Wear-resistant and high-temperature-resistant coating and preparation method thereof

Abstract

The invention discloses a wear-resistant and high-temperature-resistant coating, and relates to the technical field of coating materials. The preparation method comprises the following steps: firstly, oxidizing a thiol group at the tail end of polyphenylene sulfide into a sulfonic acid group, then, carrying out terminal hydroxylation treatment on the sulfo group by using 2-aminoethanol, so that the reaction activity is improved, and meanwhile, the high-temperature resistance of the coating is preliminarily improved, and then, pentafluorophenyl polyphenylene sulfide is obtained by carrying out esterification reaction on pentafluorobenzoic acid and the terminal hydroxylated polyphenylene sulfide. The chemical resistance of the coating can be improved, and the heat resistance of the coating is further improved; secondly, performing plasma bombardment treatment on basalt fibers to enable the nano SiC to be tightly combined and enhance the wear resistance, introducing a long-chain structure of hydroxyl-terminated polydimethylsiloxane through condensation reaction among hydroxyl groups, and dispersing the long-chain structure into epoxy resin emulsion to form stable siloxane-modified fiber resin emulsion; and finally, the coating formed by electrostatic spraying has strong adhesive force with the base material, so that the coating can exert wear-resistant and high-temperature-resistant effects for a long time.

Description

Technical Field

[0001] The present invention relates to the technical field of coating materials, in particular to a wear-resistant and high-temperature-resistant coating and a preparation method thereof. Background Art

[0002] With the development of high-end industrial fields such as aerospace, energy and chemical industry, higher requirements are placed on the wear resistance and high temperature resistance of materials. Early coatings were mainly achieved through simple metal spraying technology, but these coatings have limitations in wear resistance and high temperature resistance. Later, with the advancement of materials science and surface engineering technology, flame spraying, arc spraying and other technologies were born. By spraying molten ceramic or metal materials at high speed onto the surface of the substrate, wear-resistant and high-temperature resistant coatings are formed, but their application is limited by uneven coating thickness, high porosity and insufficient bonding strength. Polymer materials such as resins are used for wear-resistant coatings because of their light weight and easy processing, but they also have the disadvantage of low temperature resistance.

[0003] Coatings play a key role in industrial equipment, aerospace and high-end manufacturing, so it is particularly important to solve the problem of insufficient wear resistance and high temperature resistance. By selecting a high melting point, high hardness matrix material combined with the addition of a reinforcing phase to improve the matrix material's high temperature resistance and wear resistance, and optimizing the coating preparation process to improve the density and bonding strength of the coating, through multi-angle collaborative optimization, the problem of insufficient wear resistance and high temperature resistance of the coating is greatly improved, and the reliability and service life of the coating in extreme environments are significantly improved. Summary of the Invention

[0004] The purpose of the present invention is to provide a wear-resistant and high-temperature resistant coating and a preparation method thereof, so as to solve the problems existing in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a wear-resistant and high-temperature resistant coating and a preparation method thereof, wherein the wear-resistant and high-temperature resistant coating comprises the following preparation steps: (1) Under nitrogen protection, polyphenylene sulfide after hydrogen peroxide oxidation and N-methyl pyrrolidone are put into a reactor, heated to 70-80°C, then 2-aminoethanol is added and stirred for 2-3 hours. After the reaction is completed, it is washed with deionized water three times and dried to obtain terminal hydroxylated polyphenylene sulfide; terminal hydroxylated polyphenylene sulfide and pentafluorobenzoic acid are dissolved in anhydrous toluene, monobutyltin oxide is added, heated to 150-160°C and stirred for 2-3 hours, water vapor is condensed and removed by a condenser, cooled to room temperature, filtered and the solid is washed with saturated sodium bicarbonate solution three times, and dried to obtain pentafluorophenyl polyphenylene sulfide; (2) After the basalt fiber is subjected to plasma bombardment treatment, a modified fiber is obtained; the modified fiber and nano-SiC particles are added to anhydrous toluene and ultrasonically dispersed uniformly, and under nitrogen protection, hydroxyl-terminated polydimethylsiloxane is added, heated to 100-120°C and stirred for 5-6 hours, and the solid is filtered to obtain a siloxane-modified fiber; the siloxane-modified fiber is added to an epoxy resin emulsion, and then an alcohol ether cosolvent is added and stirred for 10 minutes, heated to 120-130°C and reacted for 6-7 hours, and the solvent is removed by vacuum distillation to obtain a siloxane-modified fiber resin emulsion; (3) Pentafluorophenyl polyphenylene sulfide is crushed in a multifunctional crusher and then electrostatically sprayed onto the substrate. After the first curing, a base coating is obtained. The silicone-modified fiber resin emulsion is electrostatically sprayed on the base coating. After the second curing, a wear-resistant and high-temperature resistant coating is obtained.

[0006] Furthermore, the preparation method of the polyphenylene sulfide after hydrogen peroxide oxidation in step (1) is as follows: sodium sulfide and p-dichlorobenzene are used as raw materials to prepare polyphenylene sulfide with an average molecular weight of 23900; the polyphenylene sulfide is placed in a 30wt% hydrogen peroxide solution, stirred and reacted at 0-10°C for 20-24h, 0.5M sodium hydroxide solution is added dropwise to pH=10, the precipitate is collected by centrifugation, washed twice with deionized water and ethanol respectively, and vacuum dried at 70°C for 24h.

[0007] Furthermore, in step (1), the mass ratio of the polyphenylene sulfide after hydrogen peroxide oxidation, N-methylpyrrolidone, and 2-aminoethanol is 190-200:500:1; and the mass ratio of the terminal hydroxylated polyphenylene sulfide, pentafluorobenzoic acid, anhydrous toluene, and monobutyltin oxide is 50-55:1:150:0.03-0.05.

[0008] Furthermore, the average particle size of the nano-SiC particles in step (2) is 50-70 nm.

[0009] Furthermore, the epoxy resin emulsion in step (2) is bisphenol A epoxy resin E-51, which is prepared by deionized water, Tween 80, and Pluronic F68 in a mass ratio of 50:47:2:1.

[0010] Furthermore, in step (2), the mass ratio of the modified fiber, nano-SiC particles, anhydrous toluene and hydroxyl-terminated polydimethylsiloxane is 0.9-1.1:0.3-0.5:3:1-1.2; and the mass ratio of the silicone-modified fiber, epoxy resin emulsion and alcohol ether cosolvent is 15-20:50:20.

[0011] Furthermore, the alcohol ether cosolvent in step (2) is ethylene glycol monopropyl ether.

[0012] Furthermore, the plasma bombardment gas in step (3) is prepared by mixing oxygen and ammonia in a mass ratio of 1:1, the bombardment power is 300 W, and the treatment time is 3 minutes.

[0013] Furthermore, the thickness of the bottom coating in step (3) is 50 μm, and the total thickness of the wear-resistant and high-temperature resistant coating is 80 μm.

[0014] Furthermore, the specific operation of the first curing in step (3) is: first curing at 140°C for 30 minutes, then curing at 230°C for 15 minutes; the specific operation of the second curing is: first curing at 110°C for 2 hours, then curing at 160°C for 2 hours, and finally curing at 220°C for 3 hours.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention prepares a base coating by electrostatically spraying pentafluorophenyl polyphenylene sulfide resin and prepares a closing coating by fiber-modified epoxy resin. The base coating and the closing coating form a wear-resistant and high-temperature resistant coating to achieve wear-resistant and high-temperature resistant effects.

[0016] First, polyphenylene sulfide is prepared using sodium sulfide and paradichlorobenzene as raw materials, and the thiol group at the end of the polyphenylene sulfide is oxidized to a sulfonic acid group using hydrogen peroxide. The polyphenylene sulfide is then terminally hydroxylated using 2-aminoethanol. The reaction of the sulfonic acid group with the amino group introduces a hydroxyl group, which improves the reactivity of the polyphenylene sulfide. The presence of the terminally hydroxylated polyphenylene sulfide makes the coating less likely to decompose at high temperatures, thereby preliminarily improving the high-temperature resistance of the coating. The terminally hydroxylated polyphenylene sulfide is then modified using pentafluorobenzoic acid, and pentafluorophenyl polyphenylene sulfide is obtained by esterification between the carboxyl group of pentafluorobenzoic acid and the hydroxyl group of the terminally hydroxylated polyphenylene sulfide. The perfluorinated aromatic ring not only reduces the surface energy of the coating and improves the chemical resistance of the coating, but also further improves the heat resistance of the coating. The pentafluorophenyl polyphenylene sulfide particles are then deposited on the surface of the substrate using an electrostatic spraying process to form a base coating. The base coating has a uniform thickness, shortens the coating curing time, and enhances the adhesion between the base coating and the substrate, thereby allowing the coating to function for a long time.

[0017] Finally, the basalt fiber was treated with plasma bombardment to introduce hydroxyl and amino groups on the surface of the basalt fiber and increase the porosity, so that the nano-SiC can be embedded in the porous network structure on the surface of the basalt fiber, preventing the nano-SiC from being destroyed, thereby enhancing the wear resistance of the modified fiber; the long-chain structure of hydroxyl-terminated polydimethylsiloxane was introduced into the modified fiber through the condensation reaction of hydroxyl and hydroxyl groups, and the obtained siloxane-modified fiber avoided the cracking phenomenon caused by stress concentration in the closed coating, further enhancing the stability of the coating; the presence of amino groups can improve the compatibility of siloxane-modified fiber with epoxy resin emulsion, and the siloxane-modified fiber is grafted onto the epoxy resin through the ring-opening reaction of amino groups and epoxy groups. The cross-linked structure formed can increase the hardness of the coating and reduce the wear of the underlying coating; the synergistic protective effect of the underlying coating and the closed coating effectively extends the service life of the substrate. DETAILED DESCRIPTION

[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0019] In order to more clearly illustrate the method provided by the present invention, the following examples are used to describe in detail the various index testing methods of a wear-resistant and high-temperature resistant coating prepared in the following examples. Wear resistance: Take the coating material of the same size to test its wear resistance. The grinding material is a 4mm diameter GCr15 steel ball. Under the condition of motor speed of 500r / min and load of 3N, the test is carried out for 15 minutes, and the mass loss rate is calculated. Heat resistance: Take the coating materials of the same size and use a comprehensive performance analyzer to test the heat resistance performance. Keep it at 500℃ for 20 minutes, and calculate its mass retention rate based on the mass before and after the thermal change. Adhesion: According to ASTM D4541, a pull-off adhesion tester is used. A 10mm diameter cylindrical test rod is bonded to the coating surface. A tensile force perpendicular to the surface is applied. The tensile force is recorded when the substrate and coating separate. The adhesion of the coating is calculated based on the tensile force and the area of ​​the test rod. Example 1

[0020] (1) By weight, 10 parts of sodium sulfide and 45 parts of N-methylpyrrolidone were mixed in a reactor. Under nitrogen protection, the temperature was raised to 200°C for evaporation and dehydration for 2 hours to obtain a sodium sulfide solution. 16 parts of p-dichlorobenzene and 5 parts of sodium hydroxide were added, and then the temperature was raised to 260°C. The mixture was stirred at 100 rpm for 3.5 hours. 50 parts of deionized water was added. After cooling to room temperature, the solid was filtered, washed with deionized water 3 times, and dried at 80°C for 8 hours. Polyphenylene sulfide with an average molecular weight of 23900 was obtained; 230 parts of polyphenylene sulfide were placed in 3 parts of 30wt% hydrogen peroxide solution, 500 parts of deionized water were added, and the mixture was stirred at 0°C for 20 hours. A 0.5M sodium hydroxide solution was added dropwise to a pH of 10, and the mixture was centrifuged at 8000 rpm for 15 minutes. The precipitate was collected and washed twice with deionized water and ethanol, and dried at 70°C and -0.1 MPa for 24 hours to obtain polyphenylene sulfide after hydrogen peroxide oxidation; (2) In parts by mass, under nitrogen protection, 190 parts of polyphenylene sulfide after hydrogen peroxide oxidation and 500 parts of N-methylpyrrolidone were put into a reactor, heated to 70°C, and then 1 part of 2-aminoethanol was added and stirred at 300 rpm for 2 hours. After the reaction, it was washed with deionized water 3 times and dried at 60°C for 12 hours to obtain terminal hydroxylated polyphenylene sulfide; 50 parts of terminal hydroxylated polyphenylene sulfide and 1 part of pentafluorobenzoic acid were dissolved in 150 parts of anhydrous toluene, 0.03 parts of monobutyltin oxide were added, heated to 150°C, stirred at 150 rpm for 2 hours, and the water vapor was condensed and removed by a condenser. After cooling to room temperature, the solid was filtered and washed with saturated sodium bicarbonate solution 3 times, and dried at 80°C for 10 hours to obtain pentafluorophenyl polyphenylene sulfide; (3) In terms of mass parts, oxygen and ammonia were mixed in a mass ratio of 1:1 to prepare plasma bombardment gas, and basalt fiber was subjected to plasma bombardment treatment at a power of 300 W for 3 minutes to obtain modified fiber; 9 parts of modified fiber and 3 parts of SiC particles with an average particle size of 50 nm were added to 30 parts of anhydrous toluene and ultrasonically dispersed for 8 minutes at an ultrasonic power of 2400 W. Under nitrogen protection, 10 parts of hydroxyl-terminated polydimethylsiloxane were added, and the mixture was heated to 100 ° C and stirred at a speed of 100 rpm for 5 hours. After the reaction was completed, the solid was filtered to obtain siloxane-modified fiber; (4) By weight, 50 parts of bisphenol A epoxy resin E-51, 2 parts of Tween 80, and 1 part of Pluronic F68 were added to a reactor, heated to 75°C, stirred at 75 rpm for 5 minutes, then added with 47 parts of deionized water and stirred at 2000 rpm for 2 hours, and cooled to room temperature to obtain an epoxy resin emulsion; 15 parts of silicone-modified fiber were added to 50 parts of epoxy resin emulsion, then added with 20 parts of ethylene glycol monopropyl ether and stirred at 50 rpm for 10 minutes, heated to 120°C for reaction for 6 hours, and distilled to remove the solvent at 20 kPa and 70°C to obtain a silicone-modified fiber resin emulsion; (5) The metal substrate was surface-polished with 200-mesh sandpaper, and 100 parts of pentafluorophenyl polyphenylene sulfide were placed in a multifunctional crusher and stirred at a speed of 1500 rpm for 15 minutes. After crushing, the powder was electrostatically sprayed on the surface-treated substrate at an external voltage of 20 kV and a receiving distance of 13 cm. The workpiece was then placed in an oven and cured at 140 ° C for 30 minutes and then at 230 ° C for 15 minutes to obtain a base coating with a thickness of 30 μm. Then, 150 parts of silicone-modified fiber resin emulsion were electrostatically sprayed on the base coating at an external voltage of 20 kV and a receiving distance of 13 cm. The workpiece was placed in an oven again and cured at 110 ° C for 2 hours, then at 160 ° C for 2 hours, and finally at 220 ° C for 3 hours to obtain a wear-resistant and high-temperature resistant coating with a thickness of 80 μm. Example 2

[0021] (1) By weight, 10 parts of sodium sulfide and 45 parts of N-methylpyrrolidone were mixed in a reactor. Under nitrogen protection, the temperature was raised to 200°C for evaporation and dehydration for 2 hours to obtain a sodium sulfide solution. 16 parts of p-dichlorobenzene and 5 parts of sodium hydroxide were added, and then the temperature was raised to 260°C. The mixture was stirred at 100 rpm for 3.5 hours. 50 parts of deionized water was added. After cooling to room temperature, the solid was filtered, washed with deionized water 3 times, and dried at 80°C for 8 hours. Polyphenylene sulfide with an average molecular weight of 23900 was obtained; 230 parts of polyphenylene sulfide were placed in 3 parts of 30wt% hydrogen peroxide solution, 500 parts of deionized water were added, and the mixture was stirred at 5°C for 22 hours. A 0.5M sodium hydroxide solution was added dropwise to a pH of 10, and the mixture was centrifuged at 8000 rpm for 15 minutes. The precipitate was collected and washed twice with deionized water and ethanol, and dried at 70°C and -0.1 MPa for 24 hours to obtain polyphenylene sulfide after hydrogen peroxide oxidation; (2) In parts by mass, under nitrogen protection, 195 parts of polyphenylene sulfide after hydrogen peroxide oxidation and 500 parts of N-methylpyrrolidone were put into a reactor, heated to 75°C, and then 1 part of 2-aminoethanol was added and stirred at 300 rpm for 2.5 hours. After the reaction, it was washed with deionized water 3 times and dried at 60°C for 12 hours to obtain terminal hydroxylated polyphenylene sulfide; 52.5 parts of terminal hydroxylated polyphenylene sulfide and 1 part of pentafluorobenzoic acid were dissolved in 150 parts of anhydrous toluene, 0.04 parts of monobutyltin oxide were added, heated to 155°C, stirred at 150 rpm for 2.5 hours, and the water vapor was condensed and removed by a condenser. After cooling to room temperature, the solid was filtered and washed with saturated sodium bicarbonate solution 3 times, and dried at 80°C for 10 hours to obtain pentafluorophenyl polyphenylene sulfide; (3) In terms of mass parts, oxygen and ammonia were mixed in a mass ratio of 1:1 to prepare plasma bombardment gas, and basalt fiber was subjected to plasma bombardment treatment at a power of 300 W for 3 minutes to obtain modified fiber; 10 parts of modified fiber and 4 parts of SiC particles with an average particle size of 60 nm were added to 30 parts of anhydrous toluene and ultrasonically dispersed for 8 minutes at an ultrasonic dispersion power of 2400 W. Under nitrogen protection, 11 parts of hydroxyl-terminated polydimethylsiloxane were added, and the mixture was heated to 110°C and stirred at a speed of 100 rpm for 5.5 hours. After the reaction was completed, the solid was filtered to obtain siloxane-modified fiber; (4) By weight, 50 parts of bisphenol A epoxy resin E-51, 2 parts of Tween 80, and 1 part of Pluronic F68 were added to a reactor, heated to 75°C, stirred at 75 rpm for 5 minutes, then added with 47 parts of deionized water and stirred at 2000 rpm for 2 hours, and cooled to room temperature to obtain an epoxy resin emulsion; 17.5 parts of silicone-modified fiber were added to 50 parts of epoxy resin emulsion, then added with 20 parts of ethylene glycol monopropyl ether and stirred at 50 rpm for 10 minutes, heated to 125°C and reacted for 6.5 hours, and the solvent was distilled off at 20 kPa and 70°C to obtain a silicone-modified fiber resin emulsion; (5) The metal substrate was surface-polished with 200-mesh sandpaper, and 100 parts of pentafluorophenyl polyphenylene sulfide were placed in a multifunctional crusher and stirred at a speed of 1500 rpm for 15 minutes. After crushing, the powder was electrostatically sprayed on the surface-treated substrate at an external voltage of 20 kV and a receiving distance of 13 cm. The workpiece was then placed in an oven and cured at 140 ° C for 30 minutes and then at 230 ° C for 15 minutes to obtain a base coating with a thickness of 30 μm. Then, 150 parts of silicone-modified fiber resin emulsion were electrostatically sprayed on the base coating at an external voltage of 20 kV and a receiving distance of 13 cm. The workpiece was placed in an oven again and cured at 110 ° C for 2 hours, then at 160 ° C for 2 hours, and finally at 220 ° C for 3 hours to obtain a wear-resistant and high-temperature resistant coating with a thickness of 80 μm. Example 3

[0022] (1) By weight, 10 parts of sodium sulfide and 45 parts of N-methylpyrrolidone were mixed in a reactor. Under nitrogen protection, the temperature was raised to 200°C for evaporation and dehydration for 2 hours to obtain a sodium sulfide solution. 16 parts of p-dichlorobenzene and 5 parts of sodium hydroxide were added, and then the temperature was raised to 260°C. The mixture was stirred at 100 rpm for 3.5 hours. 50 parts of deionized water was added. After cooling to room temperature, the solid was filtered, washed with deionized water 3 times, and dried at 80°C for 8 hours. Polyphenylene sulfide with an average molecular weight of 23900 was obtained; 230 parts of polyphenylene sulfide were placed in 3 parts of 30wt% hydrogen peroxide solution, 500 parts of deionized water were added, and the mixture was stirred at 10°C for 24 hours. A 0.5M sodium hydroxide solution was added dropwise to a pH of 10, and the mixture was centrifuged at 8000 rpm for 15 minutes. The precipitate was collected and washed twice with deionized water and ethanol, and dried at 70°C and -0.1 MPa for 24 hours to obtain polyphenylene sulfide after hydrogen peroxide oxidation; (2) In parts by mass, under nitrogen protection, 200 parts of polyphenylene sulfide after hydrogen peroxide oxidation and 500 parts of N-methylpyrrolidone were put into a reactor, heated to 80°C, and then 1 part of 2-aminoethanol was added and stirred at 300 rpm for 2.5 hours. After the reaction, it was washed with deionized water 3 times and dried at 60°C for 12 hours to obtain terminal hydroxylated polyphenylene sulfide; 55 parts of terminal hydroxylated polyphenylene sulfide and 1 part of pentafluorobenzoic acid were dissolved in 150 parts of anhydrous toluene, 0.05 parts of monobutyltin oxide were added, heated to 160°C, stirred at 150 rpm for 3 hours, and the water vapor was condensed and removed by a condenser. After cooling to room temperature, the solid was filtered and washed with saturated sodium bicarbonate solution 3 times, and dried at 80°C for 10 hours to obtain pentafluorophenyl polyphenylene sulfide; (3) In terms of mass parts, oxygen and ammonia were mixed in a mass ratio of 1:1 to prepare plasma bombardment gas, and basalt fiber was subjected to plasma bombardment treatment at a power of 300 W for 3 minutes to obtain modified fiber; 11 parts of modified fiber and 5 parts of SiC particles with an average particle size of 70 nm were added to 30 parts of anhydrous toluene and ultrasonically dispersed for 8 minutes at an ultrasonic dispersion power of 2400 W. Under nitrogen protection, 12 parts of hydroxyl-terminated polydimethylsiloxane were added, and the mixture was heated to 120°C and stirred at a speed of 100 rpm for 6 hours. After the reaction was completed, the solid was filtered to obtain siloxane-modified fiber; (4) By weight, 50 parts of bisphenol A epoxy resin E-51, 2 parts of Tween 80, and 1 part of Pluronic F68 were added to a reactor, heated to 75°C, stirred at 75 rpm for 5 minutes, then added with 47 parts of deionized water and stirred at 2000 rpm for 2 hours, and cooled to room temperature to obtain an epoxy resin emulsion; 20 parts of silicone-modified fiber were added to 50 parts of epoxy resin emulsion, then added with 20 parts of ethylene glycol monopropyl ether and stirred at 50 rpm for 10 minutes, heated to 130°C for reaction for 7 hours, and distilled to remove the solvent at 20 kPa and 70°C to obtain a silicone-modified fiber resin emulsion; (5) The metal substrate was surface-polished with 200-mesh sandpaper, and 100 parts of pentafluorophenyl polyphenylene sulfide were placed in a multifunctional crusher and stirred at a speed of 1500 rpm for 15 minutes. After crushing, the powder was electrostatically sprayed on the surface-treated substrate at an external voltage of 20 kV and a receiving distance of 13 cm. The workpiece was then placed in an oven and cured at 140 ° C for 30 minutes and then at 230 ° C for 15 minutes to obtain a base coating with a thickness of 30 μm. Then, 150 parts of silicone-modified fiber resin emulsion were electrostatically sprayed on the base coating at an external voltage of 20 kV and a receiving distance of 13 cm. The workpiece was placed in an oven again and cured at 110 ° C for 2 hours, then at 160 ° C for 2 hours, and finally at 220 ° C for 3 hours to obtain a wear-resistant and high-temperature resistant coating with a thickness of 80 μm.

[0023] Comparative Example 1 The difference between Comparative Example 1 and Example 2 is that there is no step (2), and step (1) is changed to: by weight, 10 parts of sodium sulfide and 45 parts of N-methylpyrrolidone are mixed in a reactor, and under nitrogen protection, the temperature is raised to 200°C for evaporation and dehydration for 2 hours to obtain a sodium sulfide solution, 16 parts of p-dichlorobenzene and 5 parts of sodium hydroxide are added, and then the temperature is raised to 260°C, and the reaction is stirred at a speed of 100 rpm for 3.5 hours, 50 parts of deionized water are added, and after cooling to room temperature, the solid is filtered and washed with deionized water 3 times, and dried at 80°C for 8 hours to obtain polyphenylene sulfide with an average molecular weight of 23900; step (5) is changed to: by weight, the metal substrate is surface-polished with 200-mesh sandpaper, 100 parts of polyphenylene sulfide are placed in a multifunctional The mixture was stirred at a speed of 1500 rpm in a crusher for 15 minutes. After crushing, the powder was electrostatically sprayed on the surface-treated substrate at an applied voltage of 20 kV and a receiving distance of 13 cm. The workpiece was then placed in an oven and cured at 140°C for 30 minutes and then at 230°C for 15 minutes to obtain a base coating with a thickness of 30 μm. Then, 150 parts of a silicone-modified fiber resin emulsion were electrostatically sprayed on the base coating at an applied voltage of 20 kV and a receiving distance of 13 cm. The workpiece was placed in an oven again and cured at 110°C for 2 hours, then at 160°C for 2 hours, and finally at 220°C for 3 hours to obtain a wear-resistant and high-temperature resistant coating with a thickness of 80 μm. The remaining steps were the same as in Example 2.

[0024] Comparative Example 2 The difference between Comparative Example 2 and Example 2 lies in the difference between steps (2) and (5). Step (2) is changed to: in parts by mass, under nitrogen protection, 195 parts of polyphenylene sulfide after hydrogen peroxide oxidation and 500 parts of N-methylpyrrolidone are put into a reactor, heated to 75°C, then 1 part of 2-aminoethanol is added and stirred at 300 rpm for 2.5 hours. After the reaction is completed, it is washed with deionized water 3 times and dried at 60°C for 12 hours to obtain terminal hydroxylated polyphenylene sulfide; 52.5 parts of terminal hydroxylated polyphenylene sulfide and 1 part of formic acid are dissolved in 150 parts of anhydrous toluene, 0.04 parts of monobutyltin oxide are added, the mixture is heated to 155°C and stirred at 150 rpm for 2.5 hours, the water vapor is condensed and removed by a condenser, and after cooling to room temperature, the solid is filtered and washed 3 times with a saturated sodium bicarbonate solution, and dried at 80°C for 10 hours to obtain formic acid-modified polyphenylene sulfide; step (5) is changed to: : In parts by mass, the metal substrate was surface-polished with 200-mesh sandpaper, 100 parts of formic acid-modified polyphenylene sulfide were placed in a multifunctional crusher and stirred at a speed of 1500 rpm for 15 minutes, and after crushing, the powder was electrostatically sprayed on the surface-treated substrate under the parameters of an applied voltage of 20 kV and a receiving distance of 13 cm, and then the workpiece was placed in an oven, first cured at 140° C. for 30 minutes, and then cured at 230° C. for 15 minutes to obtain a base coating with a thickness of 30 μm; then 150 parts of a silicone-modified fiber resin emulsion were electrostatically sprayed on the base coating under the parameters of an applied voltage of 20 kV and a receiving distance of 13 cm, and the workpiece was placed in an oven again, first cured at 110° C. for 2 hours, then cured at 160° C. for 2 hours, and finally cured at 220° C. for 3 hours to obtain a wear-resistant and high-temperature resistant coating with a thickness of 80 μm; the remaining steps were the same as in Example 2.

[0025] Comparative Example 3 The difference between Comparative Example 3 and Example 2 lies in the differences in steps (3), (4) and (5). Step (3) is changed to: by weight, 10 parts of basalt fiber and 4 parts of SiC particles with an average particle size of 60 nm are added to 30 parts of anhydrous toluene and ultrasonically dispersed for 8 minutes at an ultrasonic power of 2400 W to obtain nano-SiC-basalt fiber; step (4) is changed to: by weight, 50 parts of bisphenol A epoxy resin E-51, 2 parts of Tween 80, 1 part of Pluronic F68 was put into a reactor, heated to 75°C, stirred at 75 rpm for 5 minutes, then 47 parts of deionized water were added and stirred at 2000 rpm for 2 hours, and then cooled to room temperature to obtain an epoxy resin emulsion; 17.5 parts of nano-SiC-basalt fiber were put into 50 parts of epoxy resin emulsion, then 20 parts of ethylene glycol monopropyl ether were added and stirred at 50 rpm for 10 minutes, heated to 125°C for reaction for 6.5 hours, and the solvent was distilled off at 20 kPa and 70°C to obtain a nano-SiC-basalt fiber resin emulsion; step (5) was changed to: in parts by mass, the metal substrate was surface-polished with 200-mesh sandpaper, 100 parts of pentafluorophenyl polyphenylene sulfide were put into a multi-functional crusher and stirred at 15 The powder was stirred at a speed of 00 rpm for 15 minutes. After crushing, the powder was electrostatically sprayed on the surface-treated substrate at an applied voltage of 20 kV and a receiving distance of 13 cm. The workpiece was then placed in an oven and cured at 140° C. for 30 minutes and then at 230° C. for 15 minutes to obtain a base coating with a thickness of 30 μm. Then, 150 parts of nano-SiC-basalt fiber resin emulsion were electrostatically sprayed on the base coating at an applied voltage of 20 kV and a receiving distance of 13 cm. The workpiece was placed in an oven again and cured at 110° C. for 2 hours, then at 160° C. for 2 hours, and finally at 220° C. for 3 hours to obtain a wear-resistant and high-temperature resistant coating with a thickness of 80 μm. The remaining steps were the same as in Example 2.

[0026] Comparative Example 4 The difference between Comparative Example 4 and Example 2 lies in the difference in steps (3), (4) and (5). Step (3) is changed to: in parts by mass, oxygen and ammonia are mixed in a mass ratio of 1:1 to prepare plasma bombardment gas, and the basalt fiber is subjected to plasma bombardment treatment for 3 minutes at a power of 300W to prepare modified fiber; 10 parts of modified fiber and 4 parts of SiC particles with an average particle size of 60nm are added to 30 parts of anhydrous toluene and ultrasonically dispersed for 8 minutes at an ultrasonic power of 2400W to prepare nano-SiC-modified fiber; step (4) is changed to: in parts by mass, 50 parts of bisphenol A epoxy resin E-51, 2 parts of Tween 80, 1 part of Pluronic F68 was put into a reactor, heated to 75°C, stirred at 75 rpm for 5 minutes, then 47 parts of deionized water were added and stirred at 2000 rpm for 2 hours, and then cooled to room temperature to obtain an epoxy resin emulsion; 17.5 parts of nano-SiC-modified fiber were put into 50 parts of epoxy resin emulsion, then 20 parts of ethylene glycol monopropyl ether were added and stirred at 50 rpm for 10 minutes, heated to 125°C for reaction for 6.5 hours, and the solvent was distilled off at 20 kPa and 70°C to obtain a nano-SiC-modified fiber resin emulsion; step (5) was changed to: in parts by mass, the metal substrate was surface-polished with 200-mesh sandpaper, 100 parts of pentafluorophenyl polyphenylene sulfide were put into a multi-functional crusher and stirred at 150 The reaction mixture was stirred at a speed of 0 rpm for 15 min. After pulverization, the powder was electrostatically sprayed on the surface-treated substrate at an applied voltage of 20 kV and a receiving distance of 13 cm. The workpiece was then placed in a baking oven, first cured at 140 ° C for 30 min, and then cured at 230 ° C for 15 min to obtain a base coat with a thickness of 30 μm. The applied voltage was then 20 kV, and the receiving distance was 13 cm. 150 parts of nano-SiC-modified fiber resin emulsions were electrostatically sprayed on the base coat. The workpiece was again placed in a baking oven, first cured at 110 ° C for 2 h, then cured at 160 ° C for 2 h, and finally cured at 220 ° C for 3 h to obtain a wear-resistant and high-temperature resistant coating with a thickness of 80 μm. The remaining steps were the same as in Example 2.

[0027] Effect Examples Table 1 below shows the performance analysis results of a wear-resistant and high-temperature resistant coating using Examples 1 to 3 of the present invention and Comparative Examples 1 to 4.

[0028] Table 1

[0029] From the comparison of the wear resistance experimental data of the embodiment and the comparative example, it can be found that after the plasma bombardment treatment of the basalt fiber, the present invention introduces hydroxyl groups on the surface of the basalt fiber and increases the porosity, so that the nano-SiC can be embedded in the porous network structure on the surface of the basalt fiber, preventing the nano-SiC from being destroyed, thereby enhancing the wear resistance of the coating, and the long chain structure of the hydroxyl-terminated polydimethylsiloxane is introduced into the modified fiber, and the prepared siloxane-modified fiber avoids the cracking phenomenon caused by stress concentration in the closed coating, enhances the stability of the coating, and increases the wear resistance of the coating; From the comparison of the wear resistance experimental data of the embodiment and the comparative example, It can be found that 2-aminoethanol and pentafluorobenzoic acid have a significant modification effect on polyphenylene sulfide. The reaction between the sulfonic acid group and the amino group improves the reactivity of the polyphenylene sulfide and preliminarily improves the high temperature resistance of the coating. The esterification reaction between the carboxyl group of pentafluorobenzoic acid and the hydroxyl group of the terminal hydroxylated polyphenylene sulfide to obtain pentafluorophenyl polyphenylene sulfide improves the stability of the coating and further improves the heat resistance of the coating. From the comparison of the experimental data of the adhesion of the embodiment and the comparative example, it can be found that the use of an electrostatic spraying process for pentafluorophenyl polyphenylene sulfide and a silicone-modified fiber resin emulsion can enhance the adhesion between the coating and the substrate, thereby allowing the coating to function for a long time.

[0030] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed therein. Any reference in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A wear-resistant and high-temperature resistant coating and a preparation method thereof, characterized in that: The wear-resistant and high-temperature resistant coating comprises the following preparation steps: (1) Under nitrogen protection, polyphenylene sulfide after hydrogen peroxide oxidation and N-methyl pyrrolidone are put into a reactor, heated to 70-80°C, then 2-aminoethanol is added and stirred for 2-3 hours. After the reaction is completed, it is washed with deionized water three times and dried to obtain terminal hydroxylated polyphenylene sulfide; terminal hydroxylated polyphenylene sulfide and pentafluorobenzoic acid are dissolved in anhydrous toluene, monobutyltin oxide is added, heated to 150-160°C and stirred for 2-3 hours, water vapor is condensed and removed by a condenser, cooled to room temperature, filtered and the solid is washed with saturated sodium bicarbonate solution three times, and dried to obtain pentafluorophenyl polyphenylene sulfide; (2) After plasma bombardment treatment of basalt fiber, modified fiber was obtained; The modified fiber and nano-SiC particles are added to anhydrous toluene and ultrasonically dispersed uniformly. Under nitrogen protection, hydroxyl-terminated polydimethylsiloxane is added, and the mixture is heated to 100-120°C and stirred for 5-6 hours. The solid is filtered to obtain a siloxane-modified fiber. The siloxane-modified fiber is added to an epoxy resin emulsion, and then an alcohol ether cosolvent is added and stirred for 10 minutes. The mixture is heated to 120-130°C and reacted for 6-7 hours. The solvent is removed by distillation under reduced pressure to obtain a siloxane-modified fiber resin emulsion. (3) Pentafluorophenyl polyphenylene sulfide is crushed in a multifunctional crusher and then electrostatically sprayed onto the substrate. After the first curing, a base coating is obtained. The silicone-modified fiber resin emulsion is electrostatically sprayed on the base coating. After the second curing, a wear-resistant and high-temperature resistant coating is obtained.

2. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: The preparation method of the polyphenylene sulfide after hydrogen peroxide oxidation in step (1) is as follows: sodium sulfide and p-dichlorobenzene are used as raw materials to prepare polyphenylene sulfide with an average molecular weight of 23900; the polyphenylene sulfide is placed in a 30wt% hydrogen peroxide solution, stirred and reacted at 0-10°C for 20-24h, 0.5M sodium hydroxide solution is added dropwise to pH=10, the precipitate is collected by centrifugation, washed twice with deionized water and ethanol respectively, and vacuum dried at 70°C for 24h.

3. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: In step (1), the mass ratio of the polyphenylene sulfide after hydrogen peroxide oxidation, N-methylpyrrolidone, and 2-aminoethanol is 190-200:500:1; the mass ratio of the terminal hydroxylated polyphenylene sulfide, pentafluorobenzoic acid, anhydrous toluene, and monobutyltin oxide is 50-55:1:150:0.03-0.

05.

4. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: The average particle size of the nano-SiC particles in step (2) is 50-70 nm.

5. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: The epoxy resin emulsion in step (2) is bisphenol A epoxy resin E-51, which is prepared by deionized water, Tween 80, and Pluronic F68 in a mass ratio of 50:47:2:

1.

6. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: In step (2), the mass ratio of the modified fiber, nano-SiC particles, anhydrous toluene and hydroxyl-terminated polydimethylsiloxane is 0.9-1.1:0.3-0.5:3:1-1.2; the mass ratio of the silicone-modified fiber, epoxy resin emulsion and alcohol ether cosolvent is 15-20:50:

20.

7. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: The alcohol ether cosolvent in step (2) is ethylene glycol monopropyl ether.

8. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: The plasma bombardment gas in step (3) is a mixture of oxygen and ammonia in a mass ratio of 1:1, the bombardment power is 300 W, and the treatment time is 3 minutes.

9. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: The thickness of the bottom coating in step (3) is 50 μm, and the total thickness of the wear-resistant and high-temperature resistant coating is 80 μm.

10. The wear-resistant and high-temperature resistant coating and preparation method thereof according to claim 1, characterized in that: The specific operation of the first curing in step (3) is: first curing at 140°C for 30 minutes, then curing at 230°C for 15 minutes; the specific operation of the second curing is: first curing at 110°C for 2 hours, then curing at 160°C for 2 hours, and finally curing at 220°C for 3 hours.

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