Temperature-resistant solvent-free epoxy coating as well as preparation method and application thereof

Abstract

The invention provides a solvent-free epoxy coating as well as a preparation method and application thereof, the solvent-free epoxy coating comprises a component A and a component B, and the weight ratio of the component A to the component B is 1: (0.18-0.23); the component A is prepared from the following components in parts by weight: 1 part of bisphenol F epoxy resin, 0.4 to 0.5 part of novolac epoxy resin, 0.2 to 0.4 part of reactive diluent, 0.2 to 0.3 part of sericite powder, 0.02 to 0.03 part of carbon nanofiber, 1.4 to 1.7 parts of pigment filler, 0.010 to 0.015 part of defoaming agent, 0.003 to 0.006 part of dispersing agent, 0.005 to 0.010 part of flatting agent and 0.006 to 0.009 part of base material wetting agent; the component B comprises 1 part of an aromatic amine curing agent, 0.4-0.6 part of an alicyclic amine curing agent and 0.02-0.03 part of a tertiary amine curing accelerator. The method is beneficial to shortening the anti-corrosion construction period of petrochemical equipment.

Description

Technical Field

[0001] This invention relates to the field of epoxy coating technology, and more specifically, to a heat-resistant solvent-free epoxy coating and its preparation method. Background Technology

[0002] Because pressure vessels and storage tanks in the petroleum, petrochemical, and chemical industries are enclosed spaces with complex internal structures and highly corrosive stored media, solvent-free epoxy coatings with good anti-corrosion properties are generally used. During later maintenance, on-site shutdown and tank opening are required for repairs. To minimize the impact on production, the construction cycle is generally short, requiring the coating to have a fast curing speed. At the same time, because some containers and storage tanks operate at high temperatures, the internal anti-corrosion coatings also require good heat resistance.

[0003] While ordinary bisphenol A solvent-free epoxy coatings possess good anti-corrosion properties and adhesion, their drying and curing processes require considerable time, typically 7-10 days at room temperature, and their long-term operating temperature is generally below 80℃. Ordinary phenolic epoxy coatings, due to their high functionality and good heat resistance, fail to meet relevant standards in terms of coating flexibility, adhesion, and other mechanical properties, and their curing time at room temperature also requires 5-7 days, making them unsuitable for on-site maintenance and corrosion protection needs. Therefore, the development of heat-resistant solvent-free epoxy coatings with good physical and mechanical properties and anti-corrosion performance, capable of rapid curing, is urgently needed as a research direction for solving the corrosion protection of containers and tanks operating at high temperatures. Summary of the Invention

[0004] In view of this, the present invention proposes a heat-resistant solvent-free epoxy coating, its preparation method and application, aiming to solve the problems in the existing petrochemical field where the anti-corrosion construction period for pipelines, storage tanks and pressure vessels in high-temperature environments is long and the anti-corrosion effect is poor, affecting normal production.

[0005] Specifically, the first aspect of this invention provides a heat-resistant solvent-free epoxy coating, comprising component A and component B, wherein the weight ratio of component A to component B is 1:0.18-0.23; component A comprises the following components in parts by weight: 1 part bisphenol F epoxy resin, 0.4-0.5 parts phenolic epoxy resin, 0.2-0.4 parts reactive diluent, 0.2-0.3 parts sericite powder, 0.02-0.03 parts carbon nanofiber, 1.4-1.7 parts pigments and fillers, 0.010-0.015 parts defoamer, 0.003-0.006 parts dispersant, 0.005-0.010 parts leveling agent, and 0.006-0.009 parts substrate wetting agent; component B comprises the following components in parts by weight: 1 part aromatic amine curing agent, 0.4-0.6 parts alicyclic amine curing agent, and 0.02-0.03 parts tertiary amine curing accelerator.

[0006] Further, in the above-mentioned heat-resistant solvent-free epoxy coating, component A comprises the following components in parts by weight: 1 part bisphenol F epoxy resin, 0.43 parts phenolic epoxy resin, 0.28 parts reactive diluent, 0.25 parts sericite powder, 0.023 parts carbon nanofiber, 1.6 parts pigments and fillers, 0.012 parts defoamer, 0.005 parts dispersant, 0.008 parts leveling agent, and 0.008 parts substrate wetting agent; component B comprises the following components in parts by weight: 1 part aromatic amine curing agent, 0.5 parts alicyclic amine curing agent, and 0.025 parts tertiary amine curing accelerator.

[0007] Furthermore, in the above-mentioned heat-resistant solvent-free epoxy coating, the bisphenol F epoxy resin is SMF-170S bisphenol F epoxy resin, the phenolic epoxy resin is F-53 bisphenol A phenolic epoxy resin, and the reactive diluent is SM-80 1,6-hexanediol diglycidyl ether.

[0008] Furthermore, in the above-mentioned heat-resistant solvent-free epoxy coating, the sericite powder is wet-processed sericite powder with an average particle size of 15-20 μm and a thickness of <5 μm; and / or the carbon nanofibers are HQNANO-CNTs-009-4 type carbon nanofibers.

[0009] Furthermore, in the above-mentioned heat-resistant solvent-free epoxy coating, the pigments and fillers include the following components in parts by weight: 0.01 to 0.04 parts of organobentonite, 0.55 to 0.60 parts of wollastonite powder, 0.37 to 0.45 parts of rutile titanium dioxide, 0.04 to 0.07 parts of carbon black, 0.25 to 0.30 parts of talc powder, and 0.18 to 0.24 parts of barite powder.

[0010] Further, in the above-mentioned heat-resistant solvent-free epoxy coating, the defoamer is at least one of TEGO Airex 902W polyether silicone defoamer, Efka EFKA-2010 non-organosilicone defoamer, and BYK-066N silicone defoamer; and / or the dispersant is at least one of TEGO Dispers 685 polymer dispersant, BYK-P104S dispersant, and Dow PPOLYOX TMWSR N-60K polyethylene oxide dispersant; and / or the leveling agent is at least one of TEGO Glide 450 polyether silicone copolymer leveling agent, TEGO Glide 410 polyether silicone copolymer leveling agent, and BYK-333 polyether modified silicone leveling agent; and / or the substrate wetting agent is at least one of TEGO Wet 270 polyether silicone copolymer substrate wetting agent, TEGO Wet... At least one of the following: Type 280 polyether siloxane copolymer substrate wetting agent and BYK-346 polyether siloxane copolymer wetting agent.

[0011] Furthermore, in the above-mentioned heat-resistant solvent-free epoxy coating, the aromatic amine curing agent is at least one of SM113 aromatic amine curing agent, Aradur 5200 aromatic amine curing agent, and BD10 modified aromatic amine curing agent; the alicyclic amine curing agent is at least one of Ancamine 2753 alicyclic amine curing agent, EPIKURE F 205 alicyclic amine curing agent, and WSG-322 modified alicyclic amine curing agent; and the tertiary amine curing accelerator is at least one of K-54 tertiary amine curing accelerator and DMP-30 tertiary amine curing accelerator.

[0012] A second aspect of this invention provides a method for preparing a heat-resistant solvent-free epoxy coating, comprising the following steps:

[0013] Step 1: Add phenolic epoxy resin and reactive diluent to bisphenol F epoxy resin in sequence, stir once to disperse the components evenly, and cool to room temperature to obtain epoxy resin liquid.

[0014] Step 2: Add the defoamer, dispersant, leveling agent and substrate wetting agent to the above epoxy resin liquid, and stir twice to make the components evenly dispersed to obtain an epoxy resin mixed solution.

[0015] Step 3: Add carbon nanofibers and pigments / fillers to the resin mixture solution in sequence, and stir three times to ensure that the components are evenly dispersed to obtain the coating mixture;

[0016] Step 4: Grind the coating mixture obtained in Step 3 to obtain the coating base liquid, wherein the grinding fineness is ≤80μm;

[0017] Step 5: Add sericite powder to the coating base liquid obtained in Step 4, and stir four times to ensure that the components are evenly dispersed, thus obtaining component A of the heat-resistant solvent-free epoxy coating.

[0018] Step 6: Add the cycloaliphatic amine curing agent and the tertiary amine curing accelerator to the aromatic amine curing agent in sequence, and stir five times to ensure that the components are evenly dispersed, so as to obtain component B of the heat-resistant solvent-free epoxy coating.

[0019] Step 7: Mix component A and component B evenly according to the weight ratio of the two components to obtain the heat-resistant solvent-free epoxy coating.

[0020] Furthermore, in the above preparation method, the temperature of the first stirring is 10℃-40℃, the stirring speed is 1500-2000 r / min, and the stirring time is 15-20 min; and / or the temperature of the second stirring is 10℃-40℃, the stirring speed is 1000-1500 r / min, and the stirring time is 10-15 min; the temperature of the third stirring is 10℃-40℃, the stirring speed is 1500-2000 r / min, and the stirring time is 20-25 min; the temperature of the fourth stirring is 10℃-40℃, the stirring speed is 2000-2500 r / min, and the stirring time is 25-30 min; the temperature of the fifth stirring is 10℃-30℃, the stirring speed is 1000-1500 r / min, and the stirring time is 10-15 min.

[0021] This invention also provides an application of a heat-resistant solvent-free epoxy coating in the internal and external corrosion protection of petrochemical equipment at temperatures below 120°C.

[0022] The temperature-resistant solvent-free epoxy coating provided by this invention has the following beneficial effects:

[0023] 1. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention uses bisphenol A phenolic epoxy resin and bisphenol F epoxy resin as the film-forming resin system. Two hydrogen atoms of bisphenol F epoxy resin replace the methyl functional group in bisphenol A epoxy resin. In addition to having the basic characteristics of bisphenol A epoxy resin, its viscosity is reduced, making it suitable for solvent-free coatings. The epoxy group functionality of bisphenol A phenolic epoxy resin is greater than 2, and the crosslinking density is high, which can improve the temperature resistance and corrosion resistance of the coating.

[0024] 2. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention uses aromatic amine curing agent and alicyclic amine curing agent. The molecular structures of aromatic amine and alicyclic amine contain stable benzene ring structure and alicyclic structure, respectively, which improves the heat distortion temperature and thermal decomposition temperature of the coating. At the same time, the two types of curing agents undergo cross-linking reaction with the two types of epoxy resin to form an interpenetrating network, which improves the density, strength and comprehensive anti-corrosion performance of the coating.

[0025] 3. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention uses a tertiary amine curing accelerator. The nitrogen atom of the tertiary amine molecule has a pair of lone pairs of electrons, which can nucleophilically attack the epoxy group and catalyze the self-ring-opening curing of the epoxy resin. This can significantly improve the curing reaction rate of the epoxy resin and shorten the drying and curing time.

[0026] 4. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention uses carbon nanofibers. Carbon fibers have excellent chemical and thermal stability. They can form a uniform heat-transferring network structure inside the coating, reducing cracks caused by local thermal stress concentration inside the coating, thus giving the coating good stability at high temperatures. At the same time, carbon nanofibers are nanoscale materials with volume and surface effects, which greatly enhance the bonding strength of unsaturated bonds between the coating and the protected metal, improving the coating's adhesion and overall anti-corrosion performance.

[0027] 5. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention has good physical properties and anti-corrosion properties, adhesion ≥18MPa, heat resistance (200℃, 300h) with the coating intact, high temperature and high pressure resistance (5% NaCl aqueous solution, 120℃, 10MPa) with the coating intact for 1000h, cathodic disbondment resistance (65℃, -1.5v, 48h) ≤5mm, and salt spray resistance with the coating intact for 3000h.

[0028] 6. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention has the characteristics of fast drying and curing speed. At 25℃, the surface drying time of the coating is ≤0.5h, the actual drying time is ≤2h, and the curing time of the coating is ≤3d.

[0029] 7. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention is suitable for internal and external corrosion protection of petrochemical pipelines, storage tanks and pressure vessels and other equipment at temperatures below 120℃. It can achieve rapid drying and curing, shortening the construction cycle. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below.

[0031] The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention comprises component A and component B, and the weight ratio of component A to component B is 1:0.18-0.23. Component A comprises the following components in parts by weight: 1 part bisphenol F epoxy resin, 0.4-0.5 parts phenolic epoxy resin, 0.2-0.4 parts reactive diluent, 0.2-0.3 parts sericite powder, 0.02-0.03 parts carbon nanofiber, 1.4-1.7 parts pigments and fillers, 0.010-0.015 parts defoamer, 0.003-0.006 parts dispersant, 0.005-0.010 parts leveling agent, and 0.006-0.009 parts substrate wetting agent. Component B comprises the following components in parts by weight: 1 part aromatic amine curing agent, 0.4-0.6 parts alicyclic amine curing agent, and 0.02-0.03 parts tertiary amine curing accelerator.

[0032] In this embodiment, preferably, the weight ratio of component A to component B is 1:0.22.

[0033] Component A comprises the following components in parts by weight: 1 part bisphenol F epoxy resin, 0.43 parts phenolic epoxy resin, 0.28 parts reactive diluent, 0.25 parts sericite powder, 0.023 parts carbon nanofiber, 1.6 parts pigments and fillers, 0.012 parts defoamer, 0.005 parts dispersant, 0.008 parts leveling agent, and 0.008 parts substrate wetting agent; Component B comprises the following components in parts by weight: 1 part aromatic amine curing agent, 0.5 parts alicyclic amine curing agent, and 0.025 parts tertiary amine curing accelerator.

[0034] Furthermore, the specific selections of each component in component A are as follows:

[0035] The bisphenol F epoxy resin is at least one selected from SMF-170S bisphenol F epoxy resin, SMF-170 bisphenol F epoxy resin, and NPEF-170 bisphenol F epoxy resin. The phenolic epoxy resin is at least one selected from F-53 bisphenol A phenolic epoxy resin, F-44 bisphenol A phenolic epoxy resin, and F-51 bisphenol A phenolic epoxy resin; the reactive diluent is at least one selected from SM-80 1,6-hexanediol diglycidyl ether and AGE C12-14 alcohol glycidyl ether.

[0036] In this embodiment, SMF-170S bisphenol F epoxy resin is modified with F-53 bisphenol A phenolic epoxy resin. The amount of SMF-170S bisphenol F epoxy resin is 1 part, and the amount of phenolic epoxy resin is 0.4 to 0.5 parts. Through physical modification, the two resins are mixed and used to improve the temperature resistance of SMF-170S bisphenol F epoxy resin.

[0037] Sericite powder is wet-processed sericite powder with an average particle size of 15-20 μm and a thickness of <5 μm. Mica powder of this size belongs to the category of flake fillers. By arranging them in parallel in the coating, the penetration path of the medium can be greatly extended, thereby improving the coating's impermeability and corrosion resistance.

[0038] The carbon nanofibers are HQNANO-CNTs-009-4 type carbon nanofibers. These carbon nanofibers have a linear structure and, when uniformly distributed and interlocked within the coating, form a network structure. This creates a uniform heat-transferring network within the coating, utilizing their excellent thermal conductivity to conduct and disperse localized heat. This reduces cracking caused by concentrated localized thermal stress within the coating, resulting in good stability of the coating at high temperatures.

[0039] The pigments and fillers are at least one of organic bentonite, wollastonite powder, rutile titanium dioxide, carbon black, talc powder and barite powder.

[0040] Preferably, the pigments and fillers comprise the following components in parts by weight: 0.01 to 0.04 parts of organobentonite, 0.55 to 0.60 parts of wollastonite powder, 0.37 to 0.45 parts of rutile titanium dioxide, 0.04 to 0.07 parts of carbon black, 0.25 to 0.30 parts of talc powder, and 0.18 to 0.24 parts of barite powder.

[0041] The defoamer is at least one of TEGO Airex 920W polyether silicone defoamer, Efka EFKA-2010 non-organosilicone defoamer, and BYK-066N organosilicone defoamer; the dispersant is at least one of TEGO Dispers 685 polymer dispersant, BYK-P104S dispersant, and Dow PPOLYOX TMWSR N-60K polyethylene oxide dispersant; the leveling agent is at least one of TEGO Glide 450 polyether silicone copolymer leveling agent, TEGO Glide 410 polyether silicone copolymer leveling agent, and BYK-333 polyether modified silicone leveling agent; the substrate wetting agent is at least one of TEGO Wet 270 polyether silicone copolymer substrate wetting agent, TEGO Wet 280 polyether silicone copolymer substrate wetting agent, and BYK-346 polyether silicone copolymer wetting agent.

[0042] The specific selections of each component in component B are as follows:

[0043] The aromatic amine curing agent is at least one of SM113 aromatic amine curing agent, Aradur 5200 aromatic amine curing agent, and BD10 modified aromatic amine curing agent; the alicyclic amine curing agent is at least one of Ancamine 2753 alicyclic amine curing agent, EPIKUREF 205 alicyclic amine curing agent, and WSG-322 modified alicyclic amine curing agent; the tertiary amine curing accelerator is at least one of K-54 tertiary amine curing accelerator and DMP-30 tertiary amine curing accelerator.

[0044] All components of components A and B used in the embodiments of the present invention described above are commercially available products.

[0045] This invention also provides a heat-resistant solvent-free epoxy coating and its preparation method, comprising the following steps:

[0046] Step 1: Add phenolic epoxy resin and reactive diluent to bisphenol F epoxy resin in sequence, stir once to disperse the components evenly, and cool to room temperature to obtain epoxy resin liquid.

[0047] Specifically, the temperature of the first stirring is 10℃~40℃, the stirring speed is 1500~2000r / min, and the stirring time is 15~20min.

[0048] Step 2: Add the defoamer, dispersant, leveling agent and substrate wetting agent to the above epoxy resin liquid, and stir twice to make the components evenly dispersed to obtain an epoxy resin mixed solution.

[0049] Specifically, the temperature of the secondary stirring is 10℃-40℃, the speed of the secondary stirring is 1000~1500r / min, and the time of the secondary stirring is 10~15min.

[0050] Step 3: Add carbon nanofibers and pigments / fillers to the resin mixture solution in sequence, and stir three times to ensure that the components are evenly dispersed to obtain the coating mixture.

[0051] Specifically, pigments and fillers can be added in the following order: organic bentonite, wollastonite powder, rutile titanium dioxide, carbon black, talc powder, and barite powder.

[0052] The temperature of the three stirrings is 10℃-40℃, the stirring speed is 1500~2000r / min, and the stirring time is 20~25min.

[0053] Step 4: Grind the coating mixture obtained in Step 3 to obtain the coating base liquid, wherein the grinding fineness is ≤80μm.

[0054] Specifically, the grinding equipment can be a sand mill, and the grinding time is 0.5 to 1.0 hours.

[0055] Step 5: Add sericite powder to the coating base liquid obtained in Step 4, and stir four times to ensure that the components are evenly dispersed, thus obtaining component A of the heat-resistant solvent-free epoxy coating.

[0056] Specifically, the temperature of the four stirrings is 10℃-40℃, the stirring speed is 2000-2500 r / min, and the stirring time is 25-30 min.

[0057] Step 6: Add the cycloaliphatic amine curing agent and the tertiary amine curing accelerator to the aromatic amine curing agent in sequence, and stir five times to ensure that the components are evenly dispersed, thus obtaining component B of the heat-resistant solvent-free epoxy coating.

[0058] Specifically, the temperature of the five stirrings is 10℃-30℃, the stirring speed is 1000-1500 r / min, and the stirring time is 10-15 min.

[0059] Step 7: Mix component A and component B evenly according to the weight ratio of the two components to obtain the heat-resistant solvent-free epoxy coating.

[0060] The heat-resistant solvent-free epoxy coating prepared in this invention can be used for internal wall corrosion protection of pressure vessels, oil tanks, and other enclosed spaces that require resistance to media and temperature. It can achieve rapid curing and rapid application, and has good anti-corrosion performance and temperature resistance. It can also be used in high-temperature and high-pressure corrosive environments with a temperature of 120℃ and a pressure of 30MPa. The rapid curing of the heat-resistant solvent-free epoxy coating can achieve complete drying of the coating within 2 hours after application, and the curing time of the coating at 25℃ is ≤3 days.

[0061] Based on the same inventive concept, this invention also provides an application of a high-temperature resistant solvent-free epoxy coating for internal and external corrosion protection of petrochemical equipment below 120°C. For example, the high-temperature resistant solvent-free epoxy coating in this invention is suitable for internal and external corrosion protection of petrochemical pipelines, storage tanks, and pressure vessels below 120°C.

[0062] The present invention will now be described in detail with reference to several specific embodiments.

[0063] Example 1

[0064] Step (1): 0.43 parts of F-53 bisphenol A phenolic epoxy resin and 0.28 parts of SM-80 1,6-hexanediol diglycidyl ether were added to 1 part of SMF-170S bisphenol F epoxy resin in sequence, and stirred at 1800 r / min for 15 min, while controlling the temperature to be below 40℃.

[0065] In step (2), 0.012 parts of TEGO Airex 902W polyether siloxane defoamer, 0.005 parts of TEGODispers 685 polymer dispersant, 0.008 parts of TEGO Glide 450 polyether siloxane copolymer leveling agent, and 0.008 parts of TEGO Wet 270 polyether siloxane copolymer substrate wetting agent are added sequentially to the epoxy resin liquid obtained in step (1). The mixture is stirred at 1000 r / min for 15 min, and the temperature is controlled to be below 40℃.

[0066] In step (3), 0.023 parts of HQNANO-CNTs-009-4 type carbon nanofibers, 0.03 parts of organic bentonite, 0.58 parts of wollastonite powder, 0.42 parts of rutile titanium dioxide, 0.05 parts of carbon black, 0.30 parts of talc powder and 0.22 parts of barite powder are added sequentially to the resin mixture obtained in step (2), and stirred at a speed of 1500 r / min for 25 min, while controlling the temperature to be below 40℃.

[0067] Step (4): Grind the coating mixture obtained in step (3) using a sand mill for 1.0 h to obtain the coating base liquid, and control the grinding fineness to be ≤80μm;

[0068] Step (5): Add 0.25 parts of wet sericite powder with an average particle size of 15-20 μm to the coating base liquid obtained in step (4), stir at a speed of 2000 r / min for 30 min, and control the temperature below 40℃ to obtain component A of fast-drying heat-resistant solvent-free epoxy coating.

[0069] Step (6): 0.5 parts of Ancamine 2753 alicyclic amine curing agent and 0.025 parts of K-54 tertiary amine curing accelerator are added to 1 part of SM113 aromatic amine curing agent in sequence. Stir at 1200 r / min for 15 min and control the temperature below 30℃ to obtain component B of fast-drying heat-resistant solvent-free epoxy coating.

[0070] Step (7): Mix component A and component B in a weight ratio of 1:0.22 to obtain the fast-drying, heat-resistant, solvent-free epoxy coating.

[0071] The fast-drying, heat-resistant, solvent-free epoxy coating prepared in Example 1 was coated on a test panel, and its relevant properties were tested. The properties of the coating and its coating are shown in Table 1.

[0072] Table 1. Performance of the fast-drying, heat-resistant, solvent-free epoxy coating prepared in Example 1

[0073]

[0074]

[0075] Example 2

[0076] Step (1): 0.5 parts of F-53 bisphenol A phenolic epoxy resin and 0.35 parts of SM-80 1,6-hexanediol diglycidyl ether are added to 1 part of SMF-170S bisphenol F epoxy resin in sequence, and stirred at 2000 r / min for 15 min, while controlling the temperature to be below 40℃.

[0077] In step (2), 0.014 parts of TEGO Airex 902W polyether siloxane defoamer, 0.004 parts of TEGODispers 685 polymer dispersant, 0.006 parts of TEGO Glide 450 polyether siloxane copolymer leveling agent, and 0.007 parts of TEGO Wet 270 polyether siloxane copolymer substrate wetting agent are added sequentially to the epoxy resin liquid obtained in step (1). The mixture is stirred at a speed of 1200 r / min for 15 min, and the temperature is controlled to be below 40℃.

[0078] In step (3), 0.028 parts of HQNANO-CNTs-009-4 type carbon nanofibers, 0.03 parts of organic bentonite, 0.55 parts of wollastonite powder, 0.40 parts of rutile titanium dioxide, 0.06 parts of carbon black, 0.28 parts of talc powder and 0.19 parts of barite powder are added sequentially to the resin mixture obtained in step (2), and stirred at a speed of 1700 r / min for 25 min, while controlling the temperature to be below 40℃.

[0079] Step (4): Grind the coating mixture obtained in step (3) using a sand mill for 0.5 hours to obtain the coating base liquid, and control the grinding fineness to be ≤80μm;

[0080] Step (5): Add 0.30 parts of wet sericite powder with an average particle size of 15-20 μm to the coating base liquid obtained in step (4), stir at a speed of 2200 r / min for 30 min, and control the temperature below 40℃ to obtain component A of fast-drying heat-resistant solvent-free epoxy coating.

[0081] Step (6): 0.45 parts of Ancamine 2753 alicyclic amine curing agent and 0.03 parts of K-54 tertiary amine curing accelerator are added to 1 part of SM113 aromatic amine curing agent in sequence. Stir at 1300 r / min for 10 min and control the temperature below 30℃ to obtain component B of fast-drying heat-resistant solvent-free epoxy coating.

[0082] Step (7): Mix component A and component B in a weight ratio of 1:0.18 to obtain the fast-drying, heat-resistant, solvent-free epoxy coating.

[0083] The properties of the fast-drying, heat-resistant, solvent-free epoxy coating prepared in Example 2 were tested, and the properties of the coating and its coating are shown in Table 2.

[0084] Table 2 shows the performance of the fast-drying, heat-resistant, solvent-free epoxy coating prepared in Example 2.

[0085]

[0086] Example 3

[0087] Step (1): 0.4 parts of F-53 bisphenol A phenolic epoxy resin and 0.32 parts of SM-80 1,6-hexanediol diglycidyl ether were added to 1 part of SMF-170S bisphenol F epoxy resin in sequence, and stirred at 1500 r / min for 20 min, while controlling the temperature to be below 40℃.

[0088] In step (2), 0.015 parts of TEGO Airex 902W polyether siloxane defoamer, 0.006 parts of TEGO Dispers 685 polymer dispersant, 0.010 parts of TEGO Glide 450 polyether siloxane copolymer leveling agent, and 0.009 parts of TEGO Wet 270 polyether siloxane copolymer substrate wetting agent are added sequentially to the epoxy resin liquid obtained in step (1). The mixture is stirred at a speed of 1500 r / min for 12 min, and the temperature is controlled to be below 40℃.

[0089] In step (3), 0.025 parts of HQNANO-CNTs-009-4 type carbon nanofibers, 0.04 parts of organic bentonite, 0.56 parts of wollastonite powder, 0.45 parts of rutile titanium dioxide, 0.04 parts of carbon black, 0.35 parts of talc powder and 0.16 parts of barite powder are added sequentially to the resin mixture obtained in step (2), and stirred at a speed of 1900 r / min for 20 min, while controlling the temperature to be below 40℃.

[0090] Step (4): Grind the coating mixture obtained in step (3) using a sand mill for 0.8 hours to obtain the coating base liquid, and control the grinding fineness to be ≤80μm;

[0091] Step (5): Add 0.20 parts of wet sericite powder with an average particle size of 15-20 μm to the coating base liquid obtained in step (4), stir at a speed of 2500 r / min for 25 min, and control the temperature below 40℃ to obtain component A of fast-drying heat-resistant solvent-free epoxy coating.

[0092] Step (6): 0.60 parts of Ancamine 2753 alicyclic amine curing agent and 0.028 parts of K-54 tertiary amine curing accelerator are added to 1 part of SM113 aromatic amine curing agent in sequence. Stir at 1500 r / min for 10 min and control the temperature below 30℃ to obtain component B of fast-drying heat-resistant solvent-free epoxy coating.

[0093] Step (7): Mix component A and component B in a weight ratio of 1:0.20 to obtain the fast-drying, heat-resistant, solvent-free epoxy coating.

[0094] The properties of the fast-drying, heat-resistant, solvent-free epoxy coating prepared in Example 3 were tested, and the properties of the coating and its coating are shown in Table 3.

[0095] Table 3 shows the properties of the fast-drying, heat-resistant, solvent-free epoxy coating prepared in Example 3.

[0096]

[0097]

[0098] Example 4

[0099] Step (1): 0.48 parts of F-53 bisphenol A phenolic epoxy resin and 0.20 parts of SM-80 1,6-hexanediol diglycidyl ether were added to 1 part of SMF-170S bisphenol F epoxy resin in sequence, and stirred at 1600 r / min for 18 min, while controlling the temperature to be below 40℃.

[0100] In step (2), 0.010 parts of TEGO Airex 902W polyether siloxane defoamer, 0.003 parts of TEGODispers 685 polymer dispersant, 0.007 parts of TEGO Glide 450 polyether siloxane copolymer leveling agent, and 0.006 parts of TEGO Wet 270 polyether siloxane copolymer substrate wetting agent are added sequentially to the epoxy resin liquid obtained in step (1). The mixture is stirred at a speed of 1400 r / min for 10 min, and the temperature is controlled to be below 40℃.

[0101] In step (3), 0.020 parts of HQNANO-CNTs-009-4 type carbon nanofibers, 0.02 parts of organic bentonite, 0.50 parts of wollastonite powder, 0.48 parts of rutile titanium dioxide, 0.05 parts of carbon black, 0.36 parts of talc powder and 0.29 parts of barite powder are added sequentially to the resin mixture obtained in step (2), and stirred at a speed of 1600 r / min for 24 min, while controlling the temperature to be below 40℃.

[0102] Step (4): Grind the coating mixture obtained in step (3) using a sand mill for 0.6 hours to obtain the coating base liquid, and control the grinding fineness to be ≤80μm;

[0103] Step (5): Add 0.26 parts of wet sericite powder with an average particle size of 15-20 μm to the coating base liquid obtained in step (4), stir at a speed of 2400 r / min for 25 min, and control the temperature below 40℃ to obtain component A of fast-drying heat-resistant solvent-free epoxy coating.

[0104] Step (6): 0.40 parts of Ancamine 2753 alicyclic amine curing agent and 0.03 parts of K-54 tertiary amine curing accelerator are added to 1 part of SM113 aromatic amine curing agent in sequence. Stir at 1400 r / min for 12 min and control the temperature below 30℃ to obtain component B of fast-drying heat-resistant solvent-free epoxy coating.

[0105] Step (7): Mix component A and component B in a weight ratio of 1:0.23 to obtain the fast-drying, heat-resistant, solvent-free epoxy coating.

[0106] The properties of the fast-drying, heat-resistant, solvent-free epoxy coating prepared in Example 4 were tested, and the properties of the coating and its coating are shown in Table 4.

[0107] Table 4 shows the performance of the fast-drying, heat-resistant, solvent-free epoxy coating prepared in Example 4.

[0108]

[0109] In Comparative Example 1, 0.6 parts of F-53 bisphenol A phenolic epoxy resin and 0.5 parts of SM-80 1,6-hexanediol diglycidyl ether were added sequentially to E-51 bisphenol A epoxy resin and stirred at 1600 r / min for 15 min, while keeping the temperature below 40℃.

[0110] In step (2), 0.030 parts of TEGO Airex 902W polyether siloxane defoamer, 0.009 parts of TEGO Glide450 polyether siloxane copolymer leveling agent, and 0.006 parts of TEGO Wet 270 polyether siloxane copolymer substrate wetting agent are added sequentially to the epoxy resin liquid obtained in step (1), and stirred at a speed of 1400 r / min for 10 min, while controlling the temperature to be below 40℃.

[0111] In step (3), 0.02 parts of organic bentonite, 0.50 parts of wollastonite powder, 0.48 parts of rutile titanium dioxide, 0.05 parts of carbon black, 0.36 parts of talc powder, and 0.29 parts of barite powder are added sequentially to the resin mixture solution obtained in step (2), and stirred at a speed of 1600 r / min for 24 min, while controlling the temperature to be below 40℃.

[0112] Step (4): Grind the coating mixture obtained in step (3) using a sand mill for 0.6 hours to obtain the coating base liquid, and control the grinding fineness to be ≤80μm;

[0113] Step (5): 0.26 parts of wet sericite powder with an average particle size of 15-20 μm are added to the coating base liquid obtained in step (4), and stirred at a speed of 2400 r / min for 25 min, while controlling the temperature to be below 40℃, to obtain component A of the solvent-free epoxy coating.

[0114] Step (6): Add 0.40 parts of EPIKURE F 205 alicyclic amine curing agent to 2 parts of Aradur 5200 aromatic amine curing agent, stir at 1600 r / min for 10 min, and control the temperature below 30℃ to obtain component B of solvent-free epoxy coating;

[0115] Step (7): Mix component A and component B in a weight ratio of 1:0.25 to obtain the solvent-free epoxy coating.

[0116] The relevant properties of the solvent-free epoxy coating prepared in Comparative Example 1 were tested, and the properties of the coating and its coating are shown in Table 5.

[0117] Table 5 shows the properties of the solvent-free epoxy coatings prepared in Comparative Example 1.

[0118]

[0119] It can be seen that in Comparative Example 1, which only used bisphenol A epoxy resin, the drying time increased significantly compared to Example 1, and the bending resistance decreased significantly. This indicates that in the embodiments of the present invention, by using bisphenol A phenolic epoxy resin and bisphenol F epoxy resin as the film-forming resin system, the two hydrogen atoms of bisphenol F epoxy resin replaced the methyl functional group in bisphenol A epoxy resin. In addition to having the basic characteristics of bisphenol A epoxy resin, its viscosity also decreased, thus improving the application performance of the coating.

[0120] Comparative Example 2

[0121] Step (1): 1 part of F-53 bisphenol A phenolic epoxy resin and 0.20 parts of AGE C12-14 alcohol glycidyl ether were added to 1 part of SMF-170S bisphenol F epoxy resin in sequence, and stirred at 2000 r / min for 16 min, while controlling the temperature to be below 40℃.

[0122] In step (2), 0.080 parts of BYK-066N silicone defoamer, 0.003 parts of BYK-P104S dispersant, 0.007 parts of TEGO Glide 450 polyether siloxane copolymer leveling agent, and 0.006 parts of TEGO Wet270 polyether siloxane copolymer substrate wetting agent are added sequentially to the epoxy resin liquid obtained in step (1). The mixture is stirred at 1300 r / min for 15 min, and the temperature is controlled to be below 40℃.

[0123] In step (3), 0.02 parts of organic bentonite, 0.50 parts of wollastonite powder, 0.48 parts of rutile titanium dioxide, 0.07 parts of carbon black, 0.36 parts of talc powder, and 0.29 parts of barite powder are added sequentially to the resin mixture solution obtained in step (2), and stirred at a speed of 1600 r / min for 24 min, while controlling the temperature to be below 40℃.

[0124] Step (4): Grind the coating mixture obtained in step (3) using a sand mill for 0.6 hours to obtain the coating base liquid, and control the grinding fineness to be ≤80μm;

[0125] Step (5): 0.26 parts of wet sericite powder with an average particle size of 15-20 μm are added to the coating base liquid obtained in step (4), and stirred at a speed of 2600 r / min for 20 min, while controlling the temperature to be below 40℃, to obtain component A of the solvent-free epoxy coating.

[0126] Step (6): Add 0.40 parts of Ancamine 2753 alicyclic amine curing agent to 1 part of SM113 aromatic amine curing agent, stir at 1400 r / min for 12 min, and control the temperature below 30℃ to obtain component B of solvent-free epoxy coating;

[0127] Step (7): Mix component A and component B in a weight ratio of 1:0.6 to obtain the solvent-free epoxy coating.

[0128] The relevant properties of the solvent-free epoxy coating prepared in Comparative Example 2 were tested, and the properties of the obtained coating and its coating are shown in Table 6.

[0129] Table 6 shows the properties of the solvent-free epoxy coatings prepared in Comparative Example 2.

[0130]

[0131]

[0132] As can be seen, the high-temperature resistance of Comparative Example 2 is significantly reduced compared with Example 2, which highlights that the addition of carbon nanofibers in this invention greatly improves the good stability of the coating at high temperatures.

[0133] As can be seen from the tables above, the heat-resistant solvent-free epoxy coating in the embodiments of the present invention has excellent heat resistance, high temperature and high pressure resistance and anti-corrosion performance, which shortens the construction cycle of anti-corrosion construction of equipment such as pipelines, storage tanks and pressure vessels in high temperature environments of petrochemical industry (the surface drying time is shortened to 0.4h) and the anti-corrosion effect is well improved.

[0134] In summary, the temperature-resistant solvent-free epoxy coating provided by this invention has the following beneficial effects:

[0135] 1. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention uses bisphenol A phenolic epoxy resin and bisphenol F epoxy resin as the film-forming resin system. Two hydrogen atoms of bisphenol F epoxy resin replace the methyl functional group in bisphenol A epoxy resin. In addition to having the basic characteristics of bisphenol A epoxy resin, its viscosity is reduced, making it suitable for solvent-free coatings. The epoxy group functionality of bisphenol A phenolic epoxy resin is greater than 2, and the crosslinking density is high, which can improve the temperature resistance and corrosion resistance of the coating.

[0136] 2. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention uses aromatic amine curing agent and alicyclic amine curing agent. The molecular structures of aromatic amine and alicyclic amine contain stable benzene ring structure and alicyclic structure, respectively, which improves the heat distortion temperature and thermal decomposition temperature of the coating. At the same time, the two types of curing agents undergo cross-linking reaction with the two types of epoxy resin to form an interpenetrating network, which improves the density, strength and comprehensive anti-corrosion performance of the coating.

[0137] 3. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention uses a tertiary amine curing accelerator. The nitrogen atom of the tertiary amine molecule has a pair of lone pairs of electrons, which can nucleophilically attack the epoxy group and catalyze the self-ring-opening curing of the epoxy resin. This can significantly improve the curing reaction rate of the epoxy resin and shorten the drying and curing time.

[0138] 4. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention uses carbon nanofibers. Carbon fibers have excellent chemical and thermal stability. They can form a uniform heat-transferring network structure inside the coating, reducing cracks caused by local thermal stress concentration inside the coating, thus giving the coating good stability at high temperatures. At the same time, carbon nanofibers are nanoscale materials with volume and surface effects, which greatly enhance the bonding strength of unsaturated bonds between the coating and the protected metal, improving the coating's adhesion and overall anti-corrosion performance.

[0139] 5. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention has good physical properties and anti-corrosion properties, adhesion ≥18MPa, heat resistance (200℃, 300h) with the coating intact, high temperature and high pressure resistance (5% NaCl aqueous solution, 120℃, 10MPa) with the coating intact for 1000h, cathodic disbondment resistance (65℃, -1.5v, 48h) ≤5mm, and salt spray resistance with the coating intact for 3000h.

[0140] 6. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention has the characteristics of fast drying and curing speed. At 25℃, the surface drying time of the coating is ≤0.5h, the actual drying time is ≤2h, and the curing time of the coating is ≤3d.

[0141] 7. The heat-resistant solvent-free epoxy coating provided in this embodiment of the invention is suitable for internal and external corrosion protection of petrochemical pipelines, storage tanks and pressure vessels and other equipment at temperatures below 120℃. It can achieve rapid drying and curing, shortening the construction cycle.

[0142] Finally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0143] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the invention.

[0144] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A heat-resistant solvent-free epoxy coating, characterized in that, The product comprises component A and component B, with a weight ratio of 1:0.18~0.

23. Component A comprises the following components in parts by weight: 1 part bisphenol F epoxy resin, 0.4~0.5 parts phenolic epoxy resin, 0.2~0.4 parts reactive diluent, 0.2~0.3 parts sericite powder, 0.02~0.03 parts carbon nanofiber, 1.4~1.7 parts pigments and fillers, 0.010~0.015 parts defoamer, 0.003~0.006 parts dispersant, 0.005~0.010 parts leveling agent, and 0.006~0.009 parts substrate wetting agent. Component B comprises the following components in parts by weight: 1 part aromatic amine curing agent, 0.4~0.6 parts alicyclic amine curing agent, and 0.02~0.03 parts tertiary amine curing accelerator.

2. The heat-resistant solvent-free epoxy coating according to claim 1, characterized in that, Component A comprises the following components in parts by weight: 1 part bisphenol F epoxy resin, 0.43 parts phenolic epoxy resin, 0.28 parts reactive diluent, 0.25 parts sericite powder, 0.023 parts carbon nanofiber, 1.6 parts pigments and fillers, 0.012 parts defoamer, 0.005 parts dispersant, 0.008 parts leveling agent, and 0.008 parts substrate wetting agent; Component B comprises the following components in parts by weight: 1 part aromatic amine curing agent, 0.5 parts alicyclic amine curing agent, and 0.025 parts tertiary amine curing accelerator.

3. The heat-resistant solvent-free epoxy coating according to claim 1, characterized in that, The bisphenol F epoxy resin is SMF-170S bisphenol F epoxy resin, the phenolic epoxy resin is F-53 bisphenol A phenolic epoxy resin, and the reactive diluent is SM-80 1,6-hexanediol diglycidyl ether.

4. The heat-resistant solvent-free epoxy coating according to claim 1, characterized in that, The sericite powder is wet-processed sericite powder with an average particle size of 15~20μm and a thickness of <5μm; and / or the carbon nanofibers are HQNANO-CNTs-009-4 type carbon nanofibers.

5. The heat-resistant solvent-free epoxy coating according to claim 1, characterized in that, The pigments and fillers comprise the following components in parts by weight: 0.01-0.04 parts of organobentonite, 0.55-0.60 parts of wollastonite powder, 0.37-0.45 parts of rutile titanium dioxide, 0.04-0.07 parts of carbon black, 0.25-0.30 parts of talc powder, and 0.18-0.24 parts of barite powder.

6. The heat-resistant solvent-free epoxy coating according to claim 1, characterized in that, The defoaming The defoamer is at least one of TEGO Airex 902W polyether silicone defoamer, Efka EFKA-2010 non-organosilicone defoamer, and BYK-066N organosilicone defoamer; and / or the dispersant is at least one of TEGO Dispers 685 polymer dispersant, BYK-P104S dispersant, and Dow PPOLYOX TMWSR N-60K polyethylene oxide dispersant; and / or the leveling agent is at least one of TEGO Glide 450 polyether silicone copolymer leveling agent, TEGO Glide 410 polyether silicone copolymer leveling agent, and BYK-333 polyether modified silicone leveling agent; and / or the substrate wetting agent is at least one of TEGO Wet 270 polyether silicone copolymer substrate wetting agent, TEGO Wet 280 polyether silicone copolymer substrate wetting agent, and BYK-346 polyether silicone copolymer wetting agent.

7. The heat-resistant solvent-free epoxy coating according to claim 1, characterized in that, The aromatic amine curing agent is at least one of SM113 aromatic amine curing agent, Aradur 5200 aromatic amine curing agent, and BD10 modified aromatic amine curing agent; the alicyclic amine curing agent is at least one of Ancamine 2753 alicyclic amine curing agent, EPIKURE F 205 alicyclic amine curing agent, and WSG-322 modified alicyclic amine curing agent; the tertiary amine curing accelerator is at least one of K-54 tertiary amine curing accelerator and DMP-30 tertiary amine curing accelerator.

8. A method for preparing a heat-resistant solvent-free epoxy coating as described in any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Add phenolic epoxy resin and reactive diluent to bisphenol F epoxy resin in sequence, stir once to disperse the components evenly, and cool to room temperature to obtain epoxy resin liquid. Step 2: Add the defoamer, dispersant, leveling agent and substrate wetting agent to the above epoxy resin liquid, and stir twice to make the components evenly dispersed to obtain an epoxy resin mixed solution. Step 3: Add carbon nanofibers and pigments / fillers to the resin mixture solution in sequence, and stir three times to ensure that the components are evenly dispersed to obtain the coating mixture; Step 4: Grind the coating mixture obtained in Step 3 to obtain the coating base liquid, wherein the grinding fineness is ≤80μm; Step 5: Add sericite powder to the coating base liquid obtained in Step 4, and stir four times to ensure that the components are evenly dispersed, thus obtaining component A of the heat-resistant solvent-free epoxy coating. Step 6: Add the cycloaliphatic amine curing agent and the tertiary amine curing accelerator to the aromatic amine curing agent in sequence, and stir five times to ensure that the components are evenly dispersed, so as to obtain component B of the heat-resistant solvent-free epoxy coating. Step 7: Mix component A and component B evenly according to the weight ratio of the two components to obtain the heat-resistant solvent-free epoxy coating.

9. The method for preparing solvent-free epoxy coating according to claim 8, characterized in that, The temperature of the first stirring is 10℃-40℃, the stirring speed is 1500-2000 r / min, and the stirring time is 15-20 min; and / or the temperature of the second stirring is 10℃-40℃, the stirring speed is 1000-1500 r / min, and the stirring time is 10-15 min; the temperature of the third stirring is 10℃-40℃, the stirring speed is 1500-2000 r / min, and the stirring time is 20-25 min; the temperature of the fourth stirring is 10℃-40℃, the stirring speed is 2000-2500 r / min, and the stirring time is 25-30 min; the temperature of the fifth stirring is 10℃-30℃, the stirring speed is 1000-1500 r / min, and the stirring time is 10-15 min.

10. The application of the heat-resistant solvent-free epoxy coating according to any one of claims 1-7 in the internal and external corrosion protection of petrochemical equipment at temperatures below 120°C.

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