CN-122011884-A - Self-repairing/corrosion early warning dual-functional coating based on corrosion cathode micro-area environment response release

CN122011884ACN 122011884 ACN122011884 ACN 122011884ACN-122011884-A

Abstract

The invention discloses a self-repairing/corrosion early warning dual-functional coating based on corrosion cathode micro-area environment response release, which comprises a corrosion cathode micro-area response nano container A loaded with a corrosion inhibitor A and a corrosion anode micro-area response nano container B loaded with a corrosion inhibitor B or a fluorescent agent. The preparation method of the coating comprises the steps of adding the nano container A and the nano container B into deionized water, then adding epoxy resin and a curing agent, stirring at a high speed to obtain a composite epoxy resin coating, and coating the composite epoxy resin coating on a metal substrate to obtain the self-repairing/corrosion early warning dual-functional coating after curing. The coating enables the compound corrosion inhibitor or the fluorescent agent to be accurately released under the stimulation of the environment of the corrosion cathode micro-area, and the corrosion inhibition effect of the cathode corrosion inhibitor on the corrosion cathode micro-area and the change (enhancement or quenching) of the fluorescent intensity of the fluorescent agent on the corrosion anode micro-area are utilized to indicate the corrosion area, so that the long-acting self-repairing protection and corrosion early warning effect are realized.

Inventors

XIONG LIANGLIANG
LIAO JUNXIAN
WU MENGXUE
FAN XIAOQIANG
ZHU MINHAO

Assignees

西南交通大学

Dates

Publication Date: 20260512
Application Date: 20260306

Claims (9)

1. The self-repairing/corrosion early warning dual-functional coating based on the environment response release of the corrosion cathode micro-area is characterized by comprising a corrosion cathode micro-area response nano container A loaded with a corrosion inhibitor A and a corrosion anode micro-area response nano container B loaded with a corrosion inhibitor B or a fluorescent agent; The preparation method of the nano container A comprises the following steps: S1, dissolving hexadecyl trimethyl ammonium bromide in water, regulating the pH value of the solution to be 11.5-12.5, heating to 70-90 ℃ and keeping the temperature for 20-80 min, then dropwise adding tetraethyl orthosilicate, stirring vigorously for 1-3h, cooling, centrifuging, and further cleaning to obtain an mSiO 2 nano material; S2, dispersing the mSiO 2 nano material in absolute ethyl alcohol, then adding 3- [2- (2-amino ethylamine) ethylamine ] propyl trimethoxysilane to form a mixed solution, heating the mixed solution to 100-120 ℃ for condensation reflux for 5-7 hours, and finally centrifugally separating and cleaning to obtain the f-mSiO 2 nano material; S3, dispersing the f-mSiO 2 nano material in water or ethanol solution containing the corrosion inhibitor A, placing the suspension in a vacuum environment for more than 2 hours, and centrifugally separating to obtain the f-mSiO 2 nano composite material loaded with the corrosion inhibitor, namely a nano container A; The corrosion inhibitor A is an inorganic corrosion inhibitor, and the corrosion inhibitor B is an organic corrosion inhibitor.
2. The self-repairing/corrosion early warning dual-functional coating based on corrosion cathode and anode micro-area environment response release as claimed in claim 1, wherein the preparation method of the coating is as follows: adding the nano container A and the nano container B into deionized water, then adding epoxy resin and a curing agent, stirring at a high speed to obtain a composite epoxy resin coating, and coating the composite epoxy resin coating on a metal substrate to obtain the self-repairing/corrosion early warning dual-functional coating after curing.
3. The self-repairing/corrosion early warning dual-functional coating based on corrosion cathode and anode micro-area environment response release according to claim 2, wherein the mass ratio of the nano container A to the nano container B in the coating is 1:1-4:1, and the total mass of the two nano containers is 0.3-1.0wt% of the addition amount of epoxy resin.
4. The self-repairing/corrosion early warning dual-functional coating based on corrosion cathode and anode micro-area environment response release as claimed in claim 2, wherein the preparation method of the nano container B is as follows: Adding 2-methylimidazole and a fluorescent agent into methanol to form a solution A, adding zinc nitrate hexahydrate into the other part of methanol to form a solution B, slowly adding the solution B into the solution A, stirring and reacting for 20-24 hours at room temperature, and centrifugally separating and collecting a product to obtain the nano container B.
5. The self-repairing/corrosion-warning dual-functional coating based on corrosion cathodic micro-area environmental response release of claim 4 wherein said fluorescent agent is selected from any one of 8-hydroxyquinoline, 8-hydroxyquinoline-5-sulfonic acid, rhodamine B and its derivative FD 1.
6. The self-repairing/corrosion early warning dual-functional coating based on corrosion cathode and anode micro-area environment response release according to claim 1, wherein in the step S1, the concentration of cetyl trimethyl ammonium bromide in a reaction solution is 1.5-2.5 mg/mL, and the concentration of tetraethyl orthosilicate is 0.02-0.06 mol/L.
7. The self-repairing/corrosion-warning dual-functional coating based on corrosion cathode and anode micro-area environment response release according to claim 6, wherein in the step S1, the product obtained by centrifugal separation is dispersed in a hydrochloric acid/ethanol mixed solution, and is centrifuged after stirring, so as to achieve the purpose of cleaning.
8. The self-repairing/corrosion-warning dual-functional coating based on corrosion cathode and anode micro-area environmental response release according to claim 7, wherein in step S2, the concentration of 3- [2- (2-aminoethylamine) ethylamine ] propyl trimethoxysilane in the mixed solution is 0.40-1 mol/L.
9. The self-repairing/corrosion-warning dual-functional coating based on corrosion cathode and anode micro-area environment response release according to claim 8, wherein the corrosion inhibitor A is an inorganic salt containing cerium ions.

Description

Self-repairing/corrosion early warning dual-functional coating based on corrosion cathode micro-area environment response release Technical Field The invention relates to the technical field of functional protective coatings, in particular to a self-repairing/corrosion early warning dual-functional coating based on corrosion cathode and anode micro-area environment response release. Background Organic coatings passively protect metallic materials by insulating corrosive media, the most efficient, economical, most commonly used method of corrosion protection. The addition of the corrosion inhibitor further endows the coating with active protective performance, and the corrosion inhibitor becomes one of the most widely applied methods in the corrosion prevention technology. The research on the corrosion inhibitors shows that the compounding of the corrosion inhibitors has corrosion inhibition performance far superior to that of a single corrosion inhibitor, and the compounding of organic corrosion inhibitors (2-MBT, BTA, SAL and the like), inorganic corrosion inhibitors (Ce 3+、Ce4+、La3+, sodium silicate and the like) and organic and inorganic corrosion inhibitors can show synergistic protective effects. For example, inorganic corrosion inhibitors Zn 2+ and Ce 3+/Ce4+ are used as cathode corrosion inhibitors to be deposited into a film in a corrosion cathode area, and organic corrosion inhibitors (BTA, 2-MBT and the like) are generally adsorbed into a film in a corrosion anode area, so that corrosion is cooperatively inhibited. The combination of the adsorption type anodic corrosion inhibitor and the precipitation type cathodic corrosion inhibitor shows excellent corrosion inhibition performance compared to the single corrosion inhibitor, and selective deposition of the inorganic corrosion inhibitor on the intermetallic compound and formation of the organic film of the organic corrosion inhibitor on the metal substrate are considered to be the most feasible mechanism of the synergistic effect of these compounds. The corrosion early warning means that fluorescent agent or color developing agent is used for evaluating the corrosion condition of the matrix material by utilizing interaction of fluorescent agent or color developing agent and corrosion products or fluorescence or color change phenomenon caused by change of pH value of a micro-area caused by corrosion. It has been found that the direct application of different corrosion inhibitors to the coating, or the direct application of corrosion inhibitors and fluorescent agents to the coating, has unavoidable drawbacks, such as the possibility of chemical interactions between the corrosion inhibitors and fluorescent agents and the coating and subsequent degradation and deactivation of the coating. The technical means of encapsulating the corrosion inhibitor or the fluorescent agent in the inert nano container can isolate the corrosion inhibitor component or the fluorescent agent component from the coating matrix, can achieve the purpose of controllable release and realize long-acting protection. However, the existing single nano-container can only aim at the anode (M- > M 3++ 3e,M3++ 3H2O → M(OH)3+ 3H+) or cathode (3H 2O + O2 - > 3 OH) of corrosion) The controllable release of a certain local microenvironment is realized, so that the compound corrosion inhibitor or fluorescent agent is difficult to precisely act on the corroded cathode and anode micro-areas at the same time, the corrosion inhibition efficiency is reduced, the corrosion protection life of the coating is obviously influenced, and meanwhile, the problems of poor corrosion early warning effect, insufficient sensitivity and the like exist. Disclosure of Invention Aiming at the problems of insufficient long-acting protective performance, poor corrosion early warning effect, insufficient sensitivity and the like of the traditional aqueous epoxy resin protective coating, the invention provides a self-repairing/corrosion early warning dual-functional coating based on corrosion cathode and anode micro-area environment response release. The self-repairing/corrosion early warning dual-functional coating based on the environment response release of the corrosion cathode micro-region comprises a corrosion cathode micro-region response nano container A loaded with a corrosion inhibitor A and a corrosion anode micro-region response nano container B loaded with a corrosion inhibitor B or a fluorescent agent. The preparation method of the coating comprises the following steps: adding the nano container A and the nano container B into deionized water, then adding epoxy resin and a curing agent, stirring at a high speed to obtain a composite epoxy resin coating, and coating the composite epoxy resin coating on a metal substrate to obtain the self-repairing/corrosion early warning dual-functional coating after curing. The preparation method of the nano container A comprises the following steps: S1, dissolving cety