Connecting paint capable of improving anti-cracking performance of antifouling coating after immersion and preparation method thereof

Abstract

The present invention relates to the technical field of chemical materials, and in particular to a connecting paint and a preparation method thereof that can improve the anti-cracking performance of an antifouling coating after immersion. The connecting paint comprises the following raw materials in parts by weight: 5-15 parts of epoxy resin, 15-25 parts of acrylic resin, 5-15 parts of chloroether resin, 5-20 parts of pigment, 10-50 parts of filler, 1-3 parts of auxiliary agent and 5-15 parts of solvent. The connecting paint provided by the present invention can significantly improve the anti-cracking performance of the antifouling coating after the second docking and water loss while meeting the requirements of the traditional intermediate paint to improve the adhesion strength between the antirust coating and the antifouling coating according to the working conditions during ship repair. The intermediate paint coating for the outer plate of the ship of the present invention is applied in the field of ship construction or maintenance, can reduce the cost expenditure during the construction of the outer plate coating of the ship, significantly improve the surface state of the coating after the second discharge of the antifouling paint coating, improve the construction performance of the outer plate coating of the ship during the second discharge of the ship, reduce the construction cost expenditure, and has important practical application value.

Description

Technical Field

[0001] The invention relates to the technical field of chemical materials, and in particular to a connecting paint capable of improving the anti-cracking performance of an antifouling coating after immersion and a preparation method thereof. Background Art

[0002] Marine fouling organisms are a type of biological species that grow on man-made structures such as ships. They mainly include barnacles, oysters, mussels, seaweed and marine bacteria, which are extremely harmful to man-made structures. Taking large ocean-going ships as an example, once fouling organisms attach to them, the amount of attachment can reach 150kg / m2 within half a year, and the total amount of fouling attached to the surface of about 40,000 square meters underwater will reach 6,000 tons. The huge amount of fouling attachment not only increases the deadweight of the hull, but also changes the streamlined structure of the hull, increases the navigation resistance of the hull, and greatly increases fuel consumption. In addition, fouling organisms will cause the maneuverability of ships to deteriorate, the propeller propulsion efficiency to decrease, the noise to increase, and the sonar to be interfered with, forcing ships to enter the dock for cleaning in advance, spending huge maintenance costs, and seriously affecting the service and combat effectiveness of ships. At present, the main methods to prevent fouling organisms from attaching are mechanical removal, electrolysis of seawater and coating with antifouling coatings. Among them, coating with antifouling coatings is the most convenient and widely used method. Therefore, marine antifouling materials have become a research hotspot for domestic and foreign research institutions.

[0003] Due to the significant difference between the resin characteristics of antifouling paint products and ship antirust primer, antifouling paint cannot be directly applied on the antirust primer coating. Instead, a connecting paint product is required to complete the connection between the antirust coating and the antifouling coating, which is called connecting paint.

[0004] At present, the mainstream shipbuilding and repairing processes of major shipyards in my country all involve the situation where ships are undocking and moored at the dock for outfitting operations. The outfitting time span is relatively large, ranging from a few days to a few months, and even up to more than 6 months. After the outfitting of the ship is completed, some ships will re-enter the dock or slipway for shipbuilding and repairing operations due to various problems. During the construction process of the ship's second rafting, shipbuilding and repairing operations are carried out in the dock. The anti-fouling coating that has been applied will undergo obvious water absorption and swelling in the water environment due to the characteristics of the anti-fouling coating itself. That is, after the ship enters the dock for the second time, the surface of the coating shrinks due to water loss, and the anti-fouling coating is likely to have cracks of varying degrees. The appearance of cracks will significantly affect the overall appearance of the anti-fouling coating and will affect the progress of subsequent construction. Severe cases may even cause the coating to fall off. For specific cracking conditions of the anti-fouling paint coating after the second docking, see Figure 1 Shown

[0005] CN103965742A, published on August 6, 2014, discloses "an epoxy connecting paint for anti-rust and anti-fouling transition layer below the waterline of a ship", which has the function of improving the adhesion strength between the anti-rust coating and the anti-fouling coating. Epoxy resin and tough resin are added to the formula, and it has a certain versatility and a long recoating interval to meet the construction of anti-rust and anti-fouling coatings below the waterline of ships. However, the product of this patent only has the general function of improving the adhesion between anti-rust and anti-fouling coatings, but the cracking problem mentioned above cannot be solved.

[0006] CN 108034329A, published on May 15, 2018, discloses "an epoxy acrylic tie paint for ships and a preparation method thereof". Although the patent mentions that the tie paint has good resistance to fresh water immersion and dry-wet alternation, and the paint film surface does not crack after long-term fresh water immersion and dry-wet alternation, the anti-cracking performance of the reference refers to the fact that the tie paint itself does not crack; however, it does not solve the more important problem of cracking of the antifouling paint coating applied on the upper layer of the intermediate paint.

[0007] Therefore, a connecting paint is needed, which, on the basis of having the connecting function of conventional intermediate paint to complete the anti-rust coating and the anti-fouling coating, can improve the cracking problem of the anti-fouling paint coating after the ship is put into water for outfitting and the second docking. Summary of the invention

[0008] In order to solve the technical problems mentioned in the background technology, the present invention provides a connecting paint which can improve the anti-cracking performance of the anti-fouling coating after immersion, comprising the following raw materials in parts by weight: 5-15 parts of epoxy resin, 15-25 parts of acrylic resin, 5-15 parts of chloroether resin, 5-20 parts of pigment, 10-50 parts of filler, 1-3 parts of additive and 5-15 parts of solvent.

[0009] On the basis of the above technical solution, further, the weight ratio of the epoxy resin, acrylic resin and epichlorohydrin resin is 1:2:1.

[0010] On the basis of the above technical solution, further, the acrylic resin is an acrylic polymer, which can be a commercially available acrylic resin with a glass transition temperature of 30-40° C., a number average molecular weight of 2000-4000, and an acid value of 0-3 mg·KOH / g.

[0011] On the basis of the above technical solution, further, the epoxy resin is a bisphenol A epoxy resin with a number average molecular weight of 5000-6000 and an epoxy equivalent of 180-250 g / eq. The epoxy resin can improve the adhesion between the intermediate paint coating and the primer anti-rust coating.

[0012] On the basis of the above technical solution, further, the chloroether resin has a model of MP25 or MP35.

[0013] On the basis of the above technical solution, further, the filler includes at least one of talc powder, precipitated barium sulfate, mica powder, wollastonite powder, light calcium carbonate, kaolin, zinc oxide, quartz powder, and feldspar powder.

[0014] On the basis of the above technical solution, further, the pigment includes at least one of titanium dioxide, red iron oxide, black iron oxide, yellow iron oxide, ultramarine, carbon black, scarlet powder, toluidine red, chrome yellow, phthalocyanine blue and phthalocyanine.

[0015] On the basis of the above technical solution, further, the auxiliary agent is an anti-settling agent, and the anti-settling agent is one or two of hydrogenated castor oil, polyamide wax, organic bentonite, fumed silica, polyethylene wax, and aluminum stearate.

[0016] On the basis of the above technical scheme, further, the solvent is one or more of xylene, toluene, ethylbenzene, hexane, heptane, cyclohexane, butanol, isopropanol, ethylene glycol monomethyl ether, butyl acetate, and ethylene glycol methyl ether acetate.

[0017] A method for preparing a connecting paint as described above that can improve the anti-cracking performance of the anti-fouling coating after immersion:

[0018] Add acrylic resin, epoxy resin and chloroether acid resin into the drawing cylinder according to the proportion and disperse them evenly;

[0019] Add other pigments, fillers, additives and solvents for dispersion;

[0020] When the fineness is less than 100 μm, the viscosity is adjusted, and the material is discharged and packaged to obtain a connecting paint that can improve the anti-cracking performance of the anti-fouling coating after immersion.

[0021] The connecting paint provided by the present invention can improve the anti-cracking performance of the antifouling coating after immersion, creatively designs and uses raw materials, and by adding a chloroether resin that easily absorbs water, an acrylic resin that slightly absorbs water, and an epoxy resin that does not absorb water at all, the difference in the overall shrinkage after swelling between the intermediate paint coating and the antifouling paint coating is reduced, thereby reducing the probability of cracking of the antifouling paint coating after water absorption, swelling and water loss.

[0022] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures specifically pointed out in the description and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the cracking situation of the antifouling paint coating in the prior art after the second docking. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0025] The present invention provides the following embodiments:

[0026] Example 1

[0027] The connecting paint which can improve the anti-cracking performance of the antifouling coating after immersion: 15 parts by weight of acrylic resin, whose glass transition temperature is 33°C, number average molecular weight is 2000, and acid value is 0mg·KOH / g. 7.5 parts by weight of epoxy resin, number average molecular weight is 5000, epoxy equivalent is 180g / eq; 7.5 parts by weight of chloroether resin, model is MP25, 30 parts by weight of filler and 20 parts by weight of pigment, 1 part by weight of auxiliary agent, and 9 parts by weight of solvent;

[0028] Put the acrylic resin, epoxy resin and chloroether acid resin in the above proportion into the pulling cylinder and disperse them evenly at high speed; add other pigments, fillers, additives and solvents and disperse them at high speed; when the fineness is less than 100μm, adjust the viscosity and pack the materials.

[0029] Example 2

[0030] The connecting paint which can improve the anti-cracking performance of the antifouling coating after immersion: 20 parts by weight of acrylic resin, with a glass transition temperature of 37°C, a number average molecular weight of 3000, and an acid value of 0mg·KOH / g. 10 parts by weight of epoxy resin, with a number average molecular weight of 5000 and an epoxy equivalent of 180g / eq; 10 parts by weight of chloroether resin, model MP35, 20 parts by weight of filler and 20 parts by weight of pigment, 1 part by weight of auxiliary agent, and 9 parts by weight of solvent;

[0031] Put the acrylic resin, epoxy resin and chloroether acid resin in the above proportion into the pulling cylinder and disperse them evenly at high speed; add other pigments, fillers, additives and solvents and disperse them at high speed; when the fineness is less than 100μm, adjust the viscosity and pack the materials.

[0032] Example 3

[0033] The connecting paint which can improve the anti-cracking performance of the antifouling coating after immersion: 25 parts by weight of acrylic resin, with a glass transition temperature of 37°C, a number average molecular weight of 4000, and an acid value of 3mg·KOH / g. 12.5 parts by weight of epoxy resin, with a number average molecular weight of 5000 and an epoxy equivalent of 180g / eq; 12.5 parts by weight of chloroether resin, model MP25, 25 parts by weight of filler and 15 parts by weight of pigment, 1 part by weight of auxiliary agent, and 9 parts by weight of solvent;

[0034] Put the acrylic resin, epoxy resin and chloroether acid resin in the above proportion into the pulling cylinder and disperse them evenly at high speed; add other pigments, fillers, additives and solvents and disperse them at high speed; when the fineness is less than 100μm, adjust the viscosity and pack the materials.

[0035] In the above embodiments, the specific selection of pigment fillers, additives and solvents has little effect on the cracking performance and adhesion performance of the connecting paint. Those skilled in the art can use them specifically under the technical concept of the present invention, wherein the pigment includes body pigments such as talcum powder, precipitated barium sulfate, mica powder, wollastonite powder, light calcium carbonate, kaolin, zinc oxide, quartz powder, feldspar powder, etc.; coloring pigments such as titanium dioxide, red iron oxide, black iron oxide, yellow iron oxide, ultramarine, carbon black, red powder, toluidine red, chrome yellow, phthalocyanine blue, phthalocyanine green, etc.; the additive is an anti-settling agent, which is one or two of hydrogenated castor oil, polyamide wax, organic bentonite, fumed silica, polyethylene wax, and aluminum stearate; the solvent is one or more of xylene, toluene, ethylbenzene, hexane, heptane, cyclohexane, butanol, isopropanol, ethylene glycol monomethyl ether, butyl acetate, and ethylene glycol methyl ether acetate. The filler can be any conventional filler in the art.

[0036] The inventors found in the course of their research that during ship repair, the antifouling coating was first found to crack after absorbing water and swelling during the second docking and painting process. The main reason was that the swelling of the intermediate coating after absorbing water was quite different from the swelling degree of the antifouling paint, which led to the cracking of the antifouling paint coating. To address the above problem, the inventors designed a technical solution of adding a proportion of chloroether resin that is easy to absorb water, acrylic resin that absorbs slightly water, and epoxy resin that does not absorb water at all to the coating formula. The chloroether resin has a strong water absorption performance and can improve the water absorption of the intermediate coating. When combined with a corresponding proportion of acrylic resin and epoxy resin with strong adhesion, the deformation of the intermediate coating during the water absorption and dehydration process can be changed to be closer to that of the antifouling paint coating, and the adhesion with the primer is guaranteed on the premise of improving its tear resistance.

[0037] According to the design concept of the present invention, the following comparative examples and experimental tests are carried out:

[0038] Comparative Example 1

[0039] Using the traditional intermediate paint formula, the difference between Comparative Example 1 and Example 1 is that the remaining raw materials are the same as those of Example 1, except that no chloroether resin is added.

[0040] Comparative Example 2

[0041] A conventional intermediate paint formula is used, and chloroether resin is added. The remaining raw materials are the same as those in Example 2, except that the ratio of chloroether resin to acrylic resin is 1:1.

[0042] Comparative Example 3

[0043] A conventional intermediate paint formula is used, and chloroether resin is added. The other raw materials are the same as those in Example 1, except that the ratio of chloroether resin to epoxy resin is 2:1.

[0044] The embodiments of the present invention and the comparative examples were subjected to the following tests. The test method was to conduct a fresh water immersion resistance test on the intermediate paint antifouling paint coating system in the laboratory. After immersion for a certain period of time, the sample was taken out, dried in the shade, and the cracks on the coating surface were observed with the naked eye.

[0045] The fresh water used was ordinary tap water, the sample size was 75 mm × 150 mm, the immersion container was a 2L beaker, and 1.5L of tap water was added to each beaker; the water change cycle was weekly.

[0046] The test results are shown in Table 1:

[0047] Table 1

[0048]

[0049] Through the experimental comparison between the above embodiments and the comparative examples, it can be seen that the connecting paint provided by the present invention that can improve the anti-cracking performance of the anti-fouling coating after immersion is a technical solution in which a chloroether resin that easily absorbs water, an acrylic resin that slightly absorbs water, and an epoxy resin that does not absorb water are added to the coating formula in a certain proportion according to the actual working conditions during ship repair. While meeting the requirements of the traditional intermediate paint for improving the adhesion strength between the anti-rust coating and the anti-fouling coating, the anti-cracking performance of the anti-fouling coating after water loss during the second docking can be significantly improved.

[0050] The ship outer plate intermediate paint coating of the present invention is applied in the field of ship construction or maintenance, can reduce the cost expenditure during the construction of the ship outer plate coating, significantly improve the coating surface state after the antifouling paint coating is applied for the second time, improve the construction performance of the ship outer plate coating during the second application of the ship, reduce the construction cost expenditure, and has important practical application value.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A connecting paint capable of improving the anti-cracking performance of an antifouling coating after immersion, characterized in that: The composition is composed of the following raw materials in parts by weight: 7.5-12.5 parts of epoxy resin, 15-25 parts of acrylic resin, 7.5-12.5 parts of chloroether resin, 5-20 parts of pigment, 10-50 parts of filler, 1-3 parts of additive and 5-15 parts of solvent; The epoxy resin is bisphenol A epoxy resin; The chloroether resin has a model of MP25 or MP35; The weight ratio of the epoxy resin, acrylic resin and chloroether resin is 1:2:

1.

2. The connecting paint capable of improving the anti-cracking performance of the antifouling coating after immersion according to claim 1, characterized in that: The acrylic resin is an acrylic polymer with a glass transition temperature of 30-40° C., a number average molecular weight of 2000-4000, and an acid value of 0-3 mg·KOH / g.

3. The connecting paint capable of improving the anti-cracking performance of the antifouling coating after immersion according to claim 1, characterized in that: The epoxy resin has a number average molecular weight of 5000-6000 and an epoxy equivalent of 180-250 g / eq.

4. The connecting paint capable of improving the anti-cracking performance of the antifouling coating after immersion according to claim 1, characterized in that: The filler includes at least one of talc powder, precipitated barium sulfate, mica powder, wollastonite powder, light calcium carbonate, kaolin, zinc oxide, quartz powder, and feldspar powder.

5. The connecting paint capable of improving the anti-cracking performance of the antifouling coating after immersion according to claim 1, characterized in that: The pigment comprises at least one of titanium dioxide, red iron oxide, black iron oxide, yellow iron oxide, ultramarine, carbon black, scarlet powder, toluidine red, chrome yellow, phthalocyanine blue and phthalocyanine.

6. The connecting paint capable of improving the anti-cracking performance of the antifouling coating after immersion according to claim 1, characterized in that: The auxiliary agent is an anti-settling agent, and the anti-settling agent is one or two of hydrogenated castor oil, polyamide wax, organic bentonite, fumed silica, polyethylene wax, and aluminum stearate.

7. The connecting paint capable of improving the anti-cracking performance of the antifouling coating after immersion according to claim 1, characterized in that: The solvent is one or more of xylene, toluene, ethylbenzene, hexane, heptane, cyclohexane, butanol, isopropanol, ethylene glycol monomethyl ether, butyl acetate, and ethylene glycol methyl ether acetate.

8. A method for preparing a connecting paint capable of improving the anti-cracking performance of an antifouling coating after immersion according to any one of claims 1 to 7, characterized in that: Add acrylic resin, epoxy resin and chloroether acid resin into the drawing cylinder according to the proportion and disperse them evenly; Add other pigments, fillers, additives and solvents for dispersion; When the fineness is less than 100 μm, the viscosity is adjusted, and the material is discharged and packaged to obtain a connecting paint that can improve the anti-cracking performance of the anti-fouling coating after immersion.

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