wet surfaces. It is easy to construct and can achieve true back-water surface waterproofing. It is not only odorless and environmentally friendly, but also has antibacterial and mildew-proof properties.

[0083] 2. The back surface waterproof effect of the water-based epoxy odorless waterproof coating of the present invention is greatly improved. The epoxy resin and the curing agent are linearly cross-linked and polymerized into a three-dimensional network structure to provide high coating density and high coating hardness; the epoxy group carries ether bonds, hydroxyl groups and other chemical groups to provide high adhesion; the epoxy resin and the toughening agent give the coating excellent toughness, improve the flexibility of the paint film, and make the paint film have more excellent physical and mechanical properties.

[0084] 3. The waterborne epoxy back surface odorless waterproof coating of the present invention adopts modified amine curing agent, and the modified amine curing agent is 100% added to the small molecular amine to ensure that the product has very low vapor pressure and free amine content. The long-chain water-soluble curing agent molecules overlap each other between the nanoparticles to enhance penetration; the ability to cure with water is achieved through penetration-enhanced cross-linking reaction; the molecular design is flexibly used to increase the degree of dispersion, and the nano-scale emulsified particles improve compatibility and form a denser film.

[0085] 4. The water-based epoxy back-water surface odorless waterproof coating of the present invention specifically introduces silane coupling agent and toughening agent in the coating formula to enhance the interface fusion between the coating and the substrate. This combination not only improves the permeability and flexibility of the coating, but also enables the groups in the coating to be closely combined with the substrate or underlying material. Through the synergistic effect with the epoxy resin, a strong chemical bond is formed at the bonding interface, thereby significantly improving the bonding strength.

[0086] At the same time, silane can react chemically with moisture on the surface of the substrate or moisture in the air to form a water-repellent treatment layer, which can effectively inhibit the entry of moisture and provide additional waterproof protection for the substrate. Through this innovative formula design, the product of the present invention not only has strong adhesion, but also has excellent waterproof performance.

[0087] 5. The water-based epoxy back-water surface odorless waterproof coating of the present invention is a water-based coating product with significant environmental protection characteristics. Its VOC content is greatly reduced, thereby reducing the impact on human health and the environment.

[0088] The product of the present invention is highly safe and environmentally friendly and is suitable for various environments, including home decoration and industrial coating protection, making it an ideal multifunctional coating solution.

[0089] In addition, energy savings are achieved during the production process. DETAILED DESCRIPTION

[0090] In order to make the application, technical scheme and advantages of the present invention more clear, the present invention is described in detail in conjunction with specific embodiments. It should be understood that the embodiments are only used to illustrate the present invention, but not to limit the protection scope of the present invention. All simple improvements to the preparation method of the present invention under the premise of the concept of the present invention belong to the protection scope of the present invention.

[0091] The following are the raw materials that can be used in the technical scheme and embodiments of the present invention, as shown in Table 1.

[0092] Table 1

[0093]

[0094]

[0095] Example 1

[0096] A method for preparing a waterborne epoxy back-water surface odorless waterproof coating, comprising the following preparation steps:

[0097] S1. Preparation of component A: Add water-based epoxy curing agent to the stirring deionized water in proportion, then add thickener, dispersant, defoamer, anti-scratch agent, bactericide, wetting and leveling agent, and after uniform dispersion, add wear-resistant powder and pigment and filler mixture, grind to appropriate fineness, add the remaining deionized water, stir evenly, add anti-settling agent to adjust the appropriate viscosity, and obtain component A;

[0098] S2. Preparation of component B: Mix the water-based epoxy emulsion, toughening agent and silane coupling agent in proportion to obtain component B;

[0099] S3. Add component B to component A, stir and mix according to proportion, and react to obtain the water-based epoxy back-water surface odorless waterproof coating.

[0100] in:

[0101] The waterborne epoxy curing agent is a modified amine curing agent, which includes:

[0102] Epoxy resin E51, polyethylene glycol diglycidyl ether, aliphatic polyamine, reactive emulsifier, capping agent and propylene glycol methyl ether (PM);

[0103] The weight ratio of the epoxy resin E51: polyethylene glycol diglycidyl ether (PEGGE): aliphatic polyamine is 1:4:10;

[0104] The amount of the reactive emulsifier is 1.56% by weight of the aliphatic polyamine;

[0105] The amount of the end-capping agent is 5% by weight of the aliphatic polyamine;

[0106] The amount of propylene glycol methyl ether (PM) is 5% by weight of the epoxy resin E51;

[0107] The reactive emulsifier includes sodium acrylamide isopropyl sulfonate and fatty alcohol polyoxyethylene ether;

[0108] The weight ratio of sodium acrylamidoisopropyl sulfonate to fatty alcohol polyoxyethylene ether is 3:7;

[0109] The end-capping agent includes: o-toluene glycidyl ether (CGE) and C12-14 alkyl glycidyl ether (AGE);

[0110] The weight ratio of o-cresol glycidyl ether (CGE) to C12-14 alkyl glycidyl ether (AGE) is 2:1;

[0111] The waterborne epoxy curing agent comprises the following preparation steps:

[0112] S1. 80.8 g of a mixture of polyethylene glycol diglycidyl ether (PEGGE), epoxy resin E51 and propylene glycol methyl ether (PM) was placed in a three-necked flask; heated in an oil bath, the temperature was raised to 80 ° C, and the pressure in the flask was maintained at 0.1 KPa, and the evacuation was performed for 0.5 to 3 hours, and then the temperature was lowered to room temperature to obtain the treated oligomer;

[0113] S2. Take 160g of aliphatic polyamine (ethylenediamine: hexamethylenediamine: diethylenetriamine weight ratio = 5:2:3), stir and heat to 40-70°C under nitrogen protection, and start to dropwise add the oligomer pre-treated in step S1 at this temperature, and control the addition to be completed within 2 hours; after the addition is completed, keep the reaction warm for a certain time, and after the reaction is completed, distill under reduced pressure until the solvent is completely evaporated to obtain a modified chain extension reaction product;

[0114] S3. Take a sample of the modified chain extension reaction product obtained in step S2 and test it. If the amine value is not significantly reduced, stop the reaction; at 80°C, continue to drop 2.5g of reactive emulsifier and 8g of end-capping agent, and control the addition to be completed within 2 hours. Finally, slowly add an appropriate amount of deionized water, stir for 1h, adjust the solid content to 55-60%, and distill under reduced pressure after the reaction is completed. After cooling, filter the material to obtain the water-based epoxy curing agent.

[0115] The preparation of the pigment and filler polymer slurry comprises the following steps:

[0116] Titanium dioxide, quartz powder, dispersant and silane coupling agent were charged into a closed ball mill reactor in proportion and ball milled for 16 hours to prepare a pigment filler polymer slurry in a white sludge state with a particle size of 40 to 80 nm.

[0117] The pigment and filler mixture includes: titanium dioxide R996, quartz powder 706, dispersant BYK-190 and silane coupling agent 0FS-6020, and the weight ratio of titanium dioxide: quartz powder: dispersant: silane coupling agent is 2:1:0.5:0.1.

[0118] The preparation methods of Examples 2 and 3 are the same as those of Example 1, with the main difference being that the composition and amount of some raw materials are different.

[0119] The composition and preparation method of Comparative Example 1 are basically the same as those of Example 1, the main difference being that Comparative Example 1 uses a conventional water-based epoxy curing agent instead of the modified epoxy curing agent used in Example 1.

[0120] The composition and preparation method of Comparative Example 2 are basically the same as those of Example 2. The main difference is that Comparative Example 2 uses conventional pigments and fillers, titanium dioxide and quartz powder, to replace the pigment and filler mixture used in Example 1.

[0121] The composition and preparation method of Comparative Example 3 are basically the same as those of Example 3, the main difference being that the wear-resistant powder used in Example 3 is replaced by ordinary wear-resistant powder.

[0122] Table 2 Specific composition of raw materials in the examples (weight percentage %)

[0123]

[0124]

[0125] The products obtained in the embodiments and comparative examples were tested for wear resistance and pencil hardness according to JC / T 2217-2014 (2017) "Epoxy Resin Waterproof Coating" and the technical requirements of type S in GB / T 22374-2018 floor coating materials; the odor level and odor dissipation time were tested according to Q / LBZS 09-2021 net odor interior wall latex paint (low odor interior wall latex paint). The test results are shown in Table 5.

[0126] Among them, Q / LBZS 09-2021 odorless interior latex paint (low odor interior latex paint) tests the odor level and odor dissipation time; the technical requirements are as follows:

[0127] 1) The physical properties of the odorless products meet the requirements of GB / T9756-2018 for corresponding products;

[0128] 2) The limit values ​​of harmful substances in odorless products should comply with the requirements for interior wall coatings in Table 1 of GB18582-2020;

[0129] 3) The odor evaluation performance requirements of pure latex paint (low odor latex paint) shall comply with the requirements of Table 3;

[0130] Table 3 Odor requirements

[0131] project Require Odor level, level ≤ 2 Odor dissipation time, hr≤ 8

[0132] Odor dissipation time test method: paint the test sample on the substrate and place it in a glass / stainless steel odor test chamber with a length of 0.5m, a width of 0.4m and a height of 0.5m. With the test chamber door, odor evaluation chamber door and ventilation valve all open, force ventilation with a fan for 10 minutes, then close all the doors and seal the odor test chamber for 45 minutes. Open the odor test chamber door, and the odor test team will evaluate the odor within 5 minutes. Perform odor comparison every 1 hour, and the odor level evaluation is shown in Table 4.

[0133] Table 4 Odor levels

[0134] Grade Level Status description Level 1 Odorless, undetectable Level 2 Slight odor but noticeable Level 3 There is an odor, but it is not strongly unpleasant Level 4 Strong unpleasant odor Level 5 Has a pungent, unpleasant odor

[0135] Table 5 Comparison of the results of the embodiments and comparative examples

[0136]

[0137]

[0138] Based on the above results, comparative analysis:

[0139] The performance of the waterborne epoxy back-water surface odorless waterproof coating prepared in the embodiments of the present invention far exceeds the national standards, among which implementation 3 has the best performance.

[0140] 1. It can be seen from Examples 1 to 3 that the water-based epoxy back-water surface odor-free waterproof coating prepared by the present invention is practical and effective, has good coating anti-seepage pressure, and the performance is better than that of Comparative Examples 1 to 3. It can achieve good water-facing and back-water surface coating anti-seepage pressure, and the back-water surface coating anti-seepage pressure is greater than 1.0 MPa. At the same time, the odor level can reach the odor-free level, no free formaldehyde and benzene series are detected, and the environmental protection performance is excellent. It is a true water-based epoxy back-water surface odor-free waterproof coating.

[0141] 2. Example 3 adjusts the dosage of the modified amine curing agent on the basis of Example 1 and Example 2, optimizes and adjusts the optimal reaction ratio of the epoxy resin and the modified amine curing agent, and finds a better addition ratio of the toughening agent and the silane coupling agent to enhance the interface fusion between the coating and the substrate, and significantly improves the pencil hardness, wear resistance, dry, wet, immersion, heat treatment bonding strength and other properties; the modified amine curing agent prepared in the present invention can effectively balance rigidity and flexibility, can be linearly cross-linked with the epoxy resin, and polymerized into a three-dimensional network structure, and the wear resistance and pencil hardness are better than those of Comparative Examples 1 to 3.

[0142] 3. In Comparative Example 2, only conventional pigments and fillers, titanium dioxide and quartz powder, are used, and the effect of the modified pigment and filler mixture used in Example 2 cannot be achieved. The system has a high porosity, and its hardness and impermeability are significantly lower than those in Example 2; In Comparative Example 3, only conventional wear-resistant powder is used, and the density of the coating is significantly reduced, the material bonding performance is poor, and the filling effect of capillary pores is poor, resulting in a decrease in various properties, thereby affecting the mechanical properties of the coating. The wear resistance, pencil hardness, impermeability pressure of the water-facing surface and the back water surface are significantly lower than those in Example 3.

[0143] The water-based epoxy back-water surface odorless waterproof coating prepared by the present invention pre-treats the pigments and fillers, which can effectively improve the dispersion of the fillers and the density of the coating compared with conventional dispersed pigments and fillers; in addition, high-hardness wear-resistant powder basalt flakes and glass powder are used to fill the pores of the coating film to form an effective water-repellent layer, thereby extending the service life of the coating.

[0144] 4. The water-based epoxy back-water surface odorless waterproof coating of the present invention specially introduces silane coupling agent and toughening agent in the coating formula to enhance the interface fusion between the coating and the substrate, and significantly improves the dry, wet, immersion and heat treatment bonding strength.

[0145] 5. The coating prepared by the present invention has excellent hardness, lower VOC content, better drying speed and composite coating film performance, excellent comprehensive performance, and can be adapted to different use areas such as home decoration, industry, and roofs.

[0146] To sum up, the above are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the present invention using the disclosed technical content are regarded as equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

[0147] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0148] The experimental methods without specific conditions in the present invention are usually carried out under conventional conditions or conditions recommended by the manufacturer.

[0149] Unless otherwise stated, the various optimization technical solutions in the present invention can be combined with each other.

[0150] Unless otherwise indicated, percentages and parts are by weight.

[0151] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any method and material similar or equivalent to the described content can be applied to the method of the present invention.

Claims

1. A water-based epoxy back-water surface odorless waterproof coating, characterized in that: It comprises component A and component B, and the weight ratio of component A to component B is 1 to 5:1; The A component comprises the following raw materials in percentage by weight: Water-based epoxy curing agent 20-50%, dispersant 0.5-2%, defoamer 0.1-2%, thickener 0.1-2%, wear-resistant powder 10-20%, pigment and filler mixture 10-40%, water 10-40%, anti-settling agent 0.01-2%, wetting and leveling agent 0.01-2%, anti-scratch agent 0.01-2%, bactericide 0.01-2%, all components are prepared to 100%; The waterborne epoxy curing agent is a modified amine curing agent, which includes: Epoxy resin E51, polyethylene glycol diglycidyl ether, aliphatic polyamine, reactive emulsifier, capping agent and propylene glycol methyl ether; The weight ratio of the epoxy resin E51: polyethylene glycol diglycidyl ether: aliphatic polyamine is 1-3:2-4:10-15; The amount of the reactive emulsifier is 0.5-2% by weight of the aliphatic polyamine; The amount of the end-capping agent is 1 to 10% by weight of the aliphatic polyamine; The amount of propylene glycol methyl ether is 5-12% of the weight of epoxy resin E51; The reactive emulsifier includes sodium acrylamide isopropyl sulfonate and fatty alcohol polyoxyethylene ether; The weight ratio of sodium acrylamidoisopropyl sulfonate to fatty alcohol polyoxyethylene ether is 1-5:1-10; The end-capping agent includes: o-toluene glycidyl ether and C12-14 alkyl glycidyl ether; The weight ratio of o-toluene glycidyl ether to C12-14 alkyl glycidyl ether is 1-5:1-10; The aliphatic polyamine is one or a combination of ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, and diethylaminopropylamine; The wear-resistant powder is one or a combination of basalt flakes, glass powder, and barium sulfate; The pigment and filler mixture comprises: titanium dioxide, quartz powder, dispersant and silane coupling agent, and the weight ratio of titanium dioxide: quartz powder: dispersant: silane coupling agent is 1-2: 1-2: 0.5: 0.1-0.5; The titanium dioxide is a titanium dioxide with aluminum oxide or chromium oxide coated on the surface, wherein the weight percentage of titanium dioxide is 94-95.5%, the oil absorption is 17-20g / 100g, and the whiteness is ≥93%; The quartz powder is quartz powder with SiO2 content ≥ 99%; The pigment-filler mixture is mixed and preformed into a pigment-filler polymer slurry before use; The B component comprises the following raw materials in percentage by weight: The aqueous epoxy emulsion is 20-90%, the silane coupling agent is 1-10%, the toughening agent is 1-20%, and all the components are prepared to be 100%.

2. The waterborne epoxy back surface odorless waterproof coating according to claim 1, characterized in that: The preparation of the pigment and filler polymer slurry comprises the following steps: Titanium dioxide, quartz powder, dispersant and silane coupling agent were charged into a closed ball mill reactor in proportion and ball milled for 16 hours to prepare a pigment filler polymer slurry in a white sludge state with a particle size of 40 to 80 nm.

3. The waterborne epoxy back surface odorless waterproof coating according to claim 1, characterized in that: The glass powder is one or a combination of metal oxides: spherical powders made of silicon oxide, aluminum oxide, iron oxide and sodium oxide.

4. The waterborne epoxy back surface odorless waterproof coating according to claim 1, characterized in that: The waterborne epoxy curing agent comprises the following preparation steps: S1. Polyethylene glycol diglycidyl ether, epoxy resin E51 and propylene glycol methyl ether were placed in a three-necked flask; heated in an oil bath, heated to 80 ° C, and then the pressure in the flask was maintained at 0.1 KPa, and the evacuation was performed for 0.5 to 3 hours and then cooled to room temperature to obtain the treated oligomer; S2. Take an aliphatic polyamine, stir and heat to 40-70°C under nitrogen protection, and at this temperature, start dropping the oligomer pre-treated in step S1, and control the addition to be completed within 2 hours; after the addition is completed, keep the reaction warm for a certain time, and after the reaction is completed, distill under reduced pressure until the solvent is completely evaporated to obtain a modified chain extension reaction product; S3. Take a sample of the modified chain extension reaction product obtained in step S2 and test it. If the amine value is not significantly reduced, stop the reaction; continue to drop the reactive emulsifier and the end-capping agent at 80°C, and control the addition to be completed within 2 hours. Finally, slowly add an appropriate amount of deionized water, stir for 1 hour, adjust the solid content to 55-60%, and distill under reduced pressure after the reaction is completed. After cooling, filter the material to obtain the water-based epoxy curing agent.

5. The waterborne epoxy back surface odorless waterproof coating according to claim 1, characterized in that: It includes one or a combination of the following features: The wear-resistant powder is a combination of basalt flakes and glass powder in a weight ratio of 1:2; The dispersant is one or a combination of BYK-181, BYK-190, DIS-188A, and SN-5027; The defoaming agent is one or a combination of BYK-019, BYK-1711, TEGO-901W, FoamStar ST2410AG, BYK-024; The thickener is organic modified hectorite clay, with a particle size of 80% ≤ 125 μm and an appearance of white powder; The anti-settling aid is: modified polyurea solution; The wetting and leveling agent is one or a combination of BYK-346, BYK-333, TEGO-4100, TEGOWET-270, and EFKA-3772; The anti-scratch additive is one or a combination of DC51, wax emulsion and wax powder; The bactericide is one or a combination of LPC5, LXE, BIOX520W, and BIOXABZ; The water-based epoxy emulsion is one or a combination of Dow AEH-20, Dow DER WB3002, and Han Dai HDE8370-WB; The silane coupling agent is one or a combination of epoxy or diamino-containing silane coupling agents; The toughening agent is one or a combination of dipropylene glycol butyl ether, cyclohexane 1,2-diisononyl dicarboxylate, and benzyl alcohol.

6. A method for preparing the waterborne epoxy back-water surface odorless waterproof coating according to claim 1, characterized in that: It comprises the following preparation steps: S1. Preparation of component A: Add water-based epoxy curing agent to the stirring deionized water in proportion, then add thickener, dispersant, defoamer, anti-scratch agent, bactericide, wetting and leveling agent, and after uniform dispersion, add wear-resistant powder and pigment and filler mixture, grind to appropriate fineness, add the remaining deionized water, stir evenly, add anti-settling agent to adjust the appropriate viscosity, and obtain component A; S2. Preparation of component B: Mix the water-based epoxy emulsion, toughening agent and silane coupling agent in proportion to obtain component B; S3. Add component B to component A, stir and mix according to proportion, and react to obtain the water-based epoxy back-water surface odorless waterproof coating.

7. A coating method for the waterborne epoxy back-water surface odorless waterproof coating according to claim 1, characterized in that: Use the water-based epoxy back-water surface odorless waterproof coating to directly roll / spray / brush on the surface of plastic concrete that has not initially set, dry naturally for one week, and then carry out subsequent conventional treatment.

8. A coating, characterized in that: The coating is obtained by coating the water-based epoxy back-water surface odor-free waterproof coating as claimed in claim 1 on a substrate.

9. A product, characterized in that: The invention comprises a substrate and the coating according to claim 8 coated on the substrate.

10. An application of the waterborne epoxy odorless waterproof coating for back water surface according to claim 1, characterized in that: It includes the following steps: A. Base surface treatment: level, dry and clean the base surface to be constructed; B. Puttying: Add quartz powder to the water-based epoxy back-water odorless waterproof coating, apply several layers of putty on the base surface, and form a putty layer after curing; C. Applying a closed primer: Use the water-based epoxy back-water surface odorless waterproof coating as a closed alkali-resistant primer and apply it on the surface of the putty layer to form a primer layer after curing; D. Construction coating: Evenly apply the water-based epoxy back-water surface odorless waterproof coating on the primer layer.

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