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CN-121379300-B - Epoxy zinc-rich primer containing modified graphene and preparation method thereof

CN121379300BCN 121379300 BCN121379300 BCN 121379300BCN-121379300-B

Abstract

The invention discloses an epoxy zinc-rich primer containing modified graphene and a preparation method thereof, and belongs to the technical field of anti-corrosion paint, wherein the surface of graphene oxide is carboxylated, magnesium and cerium ions are used for compound modification to obtain modified graphene oxide, phenyl Janus-SiO 2 particles are synthesized and benzotriazol corrosion inhibitor is loaded to obtain corrosion inhibition type Janus compound particles, xylene, epoxy resin, zinc powder, a dispersing agent, a defoaming agent, heavy calcium and mica powder are stirred step by step to obtain a component A, an epoxy curing agent, xylene, carboxylated compound powder, corrosion inhibition type Janus compound particles and a dispersing agent are prepared into a component B by ultrasonic waves, and A, B components are mixed uniformly to obtain the epoxy zinc-rich primer containing modified graphene; the comprehensive performance breakthrough of the primer in the aspects of adhesive force, long-acting corrosion resistance and cathode stripping resistance is realized.

Inventors

  • JIANG XIAOLIN
  • DI CHENGMIN

Assignees

  • 安徽江锐新材料股份有限公司

Dates

Publication Date
20260512
Application Date
20251210

Claims (9)

  1. 1. The preparation method of the epoxy zinc-rich primer containing the modified graphene is characterized by comprising the following steps of: Grafting carboxyl on the surface of graphene oxide, adding carboxylated graphene oxide powder into a 0.2mol/L magnesium nitrate solution, performing ultrasonic treatment for 60-80min, continuously stirring, and performing ultrasonic treatment for 15-30min by using the ultrasonic function of a cell crusher to obtain a mixed dispersion liquid; Adding cerium nitrate hexahydrate into the dispersion, stirring for 10-20min, transferring into a three-neck flask, magnetically stirring, heating to 90-100 ℃ under the protection of nitrogen, refluxing for 1-2h, carrying out suction filtration, washing a filter cake with deionized water until the filtrate is neutral, carrying out vacuum drying to constant weight, grinding, and sieving with a 200-mesh sieve to obtain modified graphene oxide composite powder; Synthesizing phenyl Janus-SiO 2 particles by an emulsion interface method, and loading a benzotriazole corrosion inhibitor to obtain corrosion inhibition Janus composite particles; Step three, the component A is obtained by stirring xylene, epoxy resin, zinc powder, a dispersing agent, a defoaming agent, heavy calcium and mica powder step by step, the component B is prepared by ultrasonic treatment of an epoxy curing agent, xylene, modified graphene oxide composite powder, corrosion inhibition Janus composite particles and the dispersing agent, and A, B components are uniformly mixed to obtain the epoxy zinc-rich primer containing modified graphene.
  2. 2. The method for preparing the modified graphene-containing epoxy zinc-rich primer according to claim 1, wherein the dosage ratio of carboxylated graphene oxide powder to 0.2mol/L magnesium nitrate solution is 1g to 1L; The dosage ratio of the dispersion liquid and cerium nitrate hexahydrate is 500-800mL:43.4-50.2g.
  3. 3. The preparation method of the modified graphene-containing epoxy zinc-rich primer according to claim 1, wherein the specific preparation steps of the carboxylated graphene oxide powder are as follows: adding graphene oxide powder into deionized water, performing ultrasonic treatment for 1-2h, transferring into ice water bath, slowly adding sodium hydroxide and chloroacetic acid under continuous magnetic stirring, performing ultrasonic treatment for 2-3h, centrifugally washing with 1mol/L dilute hydrochloric acid until filtrate is neutral, and performing freeze drying to constant weight to obtain carboxylated graphene oxide powder.
  4. 4. The method for preparing the modified graphene-containing epoxy zinc-rich primer according to claim 3, wherein the dosage ratio of the graphene oxide powder to deionized water to sodium hydroxide to chloroacetic acid is 1-3 g/1-3L/50-80 g/10-15 g.
  5. 5. The preparation method of the modified graphene-containing epoxy zinc-rich primer according to claim 1, wherein the specific preparation steps of the phenyl Janus-SiO 2 particles are as follows: Dissolving hexadecyl trimethyl ammonium bromide in deionized water, and dropwise adding ammonia water to adjust the pH value of the solution to 10 to obtain a water phase, and uniformly mixing tetraethoxysilane, 3-aminopropyl trimethoxy silane, phenyl trimethoxy silane and toluene to obtain an oil phase; Mixing the water phase and the oil phase, shearing and emulsifying for 5-10min at 10000-12000rpm by using a high-speed shearing emulsifying machine, transferring into a three-neck flask, reacting for 12-15h at a stirring rate of 450-600rpm under a water bath condition of 70-80 ℃, filtering, washing the product with absolute ethyl alcohol and deionized water for 3 times in sequence, freeze-drying to constant weight, and grinding to obtain phenyl Janus-SiO 2 particles with an average particle size of 5 mu m; the dosage ratio of the cetyl trimethyl ammonium bromide to the deionized water is 1-3g:200-500mL; the mass ratio of the tetraethoxysilane to the 3-aminopropyl trimethoxysilane to the phenyl trimethoxysilane to the toluene is 4-6:1.6-2.2:0.8-1.2:80-100; the volume ratio of the water phase to the oil phase is 200-500:98.5-124.6.
  6. 6. The preparation method of the modified graphene-containing epoxy zinc-rich primer as claimed in claim 1, wherein the specific preparation steps of the corrosion inhibition type Janus composite particles are as follows: Adding phenyl Janus-SiO 2 particles into absolute ethyl alcohol, stirring for 20-30min, adding benzotriazole, stirring uniformly, transferring to a three-neck flask, reacting for 8-10h at a stirring rate of 300-500rpm under the water bath condition of 25-30 ℃, washing for 5-8 times by using absolute ethyl alcohol, freeze-drying for 24-36h, and grinding to obtain corrosion inhibition Janus composite particles; the dosage ratio of the phenyl Janus-SiO 2 particles, the absolute ethyl alcohol and the benzotriazole is 2-5g:60-100mL:2-5g.
  7. 7. The preparation method of the modified graphene-containing epoxy zinc-rich primer according to claim 1, wherein the specific preparation steps of the modified graphene-containing epoxy zinc-rich primer are as follows: Adding the dimethylbenzene and the epoxy resin into a beaker, uniformly stirring at a low speed, adding zinc powder, stirring for 10-20min at 750-850rpm, adding the dispersing agent, the defoamer, the heavy calcium and the mica powder, stirring for 15-25min at 2000-3000rpm, and vacuum drying to constant weight for later use; and the component B is prepared by mixing an epoxy curing agent, dimethylbenzene, modified graphene oxide composite powder, corrosion inhibition Janus composite particles and a dispersing agent, uniformly dispersing by ultrasonic, and adding the component A into the component B, and uniformly stirring at 750-800rpm to obtain the epoxy zinc-rich primer containing modified graphene.
  8. 8. The preparation method of the modified graphene-containing epoxy zinc-rich primer is characterized in that the mass ratio of xylene to epoxy resin to zinc powder to dispersant to defoamer to heavy calcium to mica powder is 5-8:8.5-9.8:60-70:0.5-0.8:0.5-0.8:8-10:8-10; The mass ratio of the epoxy curing agent to the dimethylbenzene to the modified graphene oxide composite powder to the corrosion inhibition Janus composite particles to the dispersing agent is 4.5-6.5:4-6:0.3-0.5:0.2-0.3:0.1-0.2; The mass ratio of the component A to the component B is 85.5-101.4:9.1-13.5.
  9. 9. An epoxy zinc-rich primer containing modified graphene, which is prepared by the preparation method of the epoxy zinc-rich primer containing modified graphene according to any one of claims 1-8.

Description

Epoxy zinc-rich primer containing modified graphene and preparation method thereof Technical Field The invention belongs to the technical field of anti-corrosion paint, and particularly relates to an epoxy zinc-rich primer containing modified graphene and a preparation method thereof. Background The epoxy zinc-rich primer is a core material in the field of industrial metal corrosion prevention, is prepared by taking epoxy resin as a film forming base material, taking 60% -80% high-proportion zinc powder as an anti-rust core, and matching with additives such as a polyamide curing agent, a toughening agent, a diluent and the like, and is used for constructing a long-acting corrosion-resistant barrier for metal base materials such as steel and the like through a double mechanism of physical shielding and sacrificial anode cathode protection, thereby being a base layer of a scene corrosion-resistant system such as a bridge, ocean engineering, chemical equipment, a steel structure and the like. Because zinc salt rust returning and paint film foaming are easy to occur due to zinc oxidation acceleration caused by chloride ions in high humidity/salt-containing environments (ocean and chemical plants), curing is incomplete due to reaction inhibition and moisture mixing in low-temperature high-humidity construction, paint film falling off is easy to be caused by combination resistance after substrate treatment is not up to standard, interlayer stripping is easy to be caused by acid-base reaction due to improper finishing paint matching, and along with upgrading of extreme environment corrosion resistance requirements, industry tries to add graphene to strengthen physical shielding, optimize electrochemical protection, improve mechanical performance and prolong service life, but direct addition is easy to cause agglomeration and hydrophobic inertia due to Van der Waals force, compatibility is poor, high specific surface area absorbs curing agent interference reaction, and the contradiction between high cost and difficult process adaptation exists. The Chinese patent application with publication number of CN111777918A discloses a graphene film for improving the salt spray resistance of an epoxy zinc-rich primer, preparation and application, and uses the compatibility difference between graphene and an epoxy resin matrix to realize highly oriented arrangement of the graphene in a coating so as to form a conductive bridge with zinc powder, and uses a lamellar structure of the conductive bridge to generate a maze effect, so that a diffusion path of a corrosive medium is prolonged, the cathodic protection effect of the zinc powder is enhanced, and finally, the salt spray resistance of a paint film is obviously improved. In order to avoid damaging the graphene structure, a physical blending and directional arrangement mode is adopted, but even orientation of graphene is difficult to ensure in practical construction, unmodified graphene is still easy to agglomerate in resin, continuity of a conductive network is affected, and a synergistic corrosion prevention system formed by graphene and zinc powder is almost ineffective. Disclosure of Invention The invention aims to provide an epoxy zinc-rich primer containing modified graphene and a preparation method thereof, wherein the epoxy zinc-rich primer is prepared by carboxylating modified graphene oxide, then obtaining a synergistic barrier and corrosion inhibition function through magnesium ion intercalation and cerium compound modification, and then preparing a benzotriazol corrosion inhibitor loaded by phenyl Janus-SiO 2 particles, so that the comprehensive performance breakthrough of the primer in the aspects of adhesive force, long-acting corrosion resistance and cathode stripping resistance is realized cooperatively. The aim of the invention can be achieved by the following technical scheme: the preparation method of the epoxy zinc-rich primer containing the modified graphene comprises the following steps: Grafting carboxyl on the surface of graphene oxide, and carrying out composite modification on the graphene oxide by magnesium and cerium ions by a hydrothermal method to obtain modified graphene oxide. And secondly, synthesizing phenyl Janus-SiO 2 particles by an emulsion interface method, and loading a benzotriazole corrosion inhibitor to obtain corrosion inhibition type Janus composite particles. Step three, the component A is obtained by stirring xylene, epoxy resin, zinc powder, a dispersing agent, a defoaming agent, heavy calcium and mica powder step by step, the component B is prepared by ultrasonic processing of an epoxy curing agent, xylene, carboxylated composite powder, corrosion inhibition Janus composite particles and the dispersing agent, and the components A, B are uniformly mixed to obtain the epoxy zinc-rich primer containing modified graphene. Further, the preparation method of the modified graphene oxide specifically comprises the following steps: add