CN-118027779-B - Corrosion-resistant wear-resistant epoxy coating and preparation method thereof

CN118027779BCN 118027779 BCN118027779 BCN 118027779BCN-118027779-B

Abstract

The invention discloses a corrosion-resistant and wear-resistant epoxy coating which is prepared from the following raw materials, by mass, 1-5 parts of carbon nanotubes, 5-10 parts of chopped carbon fibers, 10-20 parts of silicon carbide powder, 80-150 parts of dimethylformamide solvent, 100-200 parts of epoxy resin, 100-200 parts of curing agent and 1-2 parts of leveling agent. The invention also discloses a preparation method of the corrosion-resistant and wear-resistant epoxy coating, which is used for carrying out surface modification on the carbon nano tube, the silicon carbide and the chopped carbon fiber, preparing the composite modified epoxy coating of the carbon nano tube/the chopped carbon fiber/the silicon carbide and preparing the corrosion-resistant and wear-resistant epoxy coating by utilizing the composite modified epoxy coating. The epoxy coating prepared by the invention can ensure that the coating has the performances of corrosion resistance, wear resistance, crack resistance and the like, greatly prolongs the service life of the coating in complex environments, and has important theoretical significance and engineering application value.

Inventors

ZHANG WEIQIANG
GAO LEI
WANG TONGPING
ZHANG JINGBIN
CHEN XIFENG
YANG YAN

Assignees

中国船舶集团有限公司第十二研究所

Dates

Publication Date: 20260505
Application Date: 20240119

Claims (10)

1. The corrosion-resistant and wear-resistant epoxy coating is characterized by being prepared from the following raw materials, by mass, 1-5 parts of carbon nanotubes, 5-10 parts of chopped carbon fibers, 10-20 parts of silicon carbide powder, 80-150 parts of dimethylformamide solvent, 100-200 parts of epoxy resin, 100-200 parts of curing agent and 1-2 parts of leveling agent; the surface modification method of the carbon nano tube comprises the following steps: Preparing a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid, adding a carbon nano tube, carrying out ultrasonic oscillation for 0.5-1 h, filtering, washing the carbon nano tube with deionized water, and finally filtering and drying at 50-80 ℃ to obtain carboxylated carbon nano tubes, wherein the ratio of the concentrated sulfuric acid to the concentrated nitric acid in the mixed acid solution is 3:1, the mass concentration of the concentrated sulfuric acid is 95-98%, and the mass concentration of the concentrated nitric acid is 65-68%; Step 1.2, dissolving carboxylated carbon nanotubes in a tris buffer solution, carrying out ultrasonic oscillation for 0.5-1 h until the mixture is uniformly mixed to obtain a carbon nanotube aqueous suspension, then adding dopamine hydrochloride, carrying out mechanical stirring for full reaction, and filtering to obtain polydopamine coated carbon nanotubes; Step 1.3, adding the polydopamine coated carbon nano tube into hydrochloric acid and aniline with the concentration of 0.5mol/L, performing mechanical stirring reaction to form uniform suspension, then adding ammonium persulfate solution, and continuously performing oxidative polymerization reaction for 4-10 hours in an ice bath; The method for modifying the surface of the silicon carbide and the chopped carbon fiber comprises the following steps: Step 2.1, preparing an ethanol water solution, wherein the volume ratio of ethanol to deionized water is 4:1; Step 2.2, respectively dispersing silicon carbide with the particle size of 5-75 mu m and chopped carbon fibers with the diameter of 7 mu m and the length of 0.1-0.5 mm in a xylene solution, and carrying out ultrasonic oscillation homogenization treatment to respectively obtain a silicon carbide solution and a chopped carbon fiber solution; And 2.3, respectively adding the solutions obtained in the step 2.2 into the solutions obtained in the step 2.1 for reaction, filtering to obtain silicon carbide and chopped carbon fibers, washing the silicon carbide and chopped carbon fibers with alcohol, and then drying in vacuum.
2. The corrosion and abrasion resistant epoxy coating of claim 1, wherein the epoxy resin is E44, the curing agent is polyamide 650, and the leveling agent is BYK306.
3. The preparation method of the corrosion-resistant and wear-resistant epoxy coating is characterized by comprising the following specific steps: step 1, carrying out surface modification on a carbon nano tube; Step 2, modifying the surface of the silicon carbide and the chopped carbon fiber; Step 3, preparing a composite modified epoxy coating of the carbon nano tube/chopped carbon fiber/silicon carbide; And 4, preparing the corrosion-resistant and wear-resistant epoxy coating by using the composite modified epoxy coating.
4. The method for preparing the corrosion-resistant and wear-resistant epoxy coating according to claim 3, wherein the step 1 is specifically as follows: Preparing a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid, adding a carbon nano tube, carrying out ultrasonic oscillation for 0.5-1 h, filtering, washing the carbon nano tube with deionized water, and finally filtering and drying at 50-80 ℃ to obtain carboxylated carbon nano tubes, wherein the ratio of the concentrated sulfuric acid to the concentrated nitric acid in the mixed acid solution is 3:1, the mass concentration of the concentrated sulfuric acid is 95-98%, and the mass concentration of the concentrated nitric acid is 65-68%; Step 1.2, dissolving carboxylated carbon nanotubes in a tris buffer solution, carrying out ultrasonic oscillation for 0.5-1 h until the mixture is uniformly mixed to obtain a carbon nanotube aqueous suspension, then adding dopamine hydrochloride, carrying out mechanical stirring for full reaction, and filtering to obtain polydopamine coated carbon nanotubes; And 1.3, adding the polydopamine coated carbon nano tube into hydrochloric acid and aniline with the concentration of 0.5mol/L, performing mechanical stirring reaction to form uniform suspension, then adding ammonium persulfate solution, performing oxidative polymerization reaction under ice bath for 4-10 hours, washing the precipitate with deionized water for several times, and performing vacuum drying to obtain the polyaniline coated carbon nano tube.
5. The method for preparing the corrosion-resistant and wear-resistant epoxy coating according to claim 3, wherein the step 2 is specifically as follows: Step 2.1, preparing an ethanol water solution, wherein the volume ratio of ethanol to deionized water is 4:1; Step 2.2, respectively dispersing silicon carbide with the particle size of 5-75 mu m and chopped carbon fibers with the diameter of 7 mu m and the length of 0.1-0.5 mm in a xylene solution, and carrying out ultrasonic oscillation homogenization treatment to respectively obtain a silicon carbide solution and a chopped carbon fiber solution; And 2.3, respectively adding the solutions obtained in the step 2.2 into the solutions obtained in the step 2.1 for reaction, filtering to obtain silicon carbide and chopped carbon fibers, washing the silicon carbide and chopped carbon fibers with alcohol, and then drying in vacuum.
6. The method for preparing the corrosion-resistant and wear-resistant epoxy coating according to claim 3, wherein the step 3 is characterized by comprising the specific steps of adding the carbon nano tube, the chopped carbon fiber and the silicon carbide subjected to surface modification into a dimethylformamide solvent, carrying out ultrasonic vibration for 0.5-1 h, and then adding the epoxy resin into the solvent for mechanical stirring to uniformly disperse the carbon nano tube, the chopped carbon fiber and the silicon carbide into the epoxy resin coating.
7. The method for preparing the corrosion and wear resistant epoxy coating according to claim 4, wherein the step 4 is characterized in that a curing agent and a leveling agent are added into the epoxy resin coating prepared in the step 3, the epoxy resin coating is mechanically stirred and mixed uniformly, vacuum is pumped in a vacuum drying oven to eliminate bubbles generated by stirring, and finally the epoxy resin coating is coated on a metal substrate, and the corrosion and wear resistant epoxy coating is obtained after curing.
8. The method for preparing the corrosion-resistant and wear-resistant epoxy coating according to claim 4, wherein in the step 1, the carbon nanotubes have an outer diameter of 8-30 nm, an inner diameter of 3-10 nm and a length of 3-30 μm.
9. The method for producing a corrosion and wear resistant epoxy coating according to claim 4, wherein in step 1.2, the molar amount of the tris buffer solution is 10mM and the pH is 8.5.
10. The method for preparing the corrosion-resistant and wear-resistant epoxy coating according to claim 4, wherein in the step 2.1, the silane coupling agent is KH560, the epoxy resin in the step 3 is E44, the curing agent in the step 4 is polyamide 650, the leveling agent is BYK306, and the curing process in the step 4 is that the epoxy coating is dried at normal temperature for 12-24 hours and then dried in a vacuum oven at 80 ℃ for 4-8 hours.

Description

Corrosion-resistant wear-resistant epoxy coating and preparation method thereof Technical Field The invention belongs to the technical field of surface engineering, and particularly relates to a corrosion-resistant and wear-resistant epoxy coating and a preparation method of the corrosion-resistant and wear-resistant epoxy coating. Background The organic coating is a main protective measure of the marine equipment at present, and the epoxy resin coating is an excellent marine equipment protective coating because of excellent adhesive force, water resistance and low cost. The epoxy resin coating is formed by taking epoxy resin as a main film forming substance and adding a reinforcing phase, auxiliary fillers and auxiliary agents. The epoxy resin and reinforcing substances are various, so that the epoxy resin anticorrosive coating can be prepared into anticorrosive coatings suitable for various corrosive environments, and the epoxy resin anticorrosive coating is the most widely applied anticorrosive coating in the world at present. However, epoxy resins also have some disadvantages, such as poor strength and wear resistance, susceptibility to aging and cracking, lack of toughness, and failure to meet marine equipment requirements in their own corrosion resistance. The existing modification and preparation technology of the epoxy coating is mainly characterized in that inorganic nano fillers such as glass flakes, carbon nano tubes and graphene are added to improve the corrosion resistance of the epoxy resin, and molybdenum disulfide is added to reduce the friction coefficient of the coating or hard reinforcing phases such as aluminum oxide and tungsten carbide are added to improve the wear resistance of the coating. But most of the coating is only subjected to directional optimization and improvement on the corrosion resistance or wear resistance of the coating, and the complex and severe marine comprehensive environments such as high salt, high humidity, strong ultraviolet rays, seawater scouring, friction and the like are dealt with, so that the comprehensive requirements on corrosion resistance, wear resistance and high toughness of the epoxy resin coating are not fundamentally met. The carbon nano tube has nano scale characteristics and excellent chemical stability, and the corrosion resistance and the bonding strength of the coating can be improved by doping the carbon nano tube in the coating. The silicon carbide has extremely high hardness and stability, and can be used as a filler to improve the hardness and wear resistance of the epoxy resin coating. The chopped carbon fiber has higher strength and rigidity, is added into the resin matrix as a reinforcing body, and when external stress acts on the resin coating, the resin can transfer the stress to the carbon fiber, so that the mechanical property of the resin can be obviously improved. Disclosure of Invention The invention aims to provide a corrosion-resistant and wear-resistant epoxy coating, which solves the problems of low hardness, poor corrosion resistance and poor wear resistance of the traditional epoxy coating. Another object of the invention is to provide a method for preparing a corrosion and wear resistant epoxy coating. The first technical scheme adopted by the invention is that the corrosion-resistant and wear-resistant epoxy coating is prepared from the following raw materials, by mass, 1-5 parts of carbon nanotubes, 5-10 parts of chopped carbon fibers, 10-20 parts of silicon carbide powder, 80-150 parts of dimethylformamide solvent, 100-200 parts of epoxy resin, 100-200 parts of curing agent and 1-2 parts of leveling agent, wherein the epoxy resin is E44, the curing agent is polyamide 650, and the leveling agent is BYK306. The preparation method of the corrosion-resistant and wear-resistant epoxy coating comprises the following specific steps: Step1, surface modification of carbon nanotubes Step 1.1, preparing a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid, adding the carbon nanotubes, performing ultrasonic oscillation reaction, filtering, washing the carbon nanotubes with deionized water, and finally filtering and drying to obtain carboxylated carbon nanotubes. And 1.2, dissolving the carboxylated carbon nanotubes in a tris buffer solution, carrying out ultrasonic vibration until the carboxylated carbon nanotubes are uniformly mixed to obtain a carbon nanotube aqueous suspension, then adding dopamine hydrochloride, carrying out mechanical stirring to fully react, and filtering to obtain the polydopamine-coated carbon nanotubes. And washing the polydopamine coated carbon nano tube with deionized water for several times, and finally, fully drying in a vacuum drying oven. And 1.3, adding the polydopamine coated carbon nano tube into hydrochloric acid and aniline, and performing mechanical stirring reaction to form uniform suspension. Then, an ammonium persulfate solution was added to complete the oxidati