A special chemical resistant coating and a method for preparing the same

Abstract

The application discloses a kind of special chemical resistant coating and preparation method thereof, the coating includes: A component and B component;A component includes: organic-inorganic hybrid resin, active diluent, dispersing agent, defoaming agent, leveling agent, rheological aid, first inert flaky filler, second inert flaky filler and optional pigment;B component includes: high-functionality aliphatic amine, low viscosity modified alicyclic amine and triethylene tetramine.The special chemical resistant coating of the application has excellent chemical resistance, especially acid and alkali resistance, and is solvent-free, green, environmentally friendly and safe.

Description

Technical Field

[0001] This invention belongs to the field of chemical-resistant coating technology, and more specifically, relates to a special chemical-resistant coating and its preparation method. Background Technology

[0002] Chemical-resistant coatings are coatings applied to substrates such as steel and concrete that come into direct contact with chemicals such as acids, alkalis, solvents, and solutions, providing chemical resistance and protection. Application scenarios include the inner walls of equipment and facilities such as storage tanks, pipelines, and pools in fields such as petroleum refining, fine chemicals, new energy, and wastewater treatment.

[0003] Currently, the technologies used in chemical-resistant coatings are generally epoxy phenolic resins and vinyl esters. Epoxy phenolic resin products can generally only withstand low concentrations of acids, alkalis, alcohols, aliphatic hydrocarbons, and some aromatic hydrocarbons. However, their resistance to high concentrations of acids and alkalis, strong oxidizing acids, high-temperature alkalis, and strongly polar solvents is limited. Furthermore, epoxy phenolic resins usually require baking or post-curing to achieve good chemical resistance. Vinyl esters are particularly outstanding in acid and alkali resistance, especially acid resistance, and are often used in high-temperature, humid, corrosive gases (such as in flue gas desulfurization units). However, vinyl ester products generally have lower resistance to alkalis and solvents, and their formulations contain reactive styrene and use peroxides as curing agents, both of which are explosive and flammable, posing significant safety hazards during coating application. Moreover, vinyl ester technology is based on free radical polymerization, which is highly temperature-dependent, with rapid reactions and gelation, causing many inconveniences in coating application. On-site application requires adjusting the mixing ratio according to the environment, and extra care must be taken before the gelation time. Summary of the Invention

[0004] The purpose of this invention is to provide a special chemical-resistant coating and its preparation method. The special chemical-resistant coating of this invention has excellent chemical resistance, especially acid and alkali resistance, and does not contain solvents, making it green, environmentally friendly and safe.

[0005] To achieve the above objectives, one aspect of the present invention provides a special chemical-resistant coating, the coating comprising: component A and component B;

[0006] Component A includes: an organic-inorganic hybrid resin, an active diluent, a dispersant, an antifoaming agent, a leveling agent, a rheology modifier, a first inert flake filler, a second inert flake filler, and optional pigments;

[0007] Component B comprises: high-functionality aliphatic amines, low-viscosity modified alicyclic amines, and triethylenetetramine.

[0008] According to the present invention, preferably, by weight parts, component A comprises: 35-50 parts of organic-inorganic hybrid resin, 2-4 parts of reactive diluent, 0.2-0.6 parts of dispersant, 0.1-0.3 parts of defoamer, 0.2-0.6 parts of leveling agent, 0.5-1 parts of rheology modifier, 5-15 parts of first inert flake filler, 5-15 parts of second inert flake filler, and 0-6 parts of pigment;

[0009] By mass fraction, component B comprises: 3-5 parts of high-functionality aliphatic amine, 5-10 parts of low-viscosity modified alicyclic amine, and 8-12 parts of triethylenetetramine.

[0010] According to the present invention, preferably, the organic-inorganic hybrid resin is an organosilicon-modified epoxy resin.

[0011] In this invention, an organic-inorganic hybrid resin is used. On the one hand, from the perspective of film formation, cross-linking, and curing, the high-functionality resin gives the cured and cross-linked paint film excellent chemical resistance. On the other hand, the combination of organic and inorganic materials allows the excellent corrosion resistance, temperature resistance, and wear resistance of inorganic materials to be simultaneously reflected with the good toughness and workability of organic materials, further improving the product's chemical resistance, mechanical properties, and workability.

[0012] According to the present invention, preferably, the active diluent is plant polyene phenol glycidyl ether;

[0013] The dispersant is a polydiol polyester-modified polyolefin imide;

[0014] The defoamer is a polyolefin polymer-based non-silicone defoamer;

[0015] The leveling agent is a polymethylalkylsiloxane solution;

[0016] The rheology modifier is organically modified bentonite.

[0017] In this invention, the organically modified bentonite is preferably BENTONE SD-2 from ELEMENTIS or HT-S307 from HIDIS.

[0018] According to the present invention, preferably, the first inert sheet filler is glass flakes;

[0019] The second inert sheet-like filler is sericite.

[0020] In this invention, two types of inert flake fillers are combined, glass flakes and sericite, to enhance the chemical resistance and impermeability barrier of the coating film.

[0021] According to the present invention, preferably, the pigment comprises titanium dioxide and iron black; the mass ratio of titanium dioxide to iron black is (3-10):1.

[0022] According to the present invention, preferably, the high-functionality fatty amine is an aliphatic polyamine polymer, and the functionality of the high-functionality fatty amine is 3-5;

[0023] Preferably, the high-functionality fatty amine is Evonik's Ancamine 2422.

[0024] According to the present invention, preferably, the viscosity of the low-viscosity modified alicyclic amine at 25°C is 300-500 cp;

[0025] Preferably, the low-viscosity modified alicyclic amine is Evonik's Ancamine 2280.

[0026] In this invention, component B is a compound of a high-functionality aliphatic amine, a low-viscosity modified alicyclic amine, and triethylenetetramine. The high-functionality aliphatic amine provides excellent chemical resistance, can be cured at room temperature, and offers good usability. The low-viscosity modified alicyclic amine, in addition to providing excellent chemical resistance, exhibits good low-temperature curing performance and is resistant to water stains and oil. The triethylenetetramine, thanks to its chemical activity and crosslinking ability, forms a highly crosslinked three-dimensional network structure that not only enhances the coating's chemical resistance but also significantly improves its mechanical strength (such as hardness and abrasion resistance) while aiding in low-temperature curing.

[0027] According to the present invention, preferably, the mass ratio of A to B is (3-5):1.

[0028] Another aspect of the present invention provides a method for preparing the above-mentioned coating, the method comprising:

[0029] The organic-inorganic hybrid resin, reactive diluent, dispersant, defoamer, leveling agent, rheology modifier, first inert flake filler, second inert flake filler, and optional pigment are mixed evenly to obtain component A.

[0030] The high-functionality aliphatic amine, the low-viscosity modified alicyclic amine, and the triethylenetetramine are mixed evenly to obtain component B.

[0031] The technical solution of the present invention has the following beneficial effects:

[0032] (1) The special chemical-resistant coating of the present invention can withstand high concentrations of acids and alkalis, such as 98% sulfuric acid, 37% hydrochloric acid, 50% sodium hydroxide, etc., and can also withstand small molecule high polarity solvents, such as dichloromethane, acetonitrile and tetrahydrofuran.

[0033] (2) The special chemical-resistant coating of the present invention can exhibit good chemical resistance without baking or post-curing.

[0034] (3) The special chemical-resistant coating of the present invention is solvent-free, green, environmentally friendly and safe.

[0035] (4) The special chemical-resistant coating of the present invention can be applied by brushing, rolling, or spraying. The application requirements are the same as those of solvent-free epoxy phenolic coatings.

[0036] Other features and advantages of the present invention will be described in detail in the following detailed description section. Detailed Implementation

[0037] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0038] The present invention is further illustrated by the following examples:

[0039] In the following embodiments and comparative examples:

[0040] The organic-inorganic hybrid resin is an organosilicon-modified epoxy resin, purchased from Aikeli New Materials Co., Ltd., with the brand name TY-S02;

[0041] The active diluent was plant polyene glycidyl ether, purchased from Changshu Naisu Biotechnology, brand name PLR602A;

[0042] The dispersant is a polydiol polyester modified polyolefin imide, specifically BYK Chemical's DISPERBYK-2155;

[0043] The defoamer is a polyolefin polymer-based non-silicone defoamer, specifically BYK-1790 from BYK Chemicals.

[0044] The leveling agent is a polymethylalkylsiloxane solution, specifically BYK-077 from BYK Chemicals.

[0045] The rheology modifier is organically modified bentonite, specifically BENTONE SD-2 from ELEMENTIS.

[0046] The glass flakes were purchased from Norchem Chemicals, brand name NCF-015;

[0047] The sericite was purchased from Chuzhou Gerui Mining Co., Ltd., and its grade was GA-2.

[0048] The titanium dioxide was purchased from Sichuan Longmang Titanium Industry, and its grade is R-996.

[0049] The iron black was purchased from Shanghai Yipin Pigment, and its brand name is Ultrafine Iron Oxide Black S330M.

[0050] The high-functionality fatty amine is an aliphatic polyamine polymer with a functionality of 4, purchased from Evonik, and its brand name is Ancamine 2422.

[0051] The low-viscosity alicyclic amine has a viscosity of 450 cp at 25°C. It was purchased from Evonik Industries, and its brand name is Ancamine 2280.

[0052] Triethylenetetramine was purchased from Evonik Industries under the brand name Ancamine TETA.

[0053] Example 1

[0054] This embodiment provides a special chemical-resistant coating, which includes: component A and component B;

[0055] By weight, component A comprises: 50 parts organic-inorganic hybrid resin, 3 parts PLR602A (reactive diluent), 0.5 parts DISPERBYK-2155 (dispersant), 0.3 parts BYK-1790 (defoamer), 0.6 parts BYK-077 (leveling agent), 0.8 parts BENTONE SD-2 (rheology modifier), 10 parts glass flakes (NCF-015), 10 parts sericite (GA-2), 4 parts titanium dioxide (R-996), and 0.8 parts iron black (S330M).

[0056] By mass, component B comprises: 5 parts of Ancamine 2422 (high-functionality aliphatic amine), 5 parts of Ancamine 2280 (low-viscosity alicyclic amine), and 10 parts of Ancamine TETA (triethylenetetramine).

[0057] The specific preparation method is as follows:

[0058] The organic-inorganic hybrid resin, reactive diluent, dispersant, defoamer, leveling agent, rheology modifier, glass flakes, sericite, titanium dioxide and iron black are mixed evenly to obtain component A;

[0059] The high-functionality aliphatic amine, the low-viscosity alicyclic amine and the triethylenetetramine were mixed evenly to obtain component B.

[0060] Mix components A and B at a mass ratio of 4:1, apply the mixture at 25°C, and cure it at 25°C for 7 days.

[0061] Example 2

[0062] This embodiment provides a special chemical-resistant coating, which includes: component A and component B;

[0063] By weight, component A comprises: 40 parts organic-inorganic hybrid resin, 3 parts PLR602A (reactive diluent), 0.5 parts DISPERBYK-2155 (dispersant), 0.3 parts BYK-1790 (defoamer), 0.6 parts BYK-077 (leveling agent), 0.8 parts BENTONE SD-2 (rheology modifier), 15 parts glass flakes (NCF-015), 15 parts sericite (GA-2), 4 parts titanium dioxide (R-996), and 0.8 parts iron black (S330M).

[0064] By mass, component B comprises: 5 parts of Ancamine 2422 (high-functionality aliphatic amine), 5 parts of Ancamine 2280 (low-viscosity alicyclic amine), and 10 parts of Ancamine TETA (triethylenetetramine).

[0065] The preparation method in this embodiment is the same as in Embodiment 1.

[0066] Mix components A and B at a mass ratio of 4:1, apply the mixture at 25°C, and cure it at 25°C for 7 days.

[0067] Example 3

[0068] This embodiment provides a special chemical-resistant coating, which includes: component A and component B;

[0069] By weight, component A comprises: 44.5 parts organic-inorganic hybrid resin, 4 parts PLR602A (reactive diluent), 0.6 parts DISPERBYK-2155 (dispersant), 0.2 parts BYK-1790 (defoamer), 0.4 parts BYK-077 (leveling agent), 0.5 parts BENTONE SD-2 (rheology modifier), 10 parts glass flakes (NCF-015), 10 parts sericite (GA-2), 4 parts titanium dioxide (R-996), and 0.8 parts iron black (S330M).

[0070] By mass, component B comprises: 3 parts of Ancamine 2422 (high-functionality aliphatic amine), 10 parts of Ancamine 2280 (low-viscosity alicyclic amine), and 12 parts of Ancamine TETA (triethylenetetramine).

[0071] The preparation method in this embodiment is the same as in Embodiment 1.

[0072] Mix components A and B at a mass ratio of 3:1, apply the mixture at 25°C, and cure it at 25°C for 7 days.

[0073] Comparative Example 1

[0074] This comparative example improves a chemical-resistant coating, which comprises: component A and component B;

[0075] The only difference between component A and Example 1 is that the organic-inorganic hybrid resin is replaced with Dow DEN 425 low-viscosity phenolic epoxy resin.

[0076] The B component is the same as in Example 1.

[0077] The specific preparation method is as follows:

[0078] The Dow DEN 425 low-viscosity phenolic epoxy resin, reactive diluent, dispersant, defoamer, leveling agent, rheology modifier, glass flakes, sericite, titanium dioxide and iron black are mixed evenly to obtain component A.

[0079] The high-functionality aliphatic amine, the low-viscosity alicyclic amine and the triethylenetetramine were mixed evenly to obtain component B.

[0080] Mix components A and B at a mass ratio of 4:1, apply the mixture at 25°C, and cure it at 25°C for 7 days.

[0081] Comparative Example 2

[0082] This comparative example improves a chemical-resistant coating, which comprises: component A and component B;

[0083] Component A is the same as in Example 1;

[0084] Component B is Ancamine TETA (triethylenetetramine);

[0085] The specific preparation method is as follows:

[0086] The organic-inorganic hybrid resin, reactive diluent, dispersant, defoamer, leveling agent, rheology modifier, glass flakes, sericite, titanium dioxide and iron black are mixed evenly to obtain component A;

[0087] Triethylenetetramine was used as component B.

[0088] Mix components A and B at a mass ratio of 4:1, apply the mixture at 25°C, and cure it at 25°C for 7 days.

[0089] Test case

[0090] The coating films of the above embodiments and comparative examples were tested after curing at 25°C for 7 days (except for the first item in Table 1). The specific test method refers to HGT 5572-2019 Acid-resistant and anti-corrosion coatings for the inner walls of petrochemical equipment; the specific test results are shown in Table 1. Among them, the first item in Table 1 is the time for mixing components A and B according to the mixing ratio of the above embodiments and comparative examples, applying at 5°C, and allowing to fully dry and cure at 5°C.

[0091] Table 1

[0092]

[0093]

[0094] Table 1 shows that: Example 1, by using a composite curing agent, balanced adhesion, chemical resistance, and mechanical properties. Example 2, by adding a high content of filler, significantly improved chemical resistance and hardness, but slightly reduced impact toughness. Example 3, with its low viscosity system, was easier to apply, achieving fast drying and maintaining acid and alkali resistance, while slightly decreasing adhesion and solvent resistance. Comparative Example 1 used conventional phenolic epoxy resin, resulting in a significant decrease in the coating's chemical resistance and mechanical properties. Comparative Example 2, due to the use of a single curing agent, also experienced a significant decrease in the coating's chemical resistance and mechanical properties.

[0095] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A special chemical-resistant coating, characterized in that, The coating comprises: Component A and Component B; By weight, component A comprises: 35-50 parts of organic-inorganic hybrid resin, 2-4 parts of reactive diluent, 0.2-0.6 parts of dispersant, 0.1-0.3 parts of defoamer, 0.2-0.6 parts of leveling agent, 0.5-1 parts of rheology modifier, 5-15 parts of first inert flake filler, 5-15 parts of second inert flake filler, and 0-6 parts of pigment; By mass fraction, component B comprises 3-5 parts of a high-functionality aliphatic amine, 5-10 parts of a low-viscosity modified alicyclic amine, and 8-12 parts of triethylenetetramine; wherein the high-functionality aliphatic amine is an aliphatic polyamine polymer with a functionality of 3-5, and is Evonik's Ancamine 2422; the low-viscosity modified alicyclic amine has a viscosity of 300-500 cp at 25°C, and is Evonik's Ancamine 2280; The organic-inorganic hybrid resin is an organosilicon-modified epoxy resin with the brand name TY-S02. The active diluent is plant polyene phenol glycidyl ether; The dispersant is a polydiol polyester-modified polyolefin imide; The defoamer is a polyolefin polymer-based non-silicone defoamer; The leveling agent is a polymethylalkylsiloxane solution; The rheology modifier is organically modified bentonite; The first inert sheet-like filler is glass flakes; The second inert sheet-like filler is sericite; The mass ratio of A to B is (3-5):1; The special chemical-resistant coating is resistant to 98% sulfuric acid, 37% hydrochloric acid, 50% sodium hydroxide, as well as dichloromethane, acetonitrile, and tetrahydrofuran.

2. The coating according to claim 1, characterized in that, The pigments include titanium dioxide and iron black; the mass ratio of titanium dioxide to iron black is (3-10):

1.

3. The method for preparing the coating according to claim 1 or 2, characterized in that, The preparation method includes: The organic-inorganic hybrid resin, reactive diluent, dispersant, defoamer, leveling agent, rheology modifier, first inert flake filler, second inert flake filler, and optional pigment are mixed evenly to obtain component A. The high-functionality aliphatic amine, the low-viscosity modified alicyclic amine, and the triethylenetetramine are mixed evenly to obtain component B.

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