A kind of anti-freeze-thaw beautification marking polyasparagus protective material used in pumped storage power station and its preparation method

Abstract

The present invention relates to the technical field of polyurea materials, particularly a polyaspartic acid protective material for freeze-thaw protection and beautification marking used in pumped-storage power stations, and a preparation method thereof. The method comprises: S1, synthesis of a silane-modified nanoparticle composition; S2, synthesis of a nanoparticle-modified polyaspartic acid ester; S3, preparation of a polyisocyanate curing agent; and S4, synthesis of the polyaspartic acid protective material. The present invention uses a silane coupling agent to modify an acidified hydrophobic nanoparticle composition. The silane-modified nanoparticle composition is then pre-dispersed in two parts, respectively, into the polyaspartic acid ester and the polyisocyanate curing agent, achieving uniform dispersion within the system. The uniformly dispersed nanoparticle composition synergistically interacts with the fluorocarbon resin and the hydrophobic system, significantly reducing adhesion to ice while ensuring excellent adhesion and impact resistance of the coating, thereby significantly improving the material's freeze-thaw resistance.

Description

Technical Field

[0001] The invention relates to the technical field of polyurea materials, in particular to a freeze-thaw-proof beautification marking polyasparagus protective material used in a pumped storage power station and a preparation method thereof. Background Art

[0002] Due to the high altitude, complex geological conditions, and harsh climatic conditions of pumped-storage power stations, reservoir basins are prone to leakage, which affects the normal operation of the power stations. Since its introduction, polyurea materials have gradually been recognized and understood in various fields and are now gradually being promoted and applied in hydropower station projects for anti-seepage, surface protection, and anti-scour. In winter, when the reservoir freezes over, the ice layer adheres to the polyurea protective layer. As the reservoir water level fluctuates, the thick ice layer will pull, push, and impact the polyurea protective layer, which can easily cause damage to the polyurea protective layer. Therefore, the use of polyurea materials in high-altitude and cold regions requires not only excellent impact resistance and anti-seepage properties, but more importantly, high freeze-thaw resistance.

[0003] The fluorine atoms in fluorine-containing materials have strong electronegativity and high-energy carbon-fluorine bonds, which can well protect the main chain of the macromolecule, giving the material good surface properties and excellent electrical properties. In addition, organic fluorine also has a very good effect in hydrophobicity. The existing technology uses fluorine modification to produce fluorinated polyurea, making its hydrophobicity even better. For example, Chinese invention patent application No. 202211458110.3 (publication No. CN 115895410 A) proposes a one-component polyurea anti-ice pullout coating and its preparation method. The coating comprises, by weight, 55-80 parts of a perfluorinated hydrophobic prepolymer, 10-25 parts of a latent curing agent, 5-15 parts of a pigment or filler, and 0.5-1 part of a catalyst A. The perfluorinated hydrophobic prepolymer is prepared by reacting 10-50 parts by weight of an isocyanate monomer, 20-70 parts by weight of a hydrophobic polyol, 5-10 parts by weight of a perfluoropolyether alcohol, 5-20 parts by weight of a solvent, and 0.2-2.5 parts by weight of a catalyst B at 65-100°C for 3-4 hours under an inert atmosphere. Generally speaking, one-component polyurea is used for anti-seepage treatment of reservoir concrete slabs, cracks in dam bodies, and structural joints. So far, there are few reports on the application of two-component polyurea in large-area anti-seepage treatment of reservoir surfaces and dam water-facing surfaces, and there are even fewer two-component polyureas with excellent anti-ice pullout performance.

[0004] Like fluorine modification, nano-modification is also an effective method to improve the function of polyurea materials. Nanomaterials have special properties such as surface effects and macroscopic quantum size effects. Therefore, adding nanomaterials to polyurea can improve its strength, thermal stability, carbonization resistance, impact resistance and other properties. In the prior art, hydrophobic nanoparticles are used to form a hydrophobic super-hydrophobic layer by mixing them with resin and solidifying them into a film to reduce the adhesion between the polyurea material and the ice layer and reduce ice pull damage. However, it is well known that nanoparticles have poor dispersibility and are wrapped by an organic coating after addition. They can only play a certain auxiliary role. Their main function is still the hydrophobicity of the resin system itself, and they cannot effectively exert their hydrophobic effect.

[0005] For this purpose, this application is filed. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides an anti-freeze-thaw beautification marking polyasparagus protective material for use in pumped storage power stations and a preparation method thereof.

[0007] In order to achieve the above objectives, the main technical solutions adopted by the present invention include:

[0008] A method for preparing a freeze-thaw-proof beautification marking polyasparagus protective material used in a pumped storage power station comprises the following steps:

[0009] S1. Synthesis of Silane-Modified Nanoparticle Composition

[0010] The hydrophobic nanoparticle composition is added to an aromatic polyacid, heated to 40-50° C. and ultrasonicated for more than 45 minutes, then allowed to stand and centrifuged to obtain a precipitate;

[0011] The silane coupling agent is added to an ethanol aqueous solution, heated to 50-60° C. and kept refluxed for 2-4 hours, then the precipitate and the organotin esterification catalyst are added, the temperature is raised to 170-175° C. and kept refluxed for 6-8 hours, cooled to room temperature, allowed to stand, centrifuged, washed with anhydrous ethanol and acetone in sequence, and finally vacuum dried to obtain a silane-modified nanoparticle composition; the structural formula of the silane coupling agent is as follows:

[0012] ;

[0013] In this step, the nanoparticle composition is added to the aromatic polyacid and then ultrasonically acidified. The aromatic polyacid is used to acidify the nanoparticle composition, so that the nanoparticle composition has a large number of carboxyl groups on its surface, and is also used to acidify the silane coupling agent, so that it is hydrolyzed in an ethanol aqueous solution to form a silanol with multiple hydroxyl groups at both ends. The hydroxyl groups and the carboxyl groups undergo an esterification reaction under the action of an organic tin esterification catalyst such as monobutyltin oxide, dibutyltin oxide, dibutyltin dilaurate, etc. to form multiple ester groups, so that the silane coupling agent is stably grafted to the nanoparticle composition in a chemical bonding manner to obtain a silane-modified nanoparticle composition. Since the silane-modified nanoparticle composition contains a large number of oxygen-containing functional groups, it can have good dispersibility in the resin on the one hand, and can provide a large number of reactive sites on the other hand, thereby forming a stable chemical bond with the polymer.

[0014] It should be noted that the ultrasonication time of the nanoparticle composition in the aromatic polyacid is not less than 45 minutes. The present invention unexpectedly discovered that when the ultrasonication time is insufficient, the degree of acidification of the nanoparticle composition is insufficient, which is not conducive to the hydrolysis of the silane coupling agent and the esterification reaction.

[0015] In addition, the silane coupling agent used in the present invention contains amino groups and multiple hydroxyl groups. The difference in the reactivity of the groups enables them to be evenly distributed in the molecular chain, thereby further improving the dispersibility of the nanoparticle composition chemically bonded thereto; moreover, it can also enhance the adhesion of the final film on the substrate, eliminating the need for the subsequent addition of an adhesion promoter;

[0016] S2. Synthesis of Nanoparticle-Modified Polyaspartic Acid

[0017] Under nitrogen protection, the silane-modified nanoparticle composition, proline, and 4,4'-diaminodicyclohexylmethane were mixed, and the temperature was raised to 70-80°C while stirring. Then, diethyl maleate was slowly added. After the addition was completed, the temperature was raised to 100-110°C, and the reaction was carried out for at least 10 hours to obtain nanoparticle-modified polyaspartic acid ester;

[0018] In this step, proline catalyzes the reaction of 4,4'-diaminodicyclohexylmethane and diethyl maleate to form polyaspartic acid ester. Adding a portion of the silane-modified nanoparticle composition during this process, through pre-mixing with the polyurea system, not only improves the final dispersion effect and enhances its interfacial bonding strength with the system, but also increases the active sites of the subsequent polyurea formation reaction, promotes the formation of more stable chemical bonds in the polyurea, and improves the performance of the polyurea material.

[0019] S3. Preparation of polyisocyanate curing agent

[0020] Mixing an aliphatic polyisocyanate curing agent, at least one aromatic polyisocyanate curing agent, and the silane-modified nanoparticle composition and stirring them uniformly to obtain the polyisocyanate curing agent;

[0021] Through this step, another portion of the silane-modified nanoparticle composition is evenly dispersed in the polyisocyanate curing agent. Premixing the silane-modified nanoparticle composition with the polyisocyanate curing agent improves the dispersion effect and enhances the interfacial bonding strength. It also increases the active sites for the polyurea formation reaction, further promoting the formation of more stable chemical bonds in the polyurea. This improves the performance of the polyurea material while allowing the nanoparticle composition to effectively exert its hydrophobic effect.

[0022] S4. Synthesis of Polyasparagus Protective Materials

[0023] The polyisocyanate curing agent is used as component A; the nanoparticle-modified polyaspartic acid ester is mixed with a fluorocarbon resin, a pigment, an additive, and a hydrophobic plasticizer, and then ground to obtain component B; when used, components A and B are mixed and stirred evenly, polymerized at room temperature, and sprayed for molding.

[0024] Compared with the prior art, the present invention uses a silane coupling agent to modify the acidified hydrophobic nanoparticle composition, and divides the silane-modified nanoparticle composition into two parts, which are pre-dispersed in polyaspartic acid ester and polyisocyanate curing agent respectively, thereby achieving uniform dispersion thereof in the system. The uniformly dispersed nanoparticle composition synergizes with the fluorocarbon resin and the hydrophobic system, and the obtained polyaspartic acid protective material has low surface energy and a small friction coefficient, making its surface super-hydrophobic. While ensuring the excellent adhesion and impact resistance of the coating, the adhesion to ice is greatly reduced, the anti-ice pull effect is enhanced, and the freeze-thaw resistance of the material is significantly improved.

[0025] Preferably, in S1, the aromatic polyacid is an aromatic polyacid containing at least one benzene ring, preferably an aromatic polyacid having a benzene ring structure substituted with multiple carboxyl groups and multiple phenyl groups;

[0026] The aromatic polyacid is specifically selected from terephthalic acid, isophthalic acid, 3,5-dicarboxychlorobenzene, 3,3',5,5'-biphenyltetracarboxylic acid, 3,3',5,5'-azobenzenetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylacetylene-3,3',5,5'-tetracarboxylic acid, triphenylmethanetricarboxylic acid, terphenyldicarboxylic acid, [1,1':3',1"-terphenyl]-3,4",5 -tricarboxylic acid, 1,3,5-tris(4-carboxyphenyl)benzene, 1,2,4,5-tetrakis(4-carboxyphenyl)benzene, preferably 3,3',5,5'-azobenzenetetracarboxylic acid, diphenylacetylene-3,3',5,5'-tetracarboxylic acid, terphenyldicarboxylic acid, [1,1':3',1"-terphenyl]-3,4",5-tricarboxylic acid, 1,3,5-tris(4-carboxyphenyl)benzene, 1,2,4,5-tetrakis(4-carboxyphenyl)benzene.

[0027] Through this embodiment, the silane-modified nanoparticle composition not only stably connects to the silane coupling agent through multiple ester groups, but also contains a large number of benzene rings. When it is used in the preparation of polyisocyanate curing agents, it has good compatibility with aromatic polyisocyanate curing agents, which helps to promote uniform blending and improve the fluidity of the system. Moreover, when an aromatic polyacid having a benzene ring structure substituted with multiple carboxyl groups and multiple phenyl groups is selected, such as 3,3',5,5'-azobenzenetetracarboxylic acid and diphenylacetylene-3,3',5,5'-tetracarboxylic acid with an unsaturated bond and two benzene ring structures, its unsaturated bond and two benzene rings form a good conjugation with the nitrogen-oxygen six-membered ring in each structural unit of polyaspartic acid ester, and terphenyl dicarboxylic acid, [1,1':3',1"-terphenyl]-3,4",5-tricarboxylic acid, 1,3,5-tris(4- (4-carboxyphenyl) benzene, 1,2,4,5-tetrakis (4-carboxyphenyl) benzene, the benzene ring topology structure provided by it is conducive to forming good conjugation with the nitrogen oxide six-membered ring in each structural unit of polyaspartic acid ester; good conjugation makes the silane-modified nanoparticle composition better dispersed in the system, and electrons move freely in the entire conjugated system, so that the carbon-carbon bonds in the conjugated system show a certain degree of homogenization, which not only helps to improve the reaction activity, but also can improve the stability of the product to a certain extent, improve its water resistance, corrosion resistance and mechanical properties. Preferably, in S3, the aliphatic polyisocyanate curing agent and the aromatic polyisocyanate curing agent are used as reaction substrates, the content of the aliphatic polyisocyanate curing agent is 55-65wt%, and the addition amount of the silane-modified nanoparticle composition is 0.5-3wt% of the reaction substrate.

[0028] The cured products of aliphatic polyisocyanate curing agents have high strength and hardness, good corrosion resistance, and good low-temperature curing properties, but relatively poor weather resistance. Cured products of aromatic polyisocyanate curing agents have excellent weather resistance. Through this embodiment, the resulting polyisocyanate curing agent is cured with polyaspartic acid ester, resulting in a high density of urea bonds per unit volume, resulting in a polyaspartic acid protective material with excellent weather resistance, impact resistance, and corrosion resistance.

[0029] Taking into account both the cost and effect of adding the silane-modified nanoparticle composition, the preferred addition amount of the silane-modified nanoparticle composition in the polyisocyanate curing agent is 2-5wt%. At this addition amount, the silane-modified nanoparticle composition is uniformly blended and dispersed with the other components in the polyisocyanate curing agent, thereby better exerting the hydrophobic effect.

[0030] Preferably, in S2, 4,4'-diaminodicyclohexylmethane and diethyl maleate are used as reaction substrates, the added amount of 4,4'-diaminodicyclohexylmethane is 60-70wt% of the reaction substrate, the added amount of the silane-modified nanoparticle composition is 0.5-3wt% of the reaction substrate, and the added amount of proline is 3-6wt% of the reaction substrate. Proline can positively catalyze the synthesis of polyaspartic acid ester, significantly accelerate the reaction process, and improve the conversion rate of the reaction.

[0031] Further preferably, the aliphatic polyisocyanate curing agent and the aromatic polyisocyanate curing agent are compounded in a mass ratio of 1.5:1, which has a better effect on improving the weather resistance of the cured product.

[0032] Further preferably, the aliphatic polyisocyanate curing agent is hexamethylene diisocyanate, and the aromatic polyisocyanate curing agent is selected from at least one of p-phenylene diisocyanate, m-phenylene diisocyanate, toluene-2,6-diisocyanate, diphenylmethane-4,4'-diisocyanate, chlorobenzene-2,4-isocyanate, naphthalene-1,5-diisocyanate, biphenyl-4,4'-diisocyanate, 3-methyldiphenylmethane-4,4'-diisocyanate, diphenyl ether diisocyanate, and triphenylmethane triisocyanate.

[0033] The aromatic polyisocyanate curing agent contains a benzene ring, which helps to improve the uniformity of its blending with the silane-modified nanoparticle composition containing a benzene ring. When the aromatic polyisocyanate curing agent contains the same benzene ring structure as the aromatic polyacid, the similar compatibility of the two helps the silane-modified nanoparticle composition to be evenly dispersed in the polyisocyanate curing agent.

[0034] Preferably, in order to promote a relatively complete reaction of the polyaspartic acid ester, the polyisocyanate curing agent is appropriately excessive, and in S4, the molar ratio of -NCO in component A to -NH in component B is 1.06-1.08.

[0035] Preferably, in S1, the nanoparticle composition is a composition of nano-silicon dioxide and nano-zirconium dioxide, and the preferred mass ratio of nano-silicon dioxide and nano-zirconium dioxide is (1-5):1; the ethanol aqueous solution is an ethanol aqueous solution with a volume ratio of 1:1; after centrifugation, the solution is washed once with anhydrous ethanol and then twice with acetone, and the vacuum drying temperature does not exceed 45°C.

[0036] Preferably, in S4, the fluorine content of the fluorocarbon resin is ≥26%, specifically selected from at least one of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, and polyvinyl fluoride; the pigment is at least one of titanium dioxide, barium dioxide, zinc white, iron red, iron yellow, chrome yellow, iron black, carbon black and organic pigments; the auxiliary agent is at least one of a defoaming agent, a wetting agent, a leveling agent, and a thickener; the content of each component in the B component is: 50-60wt% of the nanoparticle-modified polyaspartic acid ester, 20-30wt% of the fluorocarbon resin, 2-10wt% of the pigment, 0.1-10wt% of the auxiliary agent, and 3-10wt% of the hydrophobic plasticizer.

[0037] With this implementation:

[0038] (1) High-fluorine-containing fluorocarbon resins with a fluorine content of ≥26% have excellent cold resistance, water resistance, weather resistance, chemical corrosion resistance, and mechanical properties. When compounded with a silane-modified nanoparticle composition, the resulting polyasparagine protective material has extremely low surface energy and strong hydrophobicity, making it difficult for ice to stably bind to it, and even if it does, it is not strong, thereby effectively reducing ice pull damage and greatly improving the material's freeze-thaw resistance. Moreover, it can further improve the poor weather resistance of products cured with aliphatic polyisocyanate curing agents.

[0039] (2) By adding pigments of specific colors, it can be used to beautify and mark the surface of the reservoir and the water-facing surface of the dam while providing large-scale waterproofing and anti-seepage treatment;

[0040] (3) Defoamers, wetting agents, leveling agents, thickeners, hydrophobic plasticizers, etc. are all existing technologies. The defoamer is preferably defoamer BYK-9920, the wetting agent is preferably polyether-modified polydimethylsiloxane, the leveling agent is preferably an acrylic copolymer leveling agent, the thickener is preferably a non-ionic polyurethane associative thickener, and the hydrophobic plasticizer is preferably one or more of dioctyl phthalate, dioctyl terephthalate, and dioctyl adipate.

[0041] In another aspect, the present invention provides a polyasparagus protective material for freeze-thaw protection and beautification marking. Testing has shown that this polyasparagus protective material has a solids content of ≥83%, a surface dry time of ≤1.5 hours, a contact angle of 134°-155°, a water absorption rate of ≤0.6%, adhesion of ≥21.9 MPa, tensile strength of ≥27.9 MPa, elongation at break of ≥339%, and a tear strength of ≥54 N / m.

[0042] The anti-freeze-thaw beautification marking polyasparagus protective material used in pumped storage power stations of the present invention is specially used for large-area anti-seepage treatment of reservoir surfaces and dam water-facing surfaces. The construction is simple, the bonding strength with ice is poor, and the freeze-thaw resistance is good. The material can be used in pumped storage power stations in my country's high-altitude cold regions. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0044] Figure 1 This is a photo of a pumped storage power station in Jilin Province before spraying with the polyasparagus protective material described in Example 1 of the present invention;

[0045] Figure 2 This is a photo of a pumped storage power station in Jilin Province after being sprayed with the polyasparagus protective material described in Example 1 of the present invention;

[0046] Figure 3 These are photos of a pumped-storage power station in Jilin Province after it was sprayed with the polyasparagus protective material described in Example 1 of the present invention and experienced three winters. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, and are not all embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0048] In the following examples and comparative examples: nanosilica was purchased from Henan Wangwu Nanotechnology Co., Ltd., product model DNS-3; nanozirconium dioxide was purchased from Henan Wangwu Nanotechnology Co., Ltd., product model DNZr-1; fluorocarbon resin was purchased from Daikin Fluorochemical Co., Ltd., product model GK-570; the defoamer was BYK-9920; the leveling agent was BYK-361N, an acrylic copolymer leveling agent; the wetting agent was polyether-modified polydimethylsiloxane (purchased from BYK, Germany, model BYK333); the thickener was a nonionic polyurethane associative thickener (purchased from Nae Woi Korea., Ltd., model HIRESOL85); and the hydrophobic plasticizer was dioctyl phthalate. In the following examples and comparative examples, other chemical substances not explicitly stated were commercially obtained.

[0049] In the following examples and comparative examples: the solid content, open time, hardness, tear strength, tensile strength, and elongation at break were tested using the measurement methods described in GB / T 16777-2008, Test Methods for Building Waterproof Coatings; the water contact angle and water absorption were tested using the method described in GBT 30693-2014, Measurement of Contact Angle of Plastic Film with Water; the adhesion was tested using the test method described in ISO 4624; and the freezing test was conducted using the method described in GB 23446-2009, Spray Polyurea Waterproof Coatings: the coating was placed in water and placed in a -17°C freezer to freeze, and its adhesion to ice was tested.

[0050] Example 1

[0051] A polyasparagus protective material for freeze-thaw protection and beautification marking used in pumped storage power stations, the specific preparation method of which is as follows:

[0052] S1. Synthesis of Silane-Modified Nanoparticle Composition

[0053] Nano-silica and nano-zirconium dioxide were added to terephthalic acid in a mass ratio of 3:1 (the volume of terephthalic acid was as large as possible to ensure that the nano-silica and nano-zirconium dioxide could be suspended in the terephthalic acid after ultrasound), the temperature was raised to 45°C and ultrasound was performed for 50 minutes, and then the mixture was allowed to stand and centrifuged to obtain a precipitate;

[0054] The silane coupling agent was added to an ethanol-water solution with a volume ratio of 1:1, and the temperature was raised to 55° C. and kept under reflux for 3 hours. Then, the precipitate and the organotin esterification catalyst were added, and the temperature was raised to 173° C. and kept under reflux for 7 hours. After cooling to room temperature, the mixture was allowed to stand, centrifuged, washed once with anhydrous ethanol, washed twice with acetone, and finally dried under vacuum at 45° C. to obtain a silane-modified nanoparticle composition. The structural formula of the silane coupling agent is as follows:

[0055]

[0056] S2. Synthesis of Nanoparticle-Modified Polyaspartic Acid

[0057] Under nitrogen protection, 4,4'-diaminodicyclohexylmethane and diethyl maleate were mixed at 65% and 35% by mass, respectively, and 2% by mass of the silane-modified nanoparticle composition and 4.5% by mass of proline were added. The mixture was heated to 75°C while stirring, and then diethyl maleate was slowly added. After the addition was completed, the temperature was raised to 105°C and the reaction was carried out for 10 hours to obtain nanoparticle-modified polyaspartic acid ester;

[0058] S3. Preparation of polyisocyanate curing agent

[0059] Hexamethylene diisocyanate and p-phenylene diisocyanate are mixed in 60 wt% and 40 wt% by weight, respectively, and 2 wt% of the total weight of the silane-modified nanoparticle composition is added thereto, and the mixture is stirred to obtain the polyisocyanate curing agent;

[0060] S4. Synthesis of Polyasparagus Protective Materials

[0061] The method comprises the following steps: using a polyisocyanate curing agent as component A; mixing and grinding the nanoparticle-modified polyaspartic acid ester with a fluorocarbon resin, titanium dioxide, a defoamer, a wetting agent, a leveling agent, a thickener, and a hydrophobic plasticizer to obtain a component B, wherein the contents of the components in the component B are as follows: 55 wt% of the nanoparticle-modified polyaspartic acid ester, 25 wt% of the fluorocarbon resin, 6 wt% of a pigment, 6 wt% of an auxiliary agent, and 8 wt% of a hydrophobic plasticizer; and when using the component A and the component B, mixing and stirring the component B at a molar ratio of -NCO to -NH of 1.07, performing polymerization at room temperature, and spraying the mixture into a mold.

[0062] Example 2

[0063] Compared with Example 1, the terephthalic acid in S1 was changed to isophthalic acid, and the p-phenylene diisocyanate in S3 was changed to isophenylene diisocyanate. The rest were the same as in Example 1.

[0064] Example 3

[0065] Compared with Example 1, the terephthalic acid in S1 was changed to 3,3'4,4'-biphenyltetracarboxylic acid, and the p-phenylene diisocyanate in S3 was changed to biphenyl-4,4'-diisocyanate.

[0066] Example 4

[0067] Compared with Example 1, the terephthalic acid in S1 was changed to terphenyl dicarboxylic acid. The rest was the same as Example 1.

[0068] Example 5

[0069] Compared with Example 1, the terephthalic acid in S1 was adjusted to 1,2,4,5-tetrakis(4-carboxyphenyl)benzene. The rest was the same as Example 1.

[0070] Example 6

[0071] Compared with Example 1, the terephthalic acid in S1 was changed to 3,3',5,5'-azobenzenetetracarboxylic acid. The rest were the same as in Example 1.

[0072] Example 7

[0073] Compared with Example 1, the terephthalic acid in S1 was adjusted to diphenylacetylene-3,3',5,5'-tetracarboxylic acid. The rest was the same as Example 1.

[0074] Compared with Example 1, step S1 was not performed, that is, nano-silicon dioxide and nano-zirconium dioxide were simply used as the nanoparticle composition in a mass ratio of 3:1 without any modification.

[0075] Comparative Example 2

[0076] Compared with Example 1, the silane-modified nanoparticle composition is added at one time. Specifically, the silane-modified nanoparticle composition in step S3 is added together with the silane-modified nanoparticle composition in step S2. The rest is the same as in Example 1.

[0077] Comparative Example 3

[0078] Compared with Example 1, the silane-modified nanoparticle composition is added at one time. Specifically, the silane-modified nanoparticle composition in step S2 is added in step S3. The rest is the same as in Example 1.

[0079] Comparative Example 4

[0080] Compared with Example 1, the silane coupling agent was adjusted to KH-550. The rest were the same as Example 1.

[0081] Comparative Example 5

[0082] Compared with Example 1, step S3 does not contain p-phenylene diisocyanate. The rest are the same as Example 1.

[0083] Comparative Example 6

[0084] Compared with Example 1, hexamethylene diisocyanate is not contained in step 3. The rest are the same as Example 1.

[0085] The products obtained from the above embodiments and comparative examples were subjected to various performance tests. The solid content of each embodiment was greater than 83%, the surface dry time was less than 1.5 hours, and the hardness was greater than 80 Shore A. The remaining properties are shown in Table 1 below:

[0086] Table 1

[0087]

[0088] As shown in Table 1:

[0089] (1) From the comparison between Comparative Example 1 and Example 1, it can be seen that the modified nanoparticle composition using the specified silane has a significantly larger contact angle with water and a significantly lower water absorption rate than the unmodified polyasparagus protective material, while the mechanical properties such as adhesion, tensile strength, elongation at break, and tear strength are slightly improved, but the magnitude is not particularly large.

[0090] (2) Comparison between Comparative Examples 2 and 3 and Example 1 shows that when the nanoparticle composition is modified with silane, but not added separately but all at once, whether added to component A or component B, the contact angle of the resulting polyasparagine protective material with water increases and the water absorption rate decreases, but the amplitude of the change is relatively small; the same is true for the mechanical properties.

[0091] (3) From the comparison between Comparative Example 4 and Example 1, it can be seen that: when the silane coupling agent KH550 is used, although the waterproof performance of the obtained polyasparagine protective material is improved, the degree of improvement is far less than that of the silane coupling agent specified in the present invention, and the mechanical properties of the material are also inferior to those of the present invention; it is obvious that the silane coupling agent specified in the present invention not only improves the dispersion uniformity of the modified nanoparticle composition in the system and promotes its effective hydrophobic effect, but also plays a role in improving the various mechanical properties of the polyasparagine protective material;

[0092] (4) From the comparison of Comparative Examples 5 and 6 with Example 1, it can be seen that when hexamethylene diisocyanate or p-phenylene diisocyanate is used alone, the obtained polytianmen protective material has relatively good waterproof properties, but relatively poor mechanical properties;

[0093] (5) Compared with Example 1, when the ice layer adhesion test was performed in each comparative example, the ice could not fall off automatically, indicating that the ice pull-out resistance was poor and the freeze-thaw resistance was poor;

[0094] (6) From the comparison between Examples 4 to 7 and Example 1, it can be seen that when the aromatic polyacids are terphenyl dicarboxylic acid, 1,2,4,5-tetrakis (4-carboxyphenyl) benzene, 3,3',5,5'-azobenzene tetracarboxylic acid, and diphenylacetylene-3,3',5,5'-tetracarboxylic acid, the resulting products have different degrees of improvement in both waterproof and mechanical properties compared with terephthalic acid. The reason for this may be that aromatic polyacids with three or more benzene rings and aromatic polyelements with two benzene rings containing azo and acetylene groups can form good conjugation with the nitrogen-oxygen six-membered rings in each structural unit of polyaspartic acid, thereby improving the reaction activity and the stability of the product, which is ultimately reflected in the further improvement of its waterproof and mechanical properties. To further investigate the binding strength between the polytianmen protective materials obtained in Comparative Examples 1-4 and the ice layer, ice adhesion tests were conducted on Example 1 and Comparative Examples 1-4 at a temperature of -17°C and a humidity of 80%, according to the method described in HG / T 5367.5-2022, Testing of Anti-icing Coatings for Rail Transit Vehicles. The specific test results are shown in Table 2. Note: Ice adhesion refers to the force required to remove ice after it has formed.

[0095] Table 2

[0096] project temperature humidity% Ice power (N) Example 1 -17℃ 80 0 Comparative Example 1 -17℃ 80 98 Comparative Example 2 -17℃ 80 73 Comparative Example 3 -17℃ 80 76 Comparative Example 4 -17℃ 80 32

[0097] As shown in Table 2, the ice-grabbing forces of Comparative Example 1 and Example 1 show that when the nanoparticle composition is not silane-modified, the ice-grabbing force required is 98 N. Upon modification, the ice layer automatically falls off. The ice-grabbing forces of Comparative Examples 2 and 3, compared to Example 1, show that when the nanoparticle composition is silane-modified but not added separately but all at once, whether added to Component A or Component B, the ice-grabbing force, while lower than that of the unmodified composition, is still relatively high. The ice-grabbing forces of Comparative Example 4 and Example 1 show that when KH550 is used as the silane coupling agent instead of the silane coupling agent specified in this application, the ice-grabbing force, although significantly lower than that of the unmodified composition, is still 32 N. Clearly, to achieve good freeze-thaw resistance, the nanoparticle composition must be modified with the silane coupling agent specified in this application and added twice, separately, to Component A and Component B. All three are essential.

[0098] In addition, Example 1, Comparative Example 5, and Comparative Example 6 were subjected to a weathering aging test (according to GB / T16777-2008). During the test, a xenon lamp artificial weathering test was performed for 1500 hours. The specific test results are shown in Table 3:

[0099] Table 3

[0100]

[0101]

[0102] As shown in Table 3: When the polyisocyanate curing agent only uses p-phenylene diisocyanate, the obtained polyaspartic protective material has relatively good weather resistance, but low tensile strength; when the polyisocyanate curing agent only uses hexamethylene diisocyanate, although the tensile strength is relatively high, the weather resistance is poor; when hexamethylene diisocyanate and p-phenylene diisocyanate are mixed according to mass percentages of 60wt% and 40wt% respectively, the obtained polyaspartic protective material has both good tensile strength and weather resistance.

[0103] A pumped storage power station in Jilin Province was built 11 years ago. When it was first built, a concrete protective mortar was laid on the water-facing surface of the dam, and then a PVC modified asphalt layer was melted on the outside of the mortar layer. After long-term use, the mortar protective layer has partially fallen off and broken, and the PVC modified asphalt layer has seriously aged. The polytianmen protective material prepared in Example 1 of the present invention is used to spray the water-facing surface of the dam. Before spraying, the original mortar protective layer and the PVC modified asphalt layer are removed and milled to expose the new aggregate layer of concrete and its surface is relatively flat and smooth. Then, a mortar with a thickness greater than 3.5 cm is applied, and the polytianmen protective material obtained in Example 1 is sprayed on the surface of the mortar. Figure 1 The photo shown is before spraying. Figure 2 The photo shown is after spraying: the coating surface is evenly coated and has high flatness, without any defects such as bubbles, cracks, holes, honeycomb and so on. Figure 3 The photo shown is after three winters. The spray coating showed no ice pull-out phenomenon, and the coating surface had no peeling, scratches, cracks, pinholes, or wrinkles.

[0104] In summary: the anti-freeze-thaw beautification marking polytianmen protective material proposed by the present invention for use in pumped storage power stations has strong adhesion to the sprayed surface, is waterproof and anti-seepage, and is not prone to damage or breakage. More importantly, it has almost no adhesion to ice, has good anti-freeze-thaw ability, and is suitable for use in extremely cold environments with low temperatures.

[0105] Although embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are illustrative and are not to be construed as limiting the present invention. Those skilled in the art may alter, modify, replace, and modify the above embodiments within the scope of the present invention. Furthermore, those skilled in the art may combine and incorporate the various embodiments or examples described in this specification, as well as features thereof, without conflicting requirements.

Claims

1. A method for preparing a freeze-thaw-proof beautification marking polyasparagus protective material for use in pumped storage power stations, characterized by: The following operations are included: S1. Synthesis of Silane-Modified Nanoparticle Composition The hydrophobic nanoparticle composition is added to an aromatic polyacid, heated to 40-50° C. and ultrasonicated for more than 45 minutes, then allowed to stand and centrifuged to obtain a precipitate; The silane coupling agent is added to an ethanol aqueous solution, heated to 50-60° C. and kept refluxed for 2-4 hours, then the precipitate and the organotin esterification catalyst are added, the temperature is raised to 170-175° C. and kept refluxed for 6-8 hours, cooled to room temperature, allowed to stand, centrifuged, washed with anhydrous ethanol and acetone in sequence, and finally vacuum dried to obtain a silane-modified nanoparticle composition; the structural formula of the silane coupling agent is as follows: ； S2. Synthesis of Nanoparticle-Modified Polyaspartic Acid Under nitrogen protection, the silane-modified nanoparticle composition, proline, and 4,4'-diaminodicyclohexylmethane were mixed, and the temperature was raised to 70-80°C while stirring. Then, diethyl maleate was slowly added. After the addition was completed, the temperature was raised to 100-110°C, and the reaction was carried out for at least 10 hours to obtain nanoparticle-modified polyaspartic acid ester; S3. Preparation of polyisocyanate curing agent Mixing an aliphatic polyisocyanate curing agent, at least one aromatic polyisocyanate curing agent, and the silane-modified nanoparticle composition and stirring them uniformly to obtain the polyisocyanate curing agent; S4. Synthesis of Polyasparagus Protective Materials The polyisocyanate curing agent is used as component A; the nanoparticle-modified polyaspartic acid ester is mixed with a fluorocarbon resin, a pigment, an additive, and a hydrophobic plasticizer, and then ground to obtain component B; when used, components A and B are mixed and stirred evenly, polymerized at room temperature, and sprayed for molding.

2. The method for preparing the anti-freeze-thaw beautification marking polyasparagus protective material for use in pumped storage power stations according to claim 1, characterized in that: In S1, The aromatic polyacid is specifically selected from at least one of terephthalic acid, isophthalic acid, 3,5-dicarboxychlorobenzene, 3,3',5,5'-biphenyltetracarboxylic acid, 3,3',5,5'-azobenzenetetracarboxylic acid, 3,3'4,4'-biphenyltetracarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylacetylene-3,3',5,5'-tetracarboxylic acid, triphenylmethanetricarboxylic acid, terphenyldicarboxylic acid, [1,1':3',1''-terphenyl]-3,4'',5-tricarboxylic acid, 1,3,5-tris(4-carboxyphenyl)benzene, and 1,2,4,5-tetrakis(4-carboxyphenyl)benzene.

3. The method for preparing the anti-freeze-thaw beautification marking polyasparagus protective material for use in pumped storage power stations according to claim 1, characterized in that: In S3, the aliphatic polyisocyanate curing agent and the aromatic polyisocyanate curing agent are used as reaction substrate I, the content of the aliphatic polyisocyanate curing agent is 55-65wt%, and the addition amount of the silane-modified nanoparticle composition is 0.5-3wt% of the reaction substrate I.

4. The method for preparing the freeze-thaw-proof beautification-marked polyasparagus protective material for use in pumped storage power stations according to any one of claims 1 to 3, characterized in that: In S2, 4,4'-diaminodicyclohexylmethane and diethyl maleate are used as reaction substrate II, the addition amount of 4,4'-diaminodicyclohexylmethane is 60-70wt% of the reaction substrate II, the addition amount of the silane-modified nanoparticle composition is 0.5-3wt% of the reaction substrate II, and the addition amount of proline is 3-6wt% of the reaction substrate II.

5. The method for preparing the freeze-thaw-proof beautification-marked polyasparagus protective material for use in pumped-storage power stations according to any one of claims 1 to 3, characterized in that: The aliphatic polyisocyanate curing agent and the aromatic polyisocyanate curing agent are compounded in a mass ratio of 1.5:

1.

6. The method for preparing the freeze-thaw-proof beautification marking polyasparagus protective material for use in pumped storage power stations according to claim 5, characterized in that: In S3, the aliphatic polyisocyanate curing agent is hexamethylene diisocyanate, and the aromatic polyisocyanate curing agent is selected from at least one of p-phenylene diisocyanate, m-phenylene diisocyanate, toluene-2,6-diisocyanate, diphenylmethane-4,4'-diisocyanate, naphthalene-1,5-diisocyanate, biphenyl-4,4'-diisocyanate, 3-methyldiphenylmethane-4,4'-diisocyanate, diphenyl ether diisocyanate, and triphenylmethane triisocyanate.

7. The method for preparing the freeze-thaw-proof beautification-marked polyasparagus protective material for use in pumped-storage power stations according to any one of claims 1 to 3, characterized in that: In S4, the molar ratio of -NCO in component A to -NH in component B is 1.06-1.

08.

8. The method for preparing the freeze-thaw-proof beautification-marked polyasparagus protective material for use in pumped storage power stations according to any one of claims 1 to 3, characterized in that: In S1, the hydrophobic nanoparticle composition is a composition of nano-silicon dioxide and nano-zirconium dioxide, and the mass ratio of nano-silicon dioxide to nano-zirconium dioxide is (1-5):1; the ethanol aqueous solution is an ethanol aqueous solution with a volume ratio of 1:1; After centrifugation, wash once with anhydrous ethanol and then twice with acetone, and the vacuum drying temperature shall not exceed 45°C.

9. The method for preparing the freeze-thaw-proof beautification-marked polyasparagus protective material for use in pumped storage power stations according to any one of claims 1 to 3, characterized in that: In S4, the fluorine content of the fluorocarbon resin is ≥26%, specifically selected from at least one of polytetrafluoroethylene and ethylene-tetrafluoroethylene copolymer; the pigment is at least one of titanium dioxide, barium dioxide, zinc dioxide, iron red, iron yellow, chrome yellow, iron black, carbon black and organic pigments; the auxiliary agent is at least one of a defoaming agent, a wetting agent, a leveling agent and a thickener; the content of each component in the B component is: 50-60wt% of the nanoparticle-modified polyaspartic acid ester, 20-30wt% of the fluorocarbon resin, 2-10wt% of the pigment, 0.1-10wt% of the auxiliary agent, and 3-10wt% of the hydrophobic plasticizer.

10. An anti-freeze-thaw beautification marking polyasparagus protective material prepared according to the preparation method according to any one of claims 1 to 9.

Images