Polymer-based paint and application thereof as well as polymer-based coating and application thereof

Abstract

The invention belongs to the technical field of lubricating materials, and particularly relates to a polymer-based paint and application thereof, and a polymer-based coating and application thereof. The polymer-based coating provided by the invention comprises a component A and a component B, the raw materials for preparing the component A comprise 80-100 parts of resin and more than 0 and less than or equal to 5 parts of ammonia-terminated polydimethylsiloxane, and the resin comprises epoxy resin and / or phenolic resin; the component B comprises more than 0.1 and less than or equal to 2 parts of modified graphene oxide, 0-80 parts of a curing agent, 70-150 parts of a first organic solvent and 2.1-3.2 parts of an auxiliary agent; the modified graphene oxide is graphene oxide of which the surface is grafted with a silane coupling agent. According to the invention, ammonia-terminated polydimethylsiloxane and modified graphene oxide are introduced into the coating; under the combined action of all the materials, the friction coefficient of the coating can be reduced, and the corrosion resistance of the coating is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of lubricating materials, and in particular relates to a polymer-based paint and application thereof, a polymer-based coating and application thereof. Background Art

[0002] Traditional motion mechanisms typically rely on various lubricating oils or greases as lubricants during their service life. Lubricants, with their excellent lubricating properties, ensure the normal operation of the motion mechanism. However, during use, lubricants are inevitably contaminated by various pollutants such as dust, moisture, and impurities, which in turn leads to a decrease in lubrication performance, affecting the working efficiency and service life of the motion mechanism. To overcome this problem, researchers have tried to spray polymer lubricating coatings on the metal dual surfaces to replace traditional lubricants. When the polymer lubricating coating is applied to the metal surface, a strong lubricating film can be formed during the friction process, significantly improving the tribological properties of the coating.

[0003] Polymer resins such as epoxy resins and phenolic resins are widely used as the resin matrix for polymer lubricating coatings due to their excellent adhesion, good mechanical properties, and exceptional chemical stability. However, traditional polymer resin coatings also face challenges during service. For example, due to frequent exposure to humid environments, the coatings are susceptible to erosion by moisture and corrosive media, leading to wear and corrosion. Wear and corrosion, in turn, reinforce each other, forming a vicious cycle that severely reduces the coating's service life. Therefore, the development of polymer resin-based solid lubricating coatings that combine excellent lubrication properties with corrosion resistance is particularly important. Summary of the Invention

[0004] In view of this, the present invention provides a polymer-based coating and its application, a polymer-based coating and its application. The polymer-based coating formed by the polymer-based coating provided by the present invention has both good lubrication properties and corrosion resistance. Applying it to a transmission mechanism will extend its service life and improve its working efficiency.

[0005] In order to solve the above technical problems, the present invention provides a polymer-based coating, comprising component A and component B;

[0006] The raw materials for preparing the component A include 80 to 100 parts of resin and greater than 0 and less than or equal to 5 parts of amino-terminated polydimethylsiloxane, wherein the resin includes epoxy resin and / or phenolic resin;

[0007] The component B includes greater than 0.1 and less than or equal to 2 parts of modified graphene oxide, 0 to 80 parts of a curing agent, 70 to 150 parts of a first organic solvent and 2.1 to 3.2 parts of an auxiliary agent; the modified graphene oxide is graphene oxide with a silane coupling agent grafted on the surface.

[0008] Preferably, the epoxy resin includes one or more of glycidyl ether epoxy resin, glycidyl amine epoxy resin, glycidyl ester epoxy resin and alicyclic epoxy resin;

[0009] The phenolic resin includes thermoplastic phenolic resin and / or thermosetting phenolic resin; when the resin is thermosetting phenolic resin, the component B does not contain a curing agent;

[0010] The number average molecular weight of the aminopolydimethylsiloxane is 500 to 10000 g / mol.

[0011] Preferably, the preparation method of component A comprises the following steps:

[0012] Mixing the resin and aminopolydimethylsiloxane to carry out polymerization reaction to obtain the component A;

[0013] The polymerization reaction temperature is 20-100° C., and the time is 10-300 minutes.

[0014] Preferably, the preparation method of the modified graphene oxide comprises the following steps:

[0015] dispersing graphene oxide in a second organic solvent to obtain a graphene oxide dispersion;

[0016] The graphene oxide dispersion and the silane coupling agent are mixed to carry out a grafting reaction to obtain the modified graphene oxide.

[0017] Preferably, the second organic solvent includes one or more of lower alcohols, benzene solvents, ether solvents, ester solvents and ketone solvents;

[0018] The solid content of the graphene oxide dispersion is 0.01 to 1%;

[0019] The mass ratio of the graphene oxide to the silane coupling agent is 1-3:3-9;

[0020] The grafting reaction is carried out at a temperature of 20 to 200° C. and for a time of 1 to 6 hours.

[0021] Preferably, the curing agent includes one or more of an amine curing agent, an acid anhydride curing agent and a phenolic resin curing agent;

[0022] The first organic solvent includes one or more of lower alcohols, benzene solvents, ether solvents, ester solvents and ketone solvents;

[0023] The auxiliary agent includes one or more of a defoaming agent, a dispersant and a leveling agent.

[0024] The present invention also provides a polymer-based lubricating coating, wherein the preparation method of the polymer-based lubricating coating comprises the following steps:

[0025] The polymer-based lubricating coating is obtained by coating the polymer-based coating described in the above technical solution on the surface of the substrate and then curing the coating.

[0026] Preferably, the curing temperature is 40-200° C., and the holding time is 2-5 hours.

[0027] Preferably, the thickness of the polymer-based lubricating coating is 5 to 50 μm.

[0028] The present invention also provides the use of the polymer-based coating described in the above technical solution or the polymer-based lubricating coating described in the above technical solution in wear-resistant components.

[0029] The present invention provides a polymer-based coating, comprising component A and component B; the raw materials for preparing component A include 80 to 100 parts of resin and greater than 0 and less than or equal to 5 parts of amino-terminated polydimethylsiloxane, the resin including epoxy resin and / or phenolic resin; the component B includes greater than 0.1 and less than or equal to 2 parts of modified graphene oxide, 0 to 80 parts of curing agent, 70 to 150 parts of a first organic solvent and 2.1 to 3.2 parts of an auxiliary agent; the modified graphene oxide is graphene oxide with a silane coupling agent grafted on the surface. The present invention reduces the surface energy of the coating by introducing amino-terminated polydimethylsiloxane (PDMS) into the coating, thereby increasing the water contact angle of the coating, reducing adhesive wear during friction, and reducing the friction coefficient. At the same time, the modified graphene oxide (KGO) in the coating will be evenly dispersed within the coating. The KGO dispersed within the coating and the PDMS on the surface can have a good shielding effect on the corrosive medium, hindering the erosion of the corrosive medium, thereby improving the corrosion resistance of the coating. Applying a polymer-based coating to the surface of a moving part on a substrate (e.g., metal) can reduce friction and improve corrosion resistance, thereby increasing the service life and efficiency of the moving part. In this invention, the epoxy groups (provided by the epoxy resin) and hydroxyl groups in the resin react with the amino groups in polydimethylsiloxane and the amino and hydroxyl groups on the surface of modified graphene oxide, significantly improving the strength of the surface PDMS and the compatibility of the modified graphene oxide with the resin, resulting in a polymer coating with excellent lubricity and corrosion resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The results of scanning electron microscopy on the surface of the polymer-based coating prepared in Example 1 are as follows;

[0031] Figure 2 This is the scanning electron microscopy result of the longitudinal section of the polymer-based coating prepared in Example 1. DETAILED DESCRIPTION

[0032] The present invention provides a polymer-based coating, comprising component A and component B.

[0033] In the present invention, the raw materials for preparing the component A include 80 to 100 parts of resin, which can be 90 to 98 parts, and can be specifically 80 parts, 85 parts, 90 parts, 95 parts, 98 parts or 100 parts; the resin includes epoxy resin and / or phenolic resin, which can be specifically epoxy resin or phenolic resin. As a specific embodiment of the present invention, the epoxy resin (EP) may include one or more of glycidyl ether epoxy resin, glycidyl amine epoxy resin, glycidyl ester epoxy resin and alicyclic epoxy resin, and may specifically be glycidyl ether epoxy resin, glycidyl amine epoxy resin, glycidyl ester epoxy resin or alicyclic epoxy resin; the glycidyl ether epoxy resin may include E-51 epoxy resin or E-44 epoxy resin; the glycidyl amine epoxy resin may include tetraglycidyl diaminodiphenylmethane or triglycidyl p-aminophenol; the glycidyl ester epoxy resin may include diglycidyl phthalate or diglycidyl tetrahydrophthalate; the alicyclic epoxy resin may include hydrogenated bisphenol A epoxy resin or dicyclopentadiene dioxide.

[0034] As a specific embodiment of the present invention, the phenolic resin (PF) may include a thermoplastic phenolic resin and / or a thermosetting phenolic resin, and may specifically be a mixture of a thermoplastic phenolic resin and a thermosetting phenolic resin, a thermosetting phenolic resin or a thermoplastic phenolic resin; the thermoplastic phenolic resin may include a 2123 phenolic resin; the thermosetting phenolic resin may include a 2124 phenolic resin or a 2130 phenolic resin.

[0035] In the present invention, when the resin is a thermosetting phenolic resin, the component B does not contain a curing agent.

[0036] In the present invention, based on the mass fraction of the resin, the component A further comprises greater than 0 and less than or equal to 5 parts of amino-terminated polydimethylsiloxane, which may be 2 to 4 parts, and may specifically be 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts or 5 parts. As a specific embodiment of the present invention, the number average molecular weight of the amino-terminated polydimethylsiloxane may be 500 to 10,000 g / mol, or may be 1,000 to 8,000 g / mol. The present invention limits the number average molecular weight of the amino-terminated polydimethylsiloxane to the above range, and can obtain an amino-terminated polydimethylsiloxane microphase of a suitable size in component A, thereby improving the anti-corrosion and lubrication properties.

[0037] In the present invention, the structural formula of the aminopolydimethylsiloxane is

[0038]

[0039] In the present invention, the amino-terminated polydimethylsiloxane has a low surface energy. Introducing amino-terminated polydimethylsiloxane into the coating will reduce the surface energy of the coating. The reduction in surface energy can prevent the infiltration of corrosive liquid and reduce the shear force and adhesion between the coating and the dual material. By adding a wear-resistant and anti-corrosion filler (modified graphene oxide), the wear resistance and corrosion resistance of the coating are improved under the combined action of the two.

[0040] As a specific embodiment of the present invention, the preparation method of the component A may include the following steps: mixing the resin and amino-terminated polydimethylsiloxane to carry out polymerization reaction to obtain the component A.

[0041] The present invention has no particular limitation on the mixing, as long as the mixing is uniform. As a specific embodiment of the present invention, the temperature of the polymerization reaction can be 20 to 100°C, specifically 20°C, 40°C, 60°C, 80°C or 100°C; the time of the polymerization reaction can be 10 to 300 minutes, specifically 10 minutes, 30 minutes, 50 minutes, 80 minutes, 100 minutes, 150 minutes, 200 minutes, 250 minutes or 300 minutes. As a specific embodiment of the present invention, the polymerization reaction can be accompanied by stirring, and the stirring speed can be below 1000 rpm, and can also be 100 to 800 rpm.

[0042] In the present invention, during the polymerization reaction, the amino group of the aminopolydimethylsiloxane reacts with the hydroxyl group in the resin (the epoxy resin will first open the ring to form hydroxyl groups), and the aminopolydimethylsiloxane is successfully blocked into the resin, significantly improving the hydrophobicity and lubricity of the resin. Taking the resin as an example, the polymerization reaction equation of the epoxy resin and the aminopolydimethylsiloxane is as follows:

[0043]

[0044] In the present invention, component B includes greater than 0.1 and less than or equal to 2 parts of modified graphene oxide, specifically 0.1, 0.5, 1, 1.5, 1.8, or 2 parts, based on the mass fraction of the resin. The modified graphene oxide is graphene oxide with a silane coupling agent grafted onto its surface. As a specific embodiment of the present invention, the method for preparing the modified graphene oxide may include the following steps: dispersing the graphene oxide in a second organic solvent to obtain a graphene oxide dispersion; and mixing the graphene oxide dispersion with a silane coupling agent to undergo a grafting reaction to obtain the modified graphene oxide.

[0045] The present invention disperses graphene oxide (GO) in a second organic solvent to obtain a graphene oxide dispersion. In a specific embodiment of the present invention, the second organic solvent may include one or more of a lower alcohol, a benzene solvent, an ether solvent, an ester solvent, and a ketone solvent. The lower alcohol may include n-butanol and / or ethanol; the benzene solvent may include xylene; the ether solvent may include petroleum ether; the ester solvent may include ethyl acetate and / or butyl acetate; and the ketone solvent may include N-methylpyrrolidone (NMP). The second organic solvent may specifically be n-butanol, ethanol, xylene, petroleum ether, ethyl acetate, butyl acetate, or N-methylpyrrolidone. In a specific embodiment of the present invention, the dispersion may be performed under ultrasonic conditions. The power and duration of the ultrasonication are not particularly limited, as long as uniform dispersion is achieved. In a specific embodiment of the present invention, the solids content of the graphene oxide dispersion may be 0.01-1%, specifically 0.05%, 0.1%, 0.3%, 0.5%, 0.8%, or 1%.

[0046] After obtaining the graphene oxide dispersion, the present invention mixes the graphene oxide dispersion with a silane coupling agent to perform a grafting reaction to obtain the modified graphene oxide. As a specific embodiment of the present invention, the silane coupling agent may include one or more of KH540 silane coupling agent, KH550 silane coupling agent, KH560 silane coupling agent, KH561 silane coupling agent, KH570 silane coupling agent, KH580 silane coupling agent and KH590 silane coupling agent, and may specifically be KH540 silane coupling agent, KH550 silane coupling agent, KH560 silane coupling agent, KH561 silane coupling agent, KH570 silane coupling agent, KH580 silane coupling agent or KH590 silane coupling agent; the mass ratio of the graphene oxide to the silane coupling agent may be 1-3:3-9, or may be 2-3:3-6, and may specifically be 1:2, 1:3 or 1:5.

[0047] The present invention has no special requirements for the mixing method, as long as it can be mixed evenly. As a specific embodiment of the present invention, the temperature of the grafting reaction can be 20 to 200°C, specifically 20°C, 50°C, 80°C, 100°C, 130°C, 150°C, 180°C or 200°C; the time of the grafting reaction can be 1 to 6 hours, specifically 1 hour, 2 hours, 3 hours, 4 hours, 5 hours or 6 hours. As a specific embodiment of the present invention, the grafting reaction can be accompanied by stirring; the stirring speed can be 100 to 1000 rpm, and can also be 400 to 500 rpm.

[0048] The present invention can improve the dispersibility of graphene oxide and its compatibility with resin by modifying the graphene oxide.

[0049] In a specific embodiment of the present invention, after the grafting reaction, the process may further include: subjecting the grafting reaction system to solid-liquid separation, and washing the solid obtained by the solid-liquid separation to obtain the modified graphene oxide. In a specific embodiment of the present invention, the solid-liquid separation may be performed by centrifugation; the washing solvent may be N-methylpyrrolidone; and the present invention can remove residual silane coupling agent through washing.

[0050] In the present invention, during the curing process, the hydroxyl groups in the resin (the epoxy resin will first open its ring to form hydroxyl groups) can undergo a polymerization reaction with the amino and / or hydroxyl groups on the surface of the modified graphene oxide, uniformly distributing the modified graphene oxide within the resin and improving the coating's performance. By introducing KGO into the polymer-based coating, the present invention inhibits the movement of molecular chains (chemical bonding inhibits the movement of the modified molecular chains, while the steric hindrance of KGO itself inhibits the movement of unreacted molecular chains), reduces PDMS wear, and provides a good load-bearing effect at the friction interface, thereby improving tribological performance. Furthermore, the stacking and staggered arrangement of the KGO flake structure creates a "maze-like" shielding structure within the coating, significantly increasing the penetration path length of the corrosive medium and thereby delaying corrosion.

[0051] In the present invention, based on the mass fraction of the resin, the component B may include 0 to 80 parts of curing agent, or 10 to 70 parts, or further 20 to 64 parts, and may specifically be 5 parts, 10 parts, 20 parts, 30 parts, 40 parts, 50 parts, 60 parts, 65 parts, 70 parts, 75 parts or 80 parts. As a specific embodiment of the present invention, the curing agent may include one or more of an amine curing agent, an acid anhydride curing agent, and a phenolic resin curing agent, and may specifically be an amine curing agent, an acid anhydride curing agent, or a phenolic resin curing agent; the amine curing agent may include ethylenediamine, diethylenetriamine, triethylenetetramine, diaminodiphenyl sulfone, or polyamide, and the polyamide may be polyamide 650 (PA650); the acid anhydride curing agent may include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, or methyltetrahydrophthalic anhydride; the phenolic resin curing agent may include p-toluenesulfonic acid, benzenesulfonic acid, or sodium petroleum sulfonate. As a specific embodiment of the present invention, when the resin is a thermosetting phenolic resin, the mass fraction of the curing agent may be 0.

[0052] In the present invention, based on the mass fraction of the resin, the component B includes 70 to 150 parts of the first organic solvent, which can be 80 to 120 parts, and can be specifically 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, 110 parts, 120 parts, 130 parts, 140 parts or 150 parts; the first organic solvent can include one or more of a lower alcohol, a benzene solvent, an ether solvent, an ester solvent and a ketone solvent; the lower alcohol can include n-butanol and / or ethanol; the benzene solvent can include xylene; the ether solvent can include petroleum ether; the ester solvent can include ethyl acetate and / or butyl acetate; the ketone solvent can include N-methylpyrrolidone (NMP), and the first organic solvent can be n-butanol, ethanol, xylene, petroleum ether, ethyl acetate, butyl acetate or N-methylpyrrolidone.

[0053] In the present invention, based on the mass fraction of the resin, component B includes 2.1 to 3.2 parts of an auxiliary agent, specifically 2.1, 2.5, 2.8, 3, or 3.2 parts. The auxiliary agent may include one or more of a defoamer, a dispersant, and a leveling agent. When the auxiliary agent is a defoamer, a dispersant, and a leveling agent, based on the mass fraction of the resin, the auxiliary agent may include 1 to 1.5 parts of a defoamer, 0.1 to 0.2 parts of a dispersant, and 1 to 1.5 parts of a leveling agent. As a specific embodiment of the present invention, the defoamer may include a silicone defoamer, a resin defoamer, a surfactant defoamer, a paraffin defoamer, or a mineral oil defoamer; the defoamer may specifically be TSA750s defoamer. As a specific embodiment of the present invention, the dispersant may include an anionic dispersant, a cationic dispersant, a nonionic dispersant, or an amphoteric dispersant; the dispersant may specifically be BYK220S dispersant. As a specific embodiment of the present invention, the leveling agent may include an organosilicon leveling agent, an acrylic leveling agent or a fluorocarbon leveling agent; the leveling agent may specifically be BYK310 leveling agent.

[0054] The method for obtaining component B of the present invention may include the following steps: dispersing modified graphene oxide in a first organic solvent and then sequentially adding a curing agent and an auxiliary agent to obtain component B. The present invention has no particular requirements for the dispersion, as long as uniform dispersion is achieved. The present invention may stir after adding the curing agent and auxiliary agent, and the stirring is not particularly required, as long as uniform mixing is achieved.

[0055] As a specific embodiment of the present invention, the preparation method of the polymer-based coating may include the following steps: mixing component A and component B to obtain the polymer-based coating. As a specific embodiment of the present invention, the mixing temperature may be room temperature, which may be 20-35°C, or 25-30°C; the mixing may be carried out under stirring, and the stirring speed may be 600-1200 rpm, specifically 600 rpm, 700 rpm, 800 rpm, 900 rpm, 1000 rpm, 1100 rpm, or 1200 rpm; the stirring time may be 5-60 min, or 10-50 min. The present invention can uniformly distribute the modified graphene oxide and additives in the coating in the resin system through stirring without agglomeration or phase separation, thereby ensuring uniform and stable coating performance. The present invention limits the stirring speed to the above range to enable the modified graphene oxide to be better dispersed in the resin matrix.

[0056] As a specific embodiment of the present invention, the mixing can be performed under vacuum conditions. The present invention utilizes a vacuum environment to defoam the mixed system. Defoaming can improve coating quality and reduce side reactions during the curing process. The present invention does not specifically limit the degree of vacuum required, as long as defoaming can be achieved.

[0057] The present invention requires the preparation of the polymer-based coating before use, and the coating is ready for use.

[0058] The present invention also provides a polymer-based lubricating coating, and the preparation method of the polymer-based lubricating coating comprises the following steps: coating the polymer-based coating described in the above technical solution on the surface of a substrate and then curing the coating to obtain the polymer-based lubricating coating.

[0059] As a specific embodiment of the present invention, the substrate may include metal, polymer, or ceramic; the metal may be steel, aluminum alloy, or copper alloy; the polymer may include polyetheretherketone or polyimide. As a specific embodiment of the present invention, the coating process may further include: pre-treating the substrate surface; the pre-treatment may include sandblasting and degreasing the substrate; the present invention does not specifically limit the sandblasting and degreasing process; conventional methods in the art may be used. The present invention can improve the bonding performance between the substrate and the polymer-based coating through pre-treatment.

[0060] The present invention has no particular requirements for the coating method, and conventional methods in the art can be used. As a specific embodiment of the present invention, the thickness of the polymer-based lubricating coating can be 5 to 50 μm, and can specifically be 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, or 50 μm. The present invention has no particular limitation on the coating thickness, as long as a polymer-based lubricating coating of the desired thickness can be obtained.

[0061] As a specific embodiment of the present invention, the curing temperature can be 40-200°C, specifically 40°C, 80°C, 100°C, 120°C, 140°C, 160°C, 180°C or 200°C; the curing holding time can be 2-5h, specifically 2h, 2.5h, 3h, 3.5h, 4h, 4.5h or 5h.

[0062] The present invention applies the polymer-based coating to the surface of a motion mechanism (metal motion mechanism), which can replace the lubricating medium while maintaining good lubricity and excellent anti-corrosion performance, so as to achieve a long-term and durable lubrication service effect.

[0063] The polymer-based coating provided by the present invention has a smooth surface, good water resistance and corrosion resistance, and a small friction coefficient, which can improve the service life and operating stability of moving parts and significantly reduce maintenance costs.

[0064] The present invention also provides the use of the polymer-based coating or the polymer-based lubricating coating described in the above technical solution in a wear-resistant component. As a specific embodiment of the present invention, the wear-resistant component can be a moving component in mechanical equipment.

[0065] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0066] Example 1

[0067] Step 1: Weigh 9.8 g of E-51 and 0.2 g of PDMS (number average molecular weight 1000 g mol -1 ), stirring at 60° C. and 300 rpm for 30 min (for polymerization reaction) to obtain a milky white polymer;

[0068] Step 2: 0.3 g of GO and 100 mL of NMP were added to a container, dispersed evenly using an ultrasonic machine, and then 0.6 mL of KH550 was added. The mixture was stirred at 80 ° C and 500 rpm for 2 h (for grafting reaction) and then centrifuged. The solid obtained by centrifugation was washed with N-methylpyrrolidone to obtain modified graphene oxide; 0.01 g of modified graphene oxide was dispersed in 12 g of N-methylpyrrolidone to obtain a KGO NMP dispersion;

[0069] Step 3: To the NMP dispersion of KGO obtained in step 2, 6.4 g of PA650 and 0.25 g of additives (0.05 g of TSA750s defoamer, 0.1 g of BYK220S dispersant, and 0.1 g of BYK310 leveling agent) were added in sequence, and stirred at 500 rpm to obtain a brown-yellow dispersion;

[0070] Step 4: Add the milky white polymer obtained in step 1 to the brown-yellow solution in step 3, and stir under vacuum at 800 rpm to obtain a polymer-based coating; place the obtained polymer-based coating in a spray gun;

[0071] Step 5: sandblasting and degreasing the steel ring to obtain a pretreated steel ring; spraying a polymer-based coating on the surface of the pretreated steel ring at a constant air pressure of 0.27 MPa and a vertical spray distance of about 25 cm;

[0072] Step 6: Place the product sprayed in step 5 in an oven and heat-cure at 80° C. for 4 hours to obtain a polymer-based coating with a thickness of 35 μm.

[0073] Example 2

[0074] Step 1: Weigh 9.8g of 2130PF (without adding curing agent) and 0.2g of PDMS (number average molecular weight of 1000gmol -1 ), stirred at 60° C. and 300 rpm for 30 min (for polymerization reaction), to obtain a yellow polymer;

[0075] Step 2: 0.3 g of GO and 100 mL of NMP were added to a container, dispersed evenly using an ultrasonic machine, and then 0.6 mL of KH550 was added. The mixture was stirred at 80°C and 500 rpm for 2 h (for grafting reaction) and then centrifuged. The solid obtained by centrifugation was washed with N-methylpyrrolidone to obtain modified graphene oxide; 0.025 g of modified graphene oxide was dispersed in 12 g of N-methylpyrrolidone to obtain a KGO NMP dispersion;

[0076] Step 3: Add 0.25 g of additives (0.05 g of TSA750s defoamer, 0.1 g of BYK220S dispersant, and 0.1 g of BYK310 leveling agent) to the KGO NMP dispersion obtained in step 2, add the mixture after stirring evenly to the yellow polymer in step 1, and stir under vacuum at 800 rpm to obtain a polymer-based coating; place the obtained polymer-based coating in a spray gun;

[0077] Step 4: sandblasting and degreasing the steel ring to obtain a pretreated steel ring; spraying the polymer-based coating on the surface of the pretreated steel ring at a constant air pressure of 0.27 MPa and a vertical spray distance of about 25 cm;

[0078] Step 5: Place the product sprayed in step 4 in an oven and heat-cure at 140° C. for 4 hours to obtain a polymer-based coating with a thickness of 35 μm.

[0079] Comparative Example 1 (no modified graphene oxide and no PDMS)

[0080] Step 1: 8 g of PA650, 12 g of NMP and 0.15 g of additives (0.05 g of TSA750s defoamer and 0.1 g of BYK310 leveling agent) were stirred at 200 rpm and uniformly mixed to obtain a yellow solution;

[0081] Step 2: Weigh 10g of E-51 and add it to the yellow solution in step 1. Stir under vacuum at 800rpm to obtain a coating. Place the obtained coating in a spray gun.

[0082] Step 3: Sandblast and degrease the steel ring to obtain a pre-treated steel ring; spray the coating on the treated steel ring surface at a constant air pressure of 0.27 MPa and a vertical spray distance of about 25 cm.

[0083] Step 4: Place the product obtained in step 3 in an oven and cure at 80°C for 4 hours to obtain a coating with a thickness of 35 μm.

[0084] Comparative Example 2 (unmodified graphene oxide)

[0085] Step 1: Weigh 9.5 g of E-51 and 0.5 g of PDMS (number average molecular weight 1000 g mol -1 ), stirring at 60° C. and 300 rpm for 30 min (for polymerization reaction) to obtain a milky white polymer;

[0086] Step 2: 8 g of PA650, 12 g of NMP and 0.15 g of additives (0.05 g of TSA750s defoamer and 0.1 g of BYK310 leveling agent) were stirred and mixed at 200 rpm to obtain a yellow solution;

[0087] Step 3: Add the milky white polymer obtained in step 1 to the yellow solution in step 2, and stir under vacuum at 800 rpm to obtain a coating; place the obtained coating in a spray gun;

[0088] Step 4: sandblasting and degreasing the steel ring to obtain a pretreated steel ring; spraying the coating on the surface of the pretreated steel ring at a constant air pressure of 0.27 MPa and a vertical spray distance of about 25 cm;

[0089] Step 5: Place the product sprayed in step 4 in an oven and heat-cure at 80° C. for 4 hours to obtain a coating with a thickness of 35 μm.

[0090] Comparative Example 3 (small amount of modified graphene oxide added)

[0091] A polymer-based coating was prepared according to the method of Example 1, except that the composition of the brown-yellow dispersion prepared in step 3 was a mixed dispersion of 0.005 g KGO and 12 g NMP, 6.4 g PA650, and 0.23 g additives (0.05 g TSA750s defoamer, 0.08 g BYK220S dispersant, and 0.1 g BYK310 leveling agent).

[0092] Comparative Example 4 (large amount of modified graphene oxide added)

[0093] A polymer-based coating was prepared according to the method of Example 1, except that the brown-yellow dispersion prepared in step 3 consisted of a mixed dispersion of 0.30 g KGO and 12 g NMP, 6.4 g PA650, and 0.32 g additives (0.05 g TSA750s defoamer, 0.17 g BYK220S dispersant, and 0.1 g BYK310 leveling agent).

[0094] The surface and longitudinal section of the polymer-based coating prepared in Example 1 were examined by scanning electron microscopy, and the Figure 1 and Figure 2 ,in Figure 1 The results of scanning electron microscopy on the surface of the polymer-based coating prepared in Example 1 are as follows: Figure 2 This is the scanning electron microscopy result of the longitudinal section of the polymer-based coating prepared in Example 1.

[0095] Combine Figure 1 and Figure 2 It can be seen that an organic silicon layer is formed on the surface of the coating, and Si(PDMS) is evenly distributed inside the coating. Therefore, the modified epoxy coating has good lubrication and anti-corrosion effects.

[0096] The surface energy of the coatings prepared in Examples 1 to 2 and Comparative Examples 1 to 4 was tested as follows:

[0097] The coating was placed on the platform of a contact angle tester (DECCA-100). The water contact angle and diiodomethane contact angle of the material surface were measured using the droplet method. A syringe was rotated to dispense 10 μL of deionized water (5 μL of diiodomethane). The droplet was then allowed to naturally contact the material surface and drip. The instrument's camera recorded the droplet's morphology and calculated the contact angle. Each coating sample surface was tested five times, and the average value was used as the final test result.

[0098] After obtaining the contact angles of the two liquids, the surface energy of the coating was calculated according to Formula 1 and Formula 2. The results are listed in Table 1. The surface energy was calculated using the Owens-Wendt-Rabel-Kaelble (OWRK) model:

[0099]

[0100] where θ represents the contact angle between the droplet and the coating surface; γ s represents the surface energy of the coating; γ l Indicates the surface tension of the liquid; represents the dispersion component of the solid; Indicates the polar component of the solid; represents the dispersion component of the liquid, Indicates the polarity of the liquid.

[0101] Table 1 Surface energy data of various embodiments and comparative examples

[0102]

[0103] As shown in Table 1, Examples 1 and 2 have extremely low surface energies, both lower than those of Comparative Examples 1 and 4. Comparing Examples 1-2 with Comparative Examples 2 and 3 reveals a slight increase in the surface energy of the Examples. This is attributed to the addition of modified graphene oxide, which inhibits the migration of PDMS to the surface, leading to an increase in the surface energy of the epoxy resin (phenolic resin), though the effect is not significant. Comparing Examples 1-2 with Comparative Examples 1 and 4 demonstrates that the prepared composite coatings exhibit improved hydrophobicity and lower surface energy compared to the Comparative Examples.

[0104] The friction coefficients of the coatings prepared in Examples 1 to 2 and Comparative Examples 1 to 4 were tested as follows:

[0105] Before testing, the cured coatings were ultrasonically cleaned with petroleum ether and scrubbed. Tribological properties were evaluated using an MRH-3 ring block testing machine (Jinan Yihua Technology Co., Ltd., China). A polytetrafluoroethylene (PTFE) block with dimensions (length × width × height) of 25 mm × 10 mm × 6 mm was used as the counter-friction member. The surface of the PTFE block was mechanically polished using sandpaper to a roughness within the range of 0.6 ± 0.05 μm. Prior to use, the PTFE block was ultrasonically cleaned to remove surface powder generated by polishing. Tribological tests were conducted under dry friction conditions with a constant load of 800 N and a sliding speed of 0.005 m / s. Each test lasted 2 h. The friction coefficient was recorded using the machine's built-in force sensor. Each test lasted 2 h, and the average friction coefficient was calculated from at least three runs.

[0106] Table 2 Friction coefficient data of various embodiments and comparative examples

[0107] Example Friction coefficient Example 1 0.01605 Example 2 0.01621 Comparative Example 1 0.04276 Comparative Example 2 0.02367 Comparative Example 3 0.02123 Comparative Example 4 0.03342

[0108] As shown in Table 2, Examples 1 and 2 have the lowest friction coefficients, both lower than the friction coefficient of the comparative example. Comparing Examples 1-2 with Comparative Examples 1-2 demonstrates the role of PDMS in coating lubrication; an appropriate amount of PDMS can significantly reduce the friction coefficient of epoxy resin (phenolic resin) coatings. Comparing Examples 1-2 with Comparative Examples 3-4 demonstrates that an appropriate amount of KGO uniformly dispersed in the coating can reduce the friction coefficient.

[0109] The anticorrosion effects of the coatings prepared in Examples 1 to 2 and Comparative Examples 1 to 4 were tested according to the following method:

[0110] The working electrode was polished with sandpaper to obtain a pretreated electrode; the coating to be tested was sprayed on the pretreated electrode surface at a constant air pressure of 0.27 MPa and a vertical spray distance of about 25 cm; the sprayed product was placed in an oven and cured at 80°C for 4 hours to obtain a coated sample electrode with a coating thickness of 35 μm.

[0111] The anti-corrosion performance was characterized using an electrochemical workstation (CHI660E, Shanghai Chenhua, China). A conventional three-electrode system was used, with a platinum wire electrode as the auxiliary electrode, a saturated calomel electrode as the reference electrode, and the coating sample electrode as the working electrode. All coating samples were immersed in a 3.5 wt% NaCl aqueous electrolyte solution for testing. The test frequency range was 10 -5 ~10 -2 , the samples after immersion for 30 days were tested, and the experimental results are shown in Table 3.

[0112] Table 3 Impedance modulus data of various embodiments and comparative examples

[0113] Example <![CDATA[Impedance modulus (Ω·cm 2 )]]> Example 1 <![CDATA[2.072×10 9 ]]> Example 2 <![CDATA[3.526×10 8 ]]> Comparative Example 1 <![CDATA[4.571×10 4 ]]> Comparative Example 2 <![CDATA[6.075×10 5 ]]> Comparative Example 3 <![CDATA[2.159×10 5 ]]> Comparative Example 4 <![CDATA[5.808×10 3 ]]>

[0114] As shown in Table 3, after immersion in NaCl solution for 30 days, Example 1 and Example 2 have the highest impedance modulus, which is much higher than the impedance modulus of the comparative example, 3 to 5 orders of magnitude higher. The examples have higher corrosion resistance. Comparing the examples with comparative examples 1 and 2, it can be seen that the role of PDMS in coating corrosion resistance is demonstrated. An appropriate amount of PDMS can improve the impedance modulus of epoxy resin (phenolic resin) coating. Comparing the examples with comparative examples 3 and 4, it can be shown that an appropriate amount of KGO uniformly dispersed in the coating can significantly improve the shielding performance of the coating, and excessive KGO can deteriorate the corrosion resistance of the coating, which is related to the agglomeration of KGO in the resin.

[0115] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A polymer-based coating, characterized in that Comprising component A and component B; The raw materials for preparing the component A include 80 to 100 parts of resin and greater than 0 and less than or equal to 5 parts of amino-terminated polydimethylsiloxane, wherein the resin includes epoxy resin and / or phenolic resin; The component B includes greater than 0.1 and less than or equal to 2 parts of modified graphene oxide, 0 to 80 parts of a curing agent, 70 to 150 parts of a first organic solvent and 2.1 to 3.2 parts of an auxiliary agent; the modified graphene oxide is graphene oxide with a silane coupling agent grafted on the surface.

2. The polymer-based coating according to claim 1, characterized in that The epoxy resin includes one or more of glycidyl ether epoxy resin, glycidyl amine epoxy resin, glycidyl ester epoxy resin and alicyclic epoxy resin; The phenolic resin includes thermoplastic phenolic resin and / or thermosetting phenolic resin; when the resin is thermosetting phenolic resin, the component B does not contain a curing agent; The number average molecular weight of the aminopolydimethylsiloxane is 500 to 10000 g / mol.

3. The polymer-based coating according to claim 1 or 2, characterized in that: The preparation method of component A comprises the following steps: Mixing the resin and aminopolydimethylsiloxane to carry out polymerization reaction to obtain the component A; The polymerization reaction temperature is 20-100° C., and the time is 10-300 minutes.

4. The polymer-based coating according to claim 1, characterized in that The preparation method of the modified graphene oxide comprises the following steps: dispersing graphene oxide in a second organic solvent to obtain a graphene oxide dispersion; The graphene oxide dispersion and the silane coupling agent are mixed to carry out a grafting reaction to obtain the modified graphene oxide.

5. The polymer-based coating according to claim 4, characterized in that: The second organic solvent includes one or more of lower alcohols, benzene solvents, ether solvents, ester solvents and ketone solvents; The solid content of the graphene oxide dispersion is 0.01 to 1%; The mass ratio of the graphene oxide to the silane coupling agent is 1-3:3-9; The grafting reaction is carried out at a temperature of 20 to 200° C. and for a time of 1 to 6 hours.

6. The polymer-based coating according to claim 1, characterized in that The curing agent includes one or more of an amine curing agent, an acid anhydride curing agent and a phenolic resin curing agent; The first organic solvent includes one or more of lower alcohols, benzene solvents, ether solvents, ester solvents and ketone solvents; The auxiliary agent includes one or more of a defoaming agent, a dispersant and a leveling agent.

7. A polymer-based lubricating coating, characterized in that The preparation method of the polymer-based lubricating coating comprises the following steps: The polymer-based lubricating coating is obtained by coating the polymer-based coating according to any one of claims 1 to 6 on the surface of a substrate and then curing the coating.

8. The polymer-based lubricating coating according to claim 7, characterized in that: The curing temperature is 40-200° C., and the heat preservation time is 2-5 hours.

9. The polymer-based lubricating coating according to claim 7 or 8, characterized in that: The thickness of the polymer-based lubricating coating is 5 to 50 μm.

10. Use of the polymer-based coating according to any one of claims 1 to 6 or the polymer-based lubricating coating according to any one of claims 7 to 9 in wear-resistant components.

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