An abrasion-resistant industrial coating and method of making the same

Abstract

The present application relates to a kind of abrasion-resistant industrial coating and its manufacturing method, belong to the field of coating technology, coating component includes modified epoxy resin liquid, modified phenolic resin liquid, boron zirconium powder, silicon carbide powder, hexagonal boron nitride powder, flaky zinc-aluminum alloy powder, methyl hexahydrophthalic anhydride, hexamethoxymethyl melamine etc.Modified epoxy resin liquid is hydrogenated bisphenol A type epoxy resin by hydroxyl end-capped trifluoropropyl methyl polysiloxane modification obtains;Modified phenolic resin liquid is linear phenolic resin etherization, and mixed with soluble polyimide powder to obtain.The present application uses the composite base material formed by hydrogenated epoxy resin and phenolic resin, combines silicon fluoride modification and polyimide enhancement technology, so that coating has the strong adhesion of epoxy resin and the high temperature resistance of phenolic resin, can still maintain the chemical bonding force with metal base material under high temperature environment, cooperates with functional filler, and the increment is low after temperature resistance, forms the abrasion-resistant system of " hard skeleton + soft lubrication ", and is corrosion resistant.

Description

Technical Field

[0001] This invention belongs to the field of coating technology, specifically relating to a wear-resistant industrial coating and its manufacturing method. Background Technology

[0002] In industrial production, mechanical equipment typically requires coatings for corrosion and wear resistance. The performance of wear-resistant industrial coatings depends on the synergistic design of resin base materials, functional fillers, and additives. For example, the resin base material, as the film-forming substance, determines the basic properties of the coating: epoxy resins, due to the chemical bonding force between the epoxy groups in their molecular structure and the metal substrate, provide excellent adhesion and chemical stability; polyurethane resins, by adjusting the ratio of soft / hard segments, balance the hardness and flexibility of the coating, making them suitable for dynamic friction conditions; fluorocarbon resins, with their high bond energy characteristics of CF bonds, endow the coating with outstanding weather resistance and chemical inertness.

[0003] Functional fillers are key components for improving coating performance. Wear-resistant fillers, such as ceramic particles like alumina (Al2O3) and silicon carbide (SiC), utilize their high hardness to form an anti-wear skeleton structure in the coating. Corrosion-resistant fillers, represented by metal powders such as zinc powder and aluminum powder, preferentially undergo oxidation reactions in corrosive environments through the sacrificial anode principle, consuming corrosive media and protecting the metal substrate. Nanoscale fillers, such as nano-titanium dioxide (TiO2) and graphene, can significantly improve the physical barrier properties of the coating and slow down the diffusion rate of corrosive media due to their high specific surface area and layered structure.

[0004] Furthermore, the additive system enhances performance by optimizing coating application and structure. Dispersants prevent filler agglomeration, ensuring coating uniformity; curing agents cross-link with resin to form a dense network structure, improving hardness and chemical stability; rheology modifiers adjust coating viscosity to suit different application processes such as spraying and brushing.

[0005] Existing technologies have achieved synergistic improvements in abrasion and corrosion resistance through component compounding and process optimization. However, under extreme conditions such as high temperatures and strong erosion, coatings still face challenges such as decreased adhesion and insufficient temperature resistance, which affect corrosion and abrasion resistance. Therefore, it is necessary to design the overall performance of the coating in conjunction with the operating temperature environment to ensure that the coating maintains good performance in harsh environments and further overcome performance bottlenecks. Summary of the Invention

[0006] To address the poor stability of existing coatings at high temperatures, which affects adhesion, corrosion resistance, and abrasion resistance, thus reducing their protective properties, this invention provides a wear-resistant industrial coating and its manufacturing method. It utilizes a composite base material formed from hydrogenated epoxy resin and phenolic resin, combined with silicone-fluorine modification and polyimide reinforcement technology. This allows the coating to possess both the strong adhesion of epoxy resin and the high-temperature resistance of phenolic resin, maintaining chemical bonding with the metal substrate even at high temperatures. Wear-resistant fillers construct an anti-wear skeleton, which, combined with the lubricating effect of hexagonal boron nitride, results in low initial wear resistance loss and low post-temperature increase, forming a "hard skeleton + soft lubrication" wear-resistant system. Flake zinc-aluminum alloy powder is used to consume corrosive media through a sacrificial anode mechanism, resisting salt spray corrosion. The specific technical solution is as follows:

[0007] A wear-resistant industrial coating comprises the following raw materials in parts by weight: 45-55 parts modified epoxy resin liquid, 15-20 parts modified phenolic resin liquid, 8-12 parts zirconium boride powder, 10-15 parts silicon carbide powder, 0.5-1 part hexagonal boron nitride powder, 18-22 parts flake zinc-aluminum alloy powder, 6-7 parts methylhexahydrophthalic anhydride, 3-4 parts hexamethoxymethylmelamine, and 0.3 parts accelerator. The modified epoxy resin liquid is obtained by modifying hydrogenated bisphenol A type epoxy resin with hydroxyl-terminated trifluoropropylmethyl polysiloxane; the modified phenolic resin liquid is obtained by mixing linear phenolic resin after etherification with soluble polyimide powder.

[0008] The modified epoxy resin liquid in the above coating is prepared by: mixing hydrogenated bisphenol A type epoxy resin and hydroxyl-terminated trifluoropropyl methyl polysiloxane in a mass ratio of 1:(0.8-1.2), adding propylene glycol methyl ether acetate and tetraisopropyl titanate, stirring, reacting at 90℃-95℃ for 3-4 hours, and cooling to room temperature to obtain the modified epoxy resin liquid.

[0009] In the above-mentioned method for preparing modified epoxy resin liquid, the amount of propylene glycol methyl ether acetate added is 1 to 1.5 times the mass of the mixture; the amount of tetraisopropyl titanate added is 0.2% to 0.3% of the mass of hydroxyl-terminated trifluoropropylmethyl polysiloxane; and the stirring is carried out at 55°C to 60°C for 20 to 30 minutes.

[0010] The preparation method of the modified phenolic resin liquid in the above coating includes: dissolving linear phenolic resin in a mixed solvent; adding benzyl alcohol and p-toluenesulfonic acid, refluxing and etherifying under nitrogen protection, adding soluble polyimide powder and BYK-110 dispersant, refluxing and stirring, cooling, adding BHT antioxidant, stirring and mixing to obtain the modified phenolic resin liquid.

[0011] In the above-mentioned method for preparing modified phenolic resin solution, the amount of the mixed solvent is 1.5 to 2 times the mass of the linear phenolic resin; the temperature of the mixed solvent is 78℃ to 82℃; the mixed solvent is a mixture of N,N-dimethylformamide and isopropanol in a mass ratio of (3 to 5): (1 to 2); the amount of benzyl alcohol added is 15% to 20% of the mass of the linear phenolic resin; the amount of p-toluenesulfonic acid added is 0.5% to 1.0% of the mass of the linear phenolic resin; and the reflux etherification reaction is a reflux etherification reaction at 110℃ to 120℃ for 2 to 2.5 hours.

[0012] In the above-mentioned method for preparing modified phenolic resin liquid, the cooling is to cool to 78℃~82℃; the amount of soluble polyimide powder added is 10%~15% of the mass of linear phenolic resin; the amount of BYK-110 dispersant added is 0.4%~0.6% of the mass of linear phenolic resin; the reflux stirring is to reflux and stir at 110℃~120℃ and 600rpm~800rpm for 1h~2h; the cooling is to cool to room temperature; the amount of BHT antioxidant added is 0.1%~0.2% of the mass of linear phenolic resin; and the stirring and mixing is to stir and mix at 200rpm~300rpm for 5min~10min.

[0013] In the above coatings, the particle size range of the zirconium boride powder, silicon carbide powder, hexagonal boron nitride powder, and flake zinc-aluminum alloy powder is all below 800-900 mesh sieve.

[0014] In the above coating, the accelerator is benzyldimethylamine.

[0015] In the above coating, the catalyst is p-toluenesulfonic acid.

[0016] In the above coating, the dispersant is BYK-2155 wetting and dispersing agent.

[0017] In the above coating, the thixotropic agent is a compound of polyamide wax and fumed silica in a mass ratio of (1-1.2):(1.5-1.8).

[0018] In the above-mentioned coating, the defoamer is BYK-1790 defoamer.

[0019] In the above coating, the mixed solvent is a mixture of N,N-dimethylformamide, xylene and butanol in a mass ratio of (5-6):(3-4):(2-3).

[0020] The above-mentioned method for manufacturing an abrasion-resistant industrial coating includes the following steps:

[0021] According to the mass fractions, the modified epoxy resin liquid and modified phenolic resin liquid are added to the mixed solvent and stirred to obtain the base material; the dispersant, zirconium boride powder and silicon carbide powder are added to the base material in sequence and stirred; then hexagonal boron nitride powder, thixotropic agent and defoamer are added and sheared to activate; under stirring conditions, the catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine and accelerator are added in sequence and stirred; the flake zinc-aluminum alloy powder is added and stirred to obtain the coating.

[0022] In the above-mentioned method for manufacturing coatings, modified epoxy resin liquid and modified phenolic resin liquid are added to a mixed solvent and stirred at 60℃~65℃ and 300rpm~400rpm for 20min~30min to obtain a base material; a dispersant, zirconium boride powder and silicon carbide powder are added to the base material in sequence and stirred at 150rpm~200rpm for 20min~30min; then hexagonal boron nitride powder, thixotropic agent and defoamer are added and sheared at 60℃~65℃ and 600rpm~800rpm for 8min~12min; the temperature is lowered to below 40℃, and under stirring conditions of 200rpm~250rpm, a catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine and accelerator are added in sequence and stirred at 300rpm~400rpm for 10min~20min; finally, flake zinc-aluminum alloy powder is added and stirred at 150rpm~200rpm for 15min~20min to obtain the coating.

[0023] The present invention provides a wear-resistant industrial coating and its manufacturing method, which have the following beneficial effects:

[0024] I. This invention's coating, through multi-component synergistic design and process optimization, exhibits excellent comprehensive performance under extreme conditions such as high temperature and strong erosion. Its core advantages lie in: the composite base material formed by hydrogenated epoxy resin and phenolic resin, combined with silicone-fluorine modification and polyimide reinforcement technology, enables the coating to possess both the strong adhesion of epoxy resin and the high-temperature resistance of phenolic resin, maintaining chemical bonding with the metal substrate even at high temperatures. Wear-resistant fillers (silicon carbide and zirconium boride) construct an anti-wear skeleton, which, combined with the lubricating effect of hexagonal boron nitride, results in low initial wear resistance mass loss and low increase after temperature resistance, forming a "hard skeleton + soft lubrication" wear-resistant system. In terms of corrosion protection, the flake zinc-aluminum alloy powder consumes corrosive media through a sacrificial anode mechanism, resisting salt spray corrosion. Furthermore, the curing agent system (methylhexahydrophthalic anhydride and hexamethoxymethylmelamine) increases the crosslinking density, enabling the coating hardness to reach 6H, and only decreasing to 5H after temperature resistance, demonstrating excellent thermal stability.

[0025] II. In the preparation of modified epoxy resin solution, hydrogenated bisphenol A epoxy resin and hydroxyl-terminated trifluoropropylmethyl polysiloxane are compounded in a specific ratio. The silicon-oxygen bonds (Si-O-Si) impart low surface energy and thermal stability to the resin, while fluorine enhances chemical inertness. Propylene glycol methyl ether acetate dissolves the resin and adjusts the viscosity of the reaction system. Tetraisopropyl titanate catalyzes the reaction between hydroxyl and epoxy groups, forming flexible molecular chains and reducing the risk of hard, brittle, and cracked coatings. As a film-forming substance in coatings, its chemical bonding with the metal substrate ensures adhesion, while silicon-fluorine modification improves temperature resistance and corrosion resistance.

[0026] III. In the preparation of modified phenolic resin liquid, linear phenolic resin undergoes an etherification reaction with benzyl alcohol and p-toluenesulfonic acid under nitrogen protection to form a network structure, improving heat resistance. The addition of soluble polyimide powder (10%–15% of the resin mass) enhances the crosslinking density through its aromatic ring structure. BYK-110 dispersant prevents polyimide agglomeration, and BHT antioxidant inhibits high-temperature oxidation. In coatings, it synergistically works with modified epoxy resin, increasing the hardness to 6H through the rigid segments of polyimide, while the network structure of the etherified phenolic resin enhances temperature resistance, making the coating less prone to softening at high temperatures and maintaining good temperature stability.

[0027] IV. The high-temperature resistance of zirconium boride enables the coating to maintain the stability of the skeleton under high-temperature conditions, while the high hardness of silicon carbide forms an anti-wear skeleton. The combination of the two significantly reduces the mass loss of the coating in the rotating rubber grinding wheel test.

[0028] 5. The flake-shaped zinc-aluminum alloy powder, used as a sacrificial anode material, preferentially oxidizes in a salt spray environment to form a protective film of zinc oxide and aluminum oxide, blocking the penetration of corrosive media. Its flake-like structure increases the pore path length of the coating, forming a dense barrier with the resin matrix.

[0029] VI. Curing Agent System (Methylhexahydrophthalic anhydride, hexamethoxymethylmelamine): Methylhexahydrophthalic anhydride reacts with the epoxy groups of the epoxy resin to form a three-dimensional cross-linked structure, improving hardness and chemical stability; hexamethoxymethylmelamine cross-links with the hydroxyl groups of the phenolic resin, further densifying the network. The two are mixed in a specific ratio to ensure a moderate degree of cross-linking, avoiding brittleness caused by over-cross-linking, and resulting in high hardness retention after temperature resistance.

[0030] 7. BYK-2155 dispersant prevents filler agglomeration through steric hindrance, ensuring uniform distribution of the wear-resistant skeleton; the thixotropic agent, a combination of polyamide wax and fumed silica, gives the coating shear-thinning properties during spraying, preventing sagging; BYK-1790 defoamer eliminates bubbles generated during construction, preventing pinhole defects in the coating.

[0031] 8. In the coating manufacturing process, the modified phenolic resin is refluxed at 110℃~120℃ for 2h~2.5h to form a partially cross-linked structure. Subsequently, it is refluxed and stirred with polyimide powder at the same temperature to promote the molecular fusion of polyimide and etherified phenolic resin.

[0032] 9. In the coating manufacturing process, after cooling to below 40°C, the catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine, and accelerator are added in sequence. On the one hand, this avoids premature reaction of the curing agent at high temperatures; on the other hand, the catalyst and accelerator are added alternately, which effectively reduces the neutralization consumption of the catalyst and accelerator, and inhibits premature cross-linking caused by neutralization exothermic reaction.

[0033] 10. In coating manufacturing, zinc-aluminum alloy powder is added last to prevent the flaky powder from deforming due to high shear force, maintaining its layered distribution and maximizing the sacrificial anodic protection effect. If the stirring intensity is too high, the breakage rate of zinc-aluminum alloy powder will increase, and the penetration path of corrosive media will increase during salt spray testing. Detailed Implementation

[0034] The present invention will be further described below with reference to specific implementation examples, but the present invention is not limited to these embodiments.

[0035] Example 1

[0036] A wear-resistant industrial coating comprises the following raw materials in parts by weight: 45 parts modified epoxy resin liquid, 15 parts modified phenolic resin liquid, 8 parts zirconium boride powder, 10 parts silicon carbide powder, 0.5 parts hexagonal boron nitride powder, 18 parts flake zinc-aluminum alloy powder, 6 parts methylhexahydrophthalic anhydride, 3 parts hexamethoxymethylmelamine, 0.3 parts accelerator, 0.2 parts catalyst, 1.5 parts dispersant, 1.0 part thixotropic agent, 0.3 parts defoamer, and 40 parts mixed solvent. The accelerator is benzyl dimethylamine; the catalyst is p-toluenesulfonic acid; the dispersant is BYK-2155 wetting and dispersing agent; the thixotropic agent is a mixture of polyamide wax and fumed silica in a mass ratio of 1:1.5; the defoamer is BYK-1790 defoamer; and the mixed solvent is a mixture of N,N-dimethylformamide, xylene, and butanol in a mass ratio of 5:3:2. The particle size range of zirconium boride powder, silicon carbide powder, hexagonal boron nitride powder, and flake zinc-aluminum alloy powder all pass through an 800-mesh sieve.

[0037] The preparation method of the modified epoxy resin liquid includes: mixing hydrogenated bisphenol A type epoxy resin and hydroxyl-terminated trifluoropropylmethyl polysiloxane in a mass ratio of 1:0.8, adding propylene glycol methyl ether acetate (1 times the mass of the mixture) and tetraisopropyl titanate (0.2% by mass of hydroxyl-terminated trifluoropropylmethyl polysiloxane), stirring at 55°C and 300 rpm for 20 min, reacting at 90°C and 200 rpm for 3 h, and cooling to room temperature to obtain the modified epoxy resin liquid.

[0038] The preparation method of the modified phenolic resin solution includes: dissolving linear phenolic resin in 1.5 times its mass of a mixed solvent at 78°C, wherein the mixed solvent is N,N-dimethylformamide and isopropanol in a mass ratio of 3:1; then adding 15% benzyl alcohol and 0.5% p-toluenesulfonic acid by mass of linear phenolic resin, and refluxing the reaction at 110°C and 200 rpm for 2 hours under nitrogen protection, maintaining the temperature at 110°C, adding 10% soluble polyimide powder and 0.4% BYK-110 dispersant by mass of linear phenolic resin, refluxing and stirring at 600 rpm for 1 hour, cooling to room temperature, adding 0.1% BHT antioxidant by mass of linear phenolic resin, and stirring and mixing at 200 rpm for 10 minutes to obtain the modified phenolic resin solution.

[0039] The above-mentioned method for manufacturing an abrasion-resistant industrial coating includes the following steps:

[0040] According to the mass fractions, the modified epoxy resin liquid and modified phenolic resin liquid were added to the mixed solvent and stirred at 60℃ and 300rpm for 20min to obtain the base material; the dispersant, zirconium boride powder and silicon carbide powder were added to the base material in sequence and stirred at 150rpm for 20min; then hexagonal boron nitride powder, thixotropic agent and defoamer were added and sheared at 60℃ and 600rpm for 8min; the temperature was lowered to below 40℃, and under stirring at 200rpm, the catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine and accelerator were added in sequence and stirred at 300rpm for 10min; flake zinc-aluminum alloy powder was added and stirred at 150rpm for 5min to obtain the coating.

[0041] Example 2

[0042] A wear-resistant industrial coating comprises the following raw materials in parts by weight: 50 parts modified epoxy resin liquid, 18 parts modified phenolic resin liquid, 10 parts zirconium boride powder, 13 parts silicon carbide powder, 0.8 parts hexagonal boron nitride powder, 20 parts flake zinc-aluminum alloy powder, 6.5 parts methylhexahydrophthalic anhydride, 3.5 parts hexamethoxymethylmelamine, 0.4 parts accelerator, 0.3 parts catalyst, 1.7 parts dispersant, 1.3 parts thixotropic agent, 0.4 parts defoamer, and 42 parts mixed solvent. The accelerator is benzyl dimethylamine; the catalyst is p-toluenesulfonic acid; the dispersant is BYK-2155 wetting and dispersing agent; the thixotropic agent is a mixture of polyamide wax and fumed silica at a mass ratio of 1.1:1.7; the defoamer is BYK-1790 defoamer; and the mixed solvent is a mixture of N,N-dimethylformamide, xylene, and butanol at a mass ratio of 5.5:3.5:2.5. The particle size range of zirconium boride powder, silicon carbide powder, hexagonal boron nitride powder, and flake zinc-aluminum alloy powder all passes through an 800-mesh sieve.

[0043] The preparation method of the modified epoxy resin liquid includes: mixing hydrogenated bisphenol A type epoxy resin and hydroxyl-terminated trifluoropropylmethyl polysiloxane in a mass ratio of 1:1, adding propylene glycol methyl ether acetate (1.2 times the mass of the mixture) and tetraisopropyl titanate (0.25% by mass of hydroxyl-terminated trifluoropropylmethyl polysiloxane), stirring at 58°C and 350 rpm for 25 min, reacting at 92°C and 250 rpm for 3.5 h, and cooling to room temperature to obtain the modified epoxy resin liquid.

[0044] The preparation method of the modified phenolic resin solution includes: dissolving linear phenolic resin in 1.8 times its mass of a mixed solvent at 80℃, wherein the mixed solvent is N,N-dimethylformamide and isopropanol in a mass ratio of 4:1.5; then adding 18% benzyl alcohol and 0.8% p-toluenesulfonic acid by mass of linear phenolic resin, and refluxing the mixture at 115℃ and 250 rpm for 2 hours under nitrogen protection, maintaining the temperature at 115℃, adding 12% soluble polyimide powder and 0.5% BYK-110 dispersant by mass of linear phenolic resin, refluxing and stirring at 700 rpm for 1.5 hours, cooling to room temperature, adding 0.15% BHT antioxidant by mass of linear phenolic resin, and stirring and mixing at 250 rpm for 15 minutes to obtain the modified phenolic resin solution.

[0045] The above-mentioned method for manufacturing an abrasion-resistant industrial coating includes the following steps:

[0046] According to the mass fractions, the modified epoxy resin liquid and modified phenolic resin liquid were added to the mixed solvent and stirred at 62℃ and 350rpm for 25min to obtain the base material; dispersant, zirconium boride powder and silicon carbide powder were added to the base material in sequence and stirred at 180rpm for 25min; then hexagonal boron nitride powder, thixotropic agent and defoamer were added and sheared at 62℃ and 700rpm for 10min; the temperature was lowered to below 40℃, and under stirring at 220rpm, catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine and accelerator were added in sequence and stirred at 350rpm for 15min; flake zinc-aluminum alloy powder was added and stirred at 180rpm for 8min to obtain the coating.

[0047] Example 3

[0048] A wear-resistant industrial coating comprises the following raw materials in parts by weight: 55 parts modified epoxy resin liquid, 20 parts modified phenolic resin liquid, 12 parts zirconium boride powder, 15 parts silicon carbide powder, 1 part hexagonal boron nitride powder, 22 parts flake zinc-aluminum alloy powder, 7 parts methylhexahydrophthalic anhydride, 4 parts hexamethoxymethylmelamine, 0.5 parts accelerator, 0.4 parts catalyst, 2 parts dispersant, 1.5 parts thixotropic agent, 0.5 parts defoamer, and 45 parts mixed solvent. The accelerator is benzyl dimethylamine; the catalyst is p-toluenesulfonic acid; the dispersant is BYK-2155 wetting and dispersing agent; the thixotropic agent is a mixture of polyamide wax and fumed silica in a mass ratio of 1.2:1.8; the defoamer is BYK-1790 defoamer; and the mixed solvent is a mixture of N,N-dimethylformamide, xylene, and butanol in a mass ratio of 6:4:3. The particle size range of zirconium boride powder, silicon carbide powder, hexagonal boron nitride powder, and flake zinc-aluminum alloy powder all pass through a 900-mesh sieve.

[0049] The preparation method of the modified epoxy resin liquid includes: mixing hydrogenated bisphenol A type epoxy resin and hydroxyl-terminated trifluoropropylmethyl polysiloxane in a mass ratio of 1:1.2, adding propylene glycol methyl ether acetate (1.5 times the mass of the mixture) and tetraisopropyl titanate (0.3% by mass of hydroxyl-terminated trifluoropropylmethyl polysiloxane), stirring at 60°C and 400 rpm for 30 min, reacting at 95°C and 300 rpm for 4 h, and then cooling to room temperature to obtain the modified epoxy resin liquid.

[0050] The preparation method of the modified phenolic resin solution includes: dissolving linear phenolic resin in a mixed solvent at 82℃ with a mass ratio of N,N-dimethylformamide to isopropanol of 5:2; then adding 20% ​​benzyl alcohol and 1.0% p-toluenesulfonic acid by mass of the linear phenolic resin, and refluxing at 120℃ and 300rpm for etherification reaction under nitrogen protection for 2.5h. Maintaining 120℃, adding 15% soluble polyimide powder and 0.6% BYK-110 dispersant by mass of the linear phenolic resin, and refluxing at 800rpm for 2h. Cooling to room temperature, adding 0.2% BHT antioxidant by mass of the linear phenolic resin, and stirring at 300rpm for 20min to obtain the modified phenolic resin solution.

[0051] The above-mentioned method for manufacturing an abrasion-resistant industrial coating includes the following steps:

[0052] According to the mass fractions, the modified epoxy resin liquid and modified phenolic resin liquid were added to the mixed solvent and stirred at 65℃ and 400rpm for 30min to obtain the base material; the dispersant, zirconium boride powder and silicon carbide powder were added to the base material in sequence and stirred at 200rpm for 30min; then hexagonal boron nitride powder, thixotropic agent and defoamer were added and sheared at 65℃ and 800rpm for 12min; the temperature was lowered to below 40℃, and under stirring at 250rpm, the catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine and accelerator were added in sequence and stirred at 400rpm for 20min; flake zinc-aluminum alloy powder was added and stirred at 200rpm for 10min to obtain the coating.

[0053] The specifications and sources of the coating raw materials in the above embodiments are as follows: Hydrogenated bisphenol A type epoxy resin is from Wuhan Jiufengyun New Material Co., Ltd., model XY518. Hydroxyl-terminated trifluoropropylmethyl polysiloxane is from Shanghai Hansi Chemical Co., Ltd. Propylene glycol methyl ether acetate is from Tianmingyuan Chemical (Shanghai) Co., Ltd. Tetraisopropyl titanate is from Yizheng Tianyang Chemical Co., Ltd. Linear phenolic resin is from Jinan Dahui Chemical Technology Co., Ltd. N,N-dimethylformamide is from Nantong Runfeng Petrochemical Co., Ltd. Isopropanol is from Liaocheng Tongda Chemical Co., Ltd. Benzyl alcohol is from Wuhan Xuzeng Boyuan Chemical Co., Ltd. p-Toluenesulfonic acid is from Changzhou Junchi Chemical Co., Ltd. Soluble polyimide powder is from Suzhou Taolian Plastics Co., Ltd., model KF-1. Zirconium boride powder is from Shanghai Xiangtian Nanomaterials Co., Ltd. Silicon carbide powder is from Shanghai Shuitian Materials Technology Co., Ltd. Hexagonal boron nitride powder is from Qinghe County Zhongzhou Alloy Materials Co., Ltd. Flake zinc-aluminum alloy powder is from Hebei Xingke Powder Materials Technology Co., Ltd. Methylhexahydrophthalic anhydride was sourced from Nantong Runfeng Petrochemical Co., Ltd. Hexamethoxymethyl melamine was sourced from Jiangsu Puleisi Biotechnology Co., Ltd. Benzyl dimethylamine was sourced from Shanghai Deyin Chemical Co., Ltd. The polyamide wax was Disparlon 6900-20X anti-settling agent. The fumed silica was Aerosil R812 hydrophobic fumed silica.

[0054] Comparative Example 1

[0055] The difference from Example 1 is that the modified epoxy resin liquid is changed to 15 parts and the modified phenolic resin liquid is changed to 45 parts.

[0056] Comparative Example 2

[0057] The difference from Example 1 is that methylhexahydrophthalic anhydride is changed to 3 parts and hexamethoxymethylmelamine is changed to 6 parts.

[0058] Comparative Example 3

[0059] The difference from Example 1 is that the modified epoxy resin liquid is changed to 15 parts, the modified phenolic resin liquid is changed to 45 parts, and the methyl hexahydrophthalic anhydride is changed to 3 parts, and the hexamethoxymethyl melamine is changed to 6 parts.

[0060] Comparative Example 4

[0061] The difference from Example 1 is that the modified epoxy resin liquid is prepared without the addition of hydroxyl-terminated trifluoropropylmethylpolysiloxane.

[0062] Comparative Example 5

[0063] The difference from Example 1 is that in the preparation method of the modified epoxy resin liquid, the mass ratio of hydrogenated bisphenol A type epoxy resin to hydroxyl-terminated trifluoropropylmethyl polysiloxane is changed to 1:2.

[0064] Comparative Example 6

[0065] The difference from Example 1 is that in the preparation method of the modified phenolic resin liquid, the amount of soluble polyimide powder added is changed to 5% of the mass of linear phenolic resin.

[0066] Comparative Example 7

[0067] The difference from Example 1 is that in the preparation method of the modified phenolic resin liquid, the amount of soluble polyimide powder added is changed to 25% of the mass of linear phenolic resin.

[0068] Comparative Example 8

[0069] The difference from Example 1 is that BYK-110 dispersant is not added in the preparation method of the modified phenolic resin liquid.

[0070] Comparative Example 9

[0071] The difference from Example 1 is that in the preparation method of the modified phenolic resin liquid, the reflux stirring temperature is changed to 60°C (which cannot reach the reflux temperature).

[0072] Comparative Example 10:

[0073] Soluble polyimide powder was replaced with a liquid solution containing 20 wt% polyimide powder in an N,N-dimethylformamide solution. The amount of soluble polyimide powder added was 50% of the mass of linear phenolic resin. No reflux stirring was performed, and the mixture was stirred at room temperature for 1 hour.

[0074] Comparative Example 11

[0075] The difference from Example 1 is that: in the preparation method of the modified phenolic resin liquid, benzyl alcohol and p-toluenesulfonic acid are not added, and the reflux etherification reaction is not carried out; it is directly refluxed and stirred with soluble polyimide powder and BYK-110 dispersant.

[0076] Comparative Example 12

[0077] The difference from Example 1 is that in the method of manufacturing the coating, the order of adding the catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine and accelerator is modified to: adding the catalyst, accelerator, methylhexahydrophthalic anhydride and hexamethoxymethylmelamine in sequence.

[0078] I. Sample Preparation:

[0079] Substrate selection: Q235 steel plate with dimensions of 100mm×100mm×2mm and a surface roughness of Ra3.2-4.0μm was selected and cleaned with acetone to remove oil and impurities. Coating: The coating thickness was controlled at 150±5μm, cured at 80℃ for 30min, then heated to 120℃ for 1h, and then heated to 170℃ for 2.5h to obtain the sample.

[0080] II. Testing Items:

[0081] 1. Adhesion: According to GB / T 9286 "Cross-cut test for paint and varnish films", a 1mm × 1mm grid is drawn on the coating surface using a cross-cutting tool, with the grid depth reaching the substrate. Then, 3M tape (600 grade) is applied to the grid area and quickly peeled off at a 90° angle. The extent of grid peeling is observed. Rating: Grade 0: Peeling area ≤ 5%, cut edges are completely smooth, no grid peeling; Grade 1: Peeling area > 5% and ≤ 15%, a small amount of coating peeling at the intersection of cuts, but no peeling at the grid edges. Level 1: Peeling; Level 2: Peeling area > 15% and ≤ 35%, with localized peeling at cut intersections and grid edges, peeling area ≤ 35%; Level 3: Peeling area > 35% and ≤ 65%, with large areas of coating peeling off along cut edges or intersections, peeling area > 35% and ≤ 65%; Level 4: Peeling area > 65% and ≤ 85%, with large areas of coating peeling off, peeling area > 65% and ≤ 85%; Level 5: Peeling area > 85%, with almost all coating peeling off;

[0082] 2. Hardness: According to GB / T 6739 "Determination of Hardness of Paints and Varnishes by Pencil Method", use a hardness pencil (from H to 6H) to scratch the coating surface at a 45° angle and a pressure of 1 kg at a uniform speed. Find the hardest pencil hardness grade that does not scratch the coating and record the corresponding hardness value.

[0083] 3. Abrasion resistance: Refer to GB / T 1768 "Determination of abrasion resistance of paints and varnishes - Rotary rubber grinding wheel method", use an abrasion testing machine, select CS-10 rubber grinding wheel, 500g load, 1000 revolutions; record the mass loss (unit: mg).

[0084] 4. Corrosion Resistance: According to GB / T 1771 "Determination of Resistance to Neutral Salt Spray of Paints and Varnishes", the sample is placed in a salt spray test chamber with a salt solution concentration of 5 wt% and a temperature of 35℃. After continuous spraying for 2500 hours, the corrosion of the coating surface is observed and evaluated as follows: Grade 0: No blistering or peeling, blistering area 0%; Grade 1: Slight blistering, no peeling, blistering area > 0% and ≤ 5%; Grade 2: Small blistering area, no peeling, blistering area > 5% and ≤ 15%; Grade 3: Large blistering area, localized slight peeling, blistering area > 15% and ≤ 30%, and / or peeling area < 10%; Grade 4: Very large blistering area, large peeling area, blistering area > 30% and ≤ 50%, and / or peeling area > 10% and ≤ 30%; Grade 5: Very severe blistering and peeling, blistering area > 50%, and / or peeling area > 30%.

[0085] 5. Temperature resistance: Place the sample in a high-temperature chamber and heat it to 120°C at a rate of 5°C / min. After holding it at that temperature for 48 hours, cool it to room temperature and test the adhesion, hardness, and abrasion resistance according to the above method.

[0086] Table 1. Test results (values ​​for 3 parallel samples)

[0087]

[0088] The results above show that in Examples 1 to 3, the modified epoxy resin, by introducing hydroxyl-terminated trifluoropropyl polysiloxane, enhances heat resistance and chemical inertness through silicon and fluorine, resulting in stable molecular chains, good toughness and adhesion, and resistance to hardening, cracking, and peeling. The modified phenolic resin, by introducing soluble polyimide powder, enhances the crosslinking density and temperature resistance of the coating. This gives the coating high hardness, high wear resistance, and good temperature stability. Zirconium boride powder (high temperature resistance), silicon carbide powder (wear-resistant skeleton), and flake zinc-aluminum alloy powder (sacrificial anode corrosion protection) are used in combination with the composite resin to form a denser wear-resistant and corrosion-resistant structure. The curing agent, a combination of methylhexahydrophthalic anhydride and hexamethoxymethylmelamine, improves the degree of crosslinking, effectively enhancing the coating's hardness and temperature stability. The combination of these components effectively protects the substrate.

[0089] In Comparative Example 1, the reduction of modified epoxy resin liquid (15 parts) and the increase of modified phenolic resin liquid (45 parts) disrupted the synergistic effect of the resin system. The chemical bonding force between the epoxy groups of epoxy resin and the metal substrate weakened, resulting in decreased adhesion. Although phenolic resin is heat resistant, it has poor flexibility. Excessive use will make the coating brittle. Although the hardness will temporarily increase due to the increased brittleness, the coating will become brittle, and its ability to resist external scratches under stress will decrease. Due to insufficient adhesion of the resin base material, the ceramic fillers (silicon carbide, zirconium boride) in the wear-resistant skeleton structure are prone to falling off, resulting in increased mass loss.

[0090] In Comparative Example 2, the amount of methylhexahydrophthalic anhydride (an acid anhydride curing agent) was reduced (3 parts), while the amount of hexamethoxymethylmelamine (an amino resin crosslinking agent) was increased (6 parts), resulting in insufficient curing reaction. The reduced crosslinking density between the acid anhydride curing agent and the epoxy resin led to a looser coating network structure, resulting in decreased hardness. Insufficient crosslinking increased internal stress in the coating, making it prone to peeling during cross-cut testing. Wear resistance was affected by the stability of the skeleton structure; the loose structure made the filler more susceptible to wear. Corrosion resistance decreased due to insufficient coating density, leading to accelerated salt spray penetration. Hexamethoxymethylmelamine is particularly effective for crosslinking phenolic resins; excessive amounts can cause localized over-crosslinking, leading to internal stress and affecting performance.

[0091] In Comparative Example 3, the imbalance of resin ratio and improper curing agent ratio had a dual effect. Insufficient epoxy resin content led to loss of adhesion to the substrate, while excessive phenolic resin caused coating embrittlement. Insufficient methylhexahydrophthalic anhydride curing agent further exacerbated inadequate crosslinking, resulting in a loose coating structure that was prone to cracking. Wear-resistant fillers, lacking sufficient resin bonding, detached in large quantities during friction; the protective effect of the zinc-aluminum alloy powder failed due to the damage to coating integrity; insufficient crosslinking density resulted in poor resistance to salt spray corrosion; and the embrittled coating was more prone to peeling under thermal stress.

[0092] In Comparative Example 4, the absence of hydroxyl-terminated trifluoropropylmethyl polysiloxane caused the modified epoxy resin to lose the high-temperature resistance and low surface energy properties of the siloxane bond (Si-O-Si). The introduction of the siloxane improves the interfacial compatibility between the resin and the metal substrate; its absence reduces adhesion. The flexibility of the siloxane bond balances the brittleness of the epoxy resin, and consequently balances the hardness and brittleness of the phenolic resin, resulting in a coating with good performance. Although the hardness of the modified coating increases due to the increased rigidity of the resin itself, the adhesion decreases, making it prone to brittle cracking and peeling under stress. Corrosion resistance decreases due to insufficient surface density of the coating; the lack of hydrophobic properties of the siloxane leads to accelerated salt spray penetration. In the temperature resistance test, the resin exhibits insufficient thermal stability, and its performance deteriorates after high temperatures.

[0093] In Comparative Example 5, the excessive amount of hydroxyl-terminated trifluoropropylmethyl polysiloxane (1:2) led to over-diluting of the epoxy groups in the epoxy resin, weakening its chemical bonding with the substrate. The excessive flexible segments of the siloxane reduced the cross-linking density of the resin system, decreased the coating hardness, and made the coating prone to peeling off during cross-cutting due to excessive flexibility. The wear-resistant filler was prone to displacement in the flexible matrix, exacerbating wear during friction. The excessive introduction of siloxane caused microphase separation within the coating, resulting in uneven temperature resistance and decreased performance.

[0094] In Comparative Example 6, the amount of soluble polyimide powder added was insufficient (5%), failing to fully utilize its high-temperature resistance and rigidity enhancement effects. The aromatic ring structure of polyimide improves the thermal stability of phenolic resin; however, insufficient addition resulted in decreased coating adhesion after the temperature resistance test. Insufficient rigid segments reduced coating hardness and weakened its resistance to friction. Insufficient optimization of the crosslinking network of phenolic resin by polyimide resulted in slightly poorer coating density and susceptibility to salt spray corrosion; however, because the basic formulation still contained zinc-aluminum alloy powder, the degree of corrosion was relatively mild.

[0095] In Comparative Example 7, the excess polyimide powder (25%) made dispersion in the phenolic resin difficult, leading to agglomeration and defects. Excess rigid segments significantly increased the coating's brittleness; coupled with uneven mass and increased stress, the actual scratch resistance was lower than in Example 1. Agglomerates caused stress concentration within the coating, and combined with thermal stress, the coating easily detached along defects during cross-cut testing after heat resistance, making the brittle coating more prone to cracking under thermal stress. In the abrasion test, the weak bonding between the filler and resin interface at agglomerated areas resulted in micropores and accelerated wear.

[0096] In Comparative Example 8, the absence of BYK-110 dispersant resulted in uneven dispersion of soluble polyimide powder in the phenolic resin, leading to localized agglomerations. Poor dispersion resulted in an uneven internal structure of the coating. Under thermal stress, the agglomerated areas were prone to detachment during cross-cutting. Hardness decreased due to the rigidity differences in the agglomerated areas. Abrasion resistance was affected by the filler dispersion state; the filler at the agglomerated areas was not tightly bonded to the resin, creating micropores that were easily detached during friction. In salt spray corrosion, the uneven microporous structure reduced the protective performance of the coating.

[0097] In Comparative Example 9, the reflux stirring temperature (60℃) further prolongs the etherification reaction and promotes the solubility of the soluble polyimide powder and its integration with the etherified phenolic resin. If the required temperature (normally above 110℃) is not reached, the etherification reaction is incomplete, and the integration of the soluble polyimide powder with the etherified phenolic resin is poor. The resin molecular chains cannot be fully cross-linked, resulting in insufficient binder strength; the unreacted phenolic resin has few active groups, leading to poor compatibility with the polyimide powder and a loose coating structure; the hardness decreases significantly due to insufficient cross-linking density; the wear-resistant filler detaches in large quantities due to weak binder strength; in salt spray corrosion, the loose structure cannot effectively block the medium; and the insufficiently cured coating further decomposes at high temperatures, resulting in performance deterioration.

[0098] In Comparative Example 10, a polyimide solution was used instead of powder, and the mixture was stirred at room temperature. The introduction of N,N-dimethylformamide solvent, a high-boiling-point solvent, affected the molding properties. Furthermore, stirring at room temperature resulted in poor compatibility between the polyimide and the etherified phenolic resin, and shortened the etherification time of the phenolic resin, leading to incomplete reaction and a decline in various properties.

[0099] In Comparative Example 11, the linear phenolic resin skipped the etherification reaction and was directly mixed with polyimide powder and dispersant. The resin molecular chain remained linear and did not form a network crosslink. The linear phenolic resin had extremely poor adhesion and heat resistance, resulting in poor adhesion between the coating and the substrate. Although the coating grade was within the same range as Comparative Example 9, the peeling rate was higher than that of Comparative Example 9. The crosslinked coating had low hardness and significantly reduced wear resistance. Due to the lack of a dense resin matrix protection, the zinc-aluminum alloy powder coating had poor salt spray corrosion resistance. The linear resin underwent severe thermal decomposition, resulting in poor coating stability.

[0100] In Comparative Example 12, the acidic catalyst and the alkaline accelerator were added sequentially with a short time interval. Some of the acidic catalyst and the alkaline accelerator came into direct contact, triggering a partial neutralization reaction. In addition, the alkaline accelerator was added in advance in conjunction with the acidic catalyst. The neutralization reaction was exothermic, and the high temperature caused uneven pre-crosslinking of the resin, forming uneven stress concentration points. Neutralization consumed some of the acidic catalyst and alkaline accelerator, affecting the subsequent crosslinking and causing the coating's various properties to deteriorate.

Claims

1. A wear-resistant industrial coating, characterized in that, The coating comprises the following raw materials in parts by weight: 45-55 parts modified epoxy resin liquid, 15-20 parts modified phenolic resin liquid, 8-12 parts zirconium boride powder, 10-15 parts silicon carbide powder, 0.5-1 part hexagonal boron nitride powder, 18-22 parts flake zinc-aluminum alloy powder, 6-7 parts methylhexahydrophthalic anhydride, 3-4 parts hexamethoxymethylmelamine, 0.3-0.5 parts accelerator, 0.2-0.4 parts catalyst, 1.5-2 parts dispersant, 1.0-1.5 parts thixotropic agent, 0.3-0.5 parts defoamer, and 40-45 parts mixed solvent I; The preparation method of the modified epoxy resin liquid includes: mixing a compound solution according to the mass ratio of hydrogenated bisphenol A type epoxy resin: hydroxyl-terminated trifluoropropyl methyl polysiloxane = 1: (0.8~1.2), adding propylene glycol methyl ether acetate at 1 to 1.5 times the mass of the mixture and tetraisopropyl titanate at 0.2% to 0.3% of the mass of hydroxyl-terminated trifluoropropyl methyl polysiloxane, stirring, reacting at 90℃ to 95℃ for 3h to 4h, and cooling to room temperature to obtain the modified epoxy resin liquid; The method for preparing the modified phenolic resin solution includes: dissolving linear phenolic resin in a mixed solvent II at 78℃~82℃, adding 15%~20% benzyl alcohol and 0.5%~1.0% p-toluenesulfonic acid by weight of the linear phenolic resin, refluxing and etherifying the solution at 110℃~120℃ for 2h~2.5h under nitrogen protection, adding 10%~15% soluble polyimide powder and 0.4%~0.6% BYK-110 dispersant by weight of the linear phenolic resin, refluxing and stirring at 110℃~120℃ and 600rpm~800rpm for 1h~2h, cooling to room temperature, adding 0.1%~0.2% BHT antioxidant by weight of the linear phenolic resin, and stirring to obtain the modified phenolic resin solution; The amount of mixed solvent II is 1.5 to 2 times the mass of linear phenolic resin; the mixed solvent II is a mixed solvent of N,N-dimethylformamide and isopropanol in a mass ratio of (3 to 5): (1 to 2).

2. The wear-resistant industrial coating according to claim 1, characterized in that, In the preparation method of modified epoxy resin liquid, the stirring is carried out at 55℃~60℃ for 20min~30min.

3. The wear-resistant industrial coating according to claim 1, characterized in that, The particle size range of the zirconium boride powder, silicon carbide powder, hexagonal boron nitride powder, and flake zinc-aluminum alloy powder is all within the range of 800-900 mesh sieve.

4. The wear-resistant industrial coating according to claim 1, characterized in that, The accelerator is benzyl dimethylamine; the catalyst is p-toluenesulfonic acid; the dispersant is BYK-2155 wetting and dispersing agent; the thixotropic agent is a mixture of polyamide wax and fumed silica in a mass ratio of (1-1.2):(1.5-1.8); the defoamer is BYK-1790 defoamer; the mixed solvent I is a mixture of N,N-dimethylformamide, xylene, and butanol in a mass ratio of (5-6):(3-4):(2-3).

5. The method for manufacturing an abrasion-resistant industrial coating as described in claim 1, characterized in that, Includes the following steps: According to the mass fractions, the modified epoxy resin liquid and modified phenolic resin liquid are added to mixed solvent I and stirred to obtain the base material; dispersant, zirconium boride powder and silicon carbide powder are added to the base material in sequence and stirred; then hexagonal boron nitride powder, thixotropic agent and defoamer are added and sheared to activate; under stirring conditions, catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine and accelerator are added in sequence and stirred; flake zinc-aluminum alloy powder is added and stirred to obtain the coating.

6. The method for manufacturing an abrasion-resistant industrial coating according to claim 5, characterized in that, Modified epoxy resin liquid and modified phenolic resin liquid were added to mixed solvent I and stirred at 60℃~65℃ and 300rpm~400rpm for 20min~30min to obtain a base material. Dispersant, zirconium boride powder and silicon carbide powder were added to the base material in sequence and stirred at 150rpm~200rpm for 20min~30min. Then hexagonal boron nitride powder, thixotropic agent and defoamer were added and sheared at 60℃~65℃ and 600rpm~800rpm for 8min~12min. The temperature was lowered to below 40℃, and catalyst, methylhexahydrophthalic anhydride, hexamethoxymethylmelamine and accelerator were added in sequence under stirring at 200rpm~250rpm and stirred at 300rpm~400rpm for 10min~20min. Flake zinc-aluminum alloy powder was added and stirred at 150rpm~200rpm for 5min~10min to obtain a coating.

Images