Oil-resistant anticorrosive and static-conductive polyurea coating material, preparation method and application thereof

Abstract

This invention discloses an oil-resistant, corrosion-resistant, and electrostatic-dissipative polyurea coating, its preparation method, and its application. The components of this oil-resistant, corrosion-resistant, and electrostatic-dissipative polyurea coating include polyaspartic acid ester resin, fluorinated polyamine resin, rust-inhibiting pigments and fillers, conductive fillers, dispersants, defoamers, leveling agents, rheology modifiers, diluents, dehydrating agents, and aliphatic isocyanate curing agents. Its preparation method is very simple; all components are mixed evenly in batches. The polyurea coating of this invention can form a thick film with a single coat, resulting in high construction efficiency. The film exhibits excellent oil resistance, corrosion resistance, electrostatic conductivity, and mechanical properties, making it suitable for use as an inner wall protective coating for crude oil storage tanks. Furthermore, the preparation method of this polyurea coating is simple, making it suitable for large-scale industrial production and application.

Description

Technical Field

[0001] This invention relates to the field of metal corrosion protection technology, specifically to an oil-resistant, corrosion-resistant, and static-dissipating polyurea coating, its preparation method, and its application. Background Technology

[0002] Crude oil storage tanks are essential infrastructure in the petroleum industry, primarily made of metal. Crude oil contains inorganic salts, organic salts, and water, which can cause electrochemical corrosion of the tanks. Severe corrosion can lead to oil leaks. Oil leaks not only severely pollute the environment but also easily cause fires and explosions, posing a significant threat to human safety. Furthermore, the flow, filtration, and extraction of liquid petroleum within the tank can generate static electricity due to friction, posing a risk of electrostatic ignition and explosion. Currently, protection is mainly achieved by coating the inner walls of crude oil storage tanks with water-based / solvent-based anti-corrosion and anti-static epoxy coatings. However, existing water-based / solvent-based anti-corrosion and anti-static epoxy coatings generally suffer from limited oil resistance, insufficient anti-corrosion durability (protection effectiveness typically only lasts about 3 years), and numerous application steps (a single coat only produces a film thickness of about 50μm, requiring multiple coats to achieve the desired thickness), failing to fully meet practical application requirements.

[0003] Therefore, it is of great significance to develop an anti-corrosion coating with excellent oil resistance, excellent corrosion resistance, good static conductivity, and a thick film formed in a single coat. Summary of the Invention

[0004] The purpose of this invention is to provide an oil-resistant, corrosion-resistant, and static-dissipative polyurea coating, its preparation method, and its application.

[0005] The technical solution adopted in this invention is:

[0006] An oil-resistant, corrosion-resistant, and static-dissipative polyurea coating comprises the following components in parts by weight:

[0007] Component A:

[0008] Polyaspartic acid ester resin: 40 parts to 60 parts;

[0009] Fluorinated polyamine resin: 3 to 10 parts;

[0010] Rust-inhibiting pigments and fillers: 5 to 10 parts;

[0011] Conductive filler: 18 to 25 parts;

[0012] Dispersant: 0.4 parts to 1 part;

[0013] Defoamer: 0.3 to 1.2 parts;

[0014] Leveling agent: 0.3 parts to 0.8 parts;

[0015] Rheology modifier: 0.5 parts to 1.5 parts;

[0016] Diluent: 2 to 5 parts;

[0017] Dehydrating agent: 3 to 7 parts;

[0018] Component B:

[0019] Aliphatic isocyanate curing agent: 94 to 98 parts;

[0020] Diluent: 2 to 5 parts.

[0021] Preferably, the polyaspartic acid ester resin is compounded from polyaspartic acid ester resin F520 of Shenzhen Feiyang Junyan New Material Co., Ltd. and polyaspartic acid ester resin F420 of Shenzhen Feiyang Junyan New Material Co., Ltd. in a mass ratio of 1.5 to 4.5:1.

[0022] Preferably, the fluorinated polyamine resin is prepared by a method comprising the following steps:

[0023] a) Disperse the polyamine in a solvent, then add a fluorinated carboxylic acid ester to react and obtain a fluorinated polyamine intermediate;

[0024] b) The fluorinated polyamine intermediate is added to a reducing agent solution for reaction to obtain the fluorinated polyamine resin.

[0025] More preferably, the fluorinated polyamine resin is prepared by a method comprising the following steps:

[0026] a) Disperse the polyamine in a solvent, then slowly add a fluorinated carboxylic acid ester to react, and then remove impurities by vacuum distillation to obtain a fluorinated polyamine intermediate;

[0027] b) Dissolve the fluorinated polyamine intermediate in a solvent, then slowly add it to a reducing agent solution to react. Filter the solution, and remove impurities by rotary evaporation of the filtrate to obtain the fluorinated polyamine resin.

[0028] Preferably, the molar ratio of the polyamine and the fluorinated carboxylic acid ester in step a) is 1:2.5 to 3.0.

[0029] Preferably, the polyamine in step a) is at least one of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-(2-ethylamino)-1,3-propanediamine, N,N'-di(2-aminoethyl)-1,3-propanediamine, N,N'-bis(3-aminopropyl)ethylenediamine, and N,N'-di(3-aminopropyl)-1,3-propanediamine.

[0030] Preferably, the solvent in step a) is methanol.

[0031] Preferably, the fluorinated carboxylic acid ester in step a) is at least one of methyl heptafluorobutyrate, ethyl heptafluorobutyrate, methyl nonafluorovalerate, ethyl nonafluorovalerate, methyl undecanoate, ethyl perfluorooctanoate, and ethyl heptadecafluorononanoate.

[0032] Preferably, the reaction in step a) is carried out at a temperature of 30°C to 90°C.

[0033] Preferably, the solvent in step b) is tetrahydrofuran.

[0034] Preferably, the molar ratio of amide groups to reducing agent in the fluorinated polyamine intermediate in step b) is 1:2 to 3.

[0035] Preferably, the reducing agent in step b) is at least one of lithium aluminum hydride, tetrahydrofuran borane complex, and sodium borohydride.

[0036] Preferably, the reaction in step b) is carried out at a temperature of 5°C to 80°C for a reaction time of 4 to 48 hours.

[0037] Preferably, the rust-preventive pigment and filler is at least one of aluminum tripolyphosphate, aluminum zinc phosphate, molybdate, and zinc phosphate.

[0038] Preferably, the conductive filler is conductive mica powder.

[0039] More preferably, the conductive filler is at least one of the following: conductive mica powder BC-P from Shanghai Junjiang Technology Co., Ltd., conductive mica powder BC-C from Shanghai Junjiang Technology Co., Ltd., conductive mica powder BC-C10 from Shanghai Junjiang Technology Co., Ltd., and conductive mica powder from Guangzhou Yijie Technology Co., Ltd.

[0040] Preferably, the dispersant is a polyurethane polymer dispersant. Polyurethane polymer dispersants have excellent pigment stability and low-temperature stability.

[0041] Preferably, the defoamer is a silicone defoamer. Silicone defoamers not only have excellent foam-suppressing ability, but also can quickly eliminate bubbles present in the coating system, especially exhibiting excellent ability to break reactive bubbles.

[0042] Preferably, the leveling agent is a fluorocarbon-modified polyacrylate. Fluorocarbon-modified polyacrylate can significantly reduce the surface tension of the coating, prevent pinholes, and help enhance the adhesion of the paint film.

[0043] Preferably, the rheology modifier is micronized polyamide-modified hydrogenated castor oil. Micronized polyamide-modified hydrogenated castor oil can promote the establishment of a three-dimensional structure in the coating system, and the resulting thixotropic flowability can prevent sedimentation and improve anti-sagging properties without affecting coating leveling.

[0044] Preferably, the diluent is an ether ester solvent.

[0045] More preferably, the diluent is at least one of n-butyl acetate, propyl carbonate, diisopentyl methyl phosphate, and diisononyl phthalate.

[0046] Preferably, the dehydrating agent is a molecular sieve.

[0047] Preferably, the aliphatic isocyanate curing agent is at least one selected from hexamethylene diisocyanate trimer, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and methylcyclohexyl diisocyanate.

[0048] A method for preparing an oil-resistant, corrosion-resistant, and static-dissipative polyurea coating as described above includes the following steps:

[0049] 1) Mix polyaspartic acid ester resin and fluorinated polyamine resin, then add dispersant, defoamer and leveling agent and mix well, then add rust-inhibiting pigments and fillers and conductive fillers and mix well, then add rheology modifier, diluent and dehydrating agent and mix well to obtain component A, and mix aliphatic isocyanate curing agent and diluent to obtain component B.

[0050] 2) Mix component A and component B thoroughly to obtain an oil-resistant, corrosion-resistant, and static-dissipative polyurea coating.

[0051] Preferably, a method for preparing an oil-resistant, corrosion-resistant, and static-dissipative polyurea coating as described above includes the following steps:

[0052] 1) Add polyaspartic acid ester resin and fluorinated polyamine resin to a mixer and stir and disperse for 5 min to 10 min at a mixer speed of 800 rpm to 1500 rpm. Then add dispersant, defoamer and leveling agent and continue stirring and dispersing for 5 min to 10 min. Then add rust-inhibiting pigments and fillers and conductive fillers. Adjust the mixer speed to 2500 rpm to 3000 rpm and stir and disperse for 15 min to 20 min. Then add rheology modifier, diluent and dehydrating agent. Adjust the mixer speed to 1200 rpm to 1700 rpm and stir and disperse for 10 min to 15 min to obtain component A. Mix the aliphatic isocyanate curing agent and diluent to obtain component B.

[0053] 2) Mix component A and component B thoroughly to obtain an oil-resistant, corrosion-resistant, and static-dissipative polyurea coating.

[0054] An oil-resistant, corrosion-resistant, and static-dissipative polyurea coating as described above is used for metal corrosion protection applications.

[0055] The beneficial effects of the present invention are: the polyurea coating of the present invention can form a thick paint film in one coat, with high construction efficiency, excellent oil resistance, excellent anti-corrosion performance, good static conductivity and excellent mechanical properties, making it suitable as an inner wall protective coating for crude oil storage tanks. Moreover, the preparation method of the polyurea coating is simple and suitable for large-scale industrial production and application.

[0056] Specifically:

[0057] 1) The polyurea coating of the present invention contains a fluorinated polyamine resin, which can increase the crosslinking density of the paint film, which is beneficial to enhance the salt spray resistance and acid and alkali resistance of the paint film, thereby improving the corrosion resistance of the paint film. In addition, the fluorocarbon chain in the fluorinated polyamine resin is beneficial to improving the oil resistance of the paint film.

[0058] 2) During the curing process, the aliphatic isocyanate curing agent of the polyurea coating of the present invention reacts with polyaspartic acid ester resin and fluorinated polyamine resin to generate urea groups that can form hydrogen bonds, forming a micro-phase separation structure at the molecular level, thereby endowing the coating film with excellent mechanical properties.

[0059] 3) The polyurea coating of the present invention forms a paint film with excellent resistance to media, such as solvent resistance (93# gasoline at 62°C), salt spray resistance, salt resistance (5% NaCl solution at room temperature), alkali resistance (5% NaOH solution at room temperature), and acid resistance (5% H2SO4 solution at room temperature), all of which can reach more than 1500 hours. It can also withstand boiling water for more than 50 hours, which fully meets the requirements for corrosion protection of steel crude oil storage tanks.

[0060] 4) The polyurea coating of the present invention contains conductive fillers, and the paint film has good static electricity conductivity, which can effectively avoid the problems of fire and explosion caused by static electricity;

[0061] 5) The fluorinated polyamine resin in the polyurea coating of the present invention is prepared by a two-step method with simple reaction conditions and high product yield.

[0062] 6) The ratio of fluorinated polyamine resin, polyaspartic acid ester resin and aliphatic isocyanate curing agent in the polyurea coating of the present invention is appropriate. The activation period of the coating and the hardness of the paint film can be flexibly adjusted. The thickness of the paint film formed by one application can reach tens to hundreds of micrometers. The required paint film thickness can be obtained in one application, which significantly improves the efficiency of construction.

[0063] 7) The preparation method of the polyurea coating of the present invention is simple and suitable for large-scale industrial production and application. Attached Figure Description

[0064] Figure 1 This is a high-resolution mass spectrum of the fluorinated polyamine intermediate in Example 1.

[0065] Figure 2 This is a high-resolution mass spectrum of the fluorinated polyamine resin in Example 1. Detailed Implementation

[0066] The present invention will be further explained and described below with reference to specific embodiments.

[0067] Example 1:

[0068] An oil-resistant, corrosion-resistant, and static-dissipating polyurea coating has the following composition:

[0069] Table 1. Composition of an oil-resistant, corrosion-resistant, and static-dissipating polyurea coating.

[0070]

[0071] Note:

[0072] The preparation method of fluorinated polyamine resin is as follows:

[0073] a) 15.9 g of tetraethylenepentamine and 7 g of methanol were stirred evenly, and then heated to 45 °C. 40 g of methyl heptafluorobutyrate was added dropwise to carry out the reaction. The reaction process was monitored by thin-layer chromatography. After the reaction was completed, impurities were removed by vacuum distillation to obtain a fluorinated polyamine intermediate.

[0074] b) Dissolve 30g of the fluorinated polyamine intermediate in 6g of tetrahydrofuran, and then add it dropwise to 260mL of a 1mol / L lithium aluminum hydride tetrahydrofuran solution. After the addition is complete, heat to 35℃ and react for 24h. After the reaction is complete, perform post-treatment with 9.9g of deionized water, 9.9g of 15% NaOH solution and 30g of deionized water respectively. Then add anhydrous magnesium sulfate to remove water, filter, and take the filtrate for rotary evaporation to remove impurities, thus obtaining the fluorinated polyamine resin.

[0075] The high-resolution mass spectrometry (HR-MS) image of the fluorinated polyamine intermediate in this embodiment is shown below. Figure 1 As shown, the HR-MS chromatogram of the fluorinated polyamine resin is as follows. Figure 2 As shown.

[0076] Depend on Figure 1 and Figure 2 It can be seen that: Fluorine-containing polyamine resin was successfully prepared in this embodiment, and the content of the target product in the synthesized product is high and the reaction yield is large, based on the signal intensity of the mass spectrometry.

[0077] The preparation method of the above-mentioned oil-resistant, corrosion-resistant, and static-dissipative polyurea coating is as follows:

[0078] 1) Add polyaspartic acid ester resin F520, polyaspartic acid ester resin F420, and fluorinated polyamine resin to a mixer and disperse at 1200 rpm for 10 minutes. Then add dispersant AFCONA-4071, defoamer AFCONA2605-5B, defoamer 768, and leveling agent AFCONA-3670, and continue to disperse for 10 minutes. Next, add aluminum tripolyphosphate and conductive mica powder, adjust the mixer speed to 2500 rpm, and disperse for 20 minutes. Finally, add rheology modifiers. MT, n-butyl acetate, and 3A molecular sieve were mixed and dispersed for 12 minutes after adjusting the speed of the stirrer to 1500 rpm to obtain component A; hexamethylene diisocyanate trimer TPA-100, isophorone diisocyanate, and n-butyl acetate were mixed evenly to obtain component B.

[0079] 2) Mix component A and component B evenly according to an NCO index of 1.1 to obtain an oil-resistant, corrosion-resistant, and static-dissipating polyurea coating.

[0080] Example 2:

[0081] An oil-resistant, corrosion-resistant, and static-dissipating polyurea coating is identical to the oil-resistant, corrosion-resistant, and static-dissipating polyurea coating in Example 1, except that it uses a different fluorinated polyamine resin (the amount added is the same).

[0082] Note:

[0083] The preparation method of fluorinated polyamine resin is as follows:

[0084] a) 15.9 g of tetraethylenepentamine and 7 g of methanol were stirred evenly, and then heated to 85 °C. 50.4 g of ethyl nonafluoropentanoate was added dropwise to carry out the reaction. The reaction process was monitored by thin-layer chromatography. After the reaction was completed, impurities were removed by vacuum distillation to obtain a fluorinated polyamine intermediate.

[0085] b) Dissolve 40g of fluorinated polyamine intermediate in 7g of tetrahydrofuran, and then add it dropwise to 289mL of 1mol / L lithium aluminum hydride tetrahydrofuran solution. After the addition is complete, heat to 45℃ and react for 24h. After the reaction is complete, post-treatment is performed sequentially with 11g of deionized water, 11g of 15% NaOH solution and 33g of deionized water. Then add anhydrous magnesium sulfate to remove water, filter, and take the filtrate for rotary evaporation to remove impurities, thus obtaining fluorinated polyamine resin.

[0086] Example 3:

[0087] An oil-resistant, corrosion-resistant, and static-dissipating polyurea coating is identical to the oil-resistant, corrosion-resistant, and static-dissipating polyurea coating in Example 1, except that it uses a different fluorinated polyamine resin (the amount added is the same).

[0088] Note:

[0089] The preparation method of fluorinated polyamine resin is as follows:

[0090] a) 15.9 g of tetraethylenepentamine and 7 g of methanol were stirred evenly, and then heated to 80 °C. 42 g of ethyl heptafluorobutyrate was added dropwise to carry out the reaction. The reaction process was monitored by thin-layer chromatography. After the reaction was completed, impurities were removed by vacuum distillation to obtain a fluorinated polyamine intermediate.

[0091] b) Dissolve 35g of fluorinated polyamine intermediate in 7g of tetrahydrofuran, and then add it dropwise to 290mL of 1mol / L lithium aluminum hydride tetrahydrofuran solution. After the addition is complete, heat to 35℃ and react for 24h. After the reaction is complete, post-treatment is performed sequentially with 11g of deionized water, 11g of 15% NaOH solution and 33g of deionized water. Then add anhydrous magnesium sulfate to remove water, filter, and take the filtrate for rotary evaporation to remove impurities, thus obtaining fluorinated polyamine resin.

[0092] Example 4:

[0093] An oil-resistant, corrosion-resistant, and static-dissipating polyurea coating has the following composition:

[0094] Table 2. Composition of an oil-resistant, corrosion-resistant, and static-dissipating polyurea coating.

[0095]

[0096]

[0097] Example 5:

[0098] An oil-resistant, corrosion-resistant, and static-dissipating polyurea coating has the following composition:

[0099] Table 3. Composition of an oil-resistant, corrosion-resistant, and static-dissipating polyurea coating.

[0100]

[0101]

[0102] Comparative Example 1:

[0103] A polyurea coating is identical to the oil-resistant, corrosion-resistant, and electrostatic-dissipative polyurea coating in Example 3, except that polyaspartic acid ester resin F420 is replaced with polyaspartic acid ester resin F520 (equal weight replacement) and fluorinated polyamine resin is replaced with polyaspartic acid ester resin F520 (equal weight replacement).

[0104] Comparative Example 2:

[0105] A polyurea coating is identical to the oil-resistant, corrosion-resistant, and static-dissipating polyurea coating in Example 3, except that polyaspartic acid ester resin F520 is replaced with polyaspartic acid ester resin F420 (replaced by equal weight).

[0106] Comparative Example 3:

[0107] A polyurea coating is identical to the oil-resistant, corrosion-resistant, and static-dissipating polyurea coating in Example 3, except that component B is replaced with 100 parts by weight of aromatic isocyanate MDI-50 (Wanhua).

[0108] Comparative Example 4:

[0109] Water-based anti-corrosion and conductive epoxy coating (YHW2502 water-based epoxy conductive anti-corrosion coating from Guangzhou Jietai Chemical Co., Ltd.)

[0110] Performance testing:

[0111] 1) The performance comparison table of the polyurea coatings in Example 3 and Comparative Examples 1-3 is shown in the table below:

[0112] Table 4. Performance Comparison of Polyurea Coatings in Example 3 and Comparative Examples 1-3

[0113]

[0114]

[0115] Note:

[0116] The coating film preparation process: The coating sample is scraped onto the steel plate using a coating scraper, and the thickness of the coating film is controlled to be 250μm~350μm. The coating film is then cured at room temperature for 7 days to obtain the coating film.

[0117] Surface drying time and complete drying time: Tested according to "GB / T 1728-2020 Determination of Drying Time of Paint Film and Putty Film";

[0118] Flexibility: Tested according to "GB / T 1731-2020 Test Method for Flexibility of Paint Film and Putty Film";

[0119] Impact resistance: Tested according to "GB / T 1732-2020 Test Method for Impact Resistance of Coating Film";

[0120] Adhesion: Tested according to "GB / T 9286-2021 Paints and Varnishes Cross-cut Test";

[0121] Pencil hardness: The test was conducted according to "GB / T 6739-2022 Pencil method for determining the hardness of paint and varnish film";

[0122] Boiling water resistance: Tested according to "GB / T 1733-1993 Test method for water resistance of paint film";

[0123] Gasoline resistance: Tested according to "SY / T 0319-2012 Technical Standard for Internal Anti-corrosion Coating of Steel Storage Tanks with Liquid Coating";

[0124] Acid resistance, alkali resistance and salt resistance: Tested according to Method A in "GB / T 9274-1988 Determination of resistance to liquid media of paints and varnishes";

[0125] Salt spray resistance: Tested according to "GB / T 1771-2007 Determination of resistance to neutral salt spray of paints and varnishes";

[0126] The index value is the performance index of conductive anti-corrosion coatings in the "GB / T 50393-2017 Technical Standard for Corrosion Protection Engineering of Steel Petroleum Storage Tanks".

[0127] As shown in Table 4:

[0128] a) The polyurea coating in Comparative Example 1 has only polyaspartic acid ester resin F520 as its resin component, which has low reactivity. Therefore, the paint film cures too slowly, foams severely, and has poor film density and poor resistance to media.

[0129] b) The resin components of the polyurea coating in Comparative Example 2 are polyaspartic acid ester resin F420 and fluorinated polyamine resin. Because F420 reacts too quickly, the coating cannot be applied to the substrate, so the practical value of the formulation is low.

[0130] c) The B component of the polyurea coating in Comparative Example 3 is the aromatic curing agent MDI-50, which has high reactivity and a reaction rate with water that is much greater than that of aliphatic isocyanates TPA-100 and IPDI. This results in obvious foaming of the paint film, reduced film density, and thus poor resistance to media.

[0131] d) The polyurea coating in Example 1 incorporates fluorinated polyamine resin. The multifunctional amine groups can increase the crosslinking density of the coating film, thereby improving the coating film's resistance to media. The fluorinated segments also help improve the coating film's oil and media resistance. The appropriate ratio of polyaspartic acid resin F520 / F420 can provide a suitable activation period. The curing agent, through the blending of aliphatic isocyanates, can not only adjust the activation period and expand the range of construction equipment, but also improve the coating film's resistance to media.

[0132] 2) The performance comparison table of the polyurea coatings in Examples 1-5 and the epoxy coating in Comparative Example 4 is shown below:

[0133] Table 5. Performance comparison of polyurea coatings in Examples 1-5 and epoxy coating in Comparative Example 4.

[0134]

[0135]

[0136] Note:

[0137] The coating film preparation process: The coating sample is scraped onto the steel plate using a coating scraper, and the thickness of the coating film is controlled to be 250μm~350μm. The coating film is then cured at room temperature for 7 days to obtain the coating film.

[0138] Surface resistivity: Tested in accordance with "GB / T 31838.3-2019 Dielectric and resistive properties of solid insulating materials - Part 3: Resistive properties (DC method) - Surface resistance and surface resistivity";

[0139] Adhesion: Tested according to "GB / T 5210-2006 Paint and Varnish Adhesion Test by Pull-Off Method".

[0140] As shown in Table 5:

[0141] a) Compared with the epoxy coating in Comparative Example 4, the polyurea coatings (containing fluorinated polyamine resin) in Examples 1-5 have better resistance to acid, alkali, salt, salt spray and gasoline for more than 1500 hours, and better resistance to boiling water for more than 60 hours. Their anti-corrosion and oil resistance are also superior.

[0142] b) The surface resistivity of the polyurea coatings formed in Examples 1 to 5 is within the specified range, indicating excellent electrostatic conductivity.

[0143] c) The epoxy coating in Comparative Example 4 has a dry film thickness of only 40μm to 60μm after one spraying, and multiple sprayings are required to achieve the specified thickness of 250μm to 350μm. In contrast, the polyurea coatings in Examples 1 to 5 have a high solid content, and the dry film thickness can reach the specified thickness of 250μm to 350μm after one spraying, which significantly improves the construction efficiency.

[0144] In summary, the oil-resistant, corrosion-resistant, and electrostatic-conductive polyurea coating of the present invention has high construction efficiency and low time cost, and the formed paint film has excellent oil resistance, corrosion resistance, and electrostatic conductivity.

[0145] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A polyurea coating that is oil-resistant, corrosion-resistant, and conductive, characterized in that, The components include the following parts by weight: Component A: Polyaspartic acid ester resin: 40 parts to 60 parts; Fluorinated polyamine resin: 3 to 10 parts; Rust-inhibiting pigments and fillers: 5 to 10 parts; Conductive filler: 18 to 25 parts; Dispersant: 0.4 parts to 1 part; Defoamer: 0.3 to 1.2 parts; Leveling agent: 0.3 parts to 0.8 parts; Rheology modifier: 0.5 parts to 1.5 parts; Diluent: 2 to 5 parts; Dehydrating agent: 3 to 7 parts; Component B: Aliphatic isocyanate curing agent: 94 to 98 parts; Diluent: 2 to 5 parts; The polyaspartic acid ester resin is compounded from polyaspartic acid ester resin F520 and polyaspartic acid ester resin F420 in a mass ratio of 1.5 to 4.5:

1. The fluorinated polyamine resin is prepared by a method comprising the following steps: a) dispersing a polyamine in a solvent, then adding a fluorinated carboxylic acid ester to react and obtain a fluorinated polyamine intermediate; b) adding the fluorinated polyamine intermediate to a reducing agent solution to react and obtain the fluorinated polyamine resin.

2. The oil-resistant, corrosion-resistant, and static-dissipating polyurea coating according to claim 1, characterized in that: In step a), the molar ratio of the polyamine and the fluorinated carboxylic acid ester is 1:2.5 to 3.0; in step b), the molar ratio of the amide group and the reducing agent in the fluorinated polyamine intermediate is 1:2 to 3.

3. The oil-resistant, corrosion-resistant, and static-dissipating polyurea coating according to claim 1, characterized in that: The polyamine in step a) is at least one of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-(2-ethylamino)-1,3-propanediamine, N,N'-di(2-aminoethyl)-1,3-propanediamine, N,N'-bis(3-aminopropyl)ethylenediamine, and N,N'-di(3-aminopropyl)-1,3-propanediamine; the fluorinated carboxylic acid ester in step a) is at least one of methyl heptafluorobutyrate, ethyl heptafluorobutyrate, methyl nonafluorovalerate, ethyl nonafluorovalerate, methyl undecanoate, ethyl perfluorooctanoate, and ethyl heptadecafluorononanoate; the reducing agent in step b) is at least one of lithium aluminum hydride, tetrahydrofuran borane complex, and sodium borohydride.

4. The oil-resistant, corrosion-resistant, and static-dissipating polyurea coating according to claim 1, characterized in that: The reaction in step a) is carried out at a temperature of 30℃ to 90℃; the reaction in step b) is carried out at a temperature of 5℃ to 80℃ for a reaction time of 4h to 48h.

5. The oil-resistant, corrosion-resistant, and static-dissipating polyurea coating according to any one of claims 1 to 4, characterized in that: The rust-preventive pigment and filler are at least one of aluminum tripolyphosphate, aluminum zinc phosphate, molybdate, and zinc phosphate; the conductive filler is conductive mica powder.

6. The oil-resistant, corrosion-resistant, and static-dissipating polyurea coating according to any one of claims 1 to 4, characterized in that: The dispersant is a polyurethane polymer dispersant; the defoamer is an organosilicon defoamer; the leveling agent is a fluorocarbon modified polyacrylate; the rheology modifier is micronized polyamide modified hydrogenated castor oil; the diluent is an ether ester solvent; and the dehydrating agent is a molecular sieve.

7. The oil-resistant, corrosion-resistant, and static-dissipating polyurea coating according to any one of claims 1 to 4, characterized in that: The aliphatic isocyanate curing agent is at least one of hexamethylene diisocyanate trimer, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and methylcyclohexyl diisocyanate.

8. A method for preparing an oil-resistant, corrosion-resistant, and static-dissipative polyurea coating as described in any one of claims 1 to 7, characterized in that, Includes the following steps: 1) Mix polyaspartic acid ester resin and fluorinated polyamine resin, then add dispersant, defoamer and leveling agent and mix well, then add rust-inhibiting pigments and fillers and conductive fillers and mix well, then add rheology modifier, diluent and dehydrating agent and mix well to obtain component A, and mix aliphatic isocyanate curing agent and diluent to obtain component B. 2) Mix component A and component B thoroughly to obtain an oil-resistant, corrosion-resistant, and static-dissipative polyurea coating.

9. An oil-resistant, corrosion-resistant, and static-dissipative polyurea coating as described in any one of claims 1 to 7, used for metal corrosion protection.

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