CN110117450B

CN110117450B - Coating system, anticorrosion and heat conduction integrated coating, and preparation method and application thereof

Info

Publication number: CN110117450B
Application number: CN201910490884.6A
Authority: CN
Inventors: 周开河; 王立平; 曹文杰; 卢光明; 周奇波; 杨跃平; 刘栓; 郭小平; 蒲吉斌
Original assignee: Yongyao Science And Technology Branch Of Ningbo Transmission And Transfer Construction Co ltd; Ningbo Institute of Material Technology and Engineering of CAS
Current assignee: Yongyao Science And Technology Branch Of Ningbo Transmission And Transfer Construction Co ltd; Ningbo Institute of Material Technology and Engineering of CAS
Priority date: 2019-06-06
Filing date: 2019-06-06
Publication date: 2021-04-30
Anticipated expiration: 2039-06-06
Also published as: CN110117450A

Abstract

The invention discloses a coating system for forming an anticorrosion heat-conducting integrated coating, which comprises a primer and/or a finish, wherein the primer and the finish comprise a curable resin, a high heat-conducting filler, an auxiliary agent and a dispersing agent, and the dispersing agent is derived from a bio-based monomer and has two or more functional groups of carboxyl, hydroxyl and carbonyl. The coating system is divided into a primer and a finish, the bio-based dispersing agent and the high-thermal-conductivity filler are doped in the coating system, the used key raw materials have the characteristics of low price, high thermal conductivity, environmental friendliness, good weather resistance and excellent comprehensive performance, and the coating system has good corrosion resistance and also has high thermal conductivity. Meanwhile, the preparation method is simple, easy to implement, good in controllability and strong in operability, is beneficial to reducing the production cost of industrial production, is beneficial to industrial production, and has wide application prospect.

Description

Coating system, anticorrosion and heat conduction integrated coating, and preparation method and application thereof

Technical Field

The invention belongs to the field of multifunctional protective materials, and particularly relates to a coating system, an anticorrosion heat-conducting integrated coating, a preparation method and related applications thereof.

Background

The transformer is a device for transmitting electric energy or electric signals by utilizing the principle of electromagnetic induction, has the functions of voltage transformation, current transformation and impedance transformation, is an important electric facility in the process of electric power transmission, runs safely and is a basic guarantee for normal running of social life. The transformer is used as an important component of the power transmission network, so that the application environment of the transformer is variable, and a huge development space is provided for future economic development of national grid companies. However, the safe and stable operation of the transformer equipment is greatly tested from the high-humidity and high-heat environment of the ocean to the high-heat environment of the desert. Considering that the working temperature of the transformer exceeds 100 ℃ throughout the year, the anticorrosive paint for the outer wall of the transformer is required to have both anticorrosive performance and heat-conducting performance. The levels of the anti-corrosion heat dissipation coatings produced by various enterprises in China are different at present, although the chemical industry standard of 'anti-corrosion coatings for power transformers' with the standard number of 48606-2015 is released by the national department of industry and informatization in 12 months in 2014, the industry still has market competition at the cost of sacrificing safety and quality.

At present, the anticorrosion paint adopted on the transformer is mainly alkyd paint and chlorinated rubber, the common anticorrosion paint can be used for about 5 years in the environment with the corrosion grade below C3, the acrylic polyurethane paint with better performance can ensure the protection life of about 10 years, but the performance of the common anticorrosion paint in the environment with the corrosion grade above C3, particularly in chemical pollution areas and marine environment areas, can not reach the design service life of the transformer. In addition, the operation temperature change span of the transformer is large, when one transformer is put into operation from a standby state or is withdrawn from operation to standby, the temperature difference between day and night is about 40 ℃, and the allowable temperature rise range of the transformer up to 65 ℃ is considered, so that the normal working temperature of the transformer can reach 105 ℃. The corrosion action of corrosion factors such as chloride ions, oxygen molecules and the like on an anticorrosive coating is greatly accelerated by alternation of high and low temperatures, in order to achieve the designed service life, a solvent type epoxy zinc-rich heavy-duty anticorrosive coating system is basically adopted for corrosion prevention in a marine corrosion environment or an atmospheric corrosion area at present, the thickness of a dry film exceeds 500 mu m, and the problems of poor heat conductivity, poor binding force with a protective substrate and the like are brought while the problem of corrosion prevention is solved by excessively high film thickness, so that the comprehensive service performance of the transformer is influenced. In general, a heat conducting coating is mainly formed by adding some fillers with good heat conducting property, such as carbon black, aluminum oxide, boron nitride, silicon carbide, metal copper, silver and the like, into the coating to realize the heat conducting function of the coating, and in order to achieve an ideal heat conducting and radiating effect, high fillers (volume fraction > 50%) are usually added, so that the problems of mechanical property reduction, defect increase, corrosion protection property reduction and the like of the coating can be caused while the heat conducting and radiating effect is improved. Therefore, the research on an anticorrosion heat-conducting coating system which has a good anticorrosion effect and has heat-conducting performance is particularly urgent.

Due to excellent mechanical property, thermal property, corrosion resistance and the like, the epoxy resin is widely applied to various fields of aerospace, building traffic, electronic and electrical appliances and the like. However, the commonly used epoxy resins generally use petroleum-based compounds such as bisphenol a and bisphenol F as raw materials, and the aging resistance and ultraviolet resistance of the epoxy resins are poor due to the fact that the epoxy resins contain structural units such as aromatic benzene rings.

In addition, with the increasing depletion of petroleum resources, the search for sustainable, high-quality, inexpensive alternatives to petroleum is a key to the existence and development of the polymer industry. The bio-based high polymer material takes renewable resources as a main raw material, reduces the consumption of petrochemical products in the plastic industry, reduces the pollution to the environment in the production process of petroleum-based raw materials, is an important development direction of the current high polymer material, and has important actual value and wide development space.

Disclosure of Invention

The main object of the present invention is to provide a coating system and a process for its preparation, which overcome the disadvantages of the prior art.

The invention also aims to provide an anticorrosion and heat-conducting integrated coating formed by the coating system and a preparation method thereof.

Still another object of the present invention is to provide a coated article, and the use of the aforementioned corrosion-resistant and heat-conductive integrated coating or coated article in the preparation of electrical equipment.

In order to achieve the purpose, the technical scheme adopted by the invention comprises the following steps:

the embodiment of the invention provides a coating system for forming an anticorrosion heat-conducting integrated coating, which comprises a primer and/or a finish, wherein the primer and/or the finish comprise a curable resin, a high heat-conducting filler, an auxiliary agent and a dispersing agent, and the dispersing agent is derived from a bio-based monomer and has two or more functional groups of carboxyl, hydroxyl and carbonyl.

The embodiment of the invention also provides an anticorrosion heat-conduction integrated coating which is formed by the coating system.

The embodiment of the invention also provides a preparation method of the coating system, which comprises the following steps:

mixing a high-thermal-conductivity filler and a dispersant in an organic solvent to obtain a first dispersion solution, mixing the first dispersion solution with epoxy resin to form a first mixed solution, and mixing the first mixed solution with zinc powder, polyamide wax, cyclohexanone, xylene, talc powder and an auxiliary agent to prepare a primer;

and/or mixing the high-thermal-conductivity filler and the dispersing agent in an organic solvent to obtain a second dispersion liquid, mixing the second dispersion liquid with fluororesin to form a second mixed liquid, and mixing the second mixed liquid with fumed silica, propylene glycol methyl ether acetate, rutile titanium dioxide, a pigment and filler, a curing accelerator and an auxiliary agent to prepare the finish paint.

The embodiment of the invention also provides a preparation method of the anticorrosion heat-conduction integrated coating, which comprises the following steps:

preparing a coating system by adopting the method to obtain a finish coat and/or a primer;

preparing a primer into a film, and curing the film at a first temperature to form a bottom layer, wherein the first temperature is 5-35 ℃, preferably 5-25 ℃, and further preferably 10-20 ℃;

and/or preparing the finishing coat into a film, and curing the film at a second temperature to form the surface layer, wherein the second temperature is 5-35 ℃, preferably 5-25 ℃, and further preferably 10-20 ℃.

The embodiment of the invention also provides a coated product which comprises a substrate and the anticorrosion heat-conduction integrated coating coated on the surface of the substrate, wherein the anticorrosion heat-conduction integrated coating is the anticorrosion heat-conduction integrated coating or the anticorrosion heat-conduction integrated coating prepared by the method.

The embodiment of the invention also provides the application of the corrosion-resistant heat-conducting integrated coating or the coated product in the preparation of electric power equipment.

Compared with the prior art, the invention has the beneficial effects that:

(1) the coating system is divided into a primer and a finish, the bio-based dispersing agent and the high-thermal-conductivity filler are doped in the coating system, the used key raw materials have the characteristics of low price, high thermal conductivity, environmental friendliness, good weather resistance and excellent comprehensive performance, and the coating system has good corrosion resistance and also has high thermal conductivity.

(2) The preparation method of the coating system and the anticorrosion heat-conduction integrated coating is simple to operate, easy to implement, good in controllability and strong in operability, is beneficial to reducing the production cost of industrial production, is beneficial to industrial production, and has wide application prospect.

(3) The anticorrosion heat-conducting integrated coating or the coated product provided by the embodiment of the invention can be used for preparing electric power equipment, such as anticorrosion and heat conduction of a transformer for a power grid and auxiliary related equipment of the transformer.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only some embodiments recorded in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1a is a graph showing the effect of a composite system of primer 1 and topcoat 1 of paint 1 after 500 hours of neutral salt spray after film coating in examples 1 and 2 of the present invention;

FIG. 1b is a graph showing the effect of the composite system of primer 2 and topcoat 2 of paint 2 after 500 hours of neutral salt spray after film coating in examples 3 and 4 of the present invention;

FIG. 1c is a graph showing the effect of the composite system of primer 3 and topcoat 3 of paint 3 after 500 hours of neutral salt spray after film coating in examples 5 and 6 of the present invention;

FIG. 1d is a graph showing the effects of neutral salt spray for 500 hours after the primer coating 4 and the topcoat coating 4 in examples 7 and 8 of the present invention are applied;

FIG. 2a is a graph of a sample for measuring thermal conductivity after a composite system of paint 1 primer and paint 1 topcoat is coated in examples 1 and 2 of the present invention;

FIG. 2b is a graph of a sample for measuring thermal conductivity after a composite system of primer 2 and topcoat 2 of paint in examples 3 and 4 of the present invention is coated;

FIG. 2c is a graph of a sample for thermal conductivity measurement after the composite system of paint 3 primer and paint 3 topcoat was coated in examples 5 and 6 of the present invention;

FIG. 2d is a graph of a sample for measuring thermal conductivity after coating with a composite system of paint 4 primer and paint 4 topcoat in examples 7 and 8 of the present invention.

Detailed Description

In view of the deficiencies in the prior art, the inventors of the present invention have made extensive studies and extensive practices to provide technical solutions of the present invention. The technical solution, its implementation and principles, etc. will be further explained as follows.

The coating system provided by the embodiment of the invention is used for forming an anticorrosion heat-conducting integrated coating and comprises a primer and/or a finish, wherein the primer and/or the finish comprise a curable resin, a high heat-conducting filler, an auxiliary agent and a dispersing agent, and the dispersing agent is derived from a bio-based monomer and has two or more functional groups of carboxyl, hydroxyl and carbonyl.

In some embodiments, the dispersant has any one of the following structural formulas:

in some embodiments, the dispersant is selected from triallyl citrate and/or glycidyl citrate.

In some embodiments, the primer comprises the following components in parts by mass:

in some embodiments, the topcoat comprises the following components in parts by weight:

in some embodiments, the high thermal conductive filler includes any one or a combination of two or more of boron nitride, aluminum nitride, and silicon nitride, and is a micro-or nano-scale powder.

Further, the boron nitride is powder with the grain diameter of 40-60nm, the aluminum nitride is spherical powder with the grain diameter of 20-25 μm, and the silicon nitride is a beta-type sheet structure with the size of 300-700 nm;

in some embodiments, the auxiliary agent includes any one or a combination of two or more of bentonite, a silane coupling agent, a leveling agent, and a defoaming agent, but is not limited thereto.

Further, the leveling agent includes elvan 3777 and/or elvan 3236.

Further, the silane coupling agent comprises KH560 and/or KH 570.

Further, the antifoaming agent comprises BYK085 and/or BYK 051.

In some embodiments, the primer further comprises a first curing agent comprising a polyamide 650 curing agent and/or a cardanol amine curing agent;

further, the mass ratio of the epoxy resin to the first curing agent is 5:1-1: 5.

In some embodiments, the epoxy resin is present in an amount of 15 to 20% by weight of the total primer.

In some embodiments, the epoxy resin comprises a mixture of epoxy E20 and epoxy E44.

Further, the mass ratio of the epoxy E20 to the epoxy E44 is 4: 1-7: 1.

In some embodiments, the topcoat further includes a second curing agent comprising an HDI trimer curing agent and/or an HDI biuret curing agent.

Further, the mass ratio of the fluororesin to the second curing agent is 5:1 to 1: 5.

In some embodiments, the fluororesin is present in an amount of 45 to 60% by weight of the total mass of the topcoat;

in some embodiments, the fluororesin comprises eteflo 4101 and/or eteflo 4102.

Correspondingly, the embodiment of the invention also provides an anticorrosion heat-conduction integrated coating which is formed by any one of the coating systems.

Correspondingly, the embodiment of the invention also provides a preparation method of the coating system, which comprises the following steps:

In some embodiments, the method of making further comprises: mixing the first mixed solution with zinc powder, polyamide wax, cyclohexanone, xylene, talcum powder and an auxiliary agent, and then adding a first curing agent to prepare a primer; and/or mixing the second mixed solution with gas-phase silicon dioxide, propylene glycol methyl ether acetate, rutile titanium dioxide, pigment filler, a curing accelerator and an auxiliary agent, and then adding a second curing agent to prepare the finish paint.

Wherein, after the first curing agent or the second curing agent is added, the mixture is stirred uniformly.

In some embodiments, the method of making further comprises: mixing the high-thermal-conductivity filler and the dispersing agent in an organic solvent, and then carrying out magnetic stirring and ultrasonic dispersion to obtain the first dispersion liquid or the second dispersion liquid.

Further, the magnetic stirring time is 2-5min, and the ultrasonic dispersion time is 1-8 h.

Further, the power of the ultrasonic dispersion is 20-75KHz, preferably 30-70 KHz.

Wherein, the instrument used for ultrasonic dispersion is an ultrasonic cleaner.

Further, in the preparation process of the primer, after the first mixed solution is mixed with the zinc powder, the polyamide wax, the cyclohexanone, the dimethylbenzene, the talcum powder and the auxiliary agent, the stirring is carried out for 45min to 60min under the conditions of 1800 and 2500 r/min.

Further, in the preparation process of the finish paint, after the second mixed solution is mixed with the fumed silica, the propylene glycol methyl ether acetate, the rutile titanium dioxide, the pigment filler, the curing accelerator and the auxiliary agent, stirring is carried out for 45min to 60min under the condition of 1800-2500 r/min.

In some embodiments, the organic solvent comprises any one or a combination of two or more of toluene, xylene, acetone, tetrahydrofuran, ethanol, and dimethylsulfoxide.

In some embodiments, the mass ratio of the high thermal conductive filler to the dispersant is 1:2 to 10:1, and the mass ratio of the high thermal conductive filler to the epoxy resin or the fluororesin is 1:500 to 1: 100.

Correspondingly, the embodiment of the invention also provides a preparation method of the anticorrosion heat-conducting integrated coating, which comprises the following steps:

and/or preparing the finishing coat into a film, and curing the film at a second temperature to form a surface layer, wherein the second temperature is 5-35 ℃, preferably 5-25 ℃, and more preferably 10-20 ℃.

Wherein, the primer or the finishing coat can be coated (brushed or sprayed) on the surface of the substrate and cured into a film.

In some embodiments, the facing layer overlies the bottom layer.

Correspondingly, the embodiment of the invention also provides a coated product, which comprises a base material and the anticorrosion heat-conduction integrated coating coated on the surface of the base material, wherein the anticorrosion heat-conduction integrated coating is the anticorrosion heat-conduction integrated coating.

In some embodiments, the substrate comprises tinplate or carbon steel.

Correspondingly, the embodiment of the invention also provides the application of the corrosion-resistant heat-conducting integrated coating or the coated product in the preparation of electric equipment.

For example for corrosion protection and heat conduction.

In some embodiments, the electrical equipment comprises a grid transformer and/or transformer accessory related equipment.

Including but not limited to use on transformers, power switches, among others.

The technical solution of the present invention will be described in further detail below with reference to examples. However, the examples are chosen only for the purpose of illustrating the invention and are not to be construed as limiting the scope of the invention.

Unless defined otherwise, 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 invention belongs.

As used herein, the use of "about" before a particular numerical value is stated means that the value does not vary by more than 1% from the recited numerical value. For example, "about 10" includes 9.9 and 10.1 and all values in between.

As used herein, the term "comprising" or "includes" can be open, semi-closed, and closed. That is, the term also encompasses "consisting essentially of …" or "consisting of …".

The invention is illustrated below with reference to specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Test methods in which specific conditions are not specified in the following examples are generally in accordance with conventional conditions or in accordance with conditions recommended by the manufacturer, unless otherwise specified, percentages and parts are by weight.

Example 1:

coating 1-primer:

0.03g of dispersant, 0.15g of boron nitride and 0.15g of aluminum nitride powder are dispersed in 0.4L of tetrahydrofuran solution, and are stirred for 2min by magnetic force and ultrasonically mixed for 1.5h, wherein the ultrasonic dispersion power is 50KHz, and then the dispersion slurry 1 is formed.

Adding the dispersion slurry 1 into 25g of epoxy resin (containing 21g of epoxy resin E20 and 4g of epoxy resin E44), then sequentially adding 55g of zinc powder, 1g of bentonite, 6g of xylene, 2g of polyamide wax, 3g of cyclohexanone, 5.2g of talcum powder, 1g of polyethylene ester and 1.8g of flatting agent, stirring uniformly, adding 10g of polyamide curing agent, and stirring uniformly to obtain the primer of the coating 1.

Example 2:

1-finish paint

Dispersing 2g of dispersing agent, 5g of boron nitride and 15g of aluminum nitride powder in 0.5L of tetrahydrofuran solution, stirring for 2min by using magnetic force and ultrasonically mixing for 1.5h, wherein the power of ultrasonic dispersion is 30KHz, and forming dispersed slurry 1.

Adding the dispersion slurry 1 into 48g of fluororesin, then sequentially adding 0.5g of aerosil, 11.9g of propylene glycol methyl ether acetate, 0.3g of Effka 3777, 0.2g of Disbamuron OX-70 antifoaming agent, 10g of rutile titanium dioxide and 7.1g of color matching pigment, uniformly stirring, adding 6g of HDI trimer curing agent, and uniformly stirring to obtain the finish paint of the coating 1.

Example 3:

coating 2-primer

0.03g of dispersant, 0.15g of boron nitride and 0.15g of silicon nitride powder are dispersed in 0.4L of tetrahydrofuran solution, stirred for 3min by magnetic force and ultrasonically mixed for 1.5h, and the power of ultrasonic dispersion is 20KHz, so that dispersed slurry 1 is formed.

Adding the dispersion slurry 1 into 25g of epoxy resin (containing 21g of epoxy resin E20 and 4g of epoxy resin E44), then sequentially adding 55g of zinc powder, 1g of bentonite, 6g of xylene, 2g of polyamide wax, 3g of cyclohexanone, 5.2g of talcum powder, 1g of polyethylene wax and 1.8g of flatting agent, uniformly stirring, adding 4g of polyamide curing agent and 2g of cardanol amine curing agent, and uniformly stirring to obtain the paint 2 primer.

Example 4:

2-finish paint

Dispersing 2g of dispersing agent, 5g of boron nitride and 15g of silicon nitride powder in 0.5L of tetrahydrofuran solution, stirring for 5min by using magnetic force and ultrasonically mixing for 1h, wherein the power of ultrasonic dispersion is 70KHz, and forming dispersed slurry 1.

Adding the dispersion slurry 1 into 48g of fluororesin, then sequentially adding 0.5g of fumed silica, 11.9g of propylene glycol monomethyl ether acetate, 0.3g of Effka 3777, 0.2g of Disbaron OX-70 defoaming agent, 10g of rutile titanium dioxide and 7.1g of color matching pigment, uniformly stirring, adding 8g of HDI biuret curing agent, and uniformly stirring to obtain the finish paint 2.

Example 5:

coating 3-primer:

dispersing 3g of dispersing agent, 6g of boron nitride and 6g of silicon nitride powder in 0.4L of tetrahydrofuran solution, stirring for 2min by using magnetic force and ultrasonically mixing for 1.5h, wherein the power of ultrasonic dispersion is 50KHz, and forming dispersed slurry 1.

Adding the dispersion slurry 1 into 27g of epoxy resin (containing 23g of epoxy resin E20 and 4g of epoxy resin E44), then sequentially adding 55g of zinc powder, 1.5g of bentonite, 7g of xylene, 3g of polyamide ester, 4g of cyclohexanone, 4g of talcum powder, 1.5g of polyethylene ester and 2g of flatting agent, stirring uniformly, adding 20g of polyamide curing agent, and stirring uniformly to obtain the primer of the coating 1.

Example 6:

coating 3-finish paint

Dispersing 2g of dispersing agent, 5g of boron nitride and 5g of aluminum nitride powder in 0.5L of tetrahydrofuran solution, stirring for 2min by using magnetic force and ultrasonically mixing for 1.5h, wherein the power of ultrasonic dispersion is 75KHz, and forming dispersed slurry 1.

Adding the dispersion slurry 1 into 48g of fluororesin, then sequentially adding 1g of gas silicon, 8g of propylene glycol monomethyl ether acetate, 0.3g of Effka 3777, 0.2g of Dissbarone OX-70 defoaming agent, 5g of rutile titanium dioxide and 5g of color matching pigment, uniformly stirring, adding 4g of HDI trimer curing agent, and uniformly stirring to obtain the finish paint 1.

Example 7:

paint 4-primer

0.5g of dispersant, 0.25g of boron nitride and 0.25g of silicon nitride powder are dispersed in 0.4L of tetrahydrofuran solution, and are stirred for 5min by magnetic force and ultrasonically mixed for 1.5h, wherein the ultrasonic dispersion power is 30KHz, and then the dispersion slurry 1 is formed.

Adding the dispersion slurry 1 into 17g of epoxy resin (containing 14g of epoxy resin E20 and 3g of epoxy resin E44), then sequentially adding 55g of zinc powder, 1g of bentonite, 4g of xylene, 2g of polyamide wax, 1.5g of cyclohexanone, 4g of talcum powder, 1g of polyethylene wax and 1g of flatting agent, stirring uniformly, adding 4g of polyamide curing agent and 4g of cardanol amine curing agent, and stirring uniformly to obtain the primer 2 of the coating.

Example 8:

coating 4-finish

Dispersing 8g of dispersing agent, 20g of boron nitride and 20g of silicon nitride powder in 0.5L of tetrahydrofuran solution, stirring for 2min by using magnetic force and ultrasonically mixing for 8h, wherein the power of ultrasonic dispersion is 20KHz, and forming dispersed slurry 1.

Adding the dispersion slurry 1 into 48g of fluororesin, then sequentially adding 1g of fumed silica, 12g of propylene glycol methyl ether acetate, 0.3g of Effka 3777, 0.2g of Dissbarone OX-70 defoaming agent, 15g of rutile titanium dioxide and 9g of color matching pigment, uniformly stirring, adding 8g of HDI biuret curing agent, and uniformly stirring to obtain the paint 2 finish.

Testing

The coatings prepared in examples 1 to 8 were coated on 316L stainless steel by a wire coater while controlling the average film thickness of the primer to about 40 μm and the average film thickness of the topcoat to about 25 μm, respectively, and after curing at room temperature for 7 days, salt spray resistance was measured in accordance with GB 6458-86.

The coatings prepared in examples 1 to 8 were each applied by wire coater to 316 stainless steel L discs previously cut to a diameter of 12.7mm, with the average thickness of the primer being controlled to about 40 μm and the average thickness of the topcoat being controlled to about 25 μm, and after curing at room temperature for 7 days, the coatings were tested in accordance with GB/T22588-2008.

Wherein, fig. 1a and fig. 2a are respectively an effect graph and a thermal conductivity test sample of a 1# composite coating prepared by using the primer in example 1 and the topcoat in example 2 after 500 hours of neutral salt fog, fig. 1b and fig. 2b are respectively an effect graph and a thermal conductivity test sample of a 2# composite coating prepared by using the primer in example 3 and the topcoat in example 4 after 500 hours of neutral salt fog, fig. 1c and fig. 2c are respectively an effect graph and a thermal conductivity test sample of a 3# composite coating prepared by using the primer in example 5 and the topcoat in example 6 after 500 hours of neutral salt fog, and fig. 1d and fig. 2d are respectively an effect graph and a thermal conductivity test sample of a 4# composite coating prepared by using the primer in example 7 and the topcoat in example 8 after 500 hours of neutral salt fog.

It can be seen that the composite coatings using the coating designs prepared in examples 1-8 have good adhesion and thermal conductivity.

Table 1 shows the properties of each index.

TABLE 1 composite coating Performance Table

As can be seen from Table 1, the anticorrosion heat-conducting integrated coating provided by the invention has good adhesive force and heat conductivity. The dispersant added in the embodiment can well enable main heat-conducting materials such as boron nitride, aluminum nitride and silicon nitride to be uniformly dispersed in the coating system, and the composite coating system has good corrosion-resistant and heat-conducting integrated performance due to the good dispersing effect.

In addition, the inventor also carries out corresponding experiments by using other raw materials and other process conditions listed above instead of various raw materials and corresponding process conditions in the examples 1 to 8, and the contents to be verified are similar to the products in the examples 1 to 8. Therefore, the contents of the verification of each example are not described herein one by one, and the excellent points of the present invention are described only by examples 1 to 8 as representative examples.

It should be understood that the above describes only some embodiments of the present invention and that various other changes and modifications may be affected therein by one of ordinary skill in the related art without departing from the scope or spirit of the invention.

Claims

1. A coating system for forming an anti-corrosive thermally conductive integral coating, the coating system comprising a primer and a topcoat, characterized in that:

the primer comprises the following components in parts by weight: 100 parts of zinc powder, 30-45 parts of epoxy resin, 1-10 parts of polyamide wax, 5-10 parts of cyclohexanone, 5-15 parts of dimethylbenzene, 1-25 parts of high-thermal-conductivity filler, 1-15 parts of talcum powder, 1-10 parts of assistant and 0.1-5 parts of dispersing agent;

the finish paint comprises the following components in parts by weight: 100 parts of fluororesin, 1-5 parts of fumed silica, 20-30 parts of propylene glycol methyl ether acetate, 1-5 parts of an auxiliary agent, 10-50 parts of a high-heat-conductivity filler and 10-40 parts of rutile titanium dioxide; 1-40 parts of pigment and filler, 1-10 parts of curing accelerator and 1-10 parts of dispersing agent;

the dispersant has any one of the following structural formulas:

2. the coating system of claim 1, wherein: the high heat conduction filler comprises any one or the combination of more than two of boron nitride, aluminum nitride and silicon nitride.

3. The coating system of claim 2, wherein: the boron nitride is powder with the grain diameter of 40-60nm, the aluminum nitride is spherical powder with the grain diameter of 20-25 mu m, and the silicon nitride is a beta-type sheet structure with the size of 300-700 nm.

4. The coating system of claim 1, wherein: the auxiliary agent comprises any one or the combination of more than two of bentonite, a silane coupling agent, a flatting agent and a defoaming agent.

5. The coating system of claim 4, wherein: the leveling agent comprises Effka 3777 and/or Effka 3236, the silane coupling agent comprises KH560 and/or KH570, and the defoaming agent comprises BYK085 and/or BYK 051.

6. The coating system according to claim 1, characterized in that: the primer further comprises a first curing agent, and the first curing agent comprises a polyamide 650 curing agent and/or a cardanol amine curing agent.

7. The coating system of claim 6, characterized in that: the mass ratio of the epoxy resin to the first curing agent is 5:1-1: 5.

8. The coating system according to claim 1 or 7, characterized in that: the content of the epoxy resin is 15-20% by mass of the total primer.

9. The coating system according to claim 1 or 7, characterized in that: the epoxy resin comprises a mixture of epoxy E20 and epoxy E44.

10. The coating system according to claim 9, characterized in that: the mass ratio of the epoxy E20 to the epoxy E44 is 4: 1-7: 1.

11. The coating system according to claim 1, characterized in that: the finish paint also comprises a second curing agent, wherein the second curing agent comprises an HDI tripolymer curing agent and/or an HDI biuret curing agent.

12. The coating system of claim 11, characterized in that: the mass ratio of the fluororesin to the second curing agent is 5:1-1: 5.

13. The coating system according to claim 1 or 12, characterized in that: based on the total mass of the finish paint, the content of the fluororesin is 45-60%.

14. The coating system according to claim 1 or 12, characterized in that: the fluororesin includes ETERFLON 4101 and/or ETERFLON 4102.

15. An anti-corrosive thermally conductive integrated coating formed from the coating system of any one of claims 1-14.

16. A method of preparing a coating system as claimed in any one of claims 1 to 14, characterized in that it comprises:

mixing a high-thermal-conductivity filler and a dispersant in an organic solvent to obtain a first dispersion solution, mixing the first dispersion solution with epoxy resin to form a first mixed solution, and mixing the first mixed solution with zinc powder, polyamide wax, cyclohexanone, xylene, talcum powder and an auxiliary agent to prepare a primer;

mixing the high-thermal-conductivity filler and the dispersing agent in an organic solvent to obtain a second dispersion liquid, mixing the second dispersion liquid with fluororesin to form a second mixed liquid, and mixing the second mixed liquid with fumed silica, propylene glycol methyl ether acetate, rutile titanium dioxide, a pigment filler, a curing accelerator and an auxiliary agent to obtain the finish paint.

17. The method of claim 16, further comprising: and mixing the first mixed solution with zinc powder, polyamide wax, cyclohexanone, xylene, talcum powder and an auxiliary agent, and then adding a first curing agent to prepare the primer.

18. The method of claim 16, further comprising: and mixing the second mixed solution with fumed silica, propylene glycol methyl ether acetate, rutile titanium dioxide, pigment filler, a curing accelerator and an auxiliary agent, and then adding a second curing agent to prepare the finish paint.

19. The method of claim 16, further comprising: mixing the high-thermal-conductivity filler and the dispersing agent in an organic solvent, and then carrying out magnetic stirring and ultrasonic dispersion to obtain the first dispersion liquid or the second dispersion liquid.

20. The method of claim 19, wherein: the magnetic stirring time is 2-5min, and the ultrasonic dispersion time is 1-8 h.

21. The method of claim 19, wherein: the power of the ultrasonic dispersion is 20-75 KHz.

22. The method of claim 21, wherein: the power of the ultrasonic dispersion is 30-70 KHz.

23. The method of claim 16, wherein: the organic solvent comprises any one or the combination of more than two of toluene, xylene, acetone, tetrahydrofuran, ethanol and dimethyl sulfoxide.

24. The method of claim 16, wherein: the mass ratio of the high heat conduction filler to the dispersing agent is 1:2-10:1, and the mass ratio of the high heat conduction filler to the epoxy resin or the fluororesin is 1:500-1: 100.

25. A preparation method of an anticorrosion heat-conduction integrated coating is characterized by comprising the following steps:

preparing a coating system using the method of any one of claims 16-24 to obtain a top coat and a primer;

preparing a primer into a film, and curing the primer at a first temperature to form a bottom layer, wherein the first temperature is 5-35 ℃;

preparing a finish paint into a film, and curing at a second temperature to form a surface layer, wherein the second temperature is 5-35 ℃;

the surface layer is covered on the bottom layer.

26. The method of claim 25, wherein: the first temperature or the second temperature is 5-25 ℃.

27. The method of claim 26, wherein: the first temperature or the second temperature is 10-20 ℃.

28. A coated article comprising a substrate and an integrated corrosion and heat conductive coating applied to a surface of the substrate, wherein the integrated corrosion and heat conductive coating is the integrated corrosion and heat conductive coating of claim 15 or the integrated corrosion and heat conductive coating prepared by the method of any one of claims 25 to 27.

29. The coated article of claim 28, wherein: the substrate comprises tinplate or carbon steel.

30. Use of an anti-corrosive thermally conductive integrated coating according to claim 15, an anti-corrosive thermally conductive integrated coating prepared by a method according to any one of claims 25 to 27, or a coated article according to any one of claims 28 to 29 for the preparation of an electrical power device.

31. The use according to claim 30, wherein: the power equipment comprises a transformer for a power grid and/or transformer accessory related equipment.