Water-based fluororesin modified epoxy passivation paint

Abstract

The invention discloses a water-based fluororesin modified epoxy passivation paint and a preparation method thereof, and the paint comprises the following components by weight: 15-30% of a water-based polyvinylidene fluoride emulsion, 30-50% of a water-based epoxy resin emulsion, 3-6% of a metal corrosion inhibitor, 1-2% of a coalescing agent, 3-7% of a penetrant, 0.2-0.5% of a thickener, 6-10% of a passivator, and the balance of deionized water. Water-based polyvinylidene fluoride resin is used for modifying water-based epoxy resin to serve as a main film forming matter, a passivating agent is used for curing original rust of a steel base layer, a non-rust surface is passivated, a metal corrosion inhibitor permeates into the surface of the base material to be dissolved with trivalent and tetravalent iron ions on the surface, and a stable chelate layer is generated. The acid and alkali corrosion resistance is higher, and especially the chloride ion resistance is more prominent; and when a steel structure facade spraying process is adopted, the film-forming property is better, and the problem that uniform passivation of a steel facade and uniform film forming of a paint film are difficult to guarantee by adopting conventional water-based paint can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of passivation paints, in particular to water-based fluororesin modified epoxy passivation paints. Background Art

[0002] As the country pays more and more attention to safety and environmental protection, the safety issue of anti-corrosion surface treatment of steel structures in Class A areas in industrial enterprises, especially chemical industries, is a difficult problem to solve. With the improvement of safety requirements, the traditional sandblasting or manual rust removal process can no longer meet the safety requirements and the actual conditions of on-site working conditions. Although there are conventional water-based rust-free coatings on the market, they have poor chloride ion resistance, uneven rust conversion on steel structures, serious spray sag, poor uniform reaction and curing film formation on the surface of the steel base, and a single film-forming resin with average performance, which ultimately leads to unsatisfactory rust removal effect on the steel base and a short secondary maintenance cycle. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the above technical defects, provide a water-based fluororesin modified epoxy passivating paint and a preparation method, break through the problems of incomplete grinding and rust removal, incomplete rust removal, and insufficient film thickness of facade spraying in traditional steel structure maintenance, and can complete rust removal, metal passivation, shielding, and decoration operations in one construction. The material penetration function of metal corrosion inhibitors and passivators is utilized to better penetrate the passivator into the rust layer to solidify the rust. The corrosion inhibitor and chloride ions combine to slow down the corrosion of the corrosive medium to the steel, thereby achieving a more thorough rust conversion purpose. Compared with traditional rust conversion liquids, the viscosity of the present invention is higher, and the paint film can be uniformly converted after spraying the steel facade, and the film thickness can achieve the purpose of better protecting the steel base layer.

[0004] In order to solve the above problems, the technical solution of the present invention is: a water-based fluororesin modified epoxy passivation paint, comprising the following components in parts by weight: 15-30% of water-based polyvinylidene fluoride emulsion, 30-50% of water-based epoxy resin emulsion, 3-6% of metal corrosion inhibitor, 1-2% of film-forming aid, 3-7% of penetrant, 0.2-0.5% of thickener, 3-5% of gallic acid, 3-5% of salicylic acid or citric acid and the balance of deionized water.

[0005] Furthermore: the emulsion is a water-based epoxy emulsion and a water-based polyvinylidene fluoride emulsion, wherein the water-based epoxy emulsion is 30-50% and the polyvinylidene fluoride emulsion is 15-30%.

[0006] Further: the film-forming aid is ethylene glycol butyl ether or propylene glycol methyl ether.

[0007] Further: the penetrant is isopropyl alcohol.

[0008] Furthermore: the thickener is sodium carboxymethyl cellulose.

[0009] Further: the metal corrosion inhibitor is one or more of hydroxyethylidene diphosphonic acid or hydroxyethylidene diphosphonate.

[0010] Furthermore: the passivating agent is composed of 3-5% gallic acid and 3-5% salicylic acid or citric acid, wherein the ratio of gallic acid to salicylic acid or citric acid is 1:1.

[0011] The preparation method of water-based fluororesin modified epoxy passivation paint comprises the following preparation steps:

[0012] Step 1, preparing slurry 1, first pouring the deionized water into a reaction kettle, then pouring the thickener and film-forming aid into a stirring kettle in sequence, stirring and mixing evenly to form slurry 1;

[0013] Step 2, adding the gallic acid, salicylic acid or citric acid into a deionized water reactor at a certain temperature, stirring and dissolving them evenly, then sequentially adding water-based polyvinylidene fluoride emulsion, water-based epoxy resin emulsion, the metal corrosion inhibitor and the penetrant and stirring them evenly, then adding the slurry prepared in step 1 and stirring them evenly, thus forming the water-based fluororesin modified epoxy passivation paint;

[0014] Further: in step 1, 15-30% deionized water is first poured into the reaction kettle, 0.2-0.5% of the thickener sodium carboxymethyl cellulose is added, and the dispersion mixer is started, at 300-400rpm, the stirring time is 10-20min, the materials are stirred evenly, and then 1-2% of the film-forming aid ethylene glycol butyl ether or propylene glycol methyl ether is added, and the stirring is continued to be evenly obtained to obtain slurry 1;

[0015] Further: in step 2, first pour 10-15% deionized water into the reaction kettle, heat to 70±10°C, add 3-5% gallic acid and 3-5% salicylic acid or citric acid, stir and dissolve evenly at 800-1000rpm, add 30-50% water-based epoxy resin emulsion, 15-30% water-based polyvinylidene fluoride emulsion, 3-8% hydroxyethylidene diphosphonic acid or hydroxyethylidene diphosphonate and 3-7% isopropanol in sequence, continue to add and stir evenly at 300-400rpm, then add all the slurry and continue to stir evenly to obtain the water-based fluororesin modified epoxy passivation paint.

[0016] Further: firstly make slurry one according to the process of claim 9, and then add slurry one according to the process sequence of claim 10, so as to obtain a water-based fluororesin modified epoxy passivating paint with moderate viscosity suitable for facade spraying.

[0017] The advantages of the present invention compared with the prior art are:

[0018] The present invention can make the coating have longer weather resistance, better adhesion and corrosion resistance, better vertical spray film-forming property, and the function of combining with chloride ions, by adding water-based polyvinylidene fluoride emulsion, water-based epoxy resin emulsion and hydroxyethylidene diphosphonic acid or hydroxyethylidene diphosphonate, so as to greatly extend the passivation of rust layer and the corrosion inhibition of unrusted steel base surface. DETAILED DESCRIPTION

[0019] It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to directions, and the words "inside" and "outside" refer to directions toward or away from the geometric center of a specific component, respectively.

[0020] In order to make the contents of the present invention more clearly understood, the technical solutions in the embodiments of the present invention are described clearly and completely.

[0021] Example 1

[0022] The water-based fluororesin modified epoxy passivating paint is prepared from the following raw materials, counted by weight: 15 parts of water-based polyvinylidene fluoride emulsion, 45 parts of water-based epoxy resin emulsion, 3 parts of hydroxyethylidene diphosphonic acid, 1 part of ethylene glycol butyl ether, 5 parts of isopropanol, 0.2 parts of sodium carboxymethyl cellulose, 3 parts of gallic acid, 3 parts of salicylic acid, and 25-30 parts of deionized water.

[0023] The preparation method of water-based fluororesin modified epoxy passivation paint is as follows:

[0024] (1) first pour 10-15 parts of deionized water into a reaction kettle, add 0.2 parts of the thickener sodium carboxymethyl cellulose, and start a dispersing mixer at 300-400 rpm for 10-20 minutes to evenly stir the materials, then add 1 part of a film-forming aid ethylene glycol butyl ether, continue to stir evenly, and obtain a slurry for standby use;

[0025] (2) Pour 10-15 parts of deionized water into a reaction kettle, heat to 70±10°C, add 3 parts of gallic acid and 3 parts of salicylic acid, and stir at 800-1000 rpm for 10 minutes to dissolve evenly, then add 45 parts of water-based epoxy resin emulsion, 15 parts of water-based polyvinylidene fluoride emulsion, 3 parts of hydroxyethylidene diphosphonic acid and 5 parts of isopropanol in sequence, continue to add at 300-400 rpm for 20-30 minutes and stir evenly, then add all the slurry and continue to stir for 10-20 minutes to obtain a water-based fluororesin modified epoxy passivation paint.

[0026] Example 2

[0027] The water-based fluororesin modified epoxy passivating paint is prepared from the following raw materials, counted by weight: 20 parts of water-based polyvinylidene fluoride emulsion, 35 parts of water-based epoxy resin emulsion, 4 parts of hydroxyethylidene diphosphonate, 1.5 parts of ethylene glycol butyl ether, 4 parts of isopropanol, 0.3 parts of sodium carboxymethyl cellulose, 4 parts of gallic acid, 4 parts of citric acid, and 25-30 parts of deionized water.

[0028] The preparation method of water-based fluororesin modified epoxy passivation paint is as follows:

[0029] (1) first pour 10-15 parts of deionized water into a reaction kettle, add 0.3 parts of sodium carboxymethyl cellulose, and start a dispersing mixer at 300-400 rpm for 10-20 min to evenly stir the materials, then add 1.5 parts of ethylene glycol butyl ether, continue to stir evenly, and obtain a slurry for standby use;

[0030] (2) Pour 10-15 parts of deionized water into a reaction kettle, heat to 70±10°C, add 4 parts of gallic acid and 4 parts of salicylic acid, and stir at 800-1000 rpm for 10 minutes to dissolve evenly, then add 35 parts of water-based epoxy resin emulsion, 20 parts of water-based polyvinylidene fluoride emulsion, 4 parts of hydroxyethylidene diphosphonate and 4 parts of isopropanol in sequence, continue to add at 300-400 rpm for 20-30 minutes and stir evenly, then add all the slurry and continue to stir for 10-20 minutes to obtain a water-based fluororesin modified epoxy passivation paint.

[0031] Example 3

[0032] The water-based fluororesin modified epoxy passivating paint is prepared from the following raw materials, counted by weight: 28 parts of water-based polyvinylidene fluoride emulsion, 30 parts of water-based epoxy resin emulsion, 5 parts of hydroxyethylidene diphosphonate, 1.2 parts of ethylene glycol butyl ether, 6 parts of isopropanol, 0.25 parts of sodium carboxymethyl cellulose, 5 parts of gallic acid, 5 parts of citric acid, and 25-30 parts of deionized water.

[0033] The preparation method of water-based fluororesin modified epoxy passivation paint is as follows:

[0034] (1) first pour 10-15 parts of deionized water into a reaction kettle, add 0.25 parts of sodium carboxymethyl cellulose, and start a dispersing mixer at 300-400 rpm for 10-20 min to evenly stir the materials, then add 1.2 parts of ethylene glycol butyl ether, continue to stir evenly, and obtain a slurry for standby use;

[0035] (2) Pour 10-15 parts of deionized water into a reaction kettle, heat to 70±10°C, add 5 parts of gallic acid and 5 parts of citric acid, and stir at 800-1000 rpm for 10 minutes to dissolve evenly, then add 30 parts of water-based epoxy resin emulsion, 28 parts of water-based polyvinylidene fluoride emulsion, 5 parts of hydroxyethylidene diphosphonate and 6 parts of isopropanol in sequence, continue to add at 300-400 rpm for 20-30 minutes and stir evenly, then add all the slurry and continue to stir for 10-20 minutes to obtain a water-based fluororesin modified epoxy passivation paint.

[0036] Example 4

[0037] The water-based fluororesin modified epoxy passivation paint is prepared from the following raw materials, counted by weight: 18 parts of water-based polyvinylidene fluoride emulsion, 35 parts of water-based epoxy resin emulsion, 3 parts of hydroxyethylidene diphosphonic acid, 1.3 parts of ethylene glycol butyl ether, 4.5 parts of isopropanol, 0.35 parts of sodium carboxymethyl cellulose, 6 parts of gallic acid, 6 parts of salicylic acid, and 25-30 parts of deionized water.

[0038] The preparation method of water-based fluororesin modified epoxy passivation paint is as follows:

[0039] (1) first pour 10-15 parts of deionized water into a reaction kettle, add 0.35 parts of sodium carboxymethyl cellulose, and start a dispersing mixer at 300-400 rpm for 10-20 min to evenly stir the materials, then add 1.3 parts of ethylene glycol butyl ether, continue to stir evenly, and obtain a slurry for standby use;

[0040] (2) Pour 10-15 parts of deionized water into a reaction kettle, heat to 70±10°C, add 6 parts of gallic acid and 6 parts of salicylic acid, and stir at 800-1000 rpm for 10 minutes to dissolve evenly, then add 35 parts of water-based epoxy resin emulsion, 18 parts of water-based polyvinylidene fluoride emulsion, 3 parts of hydroxyethylidene diphosphonate and 4.5 parts of isopropanol in sequence, continue to add at 300-400 rpm for 20-30 minutes and stir evenly, then add all the slurry and continue to stir for 10-20 minutes to obtain a water-based fluororesin modified epoxy passivation paint.

[0041] Example 5

[0042] The water-based fluororesin modified epoxy passivating paint is prepared from the following raw materials, counted by weight: 25 parts of water-based polyvinylidene fluoride emulsion, 40 parts of water-based epoxy resin emulsion, 4 parts of hydroxyethylidene diphosphonate, 1.6 parts of ethylene glycol butyl ether, 4.8 parts of isopropanol, 0.4 parts of sodium carboxymethyl cellulose, 3.5 parts of gallic acid, 3.5 parts of citric acid, and 25-30 parts of deionized water.

[0043] The preparation method of water-based fluororesin modified epoxy passivation paint is as follows:

[0044] (1) first pour 10-15 parts of deionized water into a reaction kettle, add 0.4 parts of sodium carboxymethyl cellulose, and start a dispersing mixer at 300-400 rpm for 10-20 min to evenly stir the materials, then add 1.6 parts of ethylene glycol butyl ether, continue to stir evenly, and obtain a slurry for standby use;

[0045] (2) Pour 10-15 parts of deionized water into a reaction kettle, heat to 70±10°C, add 3.5 parts of gallic acid and 3.5 parts of salicylic acid, and stir at 800-1000 rpm for 10 minutes to dissolve evenly. Then, add 40 parts of water-based epoxy resin emulsion, 25 parts of water-based polyvinylidene fluoride emulsion, 4 parts of hydroxyethylidene diphosphonate and 4.8 parts of isopropanol in sequence, and continue to add at 300-400 rpm for 20-30 minutes to stir evenly. Then, add all the slurry and continue to stir for 10-20 minutes to obtain a water-based fluororesin modified epoxy passivation paint.

[0046] By adding water-based polyvinylidene fluoride emulsion, hydroxyethylidene diphosphonic acid and sodium carboxymethyl cellulose to the water-based epoxy resin emulsion, the coating can have longer weather resistance, water resistance and corrosion resistance, especially more outstanding chloride ion resistance. It also has better film-forming properties when sprayed on the facade and reduces the sag of the paint film, providing a more effective construction solution for secondary steel repairs.

[0047] The present invention and its implementation methods are described above, and such description is not restrictive, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design methods and embodiments similar to the technical solution without creativity, which should all fall within the protection scope of the present invention.

Claims

1. Water-based fluororesin modified epoxy passivation paint, characterized by: The invention comprises the following components in parts by weight: 15-30% of aqueous polyvinylidene fluoride emulsion, 30-50% of aqueous epoxy resin emulsion, 3-6% of metal corrosion inhibitor, 1-2% of film-forming aid, 3-7% of penetrant, 0.2-0.5% of thickener, 3-5% of gallic acid, 3-5% of salicylic acid or citric acid and the balance of deionized water.

2. The water-based fluororesin modified epoxy passivation paint according to claim 1, characterized in that: The emulsion is water-based epoxy emulsion and water-based polyvinylidene fluoride emulsion, wherein the water-based epoxy emulsion is 30-50% and the polyvinylidene fluoride emulsion is 15-30%.

3. The water-based fluororesin modified epoxy passivation paint according to claim 1, characterized in that: The film-forming aid is ethylene glycol butyl ether or propylene glycol methyl ether.

4. The water-based fluororesin modified epoxy passivation paint according to claim 1, characterized in that: The penetrant is isopropyl alcohol.

5. The water-based fluororesin modified epoxy passivation paint according to claim 1, characterized in that: The thickener is sodium carboxymethyl cellulose.

6. The water-based fluororesin modified epoxy passivation paint according to claim 1, characterized in that: The metal corrosion inhibitor is one or more of hydroxyethylidene diphosphonic acid or hydroxyethylidene diphosphonate.

7. The water-based fluororesin modified epoxy passivation paint according to claim 1, characterized in that: The passivating agent is composed of 3-5% gallic acid and 3-5% salicylic acid or citric acid, wherein the ratio of gallic acid to salicylic acid or citric acid is 1:

1.

8. The method for preparing the water-based fluororesin modified epoxy passivation paint according to any one of claims 2 to 7, characterized in that: The method comprises the following preparation steps: Step 1, preparing slurry 1, first pouring the deionized water into a reaction kettle, then pouring the thickener and film-forming aid into a stirring kettle in sequence, stirring and mixing evenly to form slurry 1; Step 2: Add the gallic acid, salicylic acid or citric acid into a deionized water reactor at a certain temperature, stir and dissolve them evenly, then add the water-based polyvinylidene fluoride emulsion, the water-based epoxy resin emulsion, the metal corrosion inhibitor and the penetrant in turn and stir them evenly, then add the slurry prepared in step 1 and stir them evenly to form the water-based fluororesin modified epoxy passivation paint.

9. The method for preparing the water-based fluororesin modified epoxy passivation paint according to claim 8, characterized in that: In step one, 15-30% deionized water is poured into a reaction kettle, 0.2-0.5% of the thickener sodium carboxymethyl cellulose is added, and a dispersing mixer is started at 300-400 rpm for 10-20 minutes to evenly stir the materials, and then 1-2% of a film-forming aid ethylene glycol butyl ether or propylene glycol methyl ether is added, and the stirring is continued to evenly obtain slurry one.

10. The method for preparing the water-based fluororesin modified epoxy passivation paint according to claim 8, characterized in that: In step 2, first pour 10-15% deionized water into a reaction kettle, heat it to 70±10°C, add 3-5% gallic acid and 3-5% salicylic acid or citric acid, stir and dissolve evenly at 800-1000rpm, add 30-50% water-based epoxy resin emulsion, 15-30% water-based polyvinylidene fluoride emulsion, 3-8% hydroxyethylidene diphosphonic acid or hydroxyethylidene diphosphonate and 3-7% isopropanol in sequence, continue to add and stir evenly at 300-400rpm, then add all the slurry and continue to stir evenly to obtain the water-based fluororesin modified epoxy passivation paint.

11. The method for preparing the water-based fluororesin modified epoxy passivation paint according to claim 9 or 10, characterized in that: Firstly, slurry one is made according to the process of claim 9, and then slurry one is added according to the process sequence of claim 10, so as to obtain a water-based fluororesin modified epoxy passivating paint with moderate viscosity suitable for facade spraying.