A corrosion-resistant and wear-resistant functional gradient coating and its preparation method

Abstract

The invention discloses a corrosion-resistant and wear-resistant functional gradient coating and a preparation method thereof, belonging to the technical field of coatings. The corrosion-resistant and wear-resistant functional gradient coating of the present invention comprises 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 a water-based hydroxylated acrylic resin, 10-25 parts of dihydroxy polydimethylsiloxane, 60-140 parts of water, and 10-40 parts of a first modified filler; the A2 component comprises, by weight, 5 parts of pentaerythritol, 5-15 parts of trihydroxybenzoic acid, 60-80 parts of a water-based hydroxylated acrylic resin, 60-140 parts of water, and 15-50 parts of a second modified filler; and the B component comprises an isocyanate curing agent. The coating formed by the corrosion-resistant and wear-resistant functional gradient coating of the present invention 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 widespread and causes significant economic losses annually. Coatings have a wide range of uses. For example, applying coatings to metal surfaces not only provides a decorative effect but also provides excellent protection. They can reduce corrosion and wear on metal equipment, thereby extending its service life. Furthermore, applying coatings to wooden furniture can also protect and extend its lifespan.

[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 achieved 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 functionally gradient coating and a preparation method thereof. The functionally gradient coating of the present invention forms a coating having both good corrosion resistance and wear resistance.

[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 component A1, component A2, and component B;

[0008] 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;

[0009] 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;

[0010] The B component includes: an isocyanate curing agent;

[0011] 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;

[0012] 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, then adding polyethylene glycol for ultrasonic dispersion to obtain the second modified filler.

[0013] 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 can 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, which is cured to form a corrosion-resistant and wear-resistant functional gradient coating layer having good corrosion resistance and wear resistance.

[0014] 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. Simultaneously, the skeleton structures of 4-hydroxybutyl vinyl ether, water-based hydroxy acrylic resin, and dihydroxy polydimethylsiloxane are introduced, and modified fillers are combined to uniformly disperse the modified fillers in a spatial network structure formed by the cross-linking reaction. This fully utilizes the effects of nano-sodium silicate, nano-titanium dioxide, and nano-manganese dioxide. Even if external acid and alkali corrosive substances penetrate into the second functional layer, they are extremely difficult to penetrate into the first functional layer.

[0015] The A2 component 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. At the same time, the skeleton structure of pentaerythritol, trihydroxybenzoic acid, and water-based hydroxy acrylic resin is introduced, and modified fillers are combined to make the modified fillers uniformly dispersed in the spatial network structure formed by the cross-linking reaction, thereby giving full play to the corrosion resistance and wear resistance of nano-sodium silicate, nano-titanium dioxide, carbon nanotubes, and nano-molybdenum disulfide, 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.

[0016] The present invention achieves good compatibility and high bonding strength between components A1 and A2 through specific selection of components in the present invention, and is conducive to fully exerting the anti-corrosion and wear-resistant functions of components A1 and A2, thereby simultaneously solving the problem in the prior art that it is difficult to achieve both anti-corrosion and wear-resistant properties in coatings.

[0017] 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).

[0018] 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).

[0019] 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).

[0020] Preferably, the B component further comprises dibutyltin dilaurate. Adding a catalyst is beneficial for a more complete cross-linking reaction.

[0021] Preferably, in the component B, the weight ratio of isocyanate to dibutyltin dilaurate is 1:(0.05-0.4), more preferably 1:(0.2-0.4).

[0022] Preferably, the weight ratio of the component A1 to the component B is 10:(0.5-3), more preferably 10:(1-2).

[0023] Preferably, the weight ratio of the A2 component to the B component is 10:(0.2-2.8), more preferably 10:(1-1.8).

[0024] 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.

[0025] 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.

[0026] Preferably, the defoaming agent is polydimethylsiloxane.

[0027] Preferably, the solvent includes ethanol and water.

[0028] Preferably, the weight ratio of ethanol to water is 1:(1-5), more preferably 1:(2-4).

[0029] Preferably, the isocyanate curing agent includes at least one of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and hexamethylene diisocyanate (HDI).

[0030] Preferably, the A2 component also includes 3-fluoro-4-hydroxybenzoic acid. The introduction of this substance can participate in the cross-linking and 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.

[0031] Preferably, the content of 3-fluoro-4-hydroxybenzoic acid in the A2 component is 5-20 parts.

[0032] A second aspect of the present invention provides a method for preparing a corrosion-resistant and wear-resistant functional gradient coating.

[0033] A method for preparing a corrosion-resistant and wear-resistant functional gradient coating comprises the following steps:

[0034] Take A1 raw material components, mix them, and obtain the A1 component;

[0035] Take A2 raw material components, mix them, and obtain the A2 component;

[0036] Component B is taken to form the corrosion-resistant and wear-resistant functional gradient coating together with the component A1 and the component A2.

[0037] A third aspect of the present invention provides an application of a corrosion-resistant and wear-resistant functional gradient coating.

[0038] A device, the surface of which comprises a coating formed by the above-mentioned corrosion-resistant and wear-resistant functional gradient coating.

[0039] Preferably, the material of the device includes metal.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The corrosion-resistant and wear-resistant functionally gradient coating of the present invention forms a gradient protective coating on the substrate surface using specific components A1 and A2, combined with an isocyanate curing agent. This coating exhibits both excellent corrosion and wear resistance. When applied to the surface of metal equipment, the resulting coating exhibits excellent corrosion and wear resistance, significantly extending the service life of the metal equipment. DETAILED DESCRIPTION

[0042] 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 embodiments described 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 making any creative efforts shall fall within the scope of protection of the present invention.

[0043] Example 1

[0044] A corrosion-resistant and wear-resistant functional gradient coating, comprising component A1, component A2, and component B;

[0045] The A1 component comprises, by weight, 10 parts of 4-hydroxybutyl vinyl ether, 65 parts of water-based hydroxylated acrylic resin, 15 parts of dihydroxy polydimethylsiloxane, 70 parts of water, 20 parts of the first modified filler, and 0.5 parts of polydimethylsiloxane;

[0046] Component A2, calculated by weight, includes: 5 parts of pentaerythritol, 8 parts of trihydroxybenzoic acid, 70 parts of water-based hydroxy acrylic resin, 80 parts of water, 20 parts of the second modified filler, and 0.5 parts of polydimethylsiloxane;

[0047] 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;

[0048] The first modified filler is prepared by mixing 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), then adding polyethylene glycol and ultrasonically dispersing 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;

[0049] The preparation process of the second modified filler is as follows: 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 polyethylene glycol is added and ultrasonically dispersed 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.

[0050] The weight ratio of component A1 to component B is 10:1;

[0051] The weight ratio of component A2 to component B is 10:1.2.

[0052] A method for preparing a corrosion-resistant and wear-resistant functional gradient coating comprises the following steps:

[0053] Take A1 raw material components, mix them, and obtain A1 component;

[0054] Take A2 raw material components, mix them, and obtain A2 component;

[0055] Component B, component A1 and component A2 are taken to form a corrosion-resistant and wear-resistant functional gradient coating.

[0056] Example 2

[0057] A corrosion-resistant and wear-resistant functional gradient coating, comprising component A1, component A2, and component B;

[0058] The A1 component comprises, by weight, 10 parts of 4-hydroxybutyl vinyl ether, 70 parts of water-based hydroxylated acrylic resin, 16 parts of dihydroxy polydimethylsiloxane, 75 parts of water, 22 parts of the first modified filler, and 0.5 parts of polydimethylsiloxane;

[0059] Component A2, calculated by weight, includes: 5 parts of pentaerythritol, 9 parts of trihydroxybenzoic acid, 65 parts of water-based hydroxy acrylic resin, 80 parts of water, 18 parts of the second modified filler, and 0.5 parts of polydimethylsiloxane;

[0060] 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;

[0061] The first modified filler was prepared by mixing nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, silane coupling agent KH550, and a solvent (the solvent was composed of ethanol and water in a weight ratio of 1:2), and then adding polyethylene glycol and ultrasonically dispersing for 30 minutes to obtain the first modified filler. The weight ratio of nano sodium silicate, nano titanium dioxide, nano manganese dioxide, sodium lauryl sulfate, silane coupling agent KH550, solvent, and polyethylene glycol was 1:2.1:0.4:1.6:3:15:4.

[0062] The preparation process of the second modified filler is as follows: nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, 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), and then polyethylene glycol is added and ultrasonically dispersed 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.

[0063] The weight ratio of component A1 to component B is 10:1.1;

[0064] The weight ratio of component A2 to component B is 10:1.1.

[0065] A method for preparing a corrosion-resistant and wear-resistant functional gradient coating comprises the following steps:

[0066] Take A1 raw material components, mix them, and obtain A1 component;

[0067] Take A2 raw material components, mix them, and obtain A2 component;

[0068] Component B, component A1 and component A2 are taken to form a corrosion-resistant and wear-resistant functional gradient coating.

[0069] Example 3

[0070] 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.

[0071] Comparative Example 1

[0072] Compared with Example 1, the only difference of Comparative Example 1 is that an equal amount of water-based hydroxy acrylic resin is used instead of 4-hydroxybutyl vinyl ether, and other components and processes are the same as those of Example 1.

[0073] Comparative Example 2

[0074] Compared with Example 1, the only difference in Comparative Example 2 is that an equal amount of pentaerythritol is used instead of trihydroxybenzoic acid, and other components and processes are the same as those in Example 1.

[0075] Comparative Example 3

[0076] Compared with Example 1, the only difference of Comparative Example 3 is that, in component A2, an equal amount of 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. The other components and processes are the same as those in Example 1.

[0077] Product effect testing

[0078] 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 to 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 approximately 70 μm.

[0079] 1. Wear resistance test

[0080] With reference to the 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 abraser. 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.

[0081] Table 1

[0082] 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

[0083] 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. As can be seen from the results of Example 1 and Comparative Examples 1-3, 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. As can be seen from the results of Example 1 and Comparative Examples 2-3, 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 to replace sodium lauryl sulfate, and an equal amount of hexagonal boron nitride is used to replace 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.

[0084] 2. Corrosion resistance test

[0085] The salt water resistance and alkali resistance of the coatings formed by the coatings prepared in Example 1, Example 3, Comparative Example 1, and Comparative Example 3 were tested with reference to GB / T 9274-1988. The results are shown in Table 2.

[0086] Table 2

[0087] 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, not falling off Blistering, cracking, and obvious shedding Comparative Example 3 Bubbling, cracking, not falling off Blistering, cracking, partial falling off

[0088] It can be seen from Table 2 that the coating corresponding to the embodiment has better corrosion resistance than that of the comparative example.

[0089] In addition, the coatings of Example 1 and Example 3, after being tested according to the conditions in Table 2, were then tested for wear according to the conditions in Table 1. The results showed that the wear loss of Example 1 was 85.9 mg, and the wear loss of Example 3 was 71.9 mg. This further shows that Example 3 has significantly improved corrosion resistance and wear resistance compared to Example 1.

[0090] It should be noted that, in this document, terms such as "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements that are inherent to such process, method, article or apparatus.

[0091] While 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 these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A corrosion-resistant and wear-resistant functional gradient coating, characterized in that: Including A1 component, A2 component, and 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 as follows: mixing nano sodium silicate, nano titanium dioxide, carbon nanotubes, nano molybdenum disulfide, sodium lauryl sulfate, a silane coupling agent, and a solvent, and then adding polyethylene glycol for ultrasonic dispersion to obtain the second modified filler; When the corrosion-resistant and wear-resistant functional gradient coating is used, component A1 is mixed with component B and coated on a substrate 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.

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. The 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 further 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 together with the component A1 and the component A2.

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