A temperature-resistant anticorrosive coating for pipelines and a preparation method thereof

Abstract

The application discloses a kind of pipeline temperature-resistant anticorrosive paint and preparation method thereof, first mixed epoxy resin, additive and mixed solvent are mixed uniformly according to proportion, then titanium dioxide, talcum powder and precipitated barium sulfate are added, and uniformly dispersed, then heat-resistant filler is added and stirred uniformly, to obtain component A;Again, modified hyperbranched amino silicone curing agent and mixed solvent are mixed uniformly according to proportion, to obtain component B;Finally, component A and component B are mixed uniformly to obtain the pipeline temperature-resistant anticorrosive paint.The prepared paint of the application is high solid content, environmentally friendly, can be used for CUI insulation layer pipeline, has excellent temperature resistance and corrosion resistance, and can also be used for outdoor pipeline, has excellent weather resistance and durability.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of anticorrosive coatings, and particularly relates to a temperature-resistant anticorrosive coating for pipelines and a preparation method thereof. BACKGROUND

[0002] In the field of petrochemical industry, pipelines are essential transportation tools, and these pipelines are generally made of metal materials. During use, corrosion occurs to the pipelines, especially the surface of the temperature-bearing pipeline, the high temperature of which can damage the coating, and the high temperature can also intensify the corrosion of the pipeline by the corrosion medium. Moreover, most of the temperature-bearing pipelines are coated with thermal insulation materials, which leads to the accumulation of moisture and corrosive medium in the annular gap between the thermal insulation material and the metal surface and the defects on the metal surface, and thus the corrosion is intensified. In addition, the thermal insulation material itself has water permeability, and the corrosion pollutants (chloride, silicate, etc.) in the material and the outside environment can be dissolved with the entry of water, and the ions accelerate the corrosion rate, leading to the corrosion under the thermal insulation layer. Therefore, the use of temperature-resistant anticorrosive coatings for pipeline protection is one of the most economical and effective means.

[0003] The phenolic epoxy thermal insulation anticorrosive coating used under the thermal insulation layer has excellent adhesion and corrosion resistance, and is suitable for protective coating on thermal insulation pipelines. It has a wide application in the fields of petrochemical industry, offshore platforms, etc. However, the current epoxy thermal insulation coating for pipelines has certain defects in use, specifically as follows: (1) it can only be applied to pipelines below 200 DEG C, and the temperature resistance range needs to be further improved; (2) the phenolic epoxy coating has poor resistance to thermal shock, and the alternating cold and heat can easily cause the adhesion of the coating to decrease and the protective performance to deteriorate; (3) the weather resistance is poor, and the coating applied to the outdoor pipeline is prone to aging and cracking. Therefore, it is necessary to develop a pipeline temperature-resistant anticorrosive coating with high solid content and environmental protection, which can be used for CUI thermal insulation pipeline under the thermal insulation layer and has excellent temperature resistance and corrosion resistance, and can also be used for outdoor pipeline and has excellent weather resistance and durability. SUMMARY

[0004] The present application is proposed to solve the problems in the prior art, and aims to provide a temperature-resistant anticorrosive coating for pipelines and a preparation method thereof.

[0005] The present application is realized by the following technical scheme:

[0006] A temperature-resistant anticorrosive coating for pipelines, wherein the anticorrosive coating comprises component A and component B, and the mass ratio of the component A to the component B is (3-4):1.

[0007] The component A comprises the following components and the mass fraction of each component is as follows:

[0008]

[0009]

[0010] The sum of the weight parts of each component of the A component is 100 parts;

[0011] The components and the mass parts of each component included in the B component are as follows:

[0012] Modified hyperbranched aminosilicone curing agent 90-98 parts;

[0013] Mixed solvent 2-10 parts;

[0014] The sum of the weight parts of each component of the B component is 100 parts.

[0015] In the above technical solution, the mixed epoxy resin is a mixture of phenolic epoxy resin and bisphenol F epoxy resin; the mass ratio of the phenolic epoxy resin and the bisphenol F epoxy resin is (1-2):1; the phenolic epoxy resin is a phenolic epoxy resin with an epoxy value of 0.55-0.60; and the bisphenol F epoxy resin is a bisphenol F epoxy resin with an epoxy value of 0.55-0.65.

[0016] In the above technical solution, the titanium white is rutile titanium white; the particle size of the talcum powder is 400-500 mesh; the heat-resistant filler is basalt flake; and the particle size of the basalt flake is 300-500 mesh.

[0017] In the above technical solution, the auxiliary agent is any one or several of a dispersing agent, a defoaming agent or a rheological auxiliary agent.

[0018] In the above technical solution, the dispersing agent is BYK-ATU; the defoaming agent is BYK-066 or AFCONA-2722; and the rheological auxiliary agent is organic bentonite.

[0019] In the above technical solution, the mixed solvent is a mixture of dimethylbenzene, butanol and propylene glycol methyl ether, and the mass ratio of the dimethylbenzene, butanol and propylene glycol methyl ether is (60-70):(10-20):(20-25).

[0020] In the above technical solution, the modified hyperbranched aminosilicone curing agent is obtained by reacting aminosiloxane, dipropylene glycol and anhydrous barium hydroxide.

[0021] In the above technical solution, the aminosiloxane is N-(2-aminoethyl)-3-aminopropyl methoxysilane and / or 3-aminopropyl triethoxysilane.

[0022] In the technical scheme, the preparation method of the modified hyperbranched amino silicone curing agent is as follows: the amino siloxane, dipropylene glycol and anhydrous barium hydroxide are uniformly mixed in a mass ratio of (50-55):(45-50):(0.5-1), nitrogen protection is performed, reaction is carried out at 80 DEG C for 0.3 h, then the temperature is increased to 100 DEG C and reaction is carried out for 3 h, the anhydrous barium hydroxide is removed, and the hyperbranched amino silicone curing agent is prepared.

[0023] A preparation method of a temperature-resistant anticorrosive coating for pipelines, comprising the following steps:

[0024] (I) mixing epoxy resin, additives and mixed solvents in proportion, adding into a reaction kettle and uniformly mixing, then adding titanium dioxide, talc and precipitated barium sulfate, uniformly dispersing and grinding to a fineness of 40 microns or less, then adding heat-resistant fillers, stirring for 30-50 minutes to uniformity, to obtain component A;

[0025] (II) adding modified hyperbranched amino silicone curing agent and mixed solvents into the reaction kettle in proportion, stirring for 20 minutes to uniformity, to obtain component B;

[0026] (III) mixing component A and component B uniformly to obtain the temperature-resistant anticorrosive coating for pipelines.

[0027] The present application has the following beneficial effects:

[0028] The present application provides a temperature-resistant anticorrosive coating for pipelines and a preparation method thereof, the prepared coating is high in solid content and environmentally friendly, can be used for pipelines under CUI thermal insulation layer and has excellent temperature resistance and corrosion resistance, and can be used for outdoor pipelines and has excellent weather resistance and durability. DETAILED DESCRIPTION

[0029] In order to enable the personnel in the technical field to better understand the technical scheme of the present application, the technical scheme of the present application is further described below in combination with the description and through specific embodiments.

[0030] Example 1

[0031] A temperature-resistant anticorrosive coating for pipelines, wherein component A is made of the following components in mass fraction:

[0032] 25 parts of mixed epoxy resin (the mass ratio of phenolic epoxy resin and bisphenol F epoxy resin is 1:1);

[0033] 10 parts of titanium dioxide

[0034] 10 parts of talc;

[0035] 25 parts of precipitated barium sulfate;

[0036] 15 parts of basalt flake

[0037] 3 parts of dispersant BYK-ATU

[0038] 1 part of defoaming agent BYK-066

[0039] 1 part of organic bentonite

[0040] 10 parts of mixed solvent (xylene, butanol, propylene glycol methyl ether mass ratio 7:1:2);

[0041] The B component has the following components in parts by weight:

[0042] 98 parts of modified hyperbranched amino silicone curing agent

[0043] 2 parts of mixed solvent (xylene, butanol, propylene glycol methyl ether mass ratio 7:1:2).

[0044] The modified hyperbranched amino silicone curing agent is prepared by a preparation method comprising the following steps: mixing N-(2-aminoethyl)-3-aminopropyl methoxysilane, dipropylene glycol, anhydrous barium hydroxide, keeping 80℃ for 0.3h, then increasing the temperature to 100℃ for 3h, removing anhydrous barium hydroxide, to obtain a hyperbranched amino silicone curing agent, and the mass ratio of N-(2-aminoethyl)-3-aminopropyl methoxysilane, dipropylene glycol, anhydrous barium hydroxide is 55:45:0.5.

[0045] The preparation method of the above-mentioned pipeline temperature-resistant anticorrosive paint comprises the following steps:

[0046] (I) Mix the mixed epoxy resin, dispersant, defoaming agent, organic bentonite, and solvent in a reaction kettle, uniformly disperse the titanium dioxide, talc, and precipitated barium sulfate, then grind to a fineness of less than 40μm, add basalt flakes and stir for 30min to obtain the A component;

[0047] (II) Add the modified hyperbranched amino silicone curing agent and mixed solvent to the reaction kettle, stir for 20min to obtain the B component;

[0048] (III) Mix the A component and the B component uniformly to obtain the pipeline temperature-resistant anticorrosive paint.

[0049] Example 2

[0050] A pipeline temperature-resistant anticorrosive paint, the A component is made of the following components in parts by mass:

[0051] 25 parts of mixed epoxy resin (mass ratio of phenolic epoxy resin and bisphenol F epoxy resin is 2:1);

[0052] 15 parts of titanium dioxide

[0053] 20 parts of talc;

[0054] 15 parts of precipitated barium sulfate;

[0055] 14 parts of basalt flake

[0056] 3 parts of dispersant BYK-ATU

[0057] 8 parts of mixed solvent (xylene, butanol, propylene glycol methyl ether mass ratio 6:2:2);

[0058] The B component is composed of the following components in parts by weight:

[0059] 95 parts of modified hyperbranched amino silicone curing agent

[0060] 5 parts of mixed solvent (xylene, butanol, propylene glycol methyl ether mass ratio 6:2:2).

[0061] The modified hyperbranched amino silicone curing agent is prepared by a preparation method comprising the following steps: mixing 3-aminopropyl triethoxysilane, dipropylene glycol, anhydrous barium hydroxide, keeping the temperature at 80°C for 0.3h, then increasing the temperature to 100°C for 3h, removing the anhydrous barium hydroxide, and obtaining the hyperbranched amino silicone curing agent, wherein the mass ratio of 3-aminopropyl triethoxysilane, dipropylene glycol, and anhydrous barium hydroxide is 45:55:1.

[0062] The preparation method of the above-mentioned pipeline temperature-resistant anticorrosive coating comprises the following steps:

[0063] (1) Mix the mixed epoxy resin, dispersant, and mixed solvent in a reaction kettle, uniformly disperse the titanium dioxide and talc powder, and then grind to a fineness of less than 40μm, then add the basalt flake and stir for 50min to obtain the A component;

[0064] (2) Add the modified hyperbranched amino silicone curing agent and mixed solvent to the reaction kettle, stir for 20min to obtain the B component;

[0065] (3) Mix the A component and the B component uniformly to obtain the pipeline temperature-resistant anticorrosive coating.

[0066] Example 3

[0067] A pipeline temperature-resistant anticorrosive coating, wherein the A component is prepared from the following components in parts by mass:

[0068] 15 parts of mixed epoxy resin (the mass ratio of phenolic epoxy resin and bisphenol F epoxy resin is 2:1);

[0069] 15 parts of titanium dioxide

[0070] 20 parts of talc powder;

[0071] 25 parts of precipitated barium sulfate;

[0072] 5 parts of basalt flake;

[0073] 3 parts of dispersant BYK-ATU;

[0074] 1 part of defoaming agent AFCONA-2722;

[0075] 1 part of organic bentonite;

[0076] 15 parts of mixed solvent (xylene, butanol, propylene glycol methyl ether mass ratio 6:1.5:2.5);

[0077] The B component is composed of the following components in parts by weight:

[0078] 90 parts of modified hyperbranched amino silicone curing agent

[0079] 10 parts of mixed solvent (xylene, butanol, propylene glycol methyl ether mass ratio 6:1.5:2.5).

[0080] The modified hyperbranched amino silicone curing agent is prepared by a preparation method comprising the following steps: uniformly mixing N-(2-aminoethyl)-3-aminopropyl methoxysilane, dipropylene glycol, anhydrous barium hydroxide, keeping 80℃ for 0.3h under nitrogen protection, then heating to 100℃ for 3h, removing anhydrous barium hydroxide, to obtain a hyperbranched amino silicone curing agent, and the mass ratio of N-(2-aminoethyl)-3-aminopropyl methoxysilane, dipropylene glycol, anhydrous barium hydroxide is 50:45:1.

[0081] The preparation method of the above-mentioned pipeline temperature-resistant anticorrosive paint comprises the following steps:

[0082] (1) Mix the mixed epoxy resin, dispersant, defoaming agent, organic bentonite, mixed solvent in the reaction kettle, uniformly disperse the titanium dioxide, talc, precipitated barium sulfate, and then grind to a fineness of less than 40μm, then add the basalt flake and stir for 40min to obtain the A component;

[0083] (2) Put the modified hyperbranched amino silicone curing agent and mixed solvent into the reaction kettle, stir for 20min to obtain the B component;

[0084] (3) Mix the A component and B component uniformly to obtain the pipeline temperature-resistant anticorrosive paint.

[0085] The prepared pipeline high-temperature resistant anticorrosive coating in Examples 1-3 was tested for adhesion, temperature change resistance, temperature cycle resistance, salt mist resistance and aging resistance. The test selected a steel plate of 150 mm x 75 mm x 3 mm, and the paint film thickness was about 250 μm. The adhesion of the coating was tested according to GB / T 5210-2006 pull-off method; the heat cycle resistance of the coating was tested according to GB / T 1735-2009 and GB / T 1766-2008, which provided that the temperature was raised to 300℃, the temperature was kept for 6 hours, and the oven was naturally cooled to room temperature for 1 cycle; the temperature change resistance of the coating was tested according to JG / T 25-2017, which provided that the temperature was raised to 300℃, the temperature was kept for 2 hours, the water was cooled to 0℃, and the temperature was kept for 1 cycle; the neutral salt mist test was performed according to ASTM B117; and the UV aging resistance test was performed according to GB / T 1865-2009. The commercial phenolic epoxy paint MC-NE-4 on the market was selected as a comparative example, and the test results of Examples 1-3 and the comparative example are shown in Table 1.

[0086] Table 1: Paint film performance test results

[0087]

[0088] As can be seen from Table 1, the pipeline high-temperature resistant anticorrosive coating prepared in Examples 1-3, which uses a mixture of bisphenol F epoxy resin and phenolic epoxy resin as the main film-forming material, can reduce the brittle and hard phenomenon of the paint film caused by the high functionality and rigidity of the phenolic epoxy resin, and improve the flexibility of the paint film. At the same time, the amino group is connected to the silicone resin through a silicon-carbon bond, which catalyzes the condensation of siloxane to form hyperbranched branches. Most of the reactive sites in the hyperbranched structure are located in the branch structure, which reduces the internal stress of the epoxy system and further improves the toughness. Therefore, the heat cycle resistance and temperature change resistance of Examples 1-3 are better than those of the comparative example. Due to the introduction of the hyperbranched structure, there are many reactive sites, the coating is more dense, the crosslinking density is greater, and the corrosion resistance is greatly improved. At the same time, the basalt flakes can be distributed in parallel in the coating, which prolongs the time for the corrosion medium to reach the substrate, fills the pores in the resin coating, and enhances the shielding property of the coating. Therefore, the adhesion and salt mist resistance of Examples 1-3 are significantly better than those of the comparative example. The introduction of the modified hyperbranched amino silicone as a curing agent introduces stable Si-O bonds, which can resist ultraviolet radiation and oxidation corrosion, maintain stable weather resistance and durability, and enable Examples 1-3 to have excellent UV aging resistance. In addition, the pipeline high-temperature resistant anticorrosive coating of the present application is a high solid content coating, which can be applied at a high film thickness, and is green and environmentally friendly.

[0089] Principle of the present application:

[0090] The application selects a mixture of bisphenol F epoxy resin and phenolic epoxy resin as a main film forming material, and the main effects are as follows: (1) the bisphenol F epoxy resin has excellent thermal stability and good corrosion resistance, and the viscosity is relatively small, so that the solid content of the temperature-resistant and corrosion-resistant paint can be improved, the solvent consumption of the whole paint is reduced, and the green environmental protection is realized; (2) the bisphenol F epoxy resin and the phenolic epoxy resin are mixed and used, so that the brittle and hard phenomenon of the paint film caused by the high functionality and rigidity of the phenolic epoxy resin can be reduced, the flexibility of the paint film is improved, and the temperature change resistance of the coating is enhanced.

[0091] The application selects a modified hyperbranched amino silicone curing agent, and the main benefits are as follows: after being mixed with the epoxy resin, the amino group is connected with the silicone resin through a silicon-carbon bond, which not only catalyzes the condensation of siloxane to form a hyperbranched branch, but also serves as a curing reaction group at room temperature. The hyperbranched branch has many active sites and high functionality, so that the coating is more dense, has excellent corrosion resistance and fast drying time; most of the reactive sites in the hyperbranched structure are located in the branch structure, which reduces the internal stress of the epoxy system and plays a toughening effect; the Si-O bond formed by the covalent bond in the modified hyperbranched amino silicone has sufficient stability, can resist ultraviolet radiation and oxidation corrosion, so that the coating can remain stable in outdoor environment for a long time, and the weather resistance of the coating is improved.

[0092] In the resin system built in the application, the modified hyperbranched amino silicone is used as a curing agent, and the beneficial effects are unexpected. First, the viscosity of the mixed epoxy resin is effectively low, and the prepared temperature-resistant and corrosion-resistant paint is a green high-solid-content paint. Second, because the mixed epoxy resin has excellent corrosion resistance and flexibility, the introduced silicone forms a siloxane condensation structure in the epoxy system, enhances the bond energy of the resin molecules in the coating, and the temperature resistance of the coating exceeds 300 DEG C of the traditional phenolic epoxy paint. Third, the presence of the silane bond greatly enhances the stability of the coating, and the outdoor pipeline has excellent weather resistance and durability.

[0093] The application selects basalt flake as a temperature-resistant filler, and the basalt flake is a green and environmentally friendly sheet material with high thermal stability. In the paint film, the basalt flake can be distributed in the coating in parallel, prolongs the time for the corrosion medium to reach the substrate, fills the pores in the resin coating, enhances the shielding property of the coating, effectively improves the corrosion resistance of the coating, and the sheet structure is dispersed in the coating, which can effectively reduce the curing internal stress under high film thickness and improve the anti-cracking property in the cold and hot impact process.

[0094] The applicant declares that the above description is only a specific embodiment of the application, but the protection scope of the application is not limited thereto. It should be understood by those skilled in the art that any changes or replacements within the technical scope disclosed by the application can be easily thought out by any person skilled in the art, and all fall within the protection scope and disclosure scope of the application.

Claims

1. A temperature resistant anticorrosive coating for pipes, characterized by: The anticorrosive paint comprises an A component and a B component, and the mass ratio of the A component and the B component is (3-4):1; The A component comprises the following components and the mass fraction of each component is as follows: Mixed epoxy resin 15-25 parts; Titanium white powder 10-15 parts; Talc powder 10-20 parts; Precipitated barium sulfate 15-25 parts; Heat-resistant filler 5-15 parts; Auxiliary agent 3-5 parts; Mixed solvent 8-15 parts; The sum of the weight fraction of each component of the A component is 100 parts; The B component comprises the following components and the mass fraction of each component is as follows: Modified hyperbranched amino silicone curing agent 90-98 parts; Mixed solvent 2-10 parts; The sum of the weight fraction of each component of the B component is 100 parts; The mixed epoxy resin is a mixture of phenolic epoxy resin and bisphenol F epoxy resin, and the mass ratio of the phenolic epoxy resin and the bisphenol F epoxy resin is (1-2):1; the phenolic epoxy resin is phenolic epoxy resin with an epoxy value of 0.55-0.60; and the bisphenol F epoxy resin is bisphenol F epoxy resin with an epoxy value of 0.55-0.65; The modified hyperbranched amino silicone curing agent is obtained by the reaction of aminosiloxane, dipropylene glycol and anhydrous barium hydroxide.

2. The temperature resistant anticorrosive coating for pipes according to claim 1, characterized in that: The titanium white powder is rutile titanium white powder; the particle size of the talc powder is 400-500 mesh; the heat-resistant filler is basalt flake; and the particle size of the basalt flake is 300-500 mesh.

3. The temperature resistant anticorrosive coating for pipes according to claim 1, characterized in that: The auxiliary agent is any one or several of dispersant, defoaming agent or rheological auxiliary agent.

4. The temperature resistant anticorrosive coating for pipes according to claim 3, characterized in that: The dispersant is BYK-ATU; the defoaming agent is BYK-066 or AFCONA-2722; and the rheological auxiliary agent is organic bentonite.

5. The temperature resistant anticorrosive coating for pipes according to claim 1, characterized in that: The mixed solvent is a mixture of dimethylbenzene, butanol and propylene glycol methyl ether, and the mass ratio of the dimethylbenzene, butanol and propylene glycol methyl ether is (60-70):(10-20):(20-25).

6. The temperature resistant anticorrosive coating for pipes according to claim 1, characterized in that: The aminosiloxane is N-(2-aminoethyl)-3-aminopropyl methoxysilane and / or 3-aminopropyl triethoxysilane.

7. The temperature resistant anticorrosive coating for pipes according to claim 1, characterized in that: The preparation method of the modified hyperbranched amino silicone curing agent is as follows: aminosiloxane, dipropylene glycol and anhydrous barium hydroxide are uniformly mixed in a mass ratio of (50-55):(45-50):(0.5-1), and then the mixture is kept at 80°C for 0.3h under nitrogen protection, and then the temperature is increased to 100°C for 3h, and then the anhydrous barium hydroxide is removed to obtain the hyperbranched amino silicone curing agent.

8. A process for the production of a temperature-resistant anticorrosive coating material for pipes according to one of claims 1 to 7, characterized in that: The method comprises the following steps: (I) uniformly mixing the mixed epoxy resin, auxiliary agent and mixed solvent according to the proportion, then adding titanium white powder, talc powder and precipitated barium sulfate into the mixture and uniformly dispersing, then adding heat-resistant filler and uniformly stirring to obtain the A component; (II) uniformly mixing the modified hyperbranched amino silicone curing agent and mixed solvent according to the proportion to obtain the B component; (III) uniformly mixing the A component and the B component to obtain the pipeline heat-resistant anticorrosive paint.

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