A modified TB polymer, its preparation method and its application in an aluminum alloy surface coating

Abstract

The present invention belongs to the field of material technology, and particularly relates to a modified TB polymer, a preparation method thereof, and an application thereof in an aluminum alloy surface coating. The modified TB polymer prepared by the present invention has the structure shown in Formula I. When it is used as a toughening agent component in an aluminum alloy surface coating, it can provide a large number of hydrophilic hydroxyl or carboxyl groups that are easy to undergo activation reactions with the metal surface, improving the adhesion of the coating. At the same time, such groups can also improve the dispersion degree of the filler, making the coating more uniform, and can improve the stress effect of the coating, making the coating have better flexibility. In addition, by introducing the modified TB polymer into the coating, the prepared coating is green and environmentally friendly, has excellent salt spray resistance and chemical corrosion resistance, can adapt to complex marine environments, better protects metal materials, and extends their service life. I.

Description

Technical Field

[0001] The present invention belongs to the technical field of materials, and particularly relates to a modified TB polymer, a preparation method thereof, and an application thereof in an aluminum alloy surface coating. Background Art

[0002] Disclosing the information of this background art section is only intended to enhance the overall understanding of the present invention, and is not necessarily to be regarded as an admission or any form of implication that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] Aluminum alloys are widely used in the fields of aerospace, ships, automobiles, etc. due to their advantages such as light weight, high specific strength, excellent mechanical properties, and easy processing and forming. However, since most metal materials such as aluminum alloys are exposed to the natural environment for a long time, corrosion inevitably occurs. This corrosion will not only lead to a decrease or failure of the material strength, but also shorten the service life of the equipment, and may even cause major safety accidents and property losses.

[0004] In order to improve its anti-corrosion performance, coating a protective anti-corrosion coating on the surface of the aluminum alloy to prevent the corrosion of the substrate through functions such as shielding, corrosion inhibition, and cathodic protection is an effective method and measure. Traditional anti-corrosion coatings usually add chromate fillers to the coating to achieve passivation and slow-release effects, and these fillers rely on the blocking effect of chromate ions to protect the surface of the aluminum alloy. However, due to the serious harm of hexavalent chromium to the environment and human health, its use has been strictly restricted. In recent years, the research and application of environmentally friendly coating technologies without chromate fillers have gradually become the focus of the development of the anti-corrosion industry.

[0005] Anti-corrosion coatings mainly composed of epoxy resin have become the focus of attention due to their excellent weather resistance and anti-corrosion performance. However, due to the weak bonding force between the epoxy resin and the surface of the aluminum alloy, and the internal stress is easily generated due to uneven volume shrinkage during the curing process, cracks often occur in the coating, thereby affecting the stability of its anti-corrosion effect. Introducing inorganic nanomaterials into the epoxy resin can significantly enhance the barrier ability of the coating to water molecules, oxygen, and corrosion ions, thereby greatly improving its anti-corrosion performance. However, due to the high surface energy of the nanomaterials, agglomeration is likely to occur, resulting in uneven dispersion in the coating, thus affecting the overall performance of the coating. To solve the above problems, the key lies in optimizing the stress characteristics of the epoxy resin, improving the uniform dispersion of the nano-fillers therein, and enhancing its compatibility with the coating solution.

[0006] Tröger’s Base (hereinafter referred to as TB) polymers are a type of polymers with intrinsically microporous structures. Due to the unique twisted structure of their molecules and excellent mechanical, thermal, and chemical properties, they have attracted extensive attention and research in recent years in fields such as gas separation membranes, anion exchange membranes, and ultrafiltration membranes. TB polymers are prepared by the stepwise polymerization reaction of aromatic diamine monomers with dimethoxymethane in trifluoroacetic acid solution. Due to the presence of a large number of fused rings in the TB structure, the structure is highly rigid. Usually, the chemical structure and physical properties of TB polymers can be adjusted by the modification and design of the repeating units or a large number of side chain structures. Summary of the Invention

[0007] Aiming at the problems existing in the prior art, the present invention provides a modified TB polymer, a preparation method thereof, and its application in an aluminum alloy surface coating. By introducing the modified TB polymer into the composite coating on the aluminum alloy surface, the obtained coating is not only environmentally friendly but also has characteristics such as good flexibility and strong metal adhesion, which can meet the durability requirements of anti-corrosion coatings.

[0008] To achieve the above objectives, the present invention adopts the following technical solutions:

[0009] In the first aspect of the present invention, a modified TB polymer is provided, and the modified TB polymer has the structure shown in Formula I:

[0010] Formula I;

[0011] Among them, R is selected from , , , , and one or more of them.

[0012] In the second aspect of the present invention, a preparation method of the above-mentioned modified TB polymer is provided, specifically:

[0013] Mix the TB polymer with the halogenated compound RX and dissolve them in an organic solvent, carry out a heating reaction, then cool to room temperature, wash, and vacuum dry to obtain the modified TB polymer; among them, in the halogenated compound RX, R is selected from , , , , one of them; X is selected from one or more of fluorine, chlorine, bromine, and iodine.

[0014] Preferably, the synthesis reaction formula is as follows:

[0015]

[0016] Preferably, the halogenated compound RX is selected from one or more of 3-bromo-1,2-benzenediol, 4-bromobutyric acid, 5-bromo-2-methylpyridine, 3-bromopropylamine, and 4-bromopiperidine.

[0017] Preferably, the mass ratio of the halogenated compound RX to the TB polymer is 2-8:1.

[0018] Preferably, the temperature of the heating reaction is 20-80 °C, and the time is 6-48 h.

[0019] Preferably, the organic solvent is one of dichlorobenzene, chloroform, ether, and N-methylpyrrolidone.

[0020] Preferably, the mass ratio of the organic solvent to the TB polymer is 3-20:1.

[0021] Preferably, the specific synthesis process of the TB polymer is as follows: under an inert atmosphere, using 4,4'-diamino-3,3'-dimethylbiphenyl as a raw material and trifluoroacetic acid as a catalyst, reacting with paraformaldehyde in an organic solvent to obtain the TB polymer. The synthesis reaction formula is as follows:

[0022] 。

[0023] More preferably, the mass ratio of trifluoroacetic acid to 4,4'-diamino-3,3'-dimethylbiphenyl is 1:10-50; the mass ratio of the organic solvent to 4,4'-diamino-3,3'-dimethylbiphenyl is 3-5:1; the mass ratio of paraformaldehyde to 4,4'-diamino-3,3'-dimethylbiphenyl is 1.2-3:1; the pressure is normal pressure; the inert atmosphere is selected from one or more of argon and nitrogen.

[0024] More preferably, the organic solvent is selected from one or more of dimethylacetamide, methanol, chloroform, ether, and N-methylpyrrolidone.

[0025] More preferably, the temperature of the reaction is 0-5 °C, and the time is 3-72 h.

[0026] In the third aspect of the present invention, a wear-resistant and corrosion-resistant composite coating is provided, including the modified TB polymer described in the first aspect.

[0027] Preferably, the modified TB polymer is used as a toughening agent component in the wear-resistant and corrosion-resistant composite coating.

[0028] Preferably, the wear-resistant and corrosion-resistant composite coating further includes epoxy resin, inorganic filler, graphene, anti-settling agent, curing agent, leveling agent, organic solvent M, and organic solvent N.

[0029] Preferably, for the wear-resistant and corrosion-resistant composite coating, by weight, 15-45 parts of epoxy resin, 1-20 parts of modified TB polymer, 5-20 parts of inorganic filler, 15-40 parts of organic solvent M, 0.5-5 parts of graphene, 0.5-5 parts of anti-settling agent, 35-80 parts of curing agent, 2-10 parts of leveling agent, and 15-55 parts of organic solvent N.

[0030] Further preferably, the epoxy resin is selected from one or more of epoxy resin E44, epoxy resin E42, and epoxy resin E20; the inorganic filler is selected from one or more of barium sulfate powder, aluminum tripolyphosphate, kaolin powder, and mica powder; the organic solvent M is selected from one or more of xylene, butyl acetate, ethyl acetate, n-butanol, and isopropanol; the anti-settling agent is bentonite; the curing agent is selected from one or more of aliphatic polyamine curing agents, aliphatic amine adduct curing agents, and polyamide curing agents, preferably polyamide 650; the leveling agent is selected from one or more of polydimethylsiloxane and polyacrylate leveling agents; the organic solvent N is selected from one or more of ethylbenzene, ethyl acetate, n-butanol, and propylene glycol methyl ether acetate.

[0031] Further preferably, the particle sizes of the inorganic filler and graphene are 200-600 mesh, more preferably 300-400 mesh.

[0032] In the fourth aspect of the present invention, there is provided a preparation method of the wear-resistant and corrosion-resistant composite coating according to the third aspect, comprising the following steps:

[0033] S1. Sequentially add the modified TB polymer, inorganic filler, graphene, and anti-settling agent to the mixture of epoxy resin and organic solvent M and stir and react to obtain component A;

[0034] S2. Mix the curing agent, leveling agent, and organic solvent N and stir and react to obtain component B;

[0035] S3. Mix component A and component B to obtain the wear-resistant and corrosion-resistant composite coating.

[0036] Preferably, in step S1, the temperature of the stirring reaction is 15-30 °C, the time is 0.5-3 h, and the speed is 200-2000 r / min.

[0037] Preferably, in step S2, the temperature of the stirring reaction is 15-30 °C, the time is 0.5-3 h, and the speed is 200-2000 r / min.

[0038] Preferably, in step S3, the weight ratio of component A to component B is 100:30-80.

[0039] In a fifth aspect of the present invention, there is provided an application of the wear-resistant and corrosion-resistant composite coating described in the third aspect and / or the wear-resistant and corrosion-resistant composite coating prepared by the preparation method described in the fourth aspect in the field of anti-corrosion coatings.

[0040] The beneficial effects achieved by one or more of the above technical solutions of the present invention are as follows:

[0041] (1) In the present invention, a novel modified TB polymer toughening agent is added to the anti-corrosion coating. After the TB polymer is modified, a large number of alkane groups are grafted. The OH groups will undergo an activation reaction with metal substrates such as aluminum alloy, and then hydrogen desorption occurs, generating a dispersed interfacial part, significantly improving the adhesion between the epoxy resin coating and metal substrates such as aluminum alloy.

[0042] (2) A large number of OH groups present on the TB polymer prepared in the present invention can react with the surface of inorganic fillers such as graphene in the coating, enabling the inorganic fillers to be evenly distributed in the resin, avoiding the agglomeration problem of nano-inorganic fillers, strengthening the denseness of the composite coating, and effectively resisting the penetration of water molecules, oxygen, and electrolytes, thereby improving the anti-corrosion performance of the coating; at the same time, the nano-inorganic fillers replace conventional toxic fillers such as chromates, making the coating green and environmentally friendly.

[0043] (3) The added modified TB polymer toughening agent in the present invention can effectively improve problems such as cracks and microvoids caused by uneven internal stress during the curing process of the coating, increase the flexibility of the coating, effectively avoid erosion caused by corrosive substances entering the microvoids and microcracks of the coating through diffusion movement, improve the anti-corrosion performance of the coating, and extend the service life of the material. Description of the Drawings

[0044] The specification drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0045] Figure 1 It is the Fourier transform infrared spectrum diagram of the modified TB polymer prepared in Example 1 of the present invention;

[0046] Figure 2 It is the scanning electron microscope image (SEM) of the modified TB polymer prepared in Example 1 of the present invention;

[0047] Figure 3 It is the Fourier transform infrared spectrum diagram of the modified TB polymer prepared in Example 4 of the present invention;

[0048] Figure 4 It is the scanning electron microscope image of the modified TB polymer prepared in Example 4 of the present invention;

[0049] Figure 5 FT-IR spectrum of the TB polymer prepared in Comparative Example 1 of the present invention. Detailed Description of the Invention

[0050] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0051] The present invention will be further described in detail below in conjunction with specific embodiments. It should be noted that the specific embodiments are interpretations rather than limitations of the present invention.

[0052] Example 1: This example provides a modified TB polymer and its preparation method

[0053] (1) Preparation of TB polymer: Under an inert atmosphere, 15 g of 4,4'-diamino-3,3'-dimethylbiphenyl and 60 g of dimethylacetamide were mixed, stirred evenly at normal pressure at 5 °C, 45 g of paraformaldehyde was added, stirred, and 1 g of trifluoroacetic acid was added dropwise to the above mixture solution, and the reaction was continued for 12 h to obtain the TB polymer.

[0054] (2) Preparation of modified TB polymer: 10 g of the TB polymer prepared in step (1) was added to 50 g of chloroform, and 30 g of 3-bromo-1,2-benzenediol was added, and the reaction was carried out at 20 °C for 10 h to obtain a modified TB polymer toughener.

[0055] Figure 1 FT-IR spectrum of the modified TB polymer in the wear-resistant and corrosion-resistant composite coating for aluminum alloy surface in this example; it can be confirmed that the structural formula of the Tröger’s Base polymer prepared in the present invention is:

[0056]

[0057] As Figure 1 can be seen, the FT-IR spectrum shows that the infrared spectrum of the modified TB polymer is basically similar to that of the TB polymer ( Figure 5 ), but a characteristic absorption peak of the -OH group appears at 3020 cm -1 , and a characteristic absorption peak of C-N -1 representing quaternary ammonium salt appears at 1425 cm + , indicating that 3-bromo-1,2-benzenediol has been successfully grafted onto the TB polymer.

[0058] As Figure 2It can be seen that the scanning electron microscope image shows that the modified TB polymer prepared in this example is in the form of slender fibers. After adding it to the coating, the tear resistance and stress-strain resistance of the coating can be further enhanced, and the corrosion resistance of the coating can be improved.

[0059] Example 2: This example provides a modified TB polymer and a preparation method thereof

[0060] (1) Preparation of TB polymer: Under an inert atmosphere, 30 g of 4,4'-diamino-3,3'-dimethylbiphenyl and 90 g of chloroform were mixed, stirred evenly at normal pressure at 5 °C, then 36 g of paraformaldehyde was added, stirred, and 3 g of trifluoroacetic acid was added dropwise to the above mixture solution, and the reaction was continued for 12 h to obtain the TB polymer.

[0061] (2) Preparation of modified TB polymer: 10 g of the TB polymer prepared in step (1) was added to 30 g of chloroform, 20 g of 5-bromo-2-methylpyridine was added, and the reaction was carried out at 60 °C for 24 h to obtain a modified TB polymer toughening agent.

[0062] Data characterization: Peaks appearing in the range of 1600~1650 cm -1 and 1450 - 1500 cm -1 can represent the characteristic absorption peaks caused by the vibration of the six-membered ring skeleton in the piperidine molecule, indicating that the group with piperidine is grafted onto the TB polymer, and it can be confirmed that the structural formula of the Tröger’s Base polymer prepared in this example is:

[0063]

[0064] Example 3: This example provides a modified TB polymer and a preparation method thereof

[0065] (1) Preparation of TB polymer: Under an inert atmosphere, 30 g of 4,4'-diamino-3,3'-dimethylbiphenyl and 100 g of N-methylpyrrolidone were mixed, stirred evenly at normal pressure at 0 °C, then 60 g of paraformaldehyde was added, stirred, and 1 g of trifluoroacetic acid was added dropwise to the above mixture solution, and the reaction was continued for 6 h to obtain the TB polymer.

[0066] (2) Preparation of modified TB polymer: 10 g of the TB polymer prepared in step (1) was added to 30 g of N-methylpyrrolidone, 50 g of 3-bromopropylamine was added, and the reaction was carried out at 30 °C for 48 h to obtain a modified TB polymer toughening agent.

[0067] Data characterization: The doublet appearing at 3400~3200 cm -1 can represent -NH 2The appearance of characteristic absorption peaks indicates that an alkane with an amino group is grafted onto the TB polymer, and it can be confirmed that the structural formula of the Tröger’s Base polymer prepared in this example is:

[0068]

[0069] Example 4: This example provides a modified TB polymer and its preparation method

[0070] (1) Preparation of TB polymer: Under an inert atmosphere, 50 g of 4,4'-diamino-3,3'-dimethylbiphenyl and 150 g of chloroform were mixed, stirred evenly at normal pressure at 0 °C, then 75 g of paraformaldehyde was added, stirred, and 1 g of trifluoroacetic acid was added dropwise to the above mixture solution, and the reaction continued for 72 h to obtain the TB polymer.

[0071] (2) Preparation of modified TB polymer: 10 g of the TB polymer prepared in step (1) was added to 40 g of chloroform, and 80 g of 4-bromobutyric acid was added, and the reaction was carried out at 30 °C for 24 h to obtain a modified TB polymer toughener.

[0072] Figure 3 is the Fourier transform infrared spectrum of the modified TB polymer in the wear-resistant and corrosion-resistant composite coating for the aluminum alloy surface in this example; it can be confirmed that the structural formula of the Tröger’s Base polymer prepared in this example is:

[0073]

[0074] From Figure 3 it can be seen that the Fourier transform infrared spectrum shows that a characteristic absorption peak representing C=O appears at 1746 cm -1 −1, combined with the characteristic absorption peak of the -OH group appearing at 3020 cm -1 −1, it shows that the carboxyl group has been successfully grafted onto the TB polymer, realizing the modification of the TB polymer.

[0075] From Figure 4 it can be seen that the scanning electron microscope image shows that the modified TB polymer is in the shape of slender fibers. After adding it to the coating, the tear resistance and stress-strain ability of the coating can be further enhanced, and the corrosion resistance of the coating can be improved.

[0076] Example 5: This example provides a modified TB polymer and its preparation method

[0077] (1) Preparation of TB polymer: Under an inert atmosphere, 10 g of 4,4'-diamino-3,3'-dimethylbiphenyl and 50 g of chloroform were mixed, stirred evenly at normal pressure at 0 °C, then 20 g of paraformaldehyde was added, stirred, and 1 g of trifluoroacetic acid was added dropwise to the above mixture solution, and the reaction was continued for 24 h to obtain the TB polymer.

[0078] (2) Preparation of modified TB polymer: 10 g of the TB polymer prepared in step (1) was added to 30 g of dichlorobenzene, and 30 g of 4-bromopiperidine was added, and the reaction was carried out at 30 °C for 8 h to obtain a modified TB polymer toughening agent.

[0079] Data characterization: The peaks appearing in the range of 1600~1650 cm -1 and 1450 - 1500 cm -1 can represent the characteristic absorption peaks caused by the vibration of the six-membered ring skeleton in the piperidine molecule, indicating that the group with piperidine is grafted onto the TB polymer. It can be confirmed that the structural formula of the Tröger’s Base polymer prepared in this example is:

[0080]

[0081] Comparative example 1:

[0082] The difference between this comparative example and Example 1 is that only the preparation in step (1) was carried out, and the modification operation in step (2) was not carried out.

[0083] Data characterization: As Figure 5 shown, a characteristic absorption peak of C=C representing the benzene ring appeared at 1461 cm -1 , a characteristic absorption peak of C-N bond appeared at 1664 cm -1 , characteristic absorption peaks of C-N-C bond appeared at 1089 cm -1 and 800 cm -1 . The appearance of these three peaks indicates the existence of a tertiary amine structure in TB. A characteristic absorption peak of -CH -1 appeared at 2928 cm 3 . The appearance of the above characteristic peaks indicates that the TB polymer has been successfully synthesized.

[0084] Application example 1: This application example provides a wear-resistant and corrosion-resistant composite coating for the surface of aluminum alloy and its preparation method. The specific steps are as follows:

[0085] The wear-resistant and anti-corrosion composite coating prepared in this embodiment includes, by weight: 30 parts of epoxy resin, 10 parts of modified TB polymer toughening agent prepared in Example 1, 10 parts of ethyl acetate, 20 parts of aluminum tripolyphosphate, 2 parts of graphene, 1.5 parts of diatomaceous earth, 35 parts of polyamide 650, 30 parts of n-butanol, and 5 parts of polydimethylsiloxane.

[0086] The preparation method is specifically as follows:

[0087] (1) Add 10 parts by weight of modified TB polymer toughening agent and 40 parts by weight of ethyl acetate to 30 parts by weight of epoxy resin, stir for 1 h at a reaction temperature of 20°C and a stirring speed of 200 r / min. Then add 20 parts by weight of aluminum tripolyphosphate, 2 parts by weight of graphene and 1.5 parts by weight of diatomaceous earth, stir for 2 h at a reaction temperature of 20°C and a stirring speed of 800 r / min to obtain component A;

[0088] (2) Add 30 parts by weight of n-butanol to 35 parts by weight of polyamide 650, stir evenly, then add 5 parts by weight of polydimethylsiloxane, stir at a reaction temperature of 20°C for 1 h at a stirring speed of 300 r / min to obtain component B;

[0089] (3) 100 parts by weight of component A and 70 parts by weight of component B are mixed and coated on the surface of the aluminum alloy metal after sandblasting. After curing for 24 hours, a wear-resistant and anti-corrosion composite coating for the aluminum alloy surface is obtained.

[0090] Application Example 2: This application example provides a wear-resistant and anti-corrosion composite coating for aluminum alloy surface and a preparation method thereof. The specific steps are as follows:

[0091] The wear-resistant and anti-corrosion composite coating prepared in this embodiment includes, by weight: 40 parts of epoxy resin, 10 parts of the modified TB polymer toughening agent prepared in Example 2, 40 parts of ethyl acetate, 15 parts of aluminum tripolyphosphate, 2 parts of graphene, 1 part of diatomaceous earth, 40 parts of polyamide 650, 30 parts of n-butanol, and 5 parts of polydimethylsiloxane.

[0092] The preparation method is as follows: (1) adding 10 parts by weight of a modified TB polymer toughening agent and 40 parts by weight of ethyl acetate to 40 parts by weight of epoxy resin, stirring for 1 h at a reaction temperature of 20°C and a stirring speed of 200 r / min. Then adding 15 parts by weight of aluminum tripolyphosphate, 2 parts by weight of graphene and 1 part by weight of diatomaceous earth, stirring for 2 h at a reaction temperature of 20°C and a stirring speed of 800 r / min to obtain component A;

[0093] (2) Add 30 parts by weight of n-butanol to 40 parts by weight of polyamide 650. After stirring evenly, add 5 parts by weight of polydimethylsiloxane. At a reaction temperature of 20 °C, stir for 1 h at a stirring speed of 300 r / min to obtain Component B;

[0094] (3) Mix 100 parts by weight of Component A and 70 parts by weight of Component B, and apply them on the surface of sandblasted aluminum alloy metal. After curing for 24 h, a wear-resistant and corrosion-resistant composite coating for aluminum alloy surface is obtained.

[0095] Application Example 3: This application example provides a wear-resistant and corrosion-resistant composite coating for aluminum alloy surface and its preparation method. The specific steps refer to Application Example 1. The difference from Application Example 1 is that in step (1) of this embodiment, the modified TB polymer toughening agent prepared in Example 3 is added, and the contents of other components and the preparation method are the same as those in Application Example 1.

[0096] Application Example 4: This application example provides a wear-resistant and corrosion-resistant composite coating for aluminum alloy surface and its preparation method. The specific steps refer to Application Example 1. The difference from Application Example 1 is that in step (1) of this embodiment, the modified TB polymer toughening agent prepared in Example 4 is added, and the contents of other components and the preparation method are the same as those in Application Example 1.

[0097] Application Example 5: This application example provides a wear-resistant and corrosion-resistant composite coating for aluminum alloy surface and its preparation method. The specific steps refer to Application Example 2. The difference from Application Example 2 is that in step (1) of this embodiment, the modified TB polymer toughening agent prepared in Example 5 is added, and the contents of other components and the preparation method are the same as those in Application Example 1.

[0098] Application Example 6: This application example provides a wear-resistant and corrosion-resistant composite coating for aluminum alloy surface and its preparation method. The specific steps refer to Application Example 1. The difference from Application Example 1 is that in step (1) of this embodiment, the TB polymer toughening agent prepared in Comparative Example 1 is added, and the contents of other components and the preparation method are the same as those in Application Example 1.

[0099] Application Example 7: This application example provides a wear-resistant and corrosion-resistant composite coating for aluminum alloy surface and its preparation method. The specific steps refer to Application Example 1. The difference from Application Example 1 is that in step (1) of this application example, the modified TB polymer toughening agent is not added, and the contents of other components and the preparation method are the same as those in Application Example 1.

[0100] Test Example 1: This test example is to conduct salt spray resistance test and mechanical property test on the wear-resistant and corrosion-resistant composite coatings prepared in Application Examples 1-7 in a salt spray test chamber.

[0101] Among them, the corrosion resistance test was determined in accordance with GB / T 1771-2007 "Determination of Resistance to Neutral Salt Spray of Paints and Varnishes"; the adhesion test was determined in accordance with GB / T 5210-2006 "Pull-off Adhesion Test for Paints and Varnishes"; the test of the pencil hardness of the paint film was determined in accordance with GB / T 6739-2006 "Determination of Film Hardness of Colored Paints and Coatings by the Pencil Method"; the abrasion resistance was tested in accordance with GB / T 1768-2006 "Method for Determination of Abrasion Resistance of Paint Films"; the impact resistance was tested in accordance with GB / T 1732-93 "Method for Determination of Impact Resistance of Paint Films".

[0102] The test results are shown in Table 1 and Table 2 as follows:

[0103] Table 1 Salt Spray Resistance Test of Wear-Resistant and Corrosion-Resistant Composite Coating

[0104]

[0105] Table 2 Mechanical Property Test of Wear-Resistant and Corrosion-Resistant Composite Coating

[0106]

[0107] It can be seen from the test results in Table 1 and Table 2 that compared with Application Example 6, the modified TB polymer toughening agent is added in Application Example 1 of the present invention, and the salt spray resistance and mechanical properties of the obtained coating are both improved; compared with Application Example 7 without adding the modified TB polymer toughening agent, the modified toughening agent added in Application Example 1 of the present invention can better carry out surface reaction with the hydroxyl groups on the surface of the inorganic filler and the metal base by using its hydrophilic groups, significantly improving the adhesion of the coating, and the salt spray resistance and mechanical properties of the obtained coating are better.

[0108] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wear-resistant and anti-corrosion composite coating, characterized in that: The wear-resistant and anti-corrosion composite coating comprises, by weight, 15 to 45 parts of epoxy resin, 1 to 20 parts of modified TB polymer, 5 to 20 parts of inorganic filler, 15 to 40 parts of organic solvent M, 0.5 to 5 parts of graphene, 0.5 to 5 parts of anti-settling agent, 35 to 80 parts of curing agent, 2 to 10 parts of leveling agent, and 15 to 55 parts of organic solvent N; Wherein, the modified TB polymer has a structure shown in Formula I: Formula I; Among them, R is selected from , , , and One or more of the following; The inorganic filler is selected from one or more of barium sulfate powder, aluminum tripolyphosphate, kaolin powder, and mica powder.

2. The wear-resistant and anti-corrosion composite coating according to claim 1, characterized in that: The preparation method of the modified TB polymer is specifically as follows: the TB polymer and the halogenated compound RX are mixed and dissolved in an organic solvent, heated for reaction, then cooled to room temperature, washed, and vacuum dried to obtain the modified TB polymer; Wherein, R in the halogenated compound RX is selected from , , , , one of; X is bromine; the halogenated compound RX is selected from one or more of 3-bromo-1,2-diphenol, 4-bromobutyric acid, 5-bromo-2-methylpyridine, 3-bromopropylamine, and 4-bromopiperidine; the mass ratio of the halogenated compound RX to the TB polymer is 2-8:1; the organic solvent is one of dichlorobenzene, chloroform, ether, and N-methylpyrrolidone; the temperature of the heating reaction is 20-80°C, and the time is 6-48 h; the mass ratio of the organic solvent to the TB polymer is 3-20:

1.

3. The wear-resistant and anti-corrosion composite coating according to claim 2, characterized in that: The specific synthesis process of the TB polymer is: under an inert atmosphere, using 4,4'-diamino-3,3'-dimethylbiphenyl as a raw material and trifluoroacetic acid as a catalyst, reacting with paraformaldehyde in an organic solvent to obtain the TB polymer; The mass ratio of trifluoroacetic acid to 4,4'-diamino-3,3'-dimethylbiphenyl is 1:10-50; the mass ratio of the organic solvent to 4,4'-diamino-3,3'-dimethylbiphenyl is 3-5:1; the mass ratio of paraformaldehyde to 4,4'-diamino-3,3'-dimethylbiphenyl is 1.2-3:1; the reaction pressure is normal pressure; the inert atmosphere is selected from one or more of argon and nitrogen; the organic solvent is selected from one or more of dimethylacetamide, methanol, chloroform, ether, and N-methylpyrrolidone; the reaction temperature is 0-5°C and the reaction time is 3-72 h.

4. The wear-resistant and anti-corrosion composite coating according to claim 1, characterized in that: The epoxy resin is selected from one or more of epoxy resin E44, epoxy resin E42, and epoxy resin E20; the organic solvent M is selected from one or more of xylene, butyl acetate, ethyl acetate, n-butanol, and isopropanol; the anti-settling agent is bentonite; the curing agent is selected from one or more of aliphatic polyamine curing agents, aliphatic amine adduct curing agents, and polyamide curing agents; the leveling agent is selected from one or more of polydimethylsiloxane and polyacrylate leveling agents; the organic solvent N is selected from one or more of ethylbenzene, ethyl acetate, n-butanol, and propylene glycol methyl ether acetate.

5. A method for preparing the wear-resistant and corrosion-resistant composite coating according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1, adding modified TB polymer, inorganic filler, graphene, and anti-settling agent to a mixture of epoxy resin and organic solvent M in sequence, stirring and reacting, to obtain component A; S2, mixing the curing agent, the leveling agent and the organic solvent N and stirring to react to obtain component B; S3. Mix component A and component B to obtain a wear-resistant and anti-corrosion composite coating.

6. The method for preparing the wear-resistant and corrosion-resistant composite coating according to claim 5, characterized in that: In step S1, the stirring reaction temperature is 15-30°C, the time is 0.5-3 h, and the speed is 200-2000 r / min; In step S2, the stirring reaction temperature is 15-30°C, the time is 0.5-3 h, and the speed is 200-2000 r / min; In step S3, the weight ratio of component A to component B is 100:30-80.

7. Use of the wear-resistant and anti-corrosion composite coating according to any one of claims 1 to 4 in the field of anti-corrosion coatings.

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