A modified epoxy coating composition with high pressure resistance and high toughness, its preparation method and application

Abstract

This invention discloses a modified epoxy coating composition with high pressure resistance and high toughness, its preparation method, and its application. The modified epoxy coating composition comprises: a base material and a curing agent; the base material includes epoxy resin, toughening resin, and filler; the curing agent includes a flexible fatty amine, wherein the flexible fatty amine is prepared by reacting a flexible amine, a fatty ketone, and formic acid. The preparation method comprises: mixing epoxy resin, toughening resin, filler, and selectively added or absent additives to form a base material; reacting the flexible amine and fatty ketone to form a flexible fatty amine intermediate, adding formic acid for reduction to obtain the flexible fatty amine, thus obtaining the curing agent; and mixing and reacting the base material and the curing agent to obtain the modified epoxy coating composition. The modified epoxy coating composition of this invention exhibits good film toughness, strong corrosion resistance, good adhesion, and a long pot life, improving the pressure resistance of epoxy coatings on structural components. It can be applied in the field of surface corrosion protection for structural components, especially on negative pressure chambers, ballast tanks, or steel structure surfaces.

Description

Technical Field

[0001] This invention belongs to the field of epoxy coating technology, specifically relating to a modified epoxy coating composition with high pressure resistance and high toughness, its preparation method and application. Background Technology

[0002] Safety is the prerequisite for the development of nuclear power. Currently, nuclear power plant construction adopts the safer and more advanced third-generation nuclear power units. In a nuclear power plant, uranium fuel undergoes fission within the reactor, generating a large amount of heat. High-pressure water carries this heat away, producing steam in a steam generator. This steam drives a turbine, which in turn rotates the generator, continuously generating electricity. Third-generation nuclear power plants have higher technical requirements for coatings than the previous two generations, demanding that the coatings not only be decorative but also possess excellent radiation resistance and protective capabilities. However, most existing coatings are used in second-generation nuclear power plants and their performance is insufficient to meet the standards of third-generation nuclear power plants.

[0003] As is well known, traditional epoxy coatings possess the following characteristics: good adhesion and extremely high wear resistance; excellent resistance to media corrosion and electrical insulation properties; good anti-corrosion performance; and the coating also exhibits strong durability and heat resistance. Furthermore, the curing process is simple, making epoxy coatings widely used in heavy-duty anti-corrosion engineering machinery and other fields. Simultaneously, because epoxy coatings offer some protection against high doses of radiation, and their benzene ring structure has an anti-electron activation effect, they are also used in nuclear power plants. Currently, conventional epoxy coatings have relatively poor toughness, especially at corners, making them prone to decreased adhesion and blistering under pressure changes. Over time, they easily peel off, failing to meet the requirements of large-scale construction. However, paints and coatings used in third-generation nuclear power plants require higher standards of resistance to radiation while also exhibiting superior resistance to cracking, powdering, and peeling. Therefore, developing an epoxy resin composition with a long service life, good anti-corrosion coating performance, and high toughness is of great significance in the field of surface coating anti-corrosion. Summary of the Invention

[0004] The main objective of this invention is to provide a modified epoxy coating composition with high pressure resistance and high toughness, its preparation method and application, so as to overcome the shortcomings of the prior art.

[0005] To achieve the aforementioned objectives, the technical solution adopted by this invention includes:

[0006] One aspect of the present invention provides a modified epoxy coating composition with high pressure resistance and high toughness, comprising: a base material and a curing agent; the base material comprising an epoxy resin, a toughening resin and a filler; the curing agent comprising a flexible fatty amine, wherein the flexible fatty amine is prepared by reacting a flexible amine, a fatty ketone and formic acid.

[0007] Furthermore, the mass ratio of the base material to the curing agent is (2-4):(1-3).

[0008] Furthermore, the base material also includes additives.

[0009] Further, the base material comprises the following components calculated by weight: 35-45 parts epoxy resin, 4-10 parts toughening resin, 55-70 parts filler, and 0-5 parts additives.

[0010] Furthermore, the raw materials for preparing the curing agent include the following components calculated by weight: 88-98 parts of flexible amine, 2-12 parts of fatty ketone, and 0.001-0.05 parts of formic acid.

[0011] Another aspect of the present invention provides a method for preparing the high-pressure resistant and high-toughness modified epoxy coating composition, comprising:

[0012] Epoxy resin, toughening resin, filler, and optional additives are mixed to form a base material;

[0013] A flexible fatty amine and a fatty ketone are reacted to form a flexible fatty amine intermediate, which is then reduced by formic acid to obtain the flexible fatty amine and thus a curing agent.

[0014] The base material and the curing agent are mixed and reacted to obtain the modified epoxy coating composition with high pressure resistance and high toughness.

[0015] Another aspect of the invention provides a coating formed by curing the aforementioned high-pressure resistant and high-toughness modified epoxy coating composition.

[0016] Another aspect of the invention provides the application of the aforementioned high-pressure resistant and high-toughness modified epoxy coating composition or the aforementioned coating in the field of corrosion protection of structural components.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects:

[0018] (1) The high-pressure resistant and high-toughness modified epoxy coating composition provided by the present invention can significantly improve the toughness of the coating film and increase the elongation rate by introducing a flexible amine modified with fatty ketones into the curing agent.

[0019] (2) The modified epoxy coating composition with high pressure resistance and high toughness provided by the present invention has the characteristics of strong corrosion resistance and good adhesion, which improves the pressure resistance of epoxy coating on structural parts; at the same time, it extends the service life of epoxy coating, greatly increases the construction window, improves work efficiency, and reduces construction costs. Detailed Implementation

[0020] In view of the problems existing in the prior art, the inventors of this invention have conducted extensive and in-depth research and have provided a modified epoxy coating composition with high pressure resistance and high toughness, as well as its preparation method and application.

[0021] The following will provide a further explanation of the technical solution, its implementation process, and its principles.

[0022] As one aspect of the technical solution of the present invention, a modified epoxy coating composition with high pressure resistance and high toughness is provided, comprising a base material and a curing agent; the base material comprises epoxy resin, toughening resin and filler; the curing agent comprises flexible fatty amine, wherein the flexible fatty amine is prepared by reacting flexible amine, fatty ketone and formic acid.

[0023] Modifying flexible amines with aliphatic ketones is the key technical means of the solution provided in this invention. In this reaction process, the amines in the flexible amines and aliphatic ketones undergo a Leuckart-Wallach reaction, with some reactions forming secondary and tertiary amines, while also consuming some primary amines, thus reducing the later reaction rate and extending the pot life. At the same time, the long-chain structure of the aliphatic ketones, after being attached to the flexible amines, provides a significant increase in elongation, giving the entire structure greater toughness. Furthermore, because the extended flexible amines have amines at the distal ends of the branches for reaction, the strength in the three-dimensional structure is also significantly improved compared to before. With the dual improvement in elongation and strength, the toughness of the entire coating film is significantly enhanced.

[0024] In some embodiments, the mass ratio of the base material to the curing agent is (2-4):(1-3).

[0025] In some embodiments, the base material also includes additives.

[0026] Preferably, the base material comprises the following components in parts by weight: 35-45 parts epoxy resin, 4-10 parts toughening resin, 55-70 parts filler, and 0-5 parts additives.

[0027] In some embodiments, the epoxy resin may include E51 epoxy resin, but is not limited to this.

[0028] In some embodiments, the toughening resin may include any one or a combination of two or more of rubber, thermoplastic resin, long-chain aliphatic compounds, etc., but is not limited thereto.

[0029] In some preferred embodiments, the toughening resin may include any one or a combination of two of thermoplastic resins, long-chain aliphatic compounds, etc., with long-chain aliphatic compounds being particularly preferred.

[0030] In some embodiments, the long-chain aliphatic compound may be any one or a combination of two or more of AGE, 1,6-hexanediol diglycidyl ether, and 1,4-butanediol diglycidyl ether, preferably 1,6-hexanediol diglycidyl ether, because its chain length is moderate and can achieve a balanced improvement in elongation and strength after reacting with amine.

[0031] In some embodiments, the filler may include any one or a combination of two or more of aluminum tripolyphosphate, zinc tripolyphosphate, precipitated barium sulfate, iron oxide red, quartz powder, etc., but is not limited thereto.

[0032] In some embodiments, the adjuvant may include any one or a combination of two or more of BYK161, PMA, Tego 904W, etc., but is not limited thereto.

[0033] In some embodiments, the raw materials for preparing the curing agent include the following components calculated by weight: 88-98 parts of flexible amine, 2-12 parts of fatty ketone, and 0.001-0.05 parts of formic acid.

[0034] In some embodiments, the flexible amine comprises an epoxy curing agent with high elongation.

[0035] In some preferred embodiments, the flexible amine may include, but is not limited to, any one or a combination of two or more of EPEH-2588, H-120, BS845, etc., with EPEH-2588 being particularly preferred. EPEH-2588 is a custom-developed high-elongation epoxy curing agent, which has improved elongation compared to other curing agents, but the downside is lower strength. Therefore, this invention performs secondary modification to improve its strength, making it a preferred choice in this invention. However, this does not mean that other high-elongation epoxy curing agents are completely outside the scope of this invention.

[0036] Furthermore, the fatty ketone may include any one or a combination of two or more of butanedione, pentaerythrone, tripentanone, etc., preferably pentaerythrone. This is because pentaerythrone has a longer main chain structure, which can provide better flexibility. Compared with butanedione, its rigidity is slightly reduced, but it performs well under high pressure. Pentaerythrone has two reaction sites, which can consume more primary amines, thus extending the pot life of the prepared high-pressure resistant and high-toughness modified epoxy coating composition, which is beneficial for on-site construction.

[0037] As another aspect of the technical solution of the present invention, a method for preparing a high-pressure resistant and high-toughness modified epoxy coating composition includes:

[0038] Epoxy resin, toughening resin, filler, and optional additives are mixed to form a base material;

[0039] A flexible fatty amine and a fatty ketone are reacted to form a flexible fatty amine intermediate, which is then reduced by formic acid to obtain the flexible fatty amine and thus a curing agent.

[0040] The base material and the curing agent are mixed and reacted to obtain the modified epoxy coating composition with high pressure resistance and high toughness.

[0041] In some more specific implementation schemes, the preparation method specifically includes:

[0042] A mixture including flexible amine and fatty ketone is reacted at 40-60℃ for 2-6 hours to form a flexible fatty amine intermediate, which is then dehydrated.

[0043] Then formic acid is added and stirred at 50-60℃ for 3-8 hours to reduce the flexible fatty amine intermediate to a flexible fatty amine, thus obtaining the curing agent.

[0044] In some embodiments, the mass ratio of the flexible amine, fatty ketone, and formic acid is 88-98:2-12:0.001-0.05.

[0045] In some more specific embodiments, the preparation method of the flexible fatty amine may include the following steps:

[0046] a. Add the flexible amine to the reaction vessel;

[0047] b. While stirring in a stirring apparatus, gradually add pentanedione dropwise, keeping the temperature at 40-60℃, and continue the addition process for 2-6 hours to obtain a flexible fatty amine intermediate;

[0048] c. Dehydration treatment;

[0049] d. While stirring, gradually add formic acid to the flexible fatty amine intermediate, keeping the temperature at 50-60℃. The addition process should continue for 3-8 hours. After cooling to room temperature, the flexible fatty amine is obtained.

[0050] As another aspect of the technical solution of the present invention, a coating formed by curing the high-pressure resistant and high-toughness modified epoxy coating composition is provided, wherein the thickness of the coating is between 200 μm and 2 mm.

[0051] As another aspect of the technical solution of the present invention, it also provides the application of the modified epoxy coating composition with high pressure resistance and high toughness, or the coating formed by curing the modified epoxy coating composition with high pressure resistance and high toughness, in the field of surface corrosion protection of structural components.

[0052] Furthermore, the applications include, but are not limited to, applications in negative pressure chambers, ballast chambers, or steel structure surfaces.

[0053] In summary, the high-pressure resistant and high-toughness modified epoxy coating composition provided by this invention can significantly improve the toughness of the coating film and increase the elongation rate by introducing aliphatic ketone-modified flexible amine into the curing agent; it also has the characteristics of strong corrosion resistance and good adhesion, which improves the pressure resistance of epoxy coatings on structural components; at the same time, it extends the pot life of epoxy coatings, greatly increases the construction window, improves work efficiency, and reduces construction costs.

[0054] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Modifications or equivalent substitutions made by those skilled in the art based on their understanding of the technical solutions of this invention, without departing from the spirit and scope of the invention, should be covered within the protection scope of this invention.

[0055] For experiments not specifically described in the examples, the procedures or conditions can be performed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available. For example, the raw materials used in the following examples are as follows: barium sulfate is a product of Taixiang Company, model AB-03N, 4000 mesh precipitated barium sulfate. The commercial selection of other unmentioned raw materials is conventional and does not involve the core technical means of this invention.

[0056] Example 1

[0057] This embodiment provides a modified epoxy coating composition with high pressure resistance and high toughness, wherein the mass ratio of the base material to the curing agent is 2:1, and the base material comprises the following raw materials in parts by weight:

[0058] 35 parts epoxy resin, 5 parts toughening resin, 55 parts filler, and 5 parts additives.

[0059] The epoxy resin is E-51 epoxy resin, specifically NPEL-128 from Nan Ya Epoxy Resin Company; the toughening resin is AGE epoxy reactive diluent; the filler is aluminum tripolyphosphate, precipitated barium sulfate, and iron oxide red; and the additives are BYK161, PMA, and Tego 904W.

[0060] Its curing agent comprises the following raw materials in parts by weight:

[0061] 90 parts of flexible amine, 9.98 parts of fatty ketone, and 0.02 parts of formic acid.

[0062] The flexible amine is selected from the complexed and innovative EPEH-2588 high elongation epoxy curing agent, and the fatty ketone is dimethyl ethyl ketone.

[0063] The curing agent is prepared by:

[0064] Butanedione was gradually added to a reactor containing flexible amine, and the mixture was stirred thoroughly. The temperature was controlled at 50°C, and the mixture was kept at this temperature for 3 hours to allow the reaction to proceed, followed by a dehydration treatment. Then, formic acid was slowly added, and the temperature was controlled at 55°C. The mixture was stirred at a low speed for 4 hours to obtain the curing agent.

[0065] Example 2

[0066] The other operations in this embodiment are the same as in Embodiment 1, except that the toughening resin is 1,6-hexanediol diglycidyl ether.

[0067] Example 3

[0068] The other operations in this embodiment are the same as in Embodiment 1, except that the fatty ketone is pentanedione.

[0069] Example 4

[0070] The other operations in this embodiment are the same as in Embodiment 1, except that its curing agent includes the following raw materials in parts by weight:

[0071] 95 parts of flexible amine, 4.98 parts of fatty ketone, and 0.02 parts of formic acid.

[0072] Example 5

[0073] The other operations in this implementation are the same as in Example 4, except that the mass ratio of base material to curing agent is 4:1.

[0074] Example 6

[0075] The other operations in this embodiment are the same as in Example 4, except that the mass ratio of base material to curing agent is 2:3.

[0076] Example 7

[0077] The other operations in this implementation are the same as in Example 4, except that its base material includes the following raw materials in parts by weight:

[0078] 40 parts epoxy resin, 5 parts toughening resin, 50 parts filler, and 5 parts additives.

[0079] Example 8

[0080] The other operations in this embodiment are the same as in Example 4, except that the flexible amine is BS845 curing agent.

[0081] Example 9

[0082] The other operations in this embodiment are the same as in Example 4, except that the toughening resin is polyetheretherketone.

[0083] Example 10

[0084] The other operations in this embodiment are the same as in Example 4, except that the toughening resin is 1,4-butanediol diglycidyl ether.

[0085] Example 11

[0086] The other operations in this implementation are the same as in Example 4, except that the fatty ketone is pentylene ketone.

[0087] Example 12

[0088] The other operations in this embodiment are the same as in Example 4, except that the preparation method of the curing agent is as follows:

[0089] Pentylene glycol was gradually added to a reactor containing flexible amine, and the mixture was stirred thoroughly. The temperature was controlled at 40°C, and the mixture was kept at this temperature for 3 hours to allow the reaction to proceed. A dehydration process was then performed. The temperature was controlled at 50°C, and the mixture was stirred at low speed for 4 hours to obtain the curing agent.

[0090] Example 13

[0091] The other operations in this embodiment are the same as in Example 4, except that the preparation method of the curing agent is as follows:

[0092] Pentylene glycol was gradually added to a reactor containing flexible amine, and the mixture was stirred thoroughly. The temperature was controlled at 60°C, and the mixture was kept at this temperature for 3 hours to allow the reaction to proceed. A dehydration treatment was then performed. The temperature was controlled at 60°C, and the mixture was stirred at low speed for 4 hours to obtain the curing agent.

[0093] Compare with Example 1

[0094] This comparative example provides a modified epoxy coating composition with high pressure resistance and high toughness, wherein the mass ratio of the base material to the curing agent is 2:1, and the base material comprises the following raw materials in parts by weight:

[0095] 40 parts epoxy resin, 55 parts filler, and 5 parts additives.

[0096] The epoxy resin is E-51 epoxy resin, specifically NPEL-128 from Nan Ya Epoxy Resin Company; the filler is aluminum tripolyphosphate, precipitated barium sulfate, and iron oxide red; and the additives are BYK161, PMA, and Tego 904W.

[0097] Its curing agent comprises the following raw materials in parts by weight:

[0098] 100 parts of flexible amine, wherein the flexible amine is selected from the complexed and innovative EPEH-2588 high elongation epoxy curing agent.

[0099] Compare with Example 2

[0100] The other operations in this comparative example are the same as in Comparative Example 1, except that its base material includes the following raw materials in parts by weight:

[0101] 35 parts epoxy resin, 5 parts toughening resin, 55 parts filler, and 5 parts additives.

[0102] The toughening resin is 1,6-hexanediol diglycidyl ether.

[0103] Its curing agent comprises the following raw materials in parts by weight:

[0104] 100 parts of flexible amine, wherein the flexible amine is selected from the complexed and innovative EPEH-2588 high elongation epoxy curing agent.

[0105] Compare with Example 3

[0106] The other operations in this comparative example are the same as those in comparative example 2, except that the toughening resin is AGE epoxy reactive diluent.

[0107] Compare with Example 4

[0108] The other operations in this comparative example are the same as in Comparative Example 2, except that its base material includes the following raw materials in parts by weight:

[0109] The composition includes 35 parts epoxy resin, 5 parts toughening resin, 55 parts filler, and 5 parts additives. The toughening resin is 1,6-hexanediol diglycidyl ether.

[0110] Its curing agent comprises the following raw materials in parts by weight:

[0111] 98 parts of flexible amine, 1.98 parts of fatty ketone, and 0.02 parts of formic acid.

[0112] Compare with Example 5

[0113] The other operations in this comparative example are the same as in Comparative Example 4, except that its curing agent includes the following raw materials in parts by weight:

[0114] 85 parts of flexible amine, 14.98 parts of fatty ketone, and 0.02 parts of formic acid.

[0115] Compare with Example 6

[0116] The other operations in this comparative example are the same as in Comparative Example 4, except that its curing agent includes the following raw materials in parts by weight:

[0117] 95 parts of flexible amine and 5 parts of fatty ketone.

[0118] The following tests were conducted on the hardness, adhesion, and pot life of the coatings after mixing and applying the base material and curing agent according to the mass ratio described in Examples 1-13 and Comparative Examples 1-6 of the present invention. The test results are shown in Table 1.

[0119] Table 1 Test results of Examples 1-13 and Comparative Examples 1-6

[0120]

[0121] The testing standards are as follows: the service life is tested according to GB / T31416-2015, the hardness is tested according to GB / T6739-2022, the elongation at break is tested according to ISO527-2-2012, the adhesion is tested according to GB / T5210-2006, and the simulated DBA test is tested according to NB / T 20133.2—2012.

[0122] Comparative Example 1 serves as a control case. It does not contain toughening resin, nor does it modify the flexible amine with fatty ketones. Although it has high hardness, it not only has a short service life, but also low elongation at break and adhesion of the coating. This shows that the typical implementation case represented by Example 4 can not only achieve the effect of extending the service life of the coating, but also significantly improve various comprehensive properties.

[0123] Compared to Comparative Example 1, Comparative Example 2 showed a significantly improved pot life and a more noticeable increase in elongation. This is because the toughening resin 1,6-hexanediol diglycidyl ether in the base material can provide a good elongation, resulting in a better elongation at break of the coating. However, the coating still blistered and cracked.

[0124] Compared to Comparative Example 2, Comparative Example 3 showed a slight improvement in the elongation at break and adhesion of the coating. This is because the AGE chain length is longer than that of 1,6-hexanediol diglycidyl ether, resulting in a lower crosslinking density and thus greater softness. In the DBE test, the coating only blistered and did not crack.

[0125] Compared to Control Example 3, Example 1 introduced dimethylglyoxal modification and pre-reacted to synthesize an aliphatic flexible amine, thus reducing the hardness of the coating.

[0126] Compared to Example 1, Example 2 uses 1,6-hexanediol diglycidyl ether, which has a higher crosslinking density and improves the elongation at break of the coating.

[0127] Compared to Example 2, Example 3 uses pentaerythritol for modification. The increase in elongation is due to the use of pentaerythritol as a fatty amine for modification. While maintaining the same reaction sites, the main chain length is increased, and the cross-linked spatial network structure is more elastic, which can significantly improve the elongation at break of the coating.

[0128] Compared to Example 3, Example 4 reduced the content of pentanedione and the amount of flexible amine, thus shortening the pot life. At the same time, the hardness of the coating was significantly improved, and the coating did not blister or crack.

[0129] Compared to Example 4, Example 5 has a lower proportion of curing agent, thus reducing the extended coating life and improved elongation at break effect brought about by the flexible amine. The coating did not blister or crack.

[0130] Compared to Example 4, Example 6 has a lower proportion of base material and a slightly higher amount of flexible amine, which improves the elongation of the coating but reduces adhesion. The coating did not blister or crack.

[0131] Compared to Example 4, Example 7 shows an increased proportion of epoxy resin in the base material, resulting in a greater amount of reaction. Consequently, the pot life of the coating is shortened, and the coating does not blister or crack.

[0132] Compared to Example 4, Example 8 uses BS845 as the curing agent. Compared to 2588, it is less flexible, so the elongation at break of the coating decreases. The coating does not blister or crack.

[0133] Compared to Example 4, Example 9 uses polyetheretherketone as the toughening resin, which is less flexible. Therefore, the elongation at break of the coating is also lower than that of Example 4, and the coating does not blister or crack.

[0134] Compared to Example 4, Example 10 uses 1,4-butanediol diglycidyl ether as the toughening resin, which has a shorter overall chain length and therefore provides lower flexibility. Consequently, the elongation at break of the coating is also lower, and the coating does not bubble or crack.

[0135] Compared to Example 4, Example 11 uses glycerol for modification, which has more reaction sites but shorter chain length and higher crosslinking density. Therefore, the elongation at break of the coating decreases, while the adhesion is greatly improved, so the coating does not blister or crack.

[0136] Compared to Example 4, Example 12 had a lower reaction temperature for the curing agent, which prevented the formic acid from fully catalyzing the reaction. The reaction was insufficient, resulting in an inadequate amount of flexible amine. Consequently, the elongation at break of the coating decreased, and the coating did not blister or crack.

[0137] Compared to Example 4, Example 13 had a higher reaction temperature and a higher degree of reaction in the curing agent, resulting in an excessive amount of flexible amine. As a result, the pot life of the coating was extended, but the adhesion decreased, and the coating did not blister or crack.

[0138] Compared to Control Example 2, Comparative Example 3 modified the flexible amine with aliphatic ketones. This resulted in a significantly improved pot life of the coating, along with slight improvements in elongation at break and adhesion, but a decrease in hardness. The main reason for this is likely the use of dimethyl ethyl ketone (DME) for modification, which effectively reduced reactivity and extended the pot life.

[0139] Compared to Example 4, the content of pentanedione in Comparative Example 4 was further reduced, resulting in an insufficient amount of flexible amine, and therefore the pot life of the coating could not be improved.

[0140] Compared to Example 3, the content of pentanedione in Comparative Example 5 was further increased. The excessive amount of flexible amine led to an excessively long service life of the coating and poor overall hardness of the paint film.

[0141] Compared to Example 4, Comparative Example 6 did not include formic acid modification, which prevented the flexible amine intermediate from reacting further and thus prevented the formation of amine products, making it impossible to react with the base material.

[0142] As can be seen from the above representative embodiments and comparative embodiments, the high-pressure resistant and high-toughness modified epoxy coating composition provided by the embodiments of the present invention, by introducing fatty ketones into the flexible amine to form a flexible fatty amine, can extend the service life of the high-pressure resistant epoxy coating, significantly increase the construction window, and improve work efficiency; increase flexibility, release the stress of the paint film under high pressure, disperse pressure, and increase adhesion; and at the same time have the characteristics of strong corrosion resistance and good adhesion.

[0143] In addition, the inventors of this case also conducted experiments with other raw materials, process operations, and process conditions described in this specification, referring to the aforementioned embodiments, and obtained relatively ideal results in all cases.

[0144] Although the invention has been described with reference to illustrative embodiments, those skilled in the art will understand that various other changes, omissions, and / or additions can be made without departing from the spirit and scope of the invention, and that elements of the described embodiments can be substituted with substantially equivalents. Furthermore, many modifications can be made without departing from the scope of the invention to adapt particular situations or materials to the teachings of the invention. Therefore, this document is not intended to limit the invention to the specific embodiments disclosed for carrying out the invention, but rather to include all embodiments falling within the scope of the appended claims.

Claims

1. A modified epoxy coating composition with high pressure resistance and high toughness, characterized in that, The product comprises a base material and a curing agent; the mass ratio of the base material to the curing agent is (2-4):(1-3), and the base material comprises the following components by weight: 35-45 parts epoxy resin, 4-10 parts toughening resin, 55-70 parts filler, and 0-5 parts additives; the curing agent comprises a flexible fatty amine, which is prepared by reacting a flexible amine, a fatty ketone, and formic acid. The reaction specifically includes: reacting a mixture of flexible amine and fatty ketone at 40-60℃ for 2-6 hours to form a flexible fatty amine intermediate, and then dehydrating it; then adding formic acid and stirring at 50-60℃ for 3-8 hours to reduce the flexible fatty amine intermediate to a flexible fatty amine, thereby obtaining the curing agent; wherein the raw materials for preparing the curing agent comprise the following components by weight: 88-98 parts flexible amine, 2-12 parts fatty ketone, and 0.001-0.05 parts formic acid; The toughening resin is a long-chain aliphatic compound, which includes any one or a combination of two or more of AGE, 1,6-hexanediol diglycidyl ether, and 1,4-butanediol diglycidyl ether. The flexible amine is an epoxy curing agent with high elongation, which includes any one or a combination of two or more of EPEH-2588, H-120, and BS845.

2. The modified epoxy coating composition with high pressure resistance and high toughness according to claim 1, characterized in that: The epoxy resin includes E51 epoxy resin.

3. The modified epoxy coating composition with high pressure resistance and high toughness according to claim 1, characterized in that: The long-chain aliphatic compound is 1,6-hexanediol diglycidyl ether.

4. The modified epoxy coating composition with high pressure resistance and high toughness according to claim 1, characterized in that: The filler includes any one or a combination of two or more of the following: aluminum tripolyphosphate, zinc tripolyphosphate, precipitated barium sulfate, iron oxide red, and quartz powder.

5. The high-pressure resistant and high-toughness modified epoxy coating composition according to claim 1, characterized in that: The adjuvants include any one or a combination of two or more of BYK161, PMA, and Tego 904W.

6. The modified epoxy coating composition with high pressure resistance and high toughness according to claim 1, characterized in that: The flexible amine EPEH-2588.

7. The modified epoxy coating composition with high pressure resistance and high toughness according to claim 1, characterized in that: The fatty ketones include any one or a combination of two or more of butanedione, pentadione, and tripentanone.

8. The modified epoxy coating composition with high pressure resistance and high toughness according to claim 7, characterized in that: The fatty ketone is pentanedione.

9. A method for preparing the high-pressure resistant and high-toughness modified epoxy coating composition according to any one of claims 1-8, characterized in that, include: Epoxy resin, toughening resin, filler and additives are mixed to form a base material; A mixture including flexible amine and fatty ketone is reacted at 40-60℃ for 2-6 hours to form a flexible fatty amine intermediate, which is then dehydrated. Then formic acid was added and stirred at 50-60℃ for 3-8 hours to reduce the flexible fatty amine intermediate to flexible fatty amine, thus obtaining the curing agent. The base material and the curing agent are mixed and reacted to obtain the modified epoxy coating composition with high pressure resistance and high toughness.

10. The preparation method according to claim 9, characterized in that, include: The mass ratio of the flexible amine, fatty ketone, and formic acid is 88-98:2-12:0.001-0.

05.

11. A coating formed by curing the modified epoxy coating composition with high pressure resistance and high toughness according to any one of claims 1-8, characterized in that: The coating thickness is 200μm-2mm.

12. The application of the high-pressure resistant and high-toughness modified epoxy coating composition of any one of claims 1-8 or the coating of claim 11 in the field of corrosion protection of structural components.

13. The application according to claim 12, characterized in that: The applications include those in negative pressure chambers, ballast chambers, or on the surface of steel structures.

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