Bi-component epoxy coating, wire winding, preparation method of wire winding and electric reactor

Abstract

The invention relates to a bi-component epoxy coating, a wire winding, a preparation method of the wire winding and an electric reactor. The bi-component epoxy coating comprises an epoxy prepolymer, an epoxy curing agent and a self-repairing microcapsule, wherein the self-repairing microcapsule contains an epoxy microcapsule and an amine microcapsule; wherein the amine microcapsule and the capsule wall of the epoxy microcapsule comprise polyurea, so that core liquid of the epoxy microcapsule and the amine microcapsule can be effectively preserved during primary thermocuring, and is not easy to flow out in advance. When the coating has cracks, bisphenol F diglycidyl ether in the amine microcapsules and aliphatic polyamine in the epoxy microcapsules can flow out and are gradually mixed, due to the high reaction activity of the aliphatic polyamine, secondary curing can be achieved without high temperature, microcracks can be repaired, further spreading of defects is prevented, and the service life of the coating is prolonged. And the long-term service capability of the self-repairing resin layer is effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of multifunctional coating, in particular to a two-component epoxy coating, a wire winding and a preparation method thereof, and a reactor. BACKGROUND

[0002] The epoxy coating has good adhesion and insulation capacity, and can electrically isolate the wire from other components as the surface coating of the wire winding of the reactor, thereby preventing short circuit, electric leakage and partial discharge to ensure electrical insulation, and also isolating moisture, dust and corrosive substances to avoid wire oxidation and corrosion, thereby prolonging the service life of the equipment.

[0003] However, the service environment of the reactor is harsh, and the surface coating thereof needs to face the combined influence of mechanical vibration, thermal stress, ultraviolet radiation and other factors. The traditional epoxy coating is difficult to cope with the service environment of the reactor for a long time, and small cracks will gradually appear on the surface and gradually develop from the surface to the inside, so that moisture, humidity and other substances will invade the inside of the reactor, causing inter-turn discharge and even discharge ablation and burning of the coil. SUMMARY

[0004] Therefore, it is necessary to provide a two-component epoxy coating capable of imparting self-repairing ability to the coating, to improve the long-term service ability of the obtained epoxy coating in the harsh service environment of the reactor, and further to provide a wire winding and a preparation method thereof, and a reactor with the wire winding.

[0005] In a first aspect, the present application provides a two-component epoxy coating.

[0006] The two-component epoxy coating comprises an epoxy resin composition and an epoxy curing agent, the epoxy resin composition comprises an epoxy prepolymer and self-repairing microcapsules.

[0007] The self-repairing microcapsules comprise epoxy microcapsules and amine microcapsules, the core liquid of the epoxy microcapsules comprises bisphenol F diglycidyl ether, and the core liquid of the amine microcapsules comprises polyether polyamine, and the capsule wall of the amine microcapsules and the epoxy microcapsules comprises polyurea.

[0008] In some embodiments, the two-component epoxy coating comprises, in mass fraction:

[0009] The epoxy prepolymer is 90-110 parts;

[0010] The epoxy curing agent is 10-20 parts; and

[0011] The self-repairing microcapsules are 1-15 parts.

[0012] In some embodiments, the average particle size of the epoxy microcapsules is 50-100 μm; and / or

[0013] The average particle size of the amine microcapsule is 50-100 μm.

[0014] In some embodiments, the core liquid of the epoxy microcapsule further comprises an epoxy diluent.

[0015] In some embodiments, the core liquid of the amine microcapsule further comprises an aliphatic polyamine.

[0016] In some embodiments, the epoxy curing agent comprises one or more of an imidazole epoxy curing agent and an acid anhydride epoxy curing agent.

[0017] In some embodiments, the mass ratio of the epoxy microcapsule and the amine microcapsule is (1-1.5):1.

[0018] In a second aspect, the application provides a wire winding.

[0019] A wire winding comprises a wire and a self-repairing resin layer on at least a part of the surface of the wire; the self-repairing resin layer comprises an epoxy resin layer formed by the two-component epoxy coating described above.

[0020] In a third aspect, the application provides a method for preparing the wire winding described above.

[0021] A method for preparing the wire winding described above comprises the following steps:

[0022] The fiber bundle is impregnated with the two-component epoxy coating and wound to form a wet winding;

[0023] The two-component epoxy coating on the surface of the wet winding is cured to form an epoxy self-repairing resin coating at a temperature of 80-150℃ in a stepwise manner.

[0024] In a fourth aspect, the application provides a reactor. The reactor has the wire winding described above.

[0025] The two-component epoxy coating described above is added with self-repairing microcapsules to endow the coating with self-repairing ability. The capsule walls of the epoxy microcapsule and the amine microcapsule comprise polyurea with good heat resistance, which can effectively preserve the core liquid of the epoxy microcapsule and the amine microcapsule during thermal curing and prevent them from flowing out prematurely. When a crack appears in the coating, the bisphenol F diglycidyl ether in the epoxy microcapsule and the polyether polyamine in the amine microcapsule will flow out and gradually mix. Due to the high reactivity of the polyether polyamine, curing and repairing of microcracks can be achieved without high temperature, which prevents the defects from further spreading and helps to improve the long-term service ability of the self-repairing resin layer. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of these drawings.

[0027] Figure 1 The flow chart for preparing the winding of the reactor by the wet vertical winding method.

[0028] Figure 2 The SEM image of the epoxy microcapsule in an embodiment of the present application. Wherein, (a) is the SEM image of the epoxy microcapsule prepared in Example 1; Figure 2 (b) is the shell-core structure of the epoxy microcapsule prepared in Example 1; Figure 2 (c) is the SEM image of the amine microcapsule prepared in Example 1; Figure 2 (d) is the shell-core structure of the amine microcapsule prepared in Example 1.

[0029] Figure 3 The SEM image of the cross section of the reactor prepared in Comparative Example 1 of the present application after being destroyed.

[0030] Figure 4 The SEM image of the cross section of the self-repairing reactor prepared in Example 1 of the present application after being cleaned with toluene immediately after being destroyed.

[0031] Figure 5 The SEM image of the cross section of the self-repairing reactor prepared in Example 1 of the present application after being destroyed and self-repairing for 48 h at 25℃.

[0032] Figure 6 The force-displacement curve of the self-repairing composite WTDCB sample containing the self-repairing microcapsule in Example 1 of the present application after being pulled apart for the first time and being repaired at room temperature for 48 h and then being pulled apart again.

[0033] Reference signs

[0034] 100, conductor; 200, wet winding; 300, two-component epoxy coating. DETAILED DESCRIPTION

[0035] In order to make the above purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail. In the following description, a lot of specific details are set forth in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0036] In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified. In the present application, the meaning of "at least one" is one or more, such as one, two, and more than two. The meaning of "a plurality of" or "several" is at least two, such as two, three, etc.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0038] When a numerical range is disclosed herein, the range is to be construed as having been recited to the full extent of the range, including every value within the range and every sub-range between values within the range. Further, when a range is provided, it is intended to include the endpoints of the range and every value within the range. In addition, it is intended that when a plurality of ranges are provided, the ranges can be combined and the description shall apply to those sub-ranges as well.

[0039] If not specifically stated, all steps of the present application can be carried out in sequence or randomly. For example, the method comprises steps (a) and (b), which means that the method can comprise steps (a) and (b) in sequence, or steps (b) and (a) in sequence. For example, the method also comprises step (c), which means that step (c) can be added to the method in any order, for example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0040] In the present application, "above" or "below" includes the present number. For example, 1 below includes 1.

[0041] In the present application, the temperature parameter, unless otherwise specified, allows for constant temperature treatment, and also allows for fluctuations within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within a range such as ±5°C, ±4°C, ±3°C, ±2°C, ±1°C are allowed.

[0042] The epoxy coating has good adhesion and insulation capacity, and can electrically isolate the conductor winding from other components as the surface coating of the reactor conductor winding, thereby preventing short circuit, electric leakage and partial discharge to ensure electrical insulation, and also isolating moisture, dust and corrosive substances to avoid oxidation and corrosion of the conductor, thereby prolonging the service life of the equipment.

[0043] However, the service environment of the reactor is harsh, and the surface coating needs to face the combined effects of mechanical vibration, thermal stress, ultraviolet radiation and other factors. The traditional epoxy coating is difficult to cope with the service environment of the reactor for a long time. Micro cracks will gradually appear on the surface of the traditional epoxy coating, and gradually develop from the surface to the inside. Moisture, humidity and other substances will invade the inside of the reactor, causing inter-turn discharge, even discharge ablation, and burning the coil.

[0044] Therefore, the first aspect of the present application provides a two-component epoxy coating capable of imparting certain self-repairing ability to the obtained coating.

[0045] For example, the two-component epoxy coating includes an epoxy resin composition and an epoxy curing agent. The epoxy resin composition includes an epoxy prepolymer and self-repairing microcapsules. The self-repairing microcapsules include epoxy microcapsules and amine microcapsules. The core liquid of the epoxy microcapsules includes bisphenol F diglycidyl ether, and the core liquid of the amine microcapsules includes polyether polyamine. The capsule wall of the amine microcapsules and the epoxy microcapsules includes polyurea.

[0046] The two-component epoxy coating described above adds self-repairing microcapsules to impart certain self-repairing ability to the coating. The capsule wall of the epoxy microcapsules and the amine microcapsules includes polyurea with good heat resistance, which can effectively preserve the core liquid of the epoxy microcapsules and the amine microcapsules during initial thermal curing, and prevent them from flowing out too early. After the resin layer cracks, the bisphenol F diglycidyl ether in the epoxy microcapsules and the polyether polyamine in the amine microcapsules will flow out and gradually mix. Due to the high thermal stability and reactivity of the polyether polyamine, it can withstand the high temperature of the reactor curing process and solidify at room temperature. By repairing micro-cracks to prevent further spread of defects, the long-term service ability of the epoxy self-repairing resin layer is effectively improved.

[0047] In some embodiments, the polyether polyamine includes JEFFAMINE T403. The polyether polyamine JEEFAMINET403 has moderate molecular weight, and has both high thermal stability and room temperature curing activity. Other polyether polyamines of the same type, such as JEFFAMINE D200, have high room temperature activity but low thermal stability, and volatilize during the long heating process of the reactor, and thus cannot achieve self-repairing function; and JEFFAMINE T5000 has excellent thermal stability but very low room temperature activity, and thus cannot be cured at room temperature and is difficult to have self-repairing function.

[0048] In some embodiments, the epoxy curing agent includes one or more of imidazole epoxy curing agents and anhydride epoxy curing agents. The imidazole epoxy curing agents and the anhydride epoxy curing agents can impart better thermal stability to the self-repairing resin layer, and are commonly used curing agents in the service environment of the reactor. However, at the same time, such curing agents can easily lead to a decrease in the toughness of the coating and more easily cause cracking. In this regard, the self-repairing ability of the two-component epoxy coating described above can well compensate for this defect, so that the obtained resin layer has both good thermal stability and excellent long-term service ability.

[0049] In some embodiments, the epoxy prepolymer includes one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol S type epoxy resin.

[0050] In some embodiments, the two-component epoxy coating includes, in terms of mass fraction:

[0051] 90-110 parts of epoxy prepolymer;

[0052] 10-20 parts of epoxy curing agent; and

[0053] 1-15 parts of self-repairing microcapsules.

[0054] Optionally, the mass fraction of the epoxy prepolymer can be, but is not limited to, 90 parts, 95 parts, 100 parts, 105 parts, 110 parts, or other values within the range of 90-110 parts.

[0055] Optionally, the mass fraction of the epoxy curing agent can be, but is not limited to, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, or other values within the range of 10-20 parts.

[0056] Optionally, the mass fraction of the self-repairing microcapsules can be, but is not limited to, 1 part, 3 parts, 5 parts, 7 parts, 9 parts, 11 parts, 13 parts, 15 parts, or other values within the range of 1-15 parts.

[0057] In some embodiments, the content of the self-repairing microcapsules is 4% to 6% by mass percentage of the two-component epoxy coating. The content of the self-repairing microcapsules should not be too high, otherwise the microcapsules will aggregate due to the high concentration, which will adversely affect the material performance.

[0058] In some embodiments, the average particle size of the epoxy microcapsules is 50 μm to 100 μm. Further, the average particle size of the epoxy microcapsules is 50 μm to 75 μm.

[0059] In some embodiments, the average particle size of the amine microcapsules is 50 μm to 100 μm. Further, the average particle size of the amine microcapsules is 50 μm to 75 μm.

[0060] It has been found through research that keeping the particle size of the epoxy microcapsules and the amine microcapsules within the above range can improve the wettability of the fiber bundles, which helps to form a more uniform self-repairing resin layer on the surface of the fiber bundles of the reactor, and reduces the fault phenomenon.

[0061] In some embodiments, the core liquid of the epoxy microcapsules further comprises an epoxy diluent. Optionally, the epoxy diluent comprises one or more of n-butyl glycidyl ether, o-tolyl glycidyl ether, and dodecyl glycidyl ether (AGE).

[0062] In some embodiments, the mass ratio of the bisphenol F diglycidyl ether to the epoxy diluent in the core liquid of the epoxy microcapsules is 10:(1-3). Optionally, the mass ratio of the bisphenol F diglycidyl ether to the epoxy diluent can be, but is not limited to, 10:1, 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 10:3, or other values within the range of 10:(1-3). When preparing epoxy microcapsules with smaller particle sizes, it is necessary to keep the core liquid viscosity low, and if the viscosity is reduced by using an epoxy diluent, the epoxy group content in the core liquid will be diluted, which is not conducive to maintaining the self-repairing performance. By selecting bisphenol F diglycidyl ether and matching the epoxy diluent in the above ratio, compared with the traditional bisphenol A diglycidyl ether formula, the number of epoxy groups in the core liquid can be effectively increased on the premise of obtaining epoxy microcapsules with the target particle size, thereby effectively improving the self-repairing ability of the coating with less addition of epoxy microcapsules.

[0063] In some embodiments, the core liquid of the amine microcapsules further comprises an aliphatic polyamine.

[0064] In some embodiments, the aliphatic polyamine comprises one or more of triethylenetetramine and tetraethylenepentamine. Aliphatic polyamines generally have good activity and can be well cross-linked with epoxy resins in non-high-temperature environments.

[0065] In some embodiments, the mass ratio of the aliphatic polyamine to the polyether polyamine in the core liquid of the amine microcapsule is 20:(1-4). Alternatively, the mass ratio of the aliphatic polyamine to the polyether polyamine can be, but is not limited to, 20:1, 15:1, 10:1, 8:1, 20:3, 6:1, 5:1, or other values within the range of 20:(1-4).

[0066] In some embodiments, the mass ratio of the epoxy microcapsule to the amine microcapsule is (1-1.5):1. Alternatively, the mass ratio of the epoxy microcapsule to the amine microcapsule can be, but is not limited to, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, or other values within the range of (1-1.5):1. It has been found that the self-repairing resin layer with good mechanical properties can be obtained by using the above-mentioned ratio.

[0067] In some embodiments, the self-repairing microcapsule is prepared by using the electrostatic spraying-interfacial polymerization microencapsulation technology.

[0068] In some embodiments, the method for preparing the epoxy microcapsule comprises:

[0069] Mixing the core liquid of the epoxy microcapsule with the shell-forming monomer to obtain a first to-be-coated liquid;

[0070] Extruding the first to-be-coated liquid at a rate of 4 mL / h-6 mL / h and atomizing it under an electrostatic voltage of 21 kV-23 kV to form first microdroplets;

[0071] Receiving the first microdroplets using a first mixed solution to form first nascent microcapsules, wherein the first mixed solution comprises water, a surfactant, and a shell-forming reagent;

[0072] Reacting at 80°C-100°C for 6 h-14 h to obtain the epoxy microcapsule.

[0073] It can be understood that the polyether is synthesized by reacting an isocyanate component with an amino compound component.

[0074] In some embodiments, the shell-forming monomer comprises 4,4-dicyclohexyl methane diisocyanate.

[0075] In some embodiments, the surfactant comprises sodium dodecyl sulfonate.

[0076] In some embodiments, the shell-forming reagent comprises diethylene triamine.

[0077] In some embodiments, the mass concentration of the shell-forming reagent in the first mixed solution is 10%-15%.

[0078] In some embodiments, the mass concentration of the surfactant in the first mixed solution is 0.5% to 3%.

[0079] In some embodiments, the mixed mass ratio of the core liquid of the epoxy microcapsule to 4,4-dicyclohexyl methane diisocyanate is 95:(3 to 8).

[0080] In some embodiments, the method for preparing the amine microcapsule comprises:

[0081] The core liquid of the amine microcapsule is used as the second liquid to be coated;

[0082] The second liquid to be coated is extruded at a rate of 5 mL / h to 7 mL / h and atomized under an electrostatic voltage of 19 kV to 21 kV to form second microdroplets;

[0083] The second microdroplets are received by using a second mixed solution to obtain second nascent microcapsules, wherein the second mixed solution comprises n-hexadecane, decaline, a surfactant, a shell-forming monomer, and a shell-forming reagent.

[0084] The reaction is carried out at 70°C to 90°C for 2 h to 4 h to obtain the amine microcapsule.

[0085] In some embodiments, the mass concentration of the shell-forming reagent in the second mixed solution is 0.05% to 0.3%.

[0086] In some embodiments, the mass concentration of the shell-forming monomer in the second mixed solution is 8% to 15%.

[0087] In some embodiments, the mass concentration of the surfactant in the second mixed solution is 0.5% to 3%.

[0088] In a second aspect, the present application provides a wire winding.

[0089] The wire winding comprises a wire and a self-repairing resin layer on at least a part of the surface of the wire; wherein the self-repairing epoxy resin layer comprises an epoxy resin layer formed by the two-component epoxy coating described above. It should be noted that the wire winding of the present application is obtained by a wet vertical winding method, that is, when winding, the resin coating on the surface of the wire has not been cured, and the wires can be pressed against each other to make contact, so that the final wire winding does not necessarily have an epoxy resin layer on all surfaces. Alternatively, the thickness of the epoxy resin layer on the surface of the wire winding is 0 to 5 mm.

[0090] In some embodiments, the wire comprises a fiber bundle or a fiber tape.

[0091] In a third aspect, the present application provides a method for preparing the wire winding described above.

[0092] In some embodiments, the method for preparing the wire winding includes:

[0093] immersing the fiber bundle in the two-component epoxy coating, and winding to form a wet winding;

[0094] curing the two-component epoxy coating to form a self-repairing resin layer by stepwise heating at 80-150°C.

[0095] In some embodiments, the step of stepwise heating at 80-150°C includes:

[0096] curing at 80-110°C for 1-3h;

[0097] curing at 110-130°C for 2-6h;

[0098] curing at 130-150°C for 4-6h.

[0099] The stepwise heating can make the coating curing more uniform, and effectively reduce the problem of solvent release being blocked due to rapid surface curing.

[0100] In some embodiments, the wire winding of the electric reactor is prepared by the wet vertical winding method. For example, see Figure 1 , Figure 1 Figure 1 is a flow diagram of the wet vertical winding method for preparing the wire winding of the electric reactor. The wire 100 is pulled through the immersion tank containing the two-component epoxy coating 300, so that the surface of the wire 100 is immersed in the two-component epoxy coating 300, and further wound to form a wet winding 200, which is heat-cured to form the wire winding.

[0101] In a fourth aspect, the present application provides an electric reactor having the above wire winding.

[0102] The present application will be further described in detail below with reference to specific examples.

[0103] In the following specific examples and comparative examples, the raw materials used, unless otherwise specified, are commercially available; the instruments used, unless otherwise specified, are commercially available; and the processes used, unless otherwise specified, are routinely selected by those skilled in the art.

[0104] Example 1

[0105] This example provides a two-component epoxy coating.

[0106] The preparation method of the two-component epoxy coating of this example is as follows:

[0107] 8370 g of epoxy resin monomer GELR-128 is mixed with 1130 g of imidazole curing agent QS-812, 25 g of epoxy microcapsules and 25 g of amine microcapsules are added, and after uniform dispersion, a two-component epoxy coating is obtained.

[0108] The preparation method of the epoxy microcapsules is as follows:

[0109] 90 g of bisphenol F bisglycidyl ether (BFDGE) is mixed with 10 g of epoxy diluent n-butyl glycidyl ether (BGE) to form F10B epoxy resin;

[0110] 95 g of F10B epoxy resin is mixed with 5 g of 4,4-dicyclohexyl methane diisocyanate (HMDI) to form a first to-be-coated liquid;

[0111] The first to-be-coated liquid is loaded into a syringe and extruded at a rate of 5.0 mL / h, and atomized under an electrostatic voltage of 22 kV to form first microdroplets;

[0112] The first microdroplets are received by using a first mixed solution containing 100.0 mL of deionized water, 1.0 g of sodium dodecyl sulfonate, and 12.0 g of diethylene triamine to form first primary microcapsules;

[0113] After reaction at 90°C for 10 h, water washing, filtration, and room temperature drying, epoxy microcapsules are obtained.

[0114] Please refer to Figure 2 , Figure 2 (a) is the SEM image of the epoxy microcapsules prepared in this embodiment, and the particle size of the epoxy microcapsules is 40 μm-60 μm. Figure 2 (b) is the shell-core structure of the epoxy microcapsules prepared in this embodiment, and the capsule wall is thin and dense, with a thickness of 1 μm-1.5 μm.

[0115] The preparation method of the amine microcapsules is as follows:

[0116] 15 g of tetraethylenepentamine (TEPA) is mixed with 85 g of polyether polyamine JEFFAMINE T403 to form a second to-be-coated liquid;

[0117] The second to-be-coated liquid is loaded into a syringe and extruded at a rate of 6.0 mL / h, and atomized under an electrostatic voltage of 20 kV to form core liquid microdroplets.

[0118] The core liquid microdroplets are received by using a second mixed solution to form second primary microcapsules containing amine curing agents. The second mixed solution contains 75 mL of n-hexadecane, 75 mL of decahydronaphthalene, 2.0 wt% of surfactant Arlacel P135, 0.1 wt% of diethylene triamine, and 18 g of shell-forming monomer HMDI.

[0119] After reaction at 80℃ for 3h, cleaning with cyclohexane, filtration and drying at room temperature, the amine microcapsules were obtained.

[0120] Referring to Figure 2 , Figure 2 (c) is the SEM image of the epoxy microcapsules prepared in this example, and the particle size of the amine microcapsules is 40μm~60μm. Figure 2 (d) is the shell-core structure of the amine microcapsules prepared in this example, and the outer wall of the capsule wall is rough, the inner wall is thin and dense, and the total thickness is about 1.8μm~2.3μm.

[0121] Example 2

[0122] This example provides a wire winding.

[0123] Referring to Figure 1 , the preparation method of the wire winding of this example is as follows:

[0124] The fiber bundle is pulled and passed through the infiltration pool containing the two-component epoxy coating of Example 1, so that the two-component epoxy coating fully infiltrates the surface of the fiber bundle, and then is wound on the reactor, and is cured in a heat press tank by stepwise temperature rising to obtain a wire winding with a self-repairing resin layer on the surface.

[0125] The step of stepwise temperature rising curing is as follows:

[0126] Curing at 100℃ for 2h;

[0127] Curing at 120℃ for 4h;

[0128] Curing at 140℃ for 5h.

[0129] Comparative Example 1

[0130] This comparative example provides a common wire winding.

[0131] The preparation method of the common wire winding of this comparative example is basically the same as that of Example 2, except that:

[0132] The two-component epoxy coating in the infiltration pool is mixed by an epoxy resin monomer and an imidazole curing agent, and the mixing mass ratio is 100:13.5.

[0133] Figure 4 The SEM image of the fracture surface of the self-repairing reactor prepared in Example 1 of this application after being destroyed and immediately cleaned with toluene. Since the self-repairing microcapsules are washed away after being released, both the self-repairing microcapsules and the resin matrix on the fracture surface can be seen, but no self-repairing curing product is seen. Figure 5The SEM image of the cross section of the self-healing reactor prepared in Example 1 of the present application after being broken and self-healing at 25℃ for 48h. The solidified product of the microcapsule core liquid has appeared on the cross section, showing good self-healing ability.

[0134] A self-healing composite WTDCB (width-tapered double canti-lever beam) sample containing 5wt% self-healing microcapsules (Example 1) was prepared by layering process, and the self-healing ability of the self-healing microcapsules was further verified. Figure 6 The force-displacement curve of the self-healing composite WTDCB sample containing the self-healing microcapsules of Example 1 of the present application after being broken for the first time and then being repaired at room temperature for 48h and then being broken again. According to the sample configuration, the repair efficiency of the self-healing sample based on the fracture toughness is the ratio of the peak value of the force-displacement curve when broken again to the peak value of the force-displacement curve when broken for the first time, i.e. the average self-repairing efficiency of the self-healing sample is 83%, indicating that the self-healing microcapsules exhibit good self-healing ability, which is consistent with the test results of Figure 5 .

[0135] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, all possible combinations of the technical features in the above-described embodiments are not described, however, as long as the combinations of the technical features do not contradict each other, they should be considered within the scope of the present disclosure.

[0136] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled persons in the art, some modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims, and the description can be used to explain the content of the claims.

Claims

1. A two-component epoxy coating, characterized in that, The two-component epoxy coating comprises an epoxy resin composition and an epoxy curing agent, the epoxy resin composition comprises an epoxy prepolymer and self-repairing microcapsules; The self-repairing microcapsules comprise epoxy microcapsules and amine microcapsules, the core liquid of the epoxy microcapsules comprises bisphenol F diglycidyl ether, the core liquid of the amine microcapsules comprises polyether polyamine, and the capsule wall of the amine microcapsules and the epoxy microcapsules comprises polyurea.

2. The two-component epoxy coating according to claim 1, characterized in that, The two-component epoxy coating comprises, in mass fraction: The epoxy prepolymer is 90-110 parts; The epoxy curing agent is 10-20 parts; and The self-repairing microcapsules are 1-15 parts.

3. The two-component epoxy coating according to claim 1, characterized in that, The average particle size of the epoxy microcapsules is 50-100 μm; and / or The average particle size of the amine microcapsules is 50-100 μm.

4. The two-component epoxy coating of claim 1, wherein, The core liquid of the epoxy microcapsules further comprises an epoxy diluent.

5. The two-component epoxy coating of claim 1, wherein, The core liquid of the amine microcapsules further comprises an aliphatic polyamine.

6. The two-component epoxy coating according to any one of claims 1 to 5, characterized in that The epoxy curing agent comprises one or more of imidazole epoxy curing agents and acid anhydride epoxy curing agents.

7. The two-component epoxy coating according to any one of claims 1 to 5, characterized in that The mass ratio of the epoxy microcapsules to the amine microcapsules is (1-1.5):

1.

8. A wire winding, characterized by The lead wire is provided with a self-repairing resin layer on at least a part of the surface of the lead wire, and the self-repairing resin layer comprises an epoxy resin layer formed by the two-component epoxy coating according to any one of claims 1-7.

9. A method of manufacturing a wire winding as claimed in claim 8, characterized in that The method comprises the following steps: The fiber bundle is impregnated with the two-component epoxy coating and wound to form a wet winding; The two-component epoxy coating on the surface of the wet winding is cured to form a self-repairing resin layer by stepwise heating at 80-150°C.

10. A reactor, characterized by The electric reactor has the lead wire winding according to claim 8.

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