Preparation method and application of super-weather-resistant industrial heavy anti-corrosion coating

Abstract

The invention discloses a preparation method and application of a super-weather-resistant industrial heavy-duty anti-corrosion coating, and relates to the technical field of coatings, and the preparation method comprises the following preparation steps: step 1, formula preparation, step 2, raw material pre-dispersion treatment, step 3, filler functionalization treatment, step 4, self-repairing system preparation, and step 5, gradient curing. 35%-40% of bio-based epoxy resin, 25%-30% of organosilicone modified acrylate and 30%-35% of deionized water are added into a dispersion kettle in proportion, then a bionic antibacterial polypeptide coating, a waterborne polyurethane dispersion and a nano-clay modified leveling agent are added, interfacial tension is reduced through the surface activity effect, primary mixing of a main resin matrix and filler is achieved, and the main resin matrix and the filler are mixed uniformly; the subsequent grinding energy consumption is reduced, and the dispersion uniformity is improved, so that agglomeration caused by too high resin viscosity is avoided, and the salt fog resistance of the coating can be improved through the synergistic protection of the double microcapsules and the bionic antibacterial polypeptide coating.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and particularly relates to a preparation method and application of an ultra-weather-resistant industrial heavy-duty anti-corrosion coating. Background Art

[0002] Ultra-weather-resistant industrial heavy-duty anti-corrosion coatings achieve long-term protection in extreme environments through high-performance materials, composite coating structures, and strict process standards, and are high-end solutions in the field of industrial anti-corrosion.

[0003] In existing ultra-weather-resistant industrial heavy-duty anti-corrosion coatings, fluorocarbon resins (FEVE type), nano-graphene, rare earth cerium salts, etc. used in the coating formula are all high-value materials. In particular, the addition amount of graphene of 0.5% - 1% can significantly increase the cost. Moreover, the construction conditions for the coatings are relatively harsh. For example, the surface treatment needs to reach the ISO8501 1Sa2.5 sandblasting standard (roughness 40 - 70μm). If the substrate treatment does not meet the standard, it is easy to cause a decrease in the coating adhesion. This greatly reduces the practicality of ultra-weather-resistant industrial heavy-duty anti-corrosion coatings.

[0004] In summary, it is necessary to design a preparation method and application of an ultra-weather-resistant industrial heavy-duty anti-corrosion coating. Summary of the Invention

[0005] In order to overcome the above deficiencies, the present invention provides a preparation method and application of an ultra-weather-resistant industrial heavy-duty anti-corrosion coating.

[0006] The present invention realizes the above object through the following technical solutions: The research and development of an ultra-weather-resistant industrial heavy-duty anti-corrosion coating includes the following preparation steps: Step 1: Formula preparation. The formula includes a main resin matrix, fillers, and additives. The main resin matrix includes raw materials in the following proportions: 35% - 40% of bio-based epoxy resin and 25% - 30% of organosilicon-modified acrylate. The fillers include raw materials in the following proportions: 12% - 15% of basalt flakes, 2% - 3% of nano-titanium dioxide, and 0.5% - 1% of rare earth cerium salt / zinc-magnesium composite corrosion inhibitor. The additives include raw materials in the following proportions: 1.5% - 2% of double microcapsules, 0.3% - 0.5% of biomimetic antibacterial polypeptide coating, 5% - 8% of aqueous polyurethane dispersion, and 0.5% - 1% of nano-clay modified leveling agent; Step 2: Pre-dispersion treatment of raw materials to form a homogeneous main resin matrix, activate the active sites of the bio-based epoxy resin, realize the preliminary mixing of the main resin matrix and the fillers, reduce the subsequent grinding energy consumption, and improve the dispersion uniformity; Step 3: Functionalization treatment of fillers, respectively performing basalt flake treatment and nano-titanium dioxide treatment, improving the interfacial bonding force between the fillers and the main resin matrix, constructing a multi-level barrier network, and enhancing the barrier performance; Step 4: Preparation of self-healing system. Double microcapsules are prepared by the emulsion solvent evaporation method. The particle size of the microcapsules is controlled at 10 - 50 μm, with a proportion of 1.5%, achieving self-adaptive repair in a corrosive environment and extending the coating life. Step 5: Gradient curing. Gradient curing is carried out to form a gradient structure with a dense surface layer and a flexible bottom layer, balancing weather resistance and adhesion.

[0007] Preferably, the specific steps of step 2 are as follows: S21: Equipment selection. A high-speed disperser (rotation speed 1200 - 1800 r / min) is used, equipped with a serrated disc impeller to form a turbulent zone and enhance shear force. S22: Raw material mixing. 35% - 40% of bio-based epoxy resin (modified with cardanol), 25% - 30% of organosilicon-modified acrylate, and 30% - 35% of deionized water are added to the dispersion kettle in proportion. Subsequently, a bionic antibacterial polypeptide coating, aqueous polyurethane dispersion, and nano-clay modified leveling agent (such as BYK-190, with a proportion of 0.5% - 1%) are added. The interfacial tension is reduced through surface activity. At the same time, the temperature in the dispersion kettle is controlled at 25 - 35 °C to avoid resin degradation due to high temperature. The pre-dispersion time is 30 - 45 minutes until the system viscosity is stable (80 - 120 mPa·s), and the pre-dispersion index is that the fineness of the pre-dispersed slurry ≤ 50 μm (detection standard: GB / T 1724 - 2022).

[0008] Preferably, the specific steps of step 3 are as follows: S31: Basalt scale treatment. The basalt scales are soaked in an ethanol solution containing silane coupling agent for 30 minutes, and then dried at 60 °C. The concentration of the silane coupling agent is 5%. S32: Nano-titanium dioxide treatment. Nano-titanium dioxide and polydopamine are co-deposited to form an anti-ultraviolet antibacterial composite coating. S33: Dispersion strengthening. The modified filler and rare earth cerium salt corrosion inhibitor are mixed and ground in a sand mill until the fineness ≤ 15 μm. Zirconia beads with a particle size of 0.8 mm are used for grinding in the sand mill.

[0009] S34: Auxiliary dispersion. Ultrasonic assistance dispersion is used, and the ultrasonic frequency is 40 kHz.

[0010] Preferably, the specific steps of step 4 are as follows: S41: Double microcapsules are prepared by the emulsion solvent evaporation method. 2-mercaptobenzothiazole is dissolved in ethyl acetate and emulsified with a gelatin - arabic gum solution to form micro-droplets. The particle size of the microcapsules is 5 - 20 μm, the pH is adjusted to 4.5, and it is cured at a temperature of 50 °C for 2 hours to form a capsule with a wall thickness of 1 - 2 μm. S42. Intelligent response control: Add a pH-sensitive polymer (such as dimethylaminoethyl methacrylate), which is triggered to release in a corrosive microenvironment (pH > 9) (Performance indicators: microcapsule coating rate ≥ 90% (observed by SEM), inhibitor release efficiency > 80%).

[0011] Preferably, the specific steps of step five are as follows: S51. Pre-curing: Carry out curing for 1 hour at an ambient temperature of 80 °C to promote the preliminary cross-linking of HDI trimer and resin hydroxyl groups to form a flexible bottom layer; S52. Main curing: Carry out curing for 2 hours at an ambient temperature of 120 °C to make the fluorocarbon chain segments arranged orderly and construct a dense surface layer.

[0012] Preferably, in steps S51 and S52, infrared heating plates are used for heating and curing to achieve a temperature gradient in the thickness direction (the surface layer is 15 - 20 °C higher than the bottom layer), and at the same time, the ambient humidity < 60% to avoid coating defects (pinholes, fisheyes) caused by water vapor retention.

[0013] A coating prepared by the research and development of the above-mentioned ultra-weather-resistant industrial heavy-duty anti-corrosion coating is applied to offshore platforms, chemical pipelines and desert storage tanks.

[0014] The beneficial effects of the present invention are as follows: In the research and development and application technology of the ultra-weather-resistant industrial heavy-duty anti-corrosion coating: 35% - 40% of bio-based epoxy resin, 25% - 30% of organosilicon-modified acrylate and 30% - 35% of deionized water are added to the dispersion kettle in proportion, and then a bionic antibacterial polypeptide coating, a waterborne polyurethane dispersion and a nano-clay modified leveling agent are added. The interfacial tension is reduced through surface activity to achieve the preliminary mixing of the main resin matrix and the filler, reduce the subsequent grinding energy consumption, improve the dispersion uniformity, and thus avoid agglomeration caused by too high resin viscosity; The modified filler is mixed with a rare earth cerium salt inhibitor, and ground in a sand mill to a fineness ≤ 15 μm. Zirconia beads are used for grinding in the sand mill, and ultrasonic wave-assisted dispersion is combined. The ultrasonic wave frequency is 40 kHz, which can prevent particle secondary agglomeration; Basalt flakes replace graphene, and the proportion of bio-based resin is increased to 35%, reducing the raw material cost; The synergistic protection of double microcapsules and bionic antibacterial polypeptide coating can improve the salt spray resistance of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be described by way of examples and with reference to the accompanying drawings, wherein: Figure 1 is the process diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are all simplified schematic diagrams, only showing the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention.

[0017] As Figure 1 shown, the research and development of a super weather-resistant industrial heavy-duty anti-corrosion coating includes the following preparation steps: Step 1: Formula preparation. The formula includes a main resin matrix, fillers, and additives. The main resin matrix includes raw materials in the following proportions: 35%-40% bio-based epoxy resin and 25%-30% organosilicon-modified acrylate. The fillers include raw materials in the following proportions: 12%-15% basalt scales, 2%-3% nano-titanium dioxide, and 0.5%-1% rare earth cerium salt / zinc-magnesium composite corrosion inhibitor. The additives include raw materials in the following proportions: 1.5%-2% double microcapsules, 0.3%-0.5% bionic antibacterial polypeptide coating, 5%-8% aqueous polyurethane dispersion, and 0.5%-1% nano-clay modified leveling agent; Step 2: Pretreatment of raw material pre-dispersion to form a homogeneous main resin matrix, activate the active sites of the bio-based epoxy resin, achieve preliminary mixing of the main resin matrix and the fillers, reduce the subsequent grinding energy consumption, and improve the dispersion uniformity; Step 3: Functionalization treatment of the fillers, respectively perform basalt scale treatment and nano-titanium dioxide treatment to improve the interfacial bonding force between the fillers and the main resin matrix, construct a multi-level barrier network, and enhance the barrier performance; Step 4: Preparation of the self-healing system. Use the emulsion solvent evaporation method to prepare double microcapsules with a microcapsule particle size controlled at 10-50μm and a proportion of 1.5% to achieve self-adaptive repair in the corrosion environment and extend the coating life; Step 5: Gradient curing, perform gradient curing to form a gradient structure with a dense surface layer and a flexible bottom layer, and balance the weather resistance and adhesion.

[0018] Specifically, the second step includes the following specific steps: S21: Equipment selection. Use a high-speed disperser (rotation speed 1200-1800r / min), equipped with a serrated disc impeller to form a turbulent zone and enhance the shear force; S22. Raw material mixing: Add 35%-40% of bio-based epoxy resin (modified with cardanol), 25%-30% of organosilicon-modified acrylate, and 30%-35% of deionized water into the dispersion kettle according to the proportion. Then add the bionic antibacterial polypeptide coating, aqueous polyurethane dispersion, and nano-clay modified leveling agent (such as BYK190, with a proportion of 0.5%-1%). Reduce the interfacial tension through surface activity. At the same time, control the temperature in the dispersion kettle at 25-35°C to avoid resin degradation due to high temperature. The pre-dispersion time is 30-45 minutes until the system viscosity is stable (80-120 mPa·s). The pre-dispersion index is that the fineness of the slurry after pre-dispersion ≤ 50 μm (detection standard: GB / T 1724 - 2022).

[0019] Specifically, the specific steps of Step 3 are as follows: S31. Basalt scale treatment: Immerse the basalt scales in an ethanol solution containing silane coupling agent for 30 minutes, and then conduct a drying treatment at 60°C. The concentration of the silane coupling agent is 5%. S32. Nano-titanium dioxide treatment: Co-deposit nano-titanium dioxide and polydopamine to form an anti-ultraviolet antibacterial composite coating. S33. Dispersion strengthening: Mix the modified filler with rare earth cerium salt corrosion inhibitor, and grind it in a sand mill until the fineness ≤ 15 μm. Zirconia beads with a particle size of 0.8 mm are used for grinding in the sand mill. S34. Auxiliary dispersion: Use ultrasonic waves for auxiliary dispersion, and the ultrasonic frequency is 40 kHz.

[0020] Specifically, the specific steps of Step 4 are as follows: S41. Prepare double microcapsules by the emulsion solvent evaporation method: Dissolve 2-mercaptobenzothiazole in ethyl acetate, emulsify it with gelatin arabic gum solution to form micro-droplets. The particle size of the microcapsules is 5-20 μm. Adjust the pH to 4.5 and cure at a temperature of 50°C for 2 hours to form capsules with a wall thickness of 1-2 μm. S42. Intelligent response control: Add pH-sensitive polymers (such as poly(dimethylaminoethyl methacrylate)), and trigger release in a corrosive microenvironment (pH > 9) (performance indicators: microcapsule coating rate ≥ 90% (observed by SEM), corrosion inhibitor release efficiency > 80%).

[0021] Specifically, the specific steps of Step 5 are as follows: S51. Pre-curing: Conduct curing at an ambient temperature of 80°C for 1 hour to promote the preliminary cross-linking of HDI trimer and resin hydroxyl groups to form a flexible bottom layer. S52. Main curing: Conduct curing at an ambient temperature of 120°C for 2 hours to make the fluorocarbon chain segments arranged orderly and construct a dense surface layer.

[0022] Specifically, in the steps S51 and S52, an infrared heating plate is used for heating and curing to achieve a temperature gradient in the thickness direction (the surface layer is 15 - 20 °C higher than the bottom layer), and at the same time, the ambient humidity is < 60% to avoid coating defects (pinholes, fisheyes) caused by water vapor retention.

[0023] A coating prepared by researching and developing the above - mentioned ultra - weather - resistant industrial heavy - duty anti - corrosion coating is applied to offshore platforms, chemical pipelines and desert storage tanks.

[0024] Specific implementation case one: Anti - corrosion of steel structures on offshore platforms Application background: A deep - sea oil and gas drilling platform in the South China Sea is exposed to a high - salt - fog, strong - ultraviolet - ray and microbial - corrosion environment for a long time.

[0025] Coating system: Main resin: Bio - based epoxy resin (40%) + organosilicon - modified acrylate (30%) Functional fillers: Basalt flakes (12%), rutile - type nano - titanium dioxide (2.5%), zinc - magnesium composite corrosion inhibitor (0.8%) Self - repair system: Microcapsule - encapsulated 2MBT (1.2%), pH - sensitive triggered release Key steps in preparation: 1. Pre - dispersion stage: Mix the resin with deionized water (ratio 3:1), add dispersant BYK190 (0.8%), and pre - disperse at 1500 r / min for 40 minutes to form a homogeneous matrix with a viscosity of 100 mPa·s.

[0026] 2. Functionalization of fillers: After the basalt flakes are modified with KH560 silane coupling agent, they are ball - milled with nano - titanium dioxide to a fineness of ≤ 15 μm to improve the ultraviolet reflectivity (reflection wavelength < 380 nm).

[0027] 3. Gradient curing: Use an infrared heating plate for staged curing (pre - curing at 80 °C for 1 hour → main curing at 120 °C for 2 hours) to form a dense and hydrophobic surface structure (contact angle > 120°), and no corrosion propagation after more than 8000 hours of salt - spray testing.

[0028] Test results: Salt - spray resistance performance: Scratch expansion < 0.5 mm (ASTM B117 standard).

[0029] Microbial inhibition rate: Inhibition rate against sulfate - reducing bacteria > 90% (GB / T 21866 - 2008).

[0030] Specific implementation case two: Acid - and - alkali - resistant coating for chemical pipelines Application background: A pipeline for transporting acidic medium (pH 0.5 - 1.4) in a petrochemical plant needs to withstand a high temperature of 80 °C and H2S corrosion.

[0031] Coating system: Main resin: Fluorocarbon resin (FEVE type, 20%) + cardanol-modified epoxy resin (35%) Functional filler: Modified sericite powder (15%, improving anti-permeability), graphene (0.7%, enhancing conductivity) Curing agent: HDI trimer (molar ratio with hydroxyl group 1.3:1), suitable for low-temperature curing (10°C) Key steps in preparation: 1. Preparation of self-healing system: Encapsulate 2MBT by emulsion solvent evaporation method, with microcapsule particle size of 10 - 20μm, trigger release at pipeline stress cracks, and repair efficiency > 75%.

[0032] 2. Functionalization of fillers: After sericite powder is modified by (3-aminopropyl)trimethoxysilane, it is compounded with methacrylphenyl dicyandiamide to improve acid and alkali resistance (tolerant to pH 0.5 - 14).

[0033] 3. Spraying process: High-pressure airless spraying (film thickness error < 5μm), supporting cathodic protection system, designed service life ≥ 15 years.

[0034] Test results: Chemical medium resistance: Immerse in 80°C, 10% H2SO4 solution for 30 days, and the coating has no blistering or peeling (GB / T 1763 - 2020).

[0035] High-temperature tolerance: No cracking in thermal shock test (20 cycles) at 80°C (ISO 6270 - 2).

[0036] Specific implementation case three: Anti-erosion coating for desert storage tank Application background: A certain desert storage tank in Saudi Arabia needs to withstand day-night temperature difference (15°C to 60°C) and high-speed sand erosion.

[0037] Coating system: Main resin: Organosilicon-modified acrylate (50%) + fluorocarbon resin (15%) Functional filler: Nano-ceramic particles (8%, improving anti-erosion property), rare earth cerium salt (0.5%, inhibiting electrochemical corrosion) Additive: Hindered amine light stabilizer (HALS, 1.5%) + benzotriazole ultraviolet absorber (1%) Key steps in preparation: 1. Functionalization of fillers: Nano-ceramic particles are coated with titanate coupling agent (NDZ-201) and compounded and ground with basalt flakes to form a multi-level anti-erosion barrier.

[0038] 2. Gradient curing process: The surface curing temperature is 20°C higher than the bottom layer, forming a hardness gradient (surface hardness ≥ 4H, bottom layer flexibility > 2mm).

[0039] 3. Intelligent Monitoring: Embedded with fluorescent probes (accounting for 0.05%), it can monitor the coating damage in real time, and the maintenance cycle is extended to 8 years.

[0040] Test Results: Anti-scouring performance: Simulated sand grain impact (speed 20m / s) for 100 hours, and the coating wear rate < 0.1g / ㎡ (ASTM D96805).

[0041] Thermal cycle resistance: Cycled 50 times from 15°C to 60°C, and the coating showed no cracking (GB / T 1735 2023).

[0042] Based on the inspiration of the present invention, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A preparation method of an ultra-weather-resistant industrial heavy-duty anti-corrosion coating, characterized in that: It includes the following preparation steps: Step 1: Formula preparation. The formula includes a main resin matrix, fillers, and additives. The main resin matrix includes raw materials in the following proportions: 35%-40% bio-based epoxy resin and 25%-30% organosilicon-modified acrylate. The fillers include raw materials in the following proportions: 12%-15% basalt scales, 2%-3% nano-titanium dioxide, and 0.5%-1% rare earth cerium salt / zinc-magnesium composite corrosion inhibitor. The additives include raw materials in the following proportions: 1.5%-2% double microcapsules, 0.3%-0.5% bionic antibacterial polypeptide coating, 5%-8% aqueous polyurethane dispersion, and 0.5%-1% nano-clay modified leveling agent; Step 2: Pretreatment of raw material pre-dispersion to form a homogeneous main resin matrix, activate the active sites of the bio-based epoxy resin, achieve the preliminary mixing of the main resin matrix and the fillers, reduce the subsequent grinding energy consumption, and improve the dispersion uniformity; Step 3: Functionalization treatment of fillers. Basalt scale treatment and nano-titanium dioxide treatment are carried out respectively to improve the interfacial bonding force between the fillers and the main resin matrix, construct a multi-level barrier network, and enhance the barrier performance; Step 4: Preparation of self-healing system. Double microcapsules are prepared by the emulsification solvent evaporation method. The particle size of the microcapsules is controlled at 10-50μm, accounting for 1.5%, to achieve self-adaptive repair in the corrosion environment and extend the coating life; Step 5: Gradient curing is carried out to form a gradient structure with a dense surface layer and a flexible bottom layer, balancing weather resistance and adhesion.

2. The preparation method of a super weather-resistant industrial heavy-duty anti-corrosion coating according to claim 1, characterized in that: The specific steps of the said Step 2 include the following: S21: Equipment selection. A high-speed disperser is used, equipped with a sawtooth disc impeller to form a turbulent zone and enhance the shear force; S22: Raw material mixing. 35%-40% bio-based epoxy resin, 25%-30% organosilicon-modified acrylate, and 30%-35% deionized water are added to the dispersion kettle in proportion. Subsequently, a bionic antibacterial polypeptide coating, an aqueous polyurethane dispersion, and a nano-clay modified leveling agent are added. At the same time, the temperature in the dispersion kettle is controlled at 25-35°C, and the pre-dispersion time is 30-45 minutes.

3. The preparation method of a super weather-resistant industrial heavy-duty anti-corrosion coating according to claim 1, characterized in that: The specific steps of the said Step 3 are as follows: S31: Basalt scale treatment. The basalt scales are soaked in an ethanol solution containing silane coupling agent for 30 minutes, and then dried at 60°C. The concentration of the silane coupling agent is 5%; S32: Nano-titanium dioxide treatment. Nano-titanium dioxide and polydopamine are co-deposited to form an anti-ultraviolet antibacterial composite coating; S33: Dispersion strengthening. The modified fillers and rare earth cerium salt corrosion inhibitor are mixed, and ground in a sand mill to a fineness ≤15μm. Zirconia beads with a particle size of 0.8mm are used for grinding in the sand mill; S34: Auxiliary dispersion. Ultrasonic assistance dispersion is adopted, and the ultrasonic frequency is 40kHz.

4. The preparation method of a super weather-resistant industrial heavy-duty anti-corrosion coating according to claim 1, characterized in that: The specific steps of the said Step 4 are as follows: S41: Double microcapsules are prepared by the emulsification solvent evaporation method. 2-mercaptobenzothiazole is dissolved in ethyl acetate and emulsified with a gelatin arabic gum solution to form micro-droplets. The particle size of the microcapsules is 5-20μm, the pH is adjusted to 4.5, and cured at a temperature of 50°C for 2 hours to form a capsule with a wall thickness of 1-2μm; S42. Intelligent response control, adding pH-sensitive polymers, triggering release in a corrosive microenvironment (pH > 9).

5. The preparation method of a super weather-resistant industrial heavy-duty anti-corrosion coating according to claim 1, characterized in that: The specific steps of step five are as follows: S51. Pre-curing, curing for 1 hour at an ambient temperature of 80°C to promote the preliminary cross-linking of HDI trimer and resin hydroxyl groups to form a flexible bottom layer; S52. Main curing, curing for 2 hours at an ambient temperature of 120°C to arrange the fluorocarbon segments orderly and construct a dense surface layer.

6. The preparation method of a super weather-resistant industrial heavy-duty anti-corrosion coating according to claim 5, characterized in that: In steps S51 and S52, infrared heating plates are used for heating and curing, and at the same time, the ambient humidity < 60%.

7. A coating prepared by the preparation method of a super-weather-resistant industrial heavy-duty anti-corrosion coating according to claim 6 is applied to offshore platforms, chemical pipelines and desert storage tanks.

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