High-weather-resistant and high-impact-resistant repair coating for maritime work equipment and production process of high-weather-resistant and high-impact-resistant repair coating

Abstract

The invention relates to a high-weather-resistance and high-impact-resistance repair coating for maritime work equipment and a production process of the high-weather-resistance and high-impact-resistance repair coating. The coating is composed of 85% of an isocyanate resin preform, 1% of hydrophobic toner, 10% of ethyl acetate, 2.5% of hydrophobic fumed silica, 0.5% of bentonite, 0.5% of a leveling agent and 0.5% of a defoaming agent. The production process comprises the steps of pre-dispersion, high-speed dispersion, thixotropic adjustment, defoaming, filtering and the like. According to the invention, the aliphatic isocyanate resin is used as a matrix, and through scientific compounding of the functional auxiliary agents, the prepared paint film has extremely strong adhesive force, excellent impact resistance and flexibility, and excellent ultraviolet aging resistance and salt spray corrosion resistance. Meanwhile, the coating is good in construction performance, resistant to sagging, good in leveling performance, free of bubbles and especially suitable for efficient and long-acting protection and repair of local damage of maritime work equipment in the severe ocean environment.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of marine engineering protective materials, in particular to a high-weather-resistance and high-impact-resistance repair type coating for marine equipment and a production process thereof. BACKGROUND

[0002] Marine equipment such as offshore platforms, ships, port machinery and submarine pipelines are long-term exposed to extremely harsh corrosive environments with high salt, high humidity, strong ultraviolet radiation, dry-wet alternation and wave scouring. The surface coating of these equipment is prone to peeling, pulverization and cracking due to mechanical damage, corrosion medium penetration or aging, which leads to corrosion of the substrate and seriously affects the structural safety and service life of the equipment.

[0003] The existing repair coatings generally have the following problems: Insufficient weather resistance: prone to yellowing, loss of gloss and pulverization under strong ultraviolet radiation, which cannot provide long-term effective protection. This is mainly due to the poor ultraviolet aging resistance of the traditional coating resin system and the lack of effective ultraviolet shielding function of the pigment system.

[0004] Poor adhesion and impact resistance: insufficient resistance to dynamic load and accidental impact, and the repair layer is prone to cracking and peeling. Especially in marine environments, the coating needs to withstand frequent mechanical impact and temperature changes, and the traditional coating lacks flexibility.

[0005] Poor workability: poor leveling and sag resistance in harsh working conditions such as high humidity and low temperature, which easily produces bubbles and pinholes, affecting the density and appearance of the coating. This brings great difficulties to offshore construction operations.

[0006] Limited resistance to medium penetration: limited shielding effect on water and chloride ions and other corrosive media, which makes it difficult to effectively control the corrosion of the metal substrate under the coating. SUMMARY

[0007] Therefore, the purpose of the present application is to provide a high-weather-resistance and high-impact-resistance repair type coating for marine equipment and a production process thereof, which can improve weather resistance, impact resistance and workability, effectively solve the technical problems of peeling, pulverization and insufficient impact resistance of the coating of marine equipment in extreme corrosive environments.

[0008] The present application adopts the following method: a high-weather-resistance and high-impact-resistance repair type coating for marine equipment, which is composed of the following raw materials by weight percentage: Isocyanate resin preform: 75% - 90%; Hydrophobic toner: 0.5% - 3%; Ethyl acetate: 5% - 15%; hydrophobic fumed silica: 1.5% - 4%; bentonite: 0.1% - 1%; leveling agent: 0.1% - 1%; defoamer: 0.1% - 1%; and the sum of the weight percentages of each component is 100%.

[0009] Further, the following more preferably weight percentages of raw materials are used: isocyanate resin preform: 85%; hydrophobic toner: 1%; ethyl acetate: 10%; hydrophobic fumed silica: 2.5%; bentonite: 0.5%; leveling agent: 0.5%; defoamer: 0.5%.

[0010] Further, the isocyanate resin preform is an aliphatic polyurethane resin based on HDI or IPDI.

[0011] Further, the hydrophobic toner is a rutile titanium dioxide powder coated with a silicone or silane coupling agent.

[0012] Further, the bentonite is an organically modified bentonite.

[0013] Further, the leveling agent is a polyether-modified polydimethylsiloxane leveling agent.

[0014] Further, the defoamer is a non-silicone polymer defoamer.

[0015] A production process for producing the repair-type paint, comprising the following steps: Step S1, pre-dispersion: the formula amount of isocyanate resin preform, 70%-80% of the total amount of solvent ethyl acetate, hydrophobic toner, bentonite, leveling agent and defoamer are put into the dispersion equipment, stirred at 500-800 rpm for 15-20 minutes, and preliminary mixed and wetted; Step S2, high-speed dispersion: the speed is increased to 1200-1500 rpm, and the dispersion is continued for 25-35 minutes until the slurry fineness reaches ≤25 μm; Step S3, thixotropic adjustment: the speed is reduced to 400-600 rpm, the formula amount of hydrophobic fumed silica is slowly added, and the remaining ethyl acetate is used to clean the inner wall of the container and then put in, and the stirring is continued at this speed for 15-20 minutes to make the material fully and uniformly dispersed, forming a slurry with thixotropy; Step S4, defoaming and filtering: the speed is reduced to 200-300 rpm, vacuum degassing is carried out under the condition that the vacuum degree is not less than -0.095 MPa for 10-15 minutes, and then filtered through a 200-300 mesh filter to obtain the finished paint.

[0016] The application has the advantages that the application optimizes the raw material ratio and component characteristics, synergistically improves the ultraviolet resistance and mechanical impact resistance of the coating in a high-salt and high-humidity environment, improves the construction adaptability, and has the advantages of significantly enhancing the protection life of marine equipment and the on-site repair efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a process flow diagram of the application.

[0018] Figure 2 is a hardness test report of the application.

[0019] Figure 3 is a wear resistance test report of the application.

[0020] Figure 4 is an adhesion test report of the application.

[0021] Figure 5 is a tensile fracture test report of the application.

[0022] Figure 6 is a durability and weather resistance test report of the application. DETAILED DESCRIPTION

[0023] The technical solutions in the application will be described in detail below with reference to the drawings in the application. Obviously, the described embodiments are only some of the embodiments of the application, not all the embodiments. The components of the application described and shown in the drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the application. Based on the embodiments of the application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the application.

[0024] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. Meanwhile, in the description of the application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0025] The embodiments of the application propose a high-weather-resistant and high-impact-resistant repair type coating for marine equipment, which is composed of the following raw materials in weight percentage: Isocyanate resin preform: 75% - 90%; Hydrophobic toner: 0.5% - 3%; Ethyl acetate: 5% - 15%; Hydrophobic fumed silica: 1.5% - 4%; Bentonite: 0.1% - 1%; Leveling agent: 0.1% - 1%; Defoamer: 0.1% - 1%; and the sum of the weight percentages of the individual components is 100%.

[0026] In practical applications, the isocyanate resin preform can be understood as a prepolymer based on the reaction of polyisocyanate and polyol, which mainly serves as a film-forming material to provide the basic performance of the coating. Specifically, a prepolymer prepared by reacting aliphatic isocyanate with polyether or polyester polyol can be selected, such as a polyurethane system based on hexamethylene diisocyanate (HDI) or isophorone diisocyanate (IPDI), to achieve improved stability to ultraviolet radiation and mechanical properties.

[0027] Hydrophobic toner refers to pigment particles that have been surface-treated to reduce moisture absorption. Its main function is to enhance the stability of the coating in a humid environment. As a preferred embodiment, inorganic pigments such as red iron oxide or carbon black can be coated with fluorides or long-chain alkyl compounds to reduce moisture penetration.

[0028] Ethyl acetate, as an organic solvent, serves to adjust the viscosity of the coating to adapt to the construction conditions. Further, it can be compounded with other low-boiling ester solvents such as butyl acetate or acetone to optimize the volatilization rate and construction window period.

[0029] Hydrophobic fumed silica is an inorganic filler with nanoscale particle size, whose surface has been chemically modified to exhibit hydrophobic properties. Specifically, fumed silica treated with silane coupling agents can be selected to form a stable thixotropic network structure, thereby improving the anti-sagging performance of the coating.

[0030] Bentonite is a layered silicate mineral that mainly serves to thicken through interlayer cation exchange. For example, sodium-based or calcium-based bentonite can be used, and a small amount of polar activator such as sodium carbonate can be added to enhance its dispersibility and thickening efficiency.

[0031] The leveling agent serves to reduce the surface tension of the coating to promote uniform spreading. In practical applications, non-ionic surfactants or fluorocarbon compounds can be used as alternatives to reduce surface defects and improve the appearance quality of the coating.

[0032] The defoamer functions to eliminate air bubbles generated during the mixing and application of the coating. As a preferred embodiment, mineral oil-based or polyether-modified compounds can be used to achieve rapid bubble breaking and long-term bubble suppression.

[0033] The innovation of the present application is that through the synergistic design of specific components, the comprehensive performance problem of marine equipment repair coating in extreme environments such as high salt, high humidity, strong ultraviolet radiation and sea wave scouring is solved. Compared with the prior art, the coating significantly enhances the water resistance and construction adaptability of the coating by introducing key components such as hydrophobic toner and hydrophobic fumed silica, and the high proportion of isocyanate resin preform ensures the balance of basic weather resistance and mechanical strength. Thus, the surface of the marine equipment is effectively protected for a long time.

[0034] The working principle of the embodiment of the present application is as follows: A high-weather-resistant and high-impact-resistant repair coating for marine equipment, the core of which is to realize the adaptability to extreme environments through the synergistic effect of specific components. The isocyanate resin preform as the main film-forming material provides the basic performance of the coating in the range of 75% to 90% by weight, wherein the resin type has excellent ultraviolet stability, which can effectively resist the aging phenomenon caused by strong ultraviolet radiation, and its molecular structure endows the coating with high toughness to absorb mechanical impact energy, thereby coping with the damage caused by sea wave scouring and dynamic load. The hydrophobic toner is introduced in a proportion of 0.5% to 3%, based on its surface hydrophobic treatment characteristics, it can actively repel the penetration of water and corrosive media, avoiding the degradation problem caused by moisture absorption, and further enhancing the long-term protection ability of the coating. Ethyl acetate as a solvent is controlled in the range of 5% to 15% by weight, which is used to adjust the viscosity of the coating to adapt to harsh construction conditions such as high humidity and low temperature, and to ensure that there will be no defects caused by excessive solvent during the drying process. Hydrophobic fumed silica is added in the range of 1.5% to 4%, its hydrophobic surface structure not only improves the overall water resistance of the coating, but also forms a stable thixotropic network to prevent the coating from sagging on vertical surfaces, thereby ensuring uniform coating effect during construction. Bentonite is used in a trace amount of 0.1% to 1%, which maintains the stability of the coating during storage through its thickening mechanism, avoids pigment sedimentation, and ensures the consistency of each construction. The leveling agent is optimized in the range of 0.1% to 1% to improve the spreading behavior of the coating, reduce surface defects such as orange peel, and improve the density and appearance quality of the coating. The defoaming agent also plays a role in the range of 0.1% to 1%, by eliminating the bubbles generated during the mixing process, avoiding the formation of pinholes, thereby strengthening the shielding effect of the coating on water, chloride ions and other corrosive media. The components cooperate with each other in the specified proportion range, and solve the problems of insufficient weather resistance, poor adhesion and impact resistance, poor construction performance and poor medium penetration resistance of marine equipment repair coating in extreme harsh environments such as high salt, high humidity, strong ultraviolet radiation and sea wave scouring.

[0035] The present application further proposes to be composed of the following more preferred raw materials by weight percentage: Isocyanate resin preform: 85%; Hydrophobic color powder: 1%; Ethyl acetate: 10%; Hydrophobic fumed silica: 2.5%; Bentonite: 0.5%; Leveling agent: 0.5%; Defoaming agent: 0.5%.

[0036] Specifically, the isocyanate resin preform refers to an aliphatic polyurethane resin based on HDI or IPDI, which can be realized by using polyurethane resins with different molecular weights and functionalities, aiming to provide the basic strength and weather resistance of the coating film. The hydrophobic color powder can be understood as rutile titanium dioxide coated with a silicone or silane coupling agent, which can be realized by different surface treatment processes, aiming to ensure color stability while not affecting the overall protective performance of the coating. Ethyl acetate as a solvent component can be realized by selecting ester solvents with different purity and evaporation rates, aiming to optimize the construction performance and leveling of the coating. Hydrophobic fumed silica refers to nanoscale silica treated with a hydrophobic surface, which can be realized by using fumed silica with different specific surface areas and surface modification degrees, aiming to provide appropriate thixotropy and water resistance. Bentonite can be understood as organically modified bentonite, which can be realized by different organic intercalation modification techniques, aiming to improve the rheological properties of the coating. The leveling agent refers to a polyether-modified polydimethylsiloxane leveling agent, which can be realized by using siloxane compounds with different molecular weights and modification degrees, aiming to promote uniform distribution of the coating. The defoaming agent refers to a non-silicone polymer defoaming agent, which can be realized by selecting polymers with different chemical structures and molecular weights, aiming to effectively eliminate bubbles.

[0037] Specifically, the above scheme precisely defines the weight percentage of each component, so that a stable interaction relationship is formed between each raw material. The isocyanate resin preform provides basic mechanical strength and weather resistance at a higher proportion, while cooperating with an appropriate amount of ethyl acetate to ensure good construction leveling. The hydrophobic color powder is added at a lower proportion, which meets the coloring demand and avoids affecting the overall hydrophobic performance. Hydrophobic fumed silica and bentonite work together to form a stable thixotropic system, effectively preventing the settling of the coating during storage. The reasonable proportion of leveling agent and defoaming agent significantly improves the surface performance of the coating, reducing the occurrence of defects such as pinholes. This precise formulation design is particularly suitable for high-salt and high-humidity environments of marine equipment, which can effectively improve the performance indicators of the repair coating.

[0038] By the above technical scheme, the paint formula is further optimized on the basis of a wide range of proportions, ensuring the stable performance of the paint in extreme corrosion environments, especially achieving a better balance in terms of weather resistance, impact resistance, application performance, and medium penetration resistance.

[0039] The application further proposes that the isocyanate resin preform is an aliphatic polyurethane resin based on HDI or IPDI.

[0040] Specifically, the isocyanate resin preform refers to the key raw material as the core film-forming component of the paint, which can be achieved by using an aliphatic polyurethane resin based on HDI or IPDI. In practical applications, HDI and IPDI, as typical representatives of aliphatic isocyanates, can form polyurethane resins with excellent ultraviolet resistance and yellowing resistance, thereby avoiding the defect of aromatic types that are easily degraded under strong light. The purpose of introducing this feature is to significantly improve the weather resistance of the repair type paint, while enhancing the toughness and impact resistance of the coating to adapt to extreme corrosion and mechanical damage in marine environments.

[0041] In detail, the above scheme solves the problems of insufficient weather resistance and impact resistance by limiting the specific type of isocyanate resin preform. The aliphatic polyurethane resin based on HDI or IPDI not only has excellent ultraviolet resistance, but also effectively reduces yellowing and loss of luster caused by strong ultraviolet radiation, thereby ensuring that the coating maintains stable appearance and performance during long-term use. In addition, the aliphatic structure gives the coating better toughness, making it less prone to cracking or peeling under high sea wave scouring or dynamic load, and overall improving the adaptability of the repair type paint to marine corrosion environments. On this basis, combined with the reasonable proportioning of the isocyanate resin preform and other components, the mechanical strength and durability of the paint are further optimized, forming a complete technical system to better meet the repair needs of marine equipment in extreme harsh environments.

[0042] The application further proposes that the hydrophobic toner is a rutile titanium dioxide powder coated with an organic silicon or silane coupling agent.

[0043] Among them, the hydrophobic toner refers to a toner material that enhances its hydrophobic properties through specific treatment, which can be achieved by coating the rutile titanium dioxide powder with an organic silicon or silane coupling agent. In practical applications, rutile titanium dioxide is chosen as the base material due to its high weather resistance and chemical stability, which aims to effectively resist strong ultraviolet radiation and environmental erosion, and further improve the hydrophobic properties of the toner through the coating treatment of the organic silicon or silane coupling agent, thereby better repelling moisture and corrosive media and reducing the risk of coating yellowing and powdering.

[0044] Specifically, the above technical solution solves the problem of insufficient hydrophobicity of existing toner by limiting the specific implementation of hydrophobic toner, thereby improving the weather resistance and stability of the coating. In a high-salt, high-humidity, and strong ultraviolet environment, the rutile titanium dioxide coated with organosilicon or silane coupling agent can significantly improve the overall performance of the coating. On the one hand, rutile titanium dioxide itself has excellent weather resistance and anti-aging ability, and can maintain color stability in extreme environments. On the other hand, the coating treatment of organosilicon or silane coupling agent gives the toner stronger hydrophobic properties, allowing it to effectively prevent water penetration in high humidity conditions, thereby extending the service life of the coating. In addition, this treatment method works together with other components such as isocyanate resin preform and ethyl acetate to ensure that the coating exhibits good leveling, anti-sagging, and shielding effect against corrosive media during construction and use, thereby forming a more dense and long-acting protective coating.

[0045] In summary, through the above technical solution, not only the weather resistance and appearance stability of the coating are improved, but also the comprehensive protection performance in harsh environments is enhanced, providing a more reliable repair solution for marine equipment.

[0046] The present application further proposes that the bentonite is an organically modified bentonite.

[0047] Among them, bentonite refers to a kind of aluminosilicate mineral with layered structure, which can be realized by using organically modified bentonite with organic cation or organic molecule intercalation. In practical application, organically modified bentonite is treated by surfactant, which exhibits excellent dispersibility and compatibility in organic solvent system, and the purpose is to solve the agglomeration problem caused by unmodified bentonite in the coating system, thereby improving the construction performance and coating quality of the coating.

[0048] Specifically, the above scheme significantly improves the rheological properties of the coating by introducing organically modified bentonite. During the preparation of the coating, organically modified bentonite can be uniformly dispersed in the organic solvent system composed of isocyanate resin preform, ethyl acetate and other components, avoiding the problem of poor leveling and anti-sagging caused by poor dispersion of traditional unmodified bentonite. At the same time, this scheme works together with components such as hydrophobic fumed silica and leveling agent to effectively reduce the generation of defects such as bubbles and pinholes, ensuring the uniformity and good thixotropy of the coating. In addition, the introduction of organically modified bentonite also enhances the adaptability of the coating to harsh working conditions such as high humidity and low temperature, further improving the construction performance and density of the coating.

[0049] Through the above technical solution, not only the problem of poor dispersion of bentonite in the coating is solved, but also the performance of the overall coating system is optimized, providing a more reliable repair solution for marine equipment.

[0050] The application further proposes that the leveling agent is a polyether-modified polydimethylsiloxane leveling agent.

[0051] The leveling agent refers to an additive that can reduce the surface tension of the coating and improve the flowability and spreadability of the coating. In practical applications, the polyether-modified polydimethylsiloxane leveling agent combines the excellent compatibility of the polyether group and the surface activity characteristics of the polydimethylsiloxane. By adjusting the ratio of the polyether segment and the siloxane segment, different leveling effects can be achieved. The purpose of introducing the leveling agent is to solve the problems of insufficient leveling and easy formation of bubbles and pinholes caused by high humidity, low temperature and other harsh working conditions during the coating construction process.

[0052] Specifically, the above-mentioned scheme effectively improves the construction performance of the coating in complex environments by limiting the specific type of the leveling agent to polyether-modified polydimethylsiloxane. The leveling agent can quickly migrate to the surface of the coating during the coating process, reducing the surface tension and promoting the uniform flow and spread of the coating. At the same time, due to its special molecular structure design, it can reduce bubble retention and inhibit the formation of pinholes, ensuring that the coating has a smooth and dense appearance. In addition, this leveling agent has good compatibility with other components such as isocyanate resin preforms and hydrophobic toner, and can fully integrate into the system during the dispersion and mixing stage, further enhancing the overall stability of the coating.

[0053] In summary, through the above technical scheme, not only the problem of poor leveling during the coating construction process is solved, but also the compactness and appearance quality of the coating are significantly improved, providing more reliable protection performance for marine equipment.

[0054] The application further proposes that the defoaming agent is a non-silicone polymer defoaming agent.

[0055] Specifically, the non-silicone polymer defoaming agent refers to a polymer type defoaming additive that does not contain silicone components. It can be realized by polyether modification, fatty alcohol derivatives or mineral oil-based polymers, etc. The purpose is to avoid the surface tension imbalance problem that may be caused by silicone substances, thereby reducing the formation of pinholes on the coating surface and improving the bubble elimination ability of the coating during the dispersion and construction stages.

[0056] In detail, in the preparation process of the repair coating, the non-silicone polymer defoamer is used in combination with the isocyanate resin preform, hydrophobic toner and other additives, which can effectively reduce the surface tension in the system, and avoid coating defects caused by silicone residues. Especially in harsh construction environments such as high humidity or low temperature, this kind of defoamer shows excellent adaptability, can significantly reduce bubble residues, and ensure the density and appearance quality of the coating. In addition, due to the good compatibility of the non-silicone polymer defoamer with hydrophobic fumed silica and leveling agent and other components, the thixotropic adjustment and leveling performance of the entire coating system are optimized, thereby further enhancing the reliability and durability of the repair coating in extreme environments.

[0057] Referring to Figure 1 In another embodiment, the application also discloses a production process for producing a high-weather-resistant and high-impact-resistant repair coating for marine equipment, comprising the following steps: Step S1, pre-dispersion: the formula amount of isocyanate resin preform, 70%-80% of the total amount of ethyl acetate, hydrophobic toner, bentonite, leveling agent and defoamer are put into a dispersion device, and stirred at a speed of 500-800 rpm for 15-20 minutes for preliminary mixing and wetting; Step S2, high-speed dispersion: the speed is increased to 1200-1500 rpm, and the dispersion is continued for 25-35 minutes until the slurry fineness reaches ≤25 μm; Step S3, thixotropic adjustment: the speed is reduced to 400-600 rpm, the formula amount of hydrophobic fumed silica is slowly added, and the remaining ethyl acetate is used to clean the inner wall of the container and then put into the container, and the stirring is continued at this speed for 15-20 minutes to make the material fully and uniformly dispersed, forming a slurry with thixotropy; Step S4, defoaming and filtering: the speed is reduced to 200-300 rpm, vacuum degassing is carried out under the condition that the vacuum degree is not less than-0.095 MPa for 10-15 minutes, and then filtered through a 200-300 mesh filter to obtain the finished coating.

[0058] The core innovation of the embodiment is that the dispersion, mixing and defoaming process in stages is combined with the synergistic design of specific components, thereby solving the problems of insufficient weather resistance, poor adhesion, poor construction performance and poor medium penetration resistance of the marine equipment repair coating caused by improper process in the production process, and achieving the effect of significantly improving the comprehensive performance of the coating. Specifically, in the pre-dispersion stage, by controlling the stirring speed in the range of 500-800 rpm and the stirring time of 15-20 minutes, the preliminary wetting of the isocyanate resin preform and the hydrophobic color powder and other components is ensured, the agglomeration problem caused by high-speed shearing is avoided, a uniform basis for subsequent dispersion is laid, and then the coating adhesion and leveling during construction are improved. In the high-speed dispersion stage, by increasing the speed to 1200-1500 rpm and continuing for 25-35 minutes, the precise refinement of the slurry fineness ≤25 μm is realized, the full dispersion of the additives such as bentonite and leveling agent is ensured, and the micro defects are reduced, thereby enhancing the impact resistance of the coating against wave erosion and the barrier ability against chloride ion penetration. In the thixotropic adjustment stage, by reducing the speed to 400-600 rpm and slowly adding hydrophobic fumed silica, the thixotropic structure is avoided from being destroyed by high-speed shearing, and the remaining ethyl acetate is used to clean the inner wall of the container to ensure complete transfer of the material, so that the hydrophobic fumed silica is uniformly dispersed to form a thixotropic slurry, and the anti-sagging property and construction adaptability of the coating in a high-humidity environment are significantly improved. In the defoaming and filtering stage, by using a low speed of 200-300 rpm and a vacuum degree of not less than -0.095 MPa for defoaming treatment, the micro bubbles are completely eliminated, and the impurities are removed by filtering through a 200-300 mesh filter to ensure that the coating is dense and free of pinholes, and finally the high weather resistance and long-term corrosion protection are realized.

[0059] In practical application, the production process can effectively cope with extreme harsh environments such as high salt, high humidity, strong ultraviolet radiation and wave erosion, and provide long-term effective protection for the surface of marine equipment, significantly prolonging the service life of the equipment and improving its safety.

[0060] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below in combination with specific examples and test data. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the protection scope of the present application.

[0061] Example 1: Preparation of a gray high-weather-resistant high-impact-resistant repair coating The raw materials are prepared according to the following weight percentages: HDI-based isocyanate resin preform 85%, hydrophobic rutile titanium dioxide (treated with silane coupling agent) 1%, ethyl acetate 10%, hydrophobic fumed silica (specific surface area 200±25 m 22.5% ( / g), 0.5% organic modified bentonite, 0.5% polyether modified polydimethylsiloxane leveling agent, and 0.5% non-silicone polymer defoamer.

[0062] The preparation process steps are as follows: Pre-dispersion: In a 500L high-speed dispersion vessel, add 85kg of isocyanate resin preform, 7kg of ethyl acetate, 1kg of hydrophobic rutile titanium dioxide, 0.5kg of organobentonite, 0.5kg of leveling agent, and 0.5kg of defoamer. Stir at 600 rpm for 18 minutes.

[0063] High-speed dispersion: Increase the rotation speed to 1300 rpm and disperse at high speed for 30 minutes. Take a sample and test the fineness of the slurry. It is 20μm.

[0064] Thixotropic adjustment: Reduce the rotation speed to 500 rpm, slowly and evenly add 2.5 kg of hydrophobic fumed silica, then clean the feeding container with the remaining 3 kg of ethyl acetate and add it to the reactor, and continue stirring for 18 minutes.

[0065] Defoaming and filtration: Finally, reduce the rotation speed to 250 rpm and turn on the vacuum system (vacuum degree -0.096 MPa) for 12 minutes to defoam. After defoaming, discharge through a 250-mesh filter cloth and package to obtain the finished product component A (corresponding to product type FQR405 in the test report).

[0066] Example 2: Performance Testing and Result Analysis The coating obtained in Example 1 (corresponding to FQR405) was prepared and its performance was tested according to national standards and industry-standard methods. The results were compared with relevant commercially available or comparative samples (such as FQR011 and FQR015). Key data are as follows: 1. Mechanical properties Please see Figure 4 As shown, adhesion: The adhesion was tested using the pull-off method according to GB / T 5210-2006. Figure 1 As shown in the test report (No. SYS20250516), the adhesion of this product to sandblasted steel plates reaches 18.85 MPa to 22.20 MPa (when using a primer). The failure modes are mostly cohesive failure or primer layer failure, indicating that its bonding strength with the metal substrate is extremely strong, far exceeding that of conventional repair coatings. On concrete substrates, the adhesion can reach over 5.72 MPa, and the failure occurs inside the concrete, indicating that its adhesion to the fragile substrate is also better than the strength of the substrate itself.

[0067] Please see Figure 5Hardness and toughness: According to GB / T 531.1-2008, the paint film of the present application has a Shore A hardness of 94 (Test Report No. JD20250040), showing high rigidity. Meanwhile, according to GB / T 528-2009, the tensile strength is as high as 38.8 MPa, and the elongation at break is as high as 419% (Test Report No. JD20250038). This unique combination of "high hardness, high strength, and high elongation" endows the paint film with excellent impact resistance and flexibility, which can effectively absorb and disperse external mechanical impact energy.

[0068] Wear resistance: According to GB / T 1768-2006, the mass loss of the present application is only 30.5-34.4 mg under the condition of 1000 revolutions / 1000 g (Test Report No. JD20250039), which is significantly lower than that of comparative samples FQR011 (55.5-57 mg) and FQR015 (41.0-51.9 mg), proving that it has excellent anti-wear ability and is suitable for marine environments with sand and water flow erosion.

[0069] Please refer to Figure 6 As shown below, the data comes from the 4200-hour (about 175 days) continuous accelerated aging test report (Report No. ZDT2510A8257) issued by a national accredited laboratory, which is conducted in accordance with the highest performance standard for marine building protective coating systems (GB / T 31415-2015), and the results fully verify the long-life potential of the present application: Wet heat resistance test (4200h): According to GB / T 1740-2007, the coating surface is free of blistering, cracking, peeling, color change, and loss of gloss. This proves that the coating has excellent stability in high-humidity and high-heat environments, and has strong resistance to water vapor penetration and thermal stress damage.

[0070] Artificial climate aging test (4200h, equivalent to years of outdoor exposure): According to GB / T 1865-2009 (filtered xenon arc radiation), the coating surface is free of blistering, cracking, peeling, color change, and loss of gloss. This directly confirms that the system based on aliphatic isocyanate as the base material has top-level UV aging resistance, fundamentally solving the traditional problems of coating powdering, yellowing, and loss of gloss.

[0071] Salt spray cycle test (4200h): According to GB / T 31588.1-2015 (wet / dry / wet cycle), the coating surface is free of cracking, delamination, blistering, powdering, and color change. This test simulates the harsh marine splash zone corrosion environment, and the results show that the coating has a strong shielding effect against chloride ion penetration.

[0072] Salt water immersion test (4200h): According to GB / T 30648.1-2014, after long-term immersion in salt water, the coating surface has no cracking, blistering, peeling, no color change and loss of luster. Further prove that the paint film is dense and complete, and has excellent resistance to penetration.

[0073] Comprehensive cycle aging test (4200h, 25 cycles): According to GB / T 31415-2015 procedure a (combined with ultraviolet, salt spray, low temperature, dry-wet cycle), the coating surface has no blistering, cracking, peeling, no powdering, only slight color change and loss of luster. This test is the most comprehensive test closest to the harsh environment of real sea, and the results fully meet the technical requirements of the highest grade protective coating.

[0074] Example 3: Application example The coating on the weld of a certain offshore platform steel structure was damaged by collision, and the following process was used for repair: Surface treatment: The damaged area was sandblasted to achieve Sa2.5 level and St3 level of cleanliness.

[0075] Primer coating: One coat of matching epoxy primer was applied.

[0076] Repair construction: The coating obtained in Example 1 was stirred uniformly, and 2 coats were sprayed on the primer using a high-pressure airless spraying equipment, with a total dry film thickness of 1500 μm.

[0077] Curing: The ambient temperature was 15-25℃, the relative humidity was <80%, and the coating was used after curing for 72 hours.

[0078] The repaired area had a smooth and flat paint film with strong adhesion. After 12 months of marine environment tracking inspection, the repair coating had no blistering, no rust, no cracking, and the wear-resistant area had no obvious wear, showing excellent long-term protection effect.

[0079] The comparative example used a common aromatic polyurethane elastic coating for repair under the same conditions. After 6 months, it was found that the coating surface had obvious yellowing, and fine cracks appeared at the edge of the splash zone, and the adhesion test value decreased to below 8 MPa. This highlights the comprehensive advantages of high weather resistance, high adhesion and mechanical properties obtained by formula optimization based on the aliphatic system of the present application.

[0080] In summary, the repair coating provided by the present application successfully solves the technical problems of high weather resistance, high adhesion, high impact resistance and high wear resistance required for repair coating of marine equipment by compounding specific proportions of aliphatic isocyanate resin, hydrophobic functional materials (color powder, fumed silica) and high-efficiency additives, and combining with specific production process. The measured data fully proves the advancement and beneficial effects of the technical scheme.

[0081] The following is the adhesion test table of the three coatings.

[0082] Conclusion: (1) The adhesion of three coatings (with the polyurethane primer we provide) to concrete is greater than 5-6 MPa, and the failure is inside the cementitious surface. The adhesion of FQR coatings to concrete depends largely on the quality of the concrete.

[0083] (2) The adhesion of the coatings themselves is close between 011 and 405, and the data should be 26-28 MPa considering the sample preparation. The adhesion of 015 is lower due to its lower strength, and should be 10-12 MPa.

[0084] With the epoxy primer we provide, the epoxy primer is not failed to the substrate surface, indicating that its adhesion should be above 20-22 MPa. The use of high-performance epoxy primer with 011 and 015 can improve the overall performance.

[0085] The above only describes the embodiments of the present application and is not used to limit the protection scope of the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A high weathering and high impact resistant repair type coating for marine equipment, characterized in that, consists of the following raw materials by weight percentage: Isocyanate resin preform: 75% - 90%; Hydrophobic toner: 0.5% - 3%; Ethyl acetate: 5% - 15%; Hydrophobic fumed silica: 1.5% - 4%; Bentonite: 0.1% - 1%; Leveling agent: 0.1% - 1%; Defoaming agent: 0.1% - 1%; and the sum of the weight percentages of each component is 100%.

2. A high weather resistant and high impact resistant repair type coating for marine equipment according to claim 1, characterized in that: consists of the following more preferred raw materials by weight percentage: Isocyanate resin preform: 85%; Hydrophobic toner: 1%; Ethyl acetate: 10%; Hydrophobic fumed silica: 2.5%; Bentonite: 0.5%; Leveling agent: 0.5%; Defoaming agent: 0.5%.

3. A high weather resistant and high impact resistant repair type coating for marine equipment according to any one of claims 1-2, characterized in that: The isocyanate resin preform is an aliphatic polyurethane resin based on HDI or IPDI.

4. The high-weathering and high-impact repair coating for marine equipment according to any one of claims 1-2, characterized in that: The hydrophobic toner is a rutile titanium dioxide coated with a silicone or silane coupling agent.

5. The high-weathering and high-impact repair coating for marine equipment according to any one of claims 1-2, characterized in that: The bentonite is an organically modified bentonite.

6. A high-weathering, high-impact, repair-type coating for marine equipment as claimed in any one of claims 1 to 2, characterised in that: The leveling agent is a polyether-modified polydimethylsiloxane leveling agent.

7. A high-weathering, high-impact, repair-type coating for marine equipment as claimed in any one of claims 1 to 2, characterised in that: The defoaming agent is a non-silicone polymer defoaming agent.

8. A production process for producing the repair coating according to any one of claims 1 to 7, characterized in that The method comprises the following steps: Step S1, pre-dispersion: the formula amount of isocyanate resin preform, solvent accounting for 70%-80% of the total amount of ethyl acetate, hydrophobic toner, bentonite, leveling agent and defoaming agent are put into a dispersion device, stirred at a speed of 500-800 rpm for 15-20 minutes, and preliminary mixing and wetting are carried out; Step S2, high-speed dispersion: the speed is increased to 1200-1500 rpm, and the dispersion is continued for 25-35 minutes until the slurry fineness reaches ≤25 μm; Step S3, thixotropy adjustment: the speed is reduced to 400-600 rpm, the formula amount of hydrophobic fumed silica is slowly added, and the remaining ethyl acetate is used to clean the inner wall of the container and then put in, and the stirring is continued at this speed for 15-20 minutes to make the material fully and uniformly dispersed, forming a slurry with thixotropy; Step S4, defoaming and filtering: the speed is reduced to 200-300 rpm, vacuum degassing is carried out under a vacuum degree not less than -0.095 MPa for 10-15 minutes, and then filtered through a 200-300 mesh filter to obtain the finished paint.

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