Corrosion-resistant and wear-resistant functional gradient coating and preparation method thereof

Abstract

The invention discloses a corrosion-resistant and wear-resistant functional gradient coating and a preparation method thereof, and belongs to the technical field of paints.The corrosion-resistant and wear-resistant functional gradient coating comprises a component A1, a component A2 and a component B, the component A1 is prepared from the following components in parts by weight: 10 parts of 4-hydroxybutyl vinyl ether, 60 to 80 parts of water-based hydroxy acrylic resin, 10 to 25 parts of dihydroxy polydimethylsiloxane, 60 to 140 parts of water and 10 to 40 parts of first modified filler; the component A2 is prepared from the following components in parts by weight: 5 parts of pentaerythritol, 5 to 15 parts of trihydroxybenzoic acid, 60 to 80 parts of water-based hydroxy acrylic resin, 60 to 140 parts of water and 15 to 50 parts of second modified filler; and the component B comprises an isocyanate curing agent. A coating formed by the corrosion-resistant and wear-resistant functional gradient paint has good corrosion resistance and wear resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to a corrosion-resistant and wear-resistant functional gradient coating and a preparation method thereof. Background Art

[0002] Corrosion of metal equipment is very common and causes a lot of economic losses every year. Coatings have a wide range of uses. For example, applying coatings to the surface of metal equipment not only serves as a decoration, but also provides good protection for metal equipment. It can slow down the corrosion and wear of metal equipment, thereby extending the service life of metal equipment. In addition, applying coatings to the surface of wooden furniture can also protect wooden furniture and extend its service life.

[0003] In the prior art, polyurethane coatings are applied on the surface of metal equipment to improve the corrosion resistance and wear resistance of the metal equipment, but the corrosion resistance and wear resistance are often not taken into account at the same time.

[0004] Therefore, it is urgent to provide a new coating that can have good corrosion resistance and wear resistance at the same time. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention provides a corrosion-resistant and wear-resistant functional gradient coating and a preparation method thereof. The coating formed by the functional gradient coating of the present invention has good corrosion resistance and wear resistance at the same time.

[0006] A first aspect of the present invention provides a corrosion-resistant and wear-resistant functional gradient coating.

[0007] A corrosion-resistant and wear-resistant functional gradient coating, comprising an A1 component, an A2 component, and a B component; The A1 component comprises, by weight: 10 parts of 4-hydroxybutyl vinyl ether, 60-80 parts of water-based hydroxylated acrylic resin, 10-25 parts of dihydroxy polydimethylsiloxane, 60-140 parts of water and 10-40 parts of the first modified filler; The A2 component comprises, by weight: 5 parts of pentaerythritol, 5-15 parts of trihydroxybenzoic acid, 60-80 parts of water-based hydroxy acrylic resin, 60-140 parts of water and 15-50 parts of a second modified filler; The B component includes: an isocyanate curing agent; The preparation process of the first modified filler is: mixing nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, a silane coupling agent, and a solvent, and then adding polyethylene glycol for ultrasonic dispersion to obtain the first modified filler; The preparation process of the second modified filler is: mixing nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent and solvent, and then adding polyethylene glycol for ultrasonic dispersion to obtain the second modified filler.

[0008] When the corrosion-resistant and wear-resistant functional gradient coating of the present invention is used, component A1 is mixed with component B, and coated on a substrate (the substrate may be a metal, such as iron, aluminum, alloy, etc.) to form a first functional layer, and then component A2 is mixed with component B, and coated on the first functional layer to form a second functional layer, and then cured to form a corrosion-resistant and wear-resistant functional gradient coating layer having good corrosion resistance and wear resistance.

[0009] The A1 component of the present invention utilizes the abundant hydroxyl groups in 4-hydroxybutyl vinyl ether, water-based hydroxy acrylic resin and dihydroxy polydimethylsiloxane to undergo a cross-linking and curing reaction with an isocyanate curing agent, and simultaneously introduces the skeleton structure of 4-hydroxybutyl vinyl ether, water-based hydroxy acrylic resin and dihydroxy polydimethylsiloxane, and cooperates with a modified filler, so that the modified filler is uniformly dispersed in a spatial network structure formed by the cross-linking reaction, and the effects of nano sodium silicate, nano titanium dioxide and nano manganese dioxide are fully utilized. Even if external acid and alkali corrosive substances penetrate into the second functional layer, it is extremely difficult to penetrate into the first functional layer.

[0010] The component A2 of the present invention utilizes the abundant hydroxyl groups of pentaerythritol, trihydroxybenzoic acid and water-based hydroxy acrylic resin to undergo a cross-linking and curing reaction with an isocyanate curing agent, and simultaneously introduces the skeleton structure of pentaerythritol, trihydroxybenzoic acid and water-based hydroxy acrylic resin, and cooperates with a modified filler, so that the modified filler is uniformly dispersed in a spatial network structure formed by the cross-linking reaction, and the corrosion resistance and wear resistance of nano sodium silicate, nano titanium dioxide, carbon nanotubes and nano molybdenum disulfide are fully exerted, especially the uniform dispersion of carbon nanotubes and nano molybdenum disulfide in the second functional layer, which significantly improves the wear resistance of the coating.

[0011] The present invention makes specific selection of components in the A1 component and the A2 component, so that they not only have good compatibility and high bonding strength, but also are conducive to fully exerting the anti-corrosion and wear-resistant functions of the A1 component and the A2 component, thereby solving the problem that it is difficult for coatings in the prior art to have both anti-corrosion and wear-resistant properties.

[0012] Preferably, in the first modified filler, the weight ratio of nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, silane coupling agent, solvent, and polyethylene glycol is 1: (1.5-3): (0.2-0.9): (1-5): (2-10): (10-30): (2-10); further preferably, the weight ratio is 1: (1.5-2.5): (0.3-0.9): (2-5): (3-10): (15-20): (3-8).

[0013] Preferably, in the second modified filler, the weight ratio of nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent, solvent, and polyethylene glycol is 1: (1.5-3): (0.1-1): (0.2-0.9): (1-5): (2-10): (10-30): (2-10); further preferably, the weight ratio is 1: (1.5-2.5): (0.2-0.8): (0.2-0.8): (2-5): (3-10): (15-30): (3-10).

[0014] Preferably, the weight ratio of the nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent, solvent, polyethylene glycol, and polydimethylsiloxane is 1: (1.5-3): (0.1-1): (0.2-0.9): (1-5): (2-10): (10-30): (2-10): (0.1-0.5).

[0015] Preferably, the B component also includes dibutyltin dilaurate. Adding a catalyst is beneficial to a more complete cross-linking reaction.

[0016] Preferably, in the component B, the weight ratio of isocyanate to dibutyltin dilaurate is 1:(0.05-0.4), and more preferably 1:(0.2-0.4).

[0017] Preferably, the weight ratio of the component A1 to the component B is 10:(0.5-3), more preferably 10:(1-2).

[0018] Preferably, the weight ratio of the A2 component to the B component is 10:(0.2-2.8), and more preferably 10:(1-1.8).

[0019] Preferably, the silane coupling agent includes KH550 or KH560. After the silane coupling agent is hydrolyzed by a solvent, it is beneficial to graft and modify the surface of inorganic and organic substances, thereby improving the compatibility of the components, and further, it is beneficial to improve the wear resistance and corrosion resistance of the coating formed by the coating.

[0020] Preferably, the A1 component and the A2 component further include an auxiliary agent, and the auxiliary agent includes at least one of a defoaming agent and nonylphenol polyethylene glycol.

[0021] Preferably, the defoaming agent is polydimethylsiloxane.

[0022] Preferably, the solvent comprises ethanol and water.

[0023] Preferably, the weight ratio of ethanol to water is 1:(1-5), more preferably 1:(2-4).

[0024] Preferably, the isocyanate curing agent includes at least one of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and hexamethylene diisocyanate (HDI).

[0025] Preferably, the A2 component also includes 3-fluoro-4-hydroxybenzoic acid. The introduction of this substance can participate in the cross-linking curing reaction, and the introduction of fluorine is also beneficial to further improve the wear resistance and corrosion resistance of the coating formed by the coating.

[0026] Preferably, in the A2 component, the content of 3-fluoro-4-hydroxybenzoic acid is 5-20 parts.

[0027] A second aspect of the present invention provides a method for preparing a corrosion-resistant and wear-resistant functional gradient coating.

[0028] A method for preparing a corrosion-resistant and wear-resistant functional gradient coating comprises the following steps: Take A1 raw material components, mix them, and obtain the A1 component; Take A2 raw material components, mix them, and obtain the A2 component; Component B is taken to form the corrosion-resistant and wear-resistant functional gradient coating with the components A1 and A2.

[0029] A third aspect of the present invention provides an application of a corrosion-resistant and wear-resistant functional gradient coating.

[0030] A device, the surface of which comprises a coating formed by the above-mentioned corrosion-resistant and wear-resistant functional gradient coating.

[0031] Preferably, the material of the device includes metal.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows: The corrosion-resistant and wear-resistant functional gradient coating of the present invention is formed by the A1 component and the A2 component composed of specific components, and isocyanate curing agent, to form a gradient protective coating on the surface of the substrate, thereby having good corrosion resistance and wear resistance at the same time. The corrosion-resistant and wear-resistant functional gradient coating of the present invention is applied to the surface of metal equipment, and the formed coating has good corrosion resistance and wear resistance, which can significantly improve the service life of the metal equipment. DETAILED DESCRIPTION

[0033] 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.

[0034] Example 1

[0035] A corrosion-resistant and wear-resistant functional gradient coating, comprising an A1 component, an A2 component, and a B component; The A1 component includes, by weight: 10 parts of 4-hydroxybutyl vinyl ether, 65 parts of water-based hydroxy acrylic resin, 15 parts of dihydroxy polydimethylsiloxane, 70 parts of water, 20 parts of the first modified filler, and 0.5 parts of polydimethylsiloxane; Component A2, by weight, includes: 5 parts of pentaerythritol, 8 parts of trihydroxybenzoic acid, 70 parts of water-based hydroxy acrylic resin, 80 parts of water and 20 parts of the second modified filler, and 0.5 parts of polydimethylsiloxane; Component B includes: an isocyanate curing agent (toluene diisocyanate) and dibutyltin dilaurate, and the weight ratio of toluene diisocyanate to dibutyltin dilaurate is 1:0.2; The preparation process of the first modified filler is as follows: nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, silane coupling agent KH550, and a solvent (the solvent is composed of ethanol and water in a weight ratio of 1:2) are mixed, and then polyethylene glycol is added for ultrasonic dispersion for 30 minutes to obtain the first modified filler, wherein the weight ratio of nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, silane coupling agent KH550, solvent, and polyethylene glycol is 1:2:0.3:1.5:3:15:4; The preparation process of the second modified filler is: mix nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent KH550, and solvent (the solvent is composed of ethanol and water in a weight ratio of 1:2), and then add polyethylene glycol for ultrasonic dispersion for 30 minutes to obtain the second modified filler. The weight ratio of nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent KH550, solvent, and polyethylene glycol is 1:1.8:0.5:0.4:2:3:15:3.

[0036] The weight ratio of component A1 to component B is 10:1; The weight ratio of component A2 to component B is 10:1.2.

[0037] A method for preparing a corrosion-resistant and wear-resistant functional gradient coating comprises the following steps: Take A1 raw material component, mix, and obtain A1 component; Take A2 raw material component, mix, and obtain A2 component; Component B, component A1 and component A2 are taken to form a corrosion-resistant and wear-resistant functional gradient coating.

[0038] Example 2

[0039] A corrosion-resistant and wear-resistant functional gradient coating, comprising an A1 component, an A2 component, and a B component; The A1 component includes, by weight: 10 parts of 4-hydroxybutyl vinyl ether, 70 parts of water-based hydroxy acrylic resin, 16 parts of dihydroxy polydimethylsiloxane, 75 parts of water, 22 parts of the first modified filler, and 0.5 parts of polydimethylsiloxane; Component A2, by weight, includes: 5 parts of pentaerythritol, 9 parts of trihydroxybenzoic acid, 65 parts of water-based hydroxy acrylic resin, 80 parts of water and 18 parts of the second modified filler, and 0.5 parts of polydimethylsiloxane; Component B includes: an isocyanate curing agent (hexamethylene diisocyanate) and dibutyltin dilaurate, and the weight ratio of toluene diisocyanate to dibutyltin dilaurate is 1:0.3; The preparation process of the first modified filler is as follows: nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, silane coupling agent KH550, and a solvent (the solvent is composed of ethanol and water in a weight ratio of 1:2) are mixed, and then polyethylene glycol is added for ultrasonic dispersion for 30 minutes to obtain the first modified filler, wherein the weight ratio of nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, silane coupling agent KH550, solvent, and polyethylene glycol is 1:2.1:0.4:1.6:3:15:4; The preparation process of the second modified filler is: mix nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent KH550, and solvent (the solvent is composed of ethanol and water in a weight ratio of 1:2), and then add polyethylene glycol for ultrasonic dispersion for 30 minutes to obtain the second modified filler. The weight ratio of nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent KH550, solvent, and polyethylene glycol is 1:1.9:0.6:0.5:2.1:3:15:3.

[0040] The weight ratio of component A1 to component B is 10:1.1; The weight ratio of component A2 to component B is 10:1.1.

[0041] A method for preparing a corrosion-resistant and wear-resistant functional gradient coating comprises the following steps: Take A1 raw material components, mix them, and obtain A1 component; Take A2 raw material component, mix, and obtain A2 component; Component B, component A1 and component A2 are taken to form a corrosion-resistant and wear-resistant functional gradient coating.

[0042] Example 3

[0043] Compared with Example 1, the only difference in Example 3 is that component A2 further contains 8 parts by weight of 3-fluoro-4-hydroxybenzoic acid, and the other components and processes are the same as those in Example 1.

[0044] Comparative Example 1

[0045] Compared with Example 1, the difference of Comparative Example 1 is that an equal amount of water-based hydroxylated acrylic resin is used to replace 4-hydroxybutyl vinyl ether, and other components and processes are the same as those of Example 1.

[0046] Comparative Example 2

[0047] Compared with Example 1, the difference of Comparative Example 2 is that an equal amount of pentaerythritol is used to replace trihydroxybenzoic acid, and other components and processes are the same as those of Example 1.

[0048] Comparative Example 3

[0049] Compared with Example 1, the difference of Comparative Example 3 is that in component A2, an equal amount of sodium dodecyl sulfate is used instead of sodium lauryl sulfate, and an equal amount of hexagonal boron nitride is used instead of nano molybdenum disulfide. Other components and processes are the same as those in Example 1.

[0050] Product effect testing

[0051] The coatings prepared in Examples 1-3 and Comparative Examples 1-3 were respectively applied on the surface of a stainless steel plate (component A1 was mixed with component B and applied on the surface of the stainless steel plate to form a first functional layer, and then component A2 was mixed with component B and applied on the first functional layer to form a second functional layer), first cured at 70°C for 30 minutes and then cured at 150°C for 15 minutes to obtain a coating with a thickness of about 70 μm.

[0052] 1. Wear resistance test

[0053] Referring to DIN 68861T2 standard, the wear resistance of the coatings prepared in Examples 1-3 and Comparative Examples 1-3 was tested using an Abraser 5130 wear tester. S-33 sandpaper was used as the friction material, the test load was 500 g, and new sandpaper was used every 100 tests. The wear amount of the coating corresponding to 400 turns was tested (wear amount = sample mass before wear resistance test - sample mass after wear resistance test). The results are shown in Table 1.

[0054] Table 1 Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Wear amount (mg) 80.2 78.8 70.5 81.3 98.6 102.2 As can be seen from Table 1, the wear resistance of the coating corresponding to the embodiment is better than that of the comparative example. It can be seen from the results of Example 1 and Comparative Examples 1-3 that when the A1 component is changed, the wear resistance of the coating is less affected. The reason is that there is also a film layer formed by the A2 component on the surface of the A1 component, and the film layer formed by the A2 component has a greater impact on the wear resistance. It can be seen from the results of Example 1 and Comparative Examples 2-3 that when pentaerythritol is used to replace trihydroxybenzoic acid, the wear resistance of the coating is significantly reduced. The main reason may be that the film layer formed by the A2 component lacks the skeleton structure of trihydroxybenzoic acid, which reduces the stability of the coating. When sodium lauryl sulfate is used instead of sodium lauryl sulfate, and an equal amount of hexagonal boron nitride is used instead of nano molybdenum disulfide, it is not conducive to the uniform dispersion of the second modified filler, thereby significantly reducing the wear resistance of the coating.

[0055] 2. Corrosion resistance test

[0056] The salt water resistance and alkali resistance of the coatings formed by the coatings prepared in the above Example 1, Example 3, Comparative Example 1 and Comparative Example 3 were tested with reference to GB / T 9274-1988 standard. The results are shown in Table 2.

[0057] Table 2 Salt water resistance (3% mass fraction NaCl solution, 360h) Alkali resistance (20% mass fraction NaOH solution, 120h) Example 1 No bubbles, cracks or shedding No bubbles, cracks or shedding Example 3 No bubbles, cracks or shedding No bubbles, cracks or shedding Comparative Example 1 Bubbling, cracking, no falling off Bubbling, cracking, obvious shedding Comparative Example 3 Bubbling, cracking, no falling off Bubbling, cracks, partial peeling It can be seen from Table 2 that the coating corresponding to the embodiment has better corrosion resistance than the comparative example.

[0058] In addition, the coatings of Example 1 and Example 3 tested according to the conditions in Table 2 were taken, and then the wear amount of the coatings was tested according to the conditions corresponding to Table 1. The results showed that the wear amount corresponding to Example 1 was 85.9 mg, and the wear amount corresponding to Example 3 was 71.9 mg. It can be further seen that Example 3 has obvious improvements in corrosion resistance and wear resistance compared to Example 1.

[0059] It should be noted that, in this article, terms such as "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or equipment that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment.

[0060] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A corrosion-resistant and wear-resistant functional gradient coating, characterized in that: It includes component A1, component A2 and component B; The A1 component comprises, by weight: 10 parts of 4-hydroxybutyl vinyl ether, 60-80 parts of water-based hydroxylated acrylic resin, 10-25 parts of dihydroxy polydimethylsiloxane, 60-140 parts of water and 10-40 parts of the first modified filler; The A2 component comprises, by weight: 5 parts of pentaerythritol, 5-15 parts of trihydroxybenzoic acid, 60-80 parts of water-based hydroxy acrylic resin, 60-140 parts of water and 15-50 parts of a second modified filler; The B component includes: an isocyanate curing agent; The preparation process of the first modified filler is: mixing nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, a silane coupling agent, and a solvent, and then adding polyethylene glycol for ultrasonic dispersion to obtain the first modified filler; The preparation process of the second modified filler is: mixing nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent and solvent, and then adding polyethylene glycol for ultrasonic dispersion to obtain the second modified filler.

2. The corrosion-resistant and wear-resistant functional gradient coating according to claim 1, characterized in that: In the first modified filler, the weight ratio of nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, silane coupling agent, solvent and polyethylene glycol is 1: (1.5-3): (0.2-0.9): (1-5): (2-10): (10-30): (2-10).

3. The corrosion-resistant and wear-resistant functional gradient coating according to claim 1, characterized in that: In the second modified filler, the weight ratio of nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, silane coupling agent, solvent, and polyethylene glycol is 1: (1.5-3): (0.1-1): (0.2-0.9): (1-5): (2-10): (10-30): (2-10).

4. The corrosion-resistant and wear-resistant functional gradient coating according to claim 1, characterized in that: The B component also includes dibutyltin dilaurate.

5. A corrosion-resistant and wear-resistant functional gradient coating according to any one of claims 1 to 4, characterized in that: The weight ratio of the A1 component to the B component is 10:(0.5-3); and / or the weight ratio of the A2 component to the B component is 10:(0.2-2.8).

6. The corrosion-resistant and wear-resistant functional gradient coating according to claim 5, characterized in that: The A1 component and the A2 component also include auxiliary agents, and the auxiliary agents include at least one of a defoaming agent and nonylphenol polyethylene glycol.

7. The corrosion-resistant and wear-resistant functional gradient coating according to claim 5, characterized in that: The solvents include ethanol and water.

8. The corrosion-resistant and wear-resistant functional gradient coating according to claim 5, characterized in that: The isocyanate curing agent includes at least one of toluene diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate.

9. The method for preparing a corrosion-resistant and wear-resistant functional gradient coating according to any one of claims 1 to 8, characterized in that: The following steps are involved: Take A1 raw material components, mix them, and obtain the A1 component; Take A2 raw material components, mix them, and obtain the A2 component; Component B is taken to form the corrosion-resistant and wear-resistant functional gradient coating with the components A1 and A2.

10. A device, characterized in that: Its surface comprises a coating formed by a corrosion-resistant and wear-resistant functional gradient coating as described in any one of claims 1-8.