Breathable epoxy seal primer for concrete and preparation method thereof

Abstract

According to the breathable epoxy seal primer for the concrete and the preparation method of the breathable epoxy seal primer, aliphatic polyether modified epoxy resin and hyperbranched epoxy toughened resin CYH-277 in the breathable epoxy seal primer for the concrete are combined with a modified amine curing agent to form a multi-branched bridging type net structure; a filler with a micro-nano porous structure is embedded into the multi-branched bridging type net structure to form the epoxy seal primer with high air permeability, and the outer surface of the primer has certain hydrophobicity, so that external water can be prevented from entering a paint film to cause damage to concrete. Meanwhile, the breathable epoxy seal primer for the concrete has waterproofness, excellent flexibility, higher tensile strength, good corrosion resistance and strong adhesive force, and can better protect the concrete from cracking and corrosion.

Description

Technical Field

[0001] The invention relates to the technical field of epoxy coatings, and in particular to a breathable epoxy sealing primer for concrete and a preparation method thereof. Background Art

[0002] Concrete structures are widely used in various fields such as water conservancy projects, road construction, and bridge construction. However, concrete structures are porous structures, moisture can easily enter their interior, and alkali can easily seep out. When the temperature difference is large, it is easy to cause concrete cracking. Currently, epoxy sealing primer is commonly applied to concrete structures to strengthen the surface strength of the concrete base, resist the back pressure caused by the entry of water vapor, improve the concrete's resistance to alkali and salt precipitation, and provide surface decorative protection to extend the service life.

[0003] However, the main problems currently existing in most concrete epoxy sealing primers are: conventional epoxy sealing primers are not flexible enough, resulting in poor elongation at break, and the coating film will crack as the concrete structure expands and contracts, causing moisture, sand, etc. in the environment to enter the concrete structure through the cracks, causing further damage; conventional epoxy sealing primers have poor air permeability. When the concrete surface is coated with sealing primer, the air, water vapor and other gases in the concrete voids are squeezed or affected by high temperature and break through the paint film outward, resulting in crater-shaped holes, pinholes, peaks and other phenomena in the paint film, with poor sealing effect, requiring secondary grinding and repair.

[0004] Therefore, a breathable and flexible epoxy sealing primer is needed to protect the concrete surface. It can allow the gas inside the concrete to pass through the paint film without causing damage to the paint film, and can also effectively prevent problems such as paint film cracking, water seepage, and powdering caused by concrete cracking, greatly extending the service life of the concrete. Summary of the invention

[0005] The object of the present invention is to provide a breathable epoxy sealing primer for concrete and a preparation method thereof, so as to solve the technical problems of insufficient flexibility and poor air permeability of the existing conventional epoxy sealing primer.

[0006] In order to solve the above technical problems, the present invention firstly provides a breathable epoxy sealing primer for concrete, comprising component A and component B, wherein component A comprises, by mass: 10 to 25 parts of small molecule epoxy resin, 8 to 15 parts of aliphatic polyether modified epoxy resin, 5 to 15 parts of hyperbranched epoxy toughening resin, 1 to 3 parts of dispersant, 1 to 2 parts of surface additive, 2 to 8 parts of polyamide wax, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of diatomaceous earth, 5 to 15 parts of porous alumina, 10 to 50 parts of talc, 5 to 10 parts of zirconium phosphate and 5 to 10 parts of nano titanium dioxide; Component B includes, by mass, 20 to 40 parts of a modified amine curing agent, 1 to 3 parts of the dispersant, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of porous alumina, 2 to 10 parts of zirconium phosphate, 30 to 60 parts of talc and 5 to 10 parts of nano titanium dioxide.

[0007] Preferably, the mass ratio of component A to component B is (1.5-2):1.

[0008] Preferably, the small molecule epoxy resin is epoxy resin E51; the aliphatic polyether modified epoxy resin is prepared by reacting and modifying the small molecule epoxy resin with aliphatic difunctional glycidyl ether.

[0009] Preferably, the aliphatic difunctional glycidyl ether is at least one of 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether and neopentyl glycol diglycidyl ether.

[0010] Preferably, the hyperbranched epoxy toughening resin is alicyclic polymer CYH-277, the dispersant is high molecular polymer dispersant H-3110, and the model of the polyamide wax is DeuRheo 229 or CANFAIR229.

[0011] Preferably, the surface additive is polydimethylsiloxane WE-D9000.

[0012] Preferably, the modified amine curing agent is cardanol-modified phenolic amine curing agent CARLOS-2213, and the active hydrogen equivalent weight AHEW is 90-100.

[0013] Preferably, the particle size of talc is 400-1250 mesh.

[0014] Accordingly, the present invention also provides a method for preparing the breathable epoxy sealing primer for concrete as described above, the method comprising the following steps: S10, according to the formula mass ratio, 10 to 25 parts of small molecule epoxy resin, 8 to 15 parts of aliphatic polyether modified epoxy resin, 5 to 15 parts of hyperbranched epoxy toughening resin, 1 to 3 parts of dispersant and 2 to 8 parts of polyamide wax are mixed and dispersed, and during the dispersion process, 1 to 2 parts of surface additive, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of diatomaceous earth, 5 to 15 parts of porous alumina, 10 to 50 parts of talc, 5 to 10 parts of zirconium phosphate and 5 to 10 parts of nano titanium dioxide are slowly added to obtain component A; S20, according to the formula mass ratio, 20 to 40 parts of modified amine curing agent and 1 to 3 parts of dispersant are mixed and dispersed, and during the dispersion process, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of porous alumina, 2 to 10 parts of zirconium phosphate, 30 to 60 parts of talc and 5 to 10 parts of nano titanium dioxide are slowly added to obtain component B; S30, mixing component A and component B in a mass ratio of (1.5-2):1 to obtain a breathable epoxy sealing primer for concrete.

[0015] Preferably, in step S10, the preparation process of the aliphatic polyether-modified epoxy resin is as follows: Add epoxy resin E51, bisphenol A, aliphatic difunctional glycidyl ether and xylene into a reaction bottle, heat to 125°C, and add catalyst triphenylphosphonium iodide; After that, the temperature is raised to 150° C. for half an hour and kept for 2 to 4 hours. When the epoxy value reaches 0.30 to 0.33 mol / 100 g, the temperature is lowered to 80° C. and subjected to rotary evaporation to obtain the solvent-free aliphatic polyether modified epoxy resin.

[0016] The beneficial effects of the present invention are as follows: Different from the prior art, the present invention provides a breathable epoxy sealing primer for concrete and a preparation method thereof, wherein the aliphatic polyether modified epoxy resin and the hyperbranched epoxy toughening resin in the breathable epoxy sealing primer for concrete form a multi-branched bridge-type network structure under the combination of a modified amine curing agent, and the small molecule epoxy resin plays an auxiliary role in the staggered combination of long and short chains between the two, and a hole network structure is formed by the mutual crossing between the resins. The hole network structure is simultaneously embedded with a porous filler with a micro-nano porous structure to form a highly permeable epoxy sealing primer, and the outer surface of the primer also has a certain hydrophobicity, which can prevent external water from entering the interior of the paint film and causing damage to the concrete. At the same time, the above-mentioned breathable epoxy sealing primer for concrete can effectively improve the smoothness and integrity of the paint film when the gas in the internal voids of the concrete is squeezed out after the sealing paint is applied, and the gas remaining in the voids after curing can also freely overflow through the microporous structure inside the paint film, and the paint film is waterproof, which can prevent external moisture from returning to the inside of the paint film. At the same time, it also has excellent flexibility, higher tensile strength, good corrosion resistance, and strong adhesion, which can better protect the concrete from cracking and corrosion. Further, the above-mentioned breathable epoxy sealing primer for concrete can also play a role in replacing two-component epoxy putty, reducing the coating process in multiple systems and saving coating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention provides a flow chart of a method for preparing a breathable epoxy sealing primer for concrete according to an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] In order to achieve the above technical objectives, this application adopts the following technical solutions: In a first aspect, the present invention first provides a breathable epoxy sealing primer for concrete, comprising component A and component B, wherein component A comprises, by mass: 10 to 25 parts of a small molecule epoxy resin, 8 to 15 parts of an aliphatic polyether-modified epoxy resin, 5 to 15 parts of a hyperbranched epoxy toughening resin, 1 to 3 parts of a dispersant, 1 to 2 parts of a surface additive, 2 to 8 parts of a polyamide wax, 0.5 to 1 part of an organic modified bentonite, 5 to 15 parts of diatomaceous earth, 5 to 15 parts of porous alumina, 10 to 50 parts of talc, 5 to 10 parts of zirconium phosphate and 5 to 10 parts of nano titanium dioxide; Component B includes, by mass, 20 to 40 parts of a modified amine curing agent, 1 to 3 parts of the dispersant, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of porous alumina, 2 to 10 parts of zirconium phosphate, 30 to 60 parts of talc and 5 to 10 parts of nano titanium dioxide.

[0020] In the embodiment of the present invention, the resin system in component A includes a small molecule epoxy resin, an aliphatic polyether modified epoxy resin and a hyperbranched epoxy toughening resin CYH-277.

[0021] Aliphatic polyether modified epoxy resin is a reaction modification of epoxy resin E51 by specific aliphatic difunctional glycidyl ether to provide epoxy resin with extremely strong toughening performance; the introduction of aliphatic chain segments can improve the flexibility and weather resistance of the resin, making it more suitable for concrete surfaces and reducing the cracking of primers caused by changes in the expansion and contraction of the concrete base. Hyperbranched epoxy toughening resin CYH-277 further enhances the toughness of the primer, improves the adaptability of the coating to tiny cracks or unevenness on the concrete surface, and enhances the adhesion of the coating to the base. At the same time, the small molecule epoxy resin plays an auxiliary role in the staggered combination of long and short chains between the two, using the hole network structure formed by the cross-linking of the resins.

[0022] Specifically, the aliphatic polyether modified epoxy resin is prepared by reacting and modifying a small molecule epoxy resin with aliphatic difunctional glycidyl ether; the small molecule epoxy resin is epoxy resin E51, and the hyperbranched epoxy toughening resin is a hyperbranched epoxy toughening resin CYH-277 of alicyclic polymer. Among them, the hyperbranched epoxy toughening resin CYH-277 has a hyperbranched structure, a dendrite-type low-viscosity polymer with multiple active end groups, which can better reduce the viscosity of the system and has better wettability for fillers with microporous structures. There are a large number of void structures inside its molecules, which can cause a large amount of shear deformation of the epoxy cured product, further increasing the flexibility and crack resistance of the paint film and other mechanical properties.

[0023] Preferably, the aliphatic difunctional glycidyl ether is at least one of 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether and neopentyl glycol diglycidyl ether.

[0024] Preferably, the dispersant is a high molecular polymer dispersant H-3110, the model of the polyamide wax is DeuRheo 229 or CANFAIR229, and the surface additive is polydimethylsiloxane WE-D9000.

[0025] Specifically, the dispersant H-3110 in component A can evenly disperse the solid particles such as pigments and fillers in the system, prevent agglomeration, and ensure that the components of the primer are evenly mixed, thereby ensuring the consistency of the coating performance. Polyamide wax DeuRheo229 or CANFAIR 229 can improve the rheological properties of the primer, such as anti-settling and thixotropy, so that the primer is not easy to settle and stratify during storage. During construction, the viscosity can be adjusted according to the needs of operations such as brushing or spraying to ensure smooth construction. The surface additive polydimethylsiloxane WE-D9000 reduces surface tension, helps the primer to wet and spread on the concrete surface, and makes the coating smoother. At the same time, it may also have a certain defoaming effect, reduce the generation of bubbles during construction, and improve the density of the coating. Organic modified bentonite can cooperate with other additives to further stabilize the rheological properties of the system and prevent solid particles from settling.

[0026] In the embodiment of the present invention, the first porous filler in component A comprises, by mass, 5 to 15 parts of diatomaceous earth, 5 to 15 parts of porous alumina, 10 to 50 parts of talc, 5 to 10 parts of zirconium phosphate and 5 to 10 parts of nano titanium dioxide.

[0027] Specifically, the porous fillers such as diatomaceous earth, porous alumina, talcum powder, zirconium phosphate and nano titanium dioxide in the first porous filler have multiple functions. On the one hand, they can fill the primer system, increase the volume of the primer and reduce the cost; on the other hand, the porous structure helps the air permeability of the primer, so that the water vapor inside the concrete can be slowly dissipated, avoiding the accumulation of water vapor between the coating and the base layer, resulting in blistering and peeling of the coating, and at the same time, it can also improve the mechanical properties of the primer such as hardness and wear resistance. Different fillers work together to play their respective advantages; at the same time, nano titanium dioxide provides certain antibacterial and anti-aging properties.

[0028] In the embodiment of the present invention, the modified amine curing agent in component B is a cardanol-modified phenolic amine curing agent CARLOS-2213, whose active hydrogen equivalent AHEW is 90-100; wherein, the cardanol-modified phenolic amine curing agent CARLOS-2213 can undergo a cross-linking curing reaction with the aliphatic polyether-modified epoxy resin in component A under certain conditions due to its suitable active hydrogen equivalent, forming a coating with good mechanical properties, chemical stability and corrosion resistance. The mass ratio of the cardanol-modified phenolic amine curing agent to component A is optimized to ensure that the curing reaction is fully carried out so that the coating can achieve the expected performance indicators, such as hardness, adhesion, water resistance, etc.

[0029] In the embodiment of the present invention, the second porous filler in component B comprises, by mass, 5 to 15 parts of porous alumina, 2 to 10 parts of zirconium phosphate, 30 to 60 parts of talc powder and 5 to 10 parts of nano titanium dioxide.

[0030] Specifically, the dispersant H-3110 and organic modified bentonite in component B have similar functions to those in component A, mainly to ensure that the curing agent and filler are evenly mixed and stabilize the system performance. The porous alumina, zirconium phosphate, talcum powder and nano-titanium dioxide in the second porous filler further enhance the hardness, wear resistance and air permeability of the coating, and together with the first porous filler in component A, construct a primer coating structure with good comprehensive performance.

[0031] Furthermore, the particle size of the talc is 400-1250 mesh.

[0032] Accordingly, see Figure 1 The present invention also provides a method for preparing the breathable epoxy sealing primer for concrete as described above, the method comprising the following steps: S10, according to the formula mass ratio, 10 to 25 parts of small molecule epoxy resin, 8 to 15 parts of aliphatic polyether modified epoxy resin, 5 to 15 parts of hyperbranched epoxy toughening resin, 1 to 3 parts of dispersant and 2 to 8 parts of polyamide wax are mixed and dispersed, and during the dispersion process, 1 to 2 parts of surface additive, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of diatomaceous earth, 5 to 15 parts of porous alumina, 10 to 50 parts of talc, 5 to 10 parts of zirconium phosphate and 5 to 10 parts of nano titanium dioxide are slowly added to obtain the A component.

[0033] Specifically, firstly, small molecule epoxy resin, aliphatic polyether modified epoxy resin, hyperbranched epoxy toughening resin CYH-277, dispersant and polyamide wax are mixed and dispersed. This step is to fully mix the resin and some key additives to form a preliminary stable system core. Because the interaction of these components is crucial to the performance basis of the entire primer, such as the compatibility between resins, the dispersing effect of dispersants on resins and subsequent fillers, and the preliminary adjustment of the rheological properties of the system by polyamide wax. Then slowly add surface additives, organic modified bentonite and the first porous filler to continue dispersing. The surface additive is added last because it mainly acts on the surface of the system, and premature addition may affect its distribution effect on the surface. The first porous filler is added last and slowly to avoid uneven dispersion caused by a large amount of one-time addition, to ensure that the first porous filler can be evenly dispersed in the resin system that has been preliminarily mixed, and finally obtain a uniform and stable A component.

[0034] S20, according to the formula mass ratio, 20 to 40 parts of modified amine curing agent and 1 to 3 parts of dispersant are mixed and dispersed, and during the dispersion process, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of porous alumina, 2 to 10 parts of zirconium phosphate, 30 to 60 parts of talc and 5 to 10 parts of nano titanium dioxide are slowly added to obtain component B.

[0035] Specifically, the modified amine curing agent and the dispersant are first mixed and dispersed to ensure that the curing agent and the dispersant are fully and evenly mixed to ensure the dispersibility of the curing agent in the system so that it can evenly participate in the curing reaction when subsequently mixed with component A. Then, the organic modified bentonite and the second porous filler are slowly added and continued to disperse to obtain a uniform component B.

[0036] S30, uniformly mixing component A and component B in a mass ratio of (1.5-2):1 to obtain a breathable epoxy sealing primer for concrete.

[0037] Specifically, the process of mixing component A and component B evenly in a specific mass ratio is a key step in initiating the curing reaction. During the mixing process, the uniformity of the mixing must be ensured, because uneven mixing may lead to incomplete or over-curing of some parts, affecting the overall performance of the coating. For example, uneven hardness may lead to uneven coating surface, and uneven adhesion may cause local peeling of the coating.

[0038] Further, in step S10, the preparation process of the aliphatic polyether modified epoxy resin is as follows: Add epoxy resin E51, bisphenol A, aliphatic difunctional glycidyl ether and xylene into a reaction bottle, heat to 125°C, and add catalyst triphenylphosphonium iodide; After that, the temperature is raised to 150° C. for half an hour and kept for 2 to 4 hours. When the epoxy value reaches 0.30 to 0.33 mol / 100 g, the temperature is lowered to 80° C. and rotary evaporation is performed to obtain a solvent-free aliphatic polyether modified epoxy resin.

[0039] In the preparation process of the above-mentioned aliphatic polyether modified epoxy resin, epoxy resin E51, bisphenol A, aliphatic difunctional glycidyl ether and xylene are added to the reaction bottle, the temperature is raised and the catalyst triphenylphosphonium iodide is added to start the reaction. Xylene is used as a solvent to provide a medium environment for the reaction so that the reactants can be fully mixed and contacted. The catalyst triphenylphosphonium iodide accelerates the reaction process. After reacting at 125°C for half an hour, the temperature is continued to rise to 150°C for insulation reaction for 2 to 4 hours. The epoxy value is accurately controlled to reach 0.30 to 0.33 mol / 100g by controlling the reaction time and temperature. This epoxy value range is the key to ensuring that the modified epoxy resin has suitable reaction activity and performance. Finally, the temperature is lowered to 80°C for rotary evaporation to remove the solvent xylene to obtain a solvent-free aliphatic polyether modified epoxy resin. The solvent-free system is conducive to reducing the emission of volatiles in the primer during the curing process and improving environmental protection. At the same time, it also makes the solid content of the primer higher, and the coating thickness and performance are easier to control.

[0040] The technical solution of the present invention is now further described in conjunction with specific embodiments.

[0041] Example 1 (in component A, the hyperbranched epoxy toughening resin CYH-277 accounts for 25% of the total resin mass fraction): This embodiment 1 provides a breathable epoxy sealing primer for concrete, including component A and component B. Component A and component B are evenly mixed in a ratio of 2:1 to obtain the breathable epoxy sealing primer.

[0042] Specifically, component A includes, by mass: 15 parts of epoxy resin E-51 (Baling Petrochemical CYD-128), 12 parts of aliphatic polyether modified epoxy resin, 9 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110 (produced by Huihang Trading, with obvious viscosity reduction), 4 parts of polyamide wax DeuRheo 229, 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGELS9, 15 parts of diatomaceous earth, 10 parts of porous alumina, 14 parts of 800 mesh talc, 10 parts of zirconium phosphate and 8 parts of nano titanium dioxide.

[0043] Specifically, component B includes, by mass: 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213, 1 part of dispersant H-3110, 1 part of bentonite PANGEL S9 (produced by TOLSA GROUP), 12 parts of porous alumina, 8 parts of zirconium phosphate, 34 parts of 800 mesh talc and 8 parts of nano titanium dioxide.

[0044] The preparation method of the breathable epoxy sealing primer for concrete provided in this embodiment 1 has the following steps: Step 1: Disperse 15 parts of epoxy resin E-51, 12 parts of aliphatic polyether modified epoxy resin, 9 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110, and 4 parts of polyamide wax DeuRheo 229 under 1500rpm / min high-speed dispersion conditions for 15 minutes, then slowly add 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 15 parts of diatomaceous earth, 10 parts of porous alumina, 14 parts of 800 mesh talc, 10 parts of zirconium phosphate, and 8 parts of nano titanium dioxide, and maintain high-speed dispersion at 2500rpm / min for 1 hour to obtain component A; the hyperbranched epoxy toughening resin CYH-277 in component A accounts for 25% of the mass fraction of the total resin system.

[0045] Step 2: Disperse 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213 and 1 part of dispersant H-3110 at 1500 rpm / min high-speed dispersion conditions for 15 minutes, then slowly add 1 part of bentonite PANGEL S9, 12 parts of porous alumina, 8 parts of zirconium phosphate, 34 parts of 800 mesh talc, and 8 parts of nano titanium dioxide, and continue to disperse at 2500 rpm / min for 1 hour to obtain component B.

[0046] Step 3: Evenly mix component A and component B in a mass ratio of 2:1 to obtain a breathable epoxy sealing primer for concrete.

[0047] Example 2 (in component A, the hyperbranched epoxy toughening resin CYH-277 accounts for 20% of the total resin mass fraction): This embodiment 2 provides a breathable epoxy sealing primer for concrete, including component A and component B. Component A and component B are evenly mixed in a ratio of 2:1 to obtain the breathable epoxy sealing primer.

[0048] Specifically, component A includes, by mass: 16.8 parts of epoxy resin E-51, 12 parts of aliphatic polyether modified epoxy resin, 7.2 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110, 4 parts of polyamide wax DeuRheo 229, 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 12 parts of diatomaceous earth, 8 parts of porous alumina, 19 parts of 800 mesh talc, 8 parts of zirconium phosphate and 10 parts of nano titanium dioxide.

[0049] Specifically, component B includes, by mass, 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213, 1 part of dispersant H-3110, 1 part of bentonite PANGEL S9, 10 parts of porous alumina, 6 parts of zirconium phosphate, 38 parts of 800 mesh talc and 8 parts of nano titanium dioxide.

[0050] The preparation method of the breathable epoxy sealing primer for concrete provided in this embodiment 2 has the following steps: Step 1: 16.8 parts of epoxy resin E-51, 12 parts of aliphatic polyether modified epoxy resin, 7.2 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110, and 4 parts of polyamide wax DeuRheo 229 are dispersed under 1500rpm / min high-speed dispersion conditions for 15 minutes, and then 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 12 parts of diatomaceous earth, 8 parts of porous alumina, 19 parts of 800 mesh talc, 8 parts of zirconium phosphate, and 10 parts of nano titanium dioxide are slowly added, and component A is obtained after maintaining high-speed dispersion at 2500rpm / min for 1 hour.

[0051] Step 2: Disperse 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213 and 1 part of dispersant H-3110 at 1500 rpm / min for 15 minutes, then slowly add 1 part of bentonite PANGEL S9, 10 parts of porous alumina, 6 parts of zirconium phosphate, 38 parts of 800 mesh talc, and 8 parts of nano titanium dioxide, and continue to disperse at 2500 rpm / min for 1 hour to obtain component B.

[0052] Step 3: Evenly mix component A and component B in a mass ratio of 2:1 to obtain a breathable epoxy sealing primer for concrete.

[0053] Example 3 (in component A, the hyperbranched epoxy toughening resin CYH-277 accounts for 15% of the total resin mass fraction): This embodiment 3 provides a breathable epoxy sealing primer for concrete, including component A and component B. Component A and component B are evenly mixed in a ratio of 2:1 to obtain the breathable epoxy sealing primer.

[0054] Specifically, component A includes, by mass: 18.6 parts of epoxy resin E-51, 12 parts of aliphatic polyether modified epoxy resin, 5.4 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110, 4 parts of polyamide wax DeuRheo 229, 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 10 parts of diatomaceous earth, 8 parts of porous alumina, 23 parts of 800 mesh talc, 6 parts of zirconium phosphate and 10 parts of nano titanium dioxide.

[0055] Specifically, component B includes, by mass, 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213, 1 part of dispersant H-3110, 1 part of bentonite PANGEL S9, 8 parts of porous alumina, 4 parts of zirconium phosphate, 42 parts of 800 mesh talc and 8 parts of nano titanium dioxide.

[0056] The preparation method of the breathable epoxy sealing primer for concrete provided in this embodiment 3 has the following steps: Step 1: 18.6 parts of epoxy resin E-51, 12 parts of aliphatic polyether modified epoxy resin, 5.4 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110, and 4 parts of polyamide wax DeuRheo 229 are dispersed under 1500rpm / min high-speed dispersion conditions for 15 minutes, and then 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 10 parts of diatomaceous earth, 8 parts of porous alumina, 23 parts of 800 mesh talc, 6 parts of zirconium phosphate, and 10 parts of nano titanium dioxide are slowly added, and component A is obtained after maintaining high-speed dispersion at 2500rpm / min for 1 hour.

[0057] Step 2: Disperse 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213 and 1 part of dispersant H-3110 at 1500 rpm / min for 15 minutes, then slowly add 1 part of bentonite PANGEL S9, 8 parts of porous alumina, 4 parts of zirconium phosphate, 42 parts of 800 mesh talc, and 8 parts of nano titanium dioxide, and continue to disperse at 2500 rpm / min for 1 hour to obtain component B.

[0058] Step 3: Evenly mix component A and component B in a mass ratio of 2:1 to obtain a breathable epoxy sealing primer for concrete.

[0059] Comparative Example 1 (component A does not contain hyperbranched epoxy toughening resin CYH-277): Comparative Example 1 provides an epoxy sealing primer for concrete, including component A and component B. Component A and component B are evenly mixed in a ratio of 2:1 to obtain a breathable epoxy sealing primer.

[0060] Specifically, component A includes, by mass, 24 parts of epoxy resin E-51, 12 parts of aliphatic polyether modified epoxy resin, 1 part of dispersant H-3110, 4 parts of polyamide wax DeuRheo 229, 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 15 parts of diatomaceous earth, 10 parts of porous alumina, 14 parts of 800 mesh talc, 10 parts of zirconium phosphate and 8 parts of nano titanium dioxide.

[0061] Specifically, component B includes, by mass, 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213, 1 part of dispersant H-3110, 1 part of bentonite PANGEL S9, 12 parts of porous alumina, 8 parts of zirconium phosphate, 34 parts of 800 mesh talc and 8 parts of nano titanium dioxide.

[0062] The preparation method of the breathable epoxy sealing primer for concrete provided in Comparative Example 1 has the following steps: Step 1: Disperse 24 parts of epoxy resin E-51, 12 parts of aliphatic polyether modified epoxy resin, 1 part of dispersant H-3110, and 4 parts of polyamide wax DeuRheo 229 at 1500rpm / min for 15 minutes, then slowly add 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 15 parts of diatomaceous earth, 10 parts of porous alumina, 14 parts of 800 mesh talc, 10 parts of zirconium phosphate, and 8 parts of nano titanium dioxide, and maintain high-speed dispersion at 2500rpm / min for 1 hour to obtain component A.

[0063] Step 2: Disperse 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213 and 1 part of dispersant H-3110 at 1500 rpm / min high-speed dispersion conditions for 15 minutes, then slowly add 1 part of bentonite PANGEL S9, 12 parts of porous alumina, 8 parts of zirconium phosphate, 34 parts of 800 mesh talc, and 8 parts of nano titanium dioxide, and continue to disperse at 2500 rpm / min for 1 hour to obtain component B.

[0064] Step 3: Evenly mix component A and component B in a mass ratio of 2:1 to obtain a breathable epoxy sealing primer for concrete.

[0065] Comparative Example 2 (without diatomaceous earth, porous alumina and zirconium phosphate): Comparative Example 2 provides an epoxy sealing primer for concrete, including component A and component B. Component A and component B are evenly mixed in a ratio of 2:1 to obtain a breathable epoxy sealing primer.

[0066] Specifically, component A includes, by mass: 15 parts of epoxy resin E-51, 12 parts of aliphatic polyether modified epoxy resin, 9 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110, 4 parts of polyamide wax DeuRheo 229, 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 15 parts of diatomaceous earth, 10 parts of porous alumina, 47 parts of 800 mesh talc and 10 parts of nano titanium dioxide.

[0067] Specifically, component B includes, by mass, 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213, 1 part of dispersant H-3110, 1 part of bentonite PANGEL S9, 54 parts of 800-mesh talc powder and 8 parts of nano titanium dioxide.

[0068] The preparation method of the breathable epoxy sealing primer for concrete provided in Comparative Example 2 has the following steps: Step 1: 15 parts of epoxy resin E-51E-51, 12 parts of aliphatic polyether modified epoxy resin, 9 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110, and 4 parts of polyamide wax DeuRheo 229 are dispersed at 1500rpm / min high-speed dispersion conditions for 15 minutes, and then 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 47 parts of 800 mesh talc, and 10 parts of nano titanium dioxide are slowly added, and high-speed dispersion is maintained at 2500rpm / min for 1 hour to obtain component A.

[0069] Step 2: Disperse 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213 and 1 part of dispersant H-3110 at 1500 rpm / min for 15 minutes, then slowly add 1 part of bentonite PANGEL S9, 54 parts of 800 mesh talc, and 8 parts of nano titanium dioxide, and continue to disperse at 2500 rpm / min for 1 hour to obtain component B.

[0070] Step 3: Evenly mix component A and component B in a mass ratio of 2:1 to obtain a breathable epoxy sealing primer for concrete.

[0071] Comparative Example 3 (based on Example 1, the mass content of the hyperbranched epoxy toughening resin CYH-277 and the porous filler was halved): Comparative Example 3 provides a breathable epoxy sealing primer for concrete, including component A and component B. Component A and component B are evenly mixed in a ratio of 2:1 to obtain the breathable epoxy sealing primer.

[0072] Specifically, component A includes, by mass: 16.5 parts of epoxy resin E-51, 15 parts of aliphatic polyether modified epoxy resin, 4.5 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110 (produced by Huihang Trading, with obvious viscosity reduction), 4 parts of polyamide wax DeuRheo 229, 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 7.5 parts of diatomaceous earth, 5 parts of porous alumina, 31.5 parts of 800 mesh talc, 5 parts of zirconium phosphate and 8 parts of nano titanium dioxide.

[0073] Specifically, component B includes, by mass: 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213, 1 part of dispersant H-3110, 1 part of bentonite PANGEL S9 (produced by TOLSA GROUP), 6 parts of porous alumina, 4 parts of zirconium phosphate, 44 parts of 800 mesh talc and 8 parts of nano titanium dioxide.

[0074] The preparation method of the breathable epoxy sealing primer for concrete provided in this embodiment 1 has the following steps: Step 1: Disperse 16.5 parts of epoxy resin E-51, 15 parts of aliphatic polyether modified epoxy resin, 4.5 parts of hyperbranched epoxy toughening resin CYH-277, 1 part of dispersant H-3110, and 4 parts of polyamide wax DeuRheo 229 at 1500rpm / min high-speed dispersion conditions for 15 minutes, then slowly add 1 part of polydimethylsiloxane WE-D9000, 1 part of bentonite PANGEL S9, 7.5 parts of diatomaceous earth, 5 parts of porous alumina, 31.5 parts of 800 mesh talc, 5 parts of zirconium phosphate, and 8 parts of nano titanium dioxide, and maintain high-speed dispersion at 2500rpm / min for 1h to obtain component A.

[0075] Step 2: Disperse 36 parts of cardanol-modified phenolic amine curing agent CARLOS-2213 and 1 part of dispersant H-3110 at 1500 rpm / min for 15 minutes, then slowly add 1 part of bentonite PANGEL S9, 6 parts of porous alumina, 4 parts of zirconium phosphate, 44 parts of 800 mesh talc, and 8 parts of nano titanium dioxide, and continue to disperse at 2500 rpm / min for 1 hour to obtain component B.

[0076] Step 3: Evenly mix component A and component B in a mass ratio of 2:1 to obtain a breathable epoxy sealing primer for concrete.

[0077] Specifically, the epoxy sealing primers prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were tested for mechanical properties such as workability, flexibility, tensile strength, water resistance, and adhesion, and the water vapor transmission rate was measured according to the standard JG / T 309-2011 "Determination and classification of water vapor transmission rate of exterior wall coatings", as shown in Table 1 below: Table 1

[0078] Furthermore, it can be seen from Table 1 that the difference between Comparative Example 1 and Example 1 is that the hyperbranched epoxy toughening resin CYH-277 is not added, the flexibility of the paint film of Comparative Example 1 is significantly reduced, it is more prone to cracking, the wettability to the porous filler is reduced and the viscosity is relatively large, the impact toughness and tensile strength are also significantly reduced, and the water vapor permeability is also significantly low.

[0079] Furthermore, it can be seen from Table 1 that the difference between Comparative Example 2 and Example 1 is that no porous filler particles (diatomaceous earth, porous alumina and zirconium phosphate) are added, and performance tests show that flexibility, tensile strength and impact toughness are slightly reduced, and adhesion is also significantly reduced. The most obvious difference is that the water vapor permeability is significantly reduced.

[0080] Furthermore, it can be seen from Table 1 that the difference between Comparative Example 3 and Example 1 is that the dosage of the hyperbranched epoxy toughening resin CYH-277 and the porous filler particles is reduced by half, the tensile strength and impact toughness are reduced, the alkali resistance and salt spray resistance are reduced, and the concrete cannot be protected. The water vapor permeability is also significantly different from that of Example 1.

[0081] The present invention aims to provide a microporous structure breathable waterproof flexible epoxy sealing primer for concrete, which is used as a solvent-free epoxy system and is suitable for construction methods such as spraying, scraping and roller coating. The mechanism of the breathable epoxy sealing primer of the present invention is that a flexible long-chain modified epoxy resin with aliphatic modification and a hyperbranched epoxy toughening agent are combined with a modified amine curing agent to form a multi-branched bridge-type network structure, and a micro-nano porous structure filler is embedded to form a breathable epoxy sealing primer by utilizing the hole network structure formed by the mutual intersection between the resins. The outer surface of the primer also has a certain hydrophobicity, which can prevent external water from entering the interior of the paint film and causing damage to the concrete.

[0082] The sealing primer of the present invention can effectively solve the problem of smooth integrity of the paint film when the gas in the internal voids of the concrete is squeezed out after the sealing paint is applied, and the gas remaining in the voids after curing can also freely overflow through the microporous structure inside the paint film, and the paint film is waterproof, which can prevent external moisture from returning to the inside of the paint film. At the same time, it also has excellent flexibility, higher tensile strength, good corrosion resistance, and strong adhesion, which can better protect the concrete from cracking and corrosion. This product can also play a role in replacing two-component epoxy putty, reducing the coating process in multiple systems and saving coating costs.

[0083] The present invention uses small molecule epoxy resin, aliphatic polyether modified epoxy resin and hyperbranched epoxy toughening resin as main film-forming resins, and solidifies with cardanol modified phenolic amine curing agent to form an interpenetrating multi-branched bridge-type network structure with holes, in which a filler with a microporous structure is embedded, thereby obtaining a highly flexible coating that is breathable and waterproof. The coating is a solvent-free environmentally friendly coating, has excellent adhesion to concrete substrates, significantly improves tensile strength, and also reaches an intermediate level of water vapor permeability.

[0084] It should be noted that the above embodiments all belong to the same inventive concept, and the description of each embodiment has its own focus. For details not described in individual embodiments, reference may be made to the description in other embodiments.

[0085] The above embodiments only express the implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A breathable epoxy sealing primer for concrete, characterized in that: The invention comprises a component A and a component B, wherein the component A comprises, by weight: 10 to 25 parts of a small molecule epoxy resin, 8 to 15 parts of an aliphatic polyether modified epoxy resin, 5 to 15 parts of a hyperbranched epoxy toughening resin, 1 to 3 parts of a dispersant, 1 to 2 parts of a surface additive, 2 to 8 parts of a polyamide wax, 0.5 to 1 part of an organic modified bentonite, 5 to 15 parts of diatomaceous earth, 5 to 15 parts of porous alumina, 10 to 50 parts of talc, 5 to 10 parts of zirconium phosphate and 5 to 10 parts of nano titanium dioxide; The B component comprises, by mass, 20 to 40 parts of a modified amine curing agent, 1 to 3 parts of the dispersant, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of porous alumina, 2 to 10 parts of zirconium phosphate, 30 to 60 parts of talc and 5 to 10 parts of nano titanium dioxide.

2. The breathable epoxy sealing primer for concrete according to claim 1, characterized in that: The mass ratio of the component A to the component B is (1.5~2):

1.

3. The breathable epoxy sealing primer for concrete according to claim 1, characterized in that: The small molecule epoxy resin is epoxy resin E51; the aliphatic polyether modified epoxy resin is prepared by reacting and modifying the small molecule epoxy resin with aliphatic difunctional glycidyl ether.

4. The breathable epoxy sealing primer for concrete according to claim 3, characterized in that: The aliphatic difunctional glycidyl ether is at least one of 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether and neopentyl glycol diglycidyl ether.

5. The breathable epoxy sealing primer for concrete according to claim 1, characterized in that: The hyperbranched epoxy toughening resin is alicyclic polymer CYH-277, the dispersant is high molecular polymer dispersant H-3110, and the model of polyamide wax is DeuRheo 229 or CANFAIR229.

6. The breathable epoxy sealing primer for concrete according to claim 1, characterized in that: The surface additive is polydimethylsiloxane WE-D9000.

7. The breathable epoxy sealing primer for concrete according to claim 1, characterized in that: The modified amine curing agent is cardanol modified phenolic amine curing agent CARLOS-2213, and the active hydrogen equivalent AHEW is 90-100.

8. The breathable epoxy sealing primer for concrete according to claim 1, characterized in that: The particle size of the talcum powder is 400-1250 meshes.

9. A method for preparing a breathable epoxy sealing primer for concrete according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: S10, according to the formula mass ratio, 10 to 25 parts of a small molecule epoxy resin, 8 to 15 parts of the aliphatic polyether modified epoxy resin, 5 to 15 parts of the hyperbranched epoxy toughening resin, 1 to 3 parts of the dispersant and 2 to 8 parts of polyamide wax are mixed and dispersed, and during the dispersion process, 1 to 2 parts of the surface additive, 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of diatomaceous earth, 5 to 15 parts of porous alumina, 10 to 50 parts of talc, 5 to 10 parts of zirconium phosphate and 5 to 10 parts of nano titanium dioxide are slowly added to obtain the A component; S20, mixing 20 to 40 parts of the modified amine curing agent with 1 to 3 parts of the dispersant according to the formula mass ratio and performing dispersion treatment, and slowly adding 0.5 to 1 part of organic modified bentonite, 5 to 15 parts of porous alumina, 2 to 10 parts of zirconium phosphate, 30 to 60 parts of talc and 5 to 10 parts of nano titanium dioxide during the dispersion treatment to obtain the B component; S30, mixing the component A and the component B in a mass ratio of (1.5-2):1 to obtain the breathable epoxy sealing primer for concrete.

10. The method for preparing the breathable epoxy sealing primer for concrete according to claim 9, characterized in that: In the step S10, the preparation process of the aliphatic polyether modified epoxy resin is as follows: Add epoxy resin E51, bisphenol A, aliphatic difunctional glycidyl ether and xylene into a reaction bottle, heat to 125°C, and add catalyst triphenylphosphonium iodide; After that, the temperature is raised to 150° C. for half an hour and kept for 2 to 4 hours. When the epoxy value reaches 0.30 to 0.33 mol / 100 g, the temperature is lowered to 80° C. and subjected to rotary evaporation to obtain the solvent-free aliphatic polyether modified epoxy resin.

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