Acrylic acid residual carbon composite graphene electrothermal coating and preparation method thereof

Abstract

The invention relates to the technical field of electrothermal coatings, in particular to an acrylic acid residual carbon composite graphene electrothermal coating and a preparation method thereof. The acrylic acid residual carbon composite graphene electrothermal coating comprises the following components in parts by mass: 1 part of acrylic acid residual carbon composite graphene, 0.4-1 part of hexagonal boron nitride, 0.4-1.5 parts of a binder, 0.1-0.5 part of a dispersant and 20-100 parts of a solvent, the acrylic acid residual carbon composite graphene is mainly obtained by sequentially grinding and sintering graphene and acrylic acid modified polysiloxane resin. According to the acrylic acid residual carbon composite graphene electrothermal coating provided by the invention, the structural stability and electrothermal performance stability of the graphene electrothermal coating at high temperature are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrothermal coatings, and particularly to an acrylic residual carbon composite graphene electrothermal coating and a preparation method thereof. Background Art

[0002] At present, in electrothermal coating technology, there are various conductive fillers, such as metal materials, metal oxide materials, carbon-based materials, and other semiconductor materials. Due to its low density, low resistivity, excellent thermal and electrical conductivity, high electrothermal conversion efficiency, and uniform heat generation temperature distribution, carbon-based materials have always been used as ideal electrothermal materials to achieve rapid heating and effective heat generation. Therefore, carbon-based materials, especially graphene, have attracted more and more attention from researchers.

[0003] Graphene is a quasi-two-dimensional nanocarbon crystal material with ultra-light, ultra-thin, ultra-strong, and extremely large specific surface area. The areal density is about 0.77 mg / m 2 , the thickness of a single-layer graphene is about 0.34 nm, and the theoretical specific surface area is 2630 m 2 / g, and it has very high electrical and thermal conductivity. In recent years, due to the advantages of the coating prepared from graphene electrothermal coating, such as rapid heating, uniform heating, high electrothermal conversion, and stable operation at any voltage, as well as the characteristics of being lightweight and having a long service life, it has attracted extensive attention in many fields such as construction, agriculture, automobiles, and electrical appliances.

[0004] There are numerous reports on graphene electrothermal coatings. However, most of the existing graphene electrothermal coatings face challenges in high-temperature environments. When using graphene as an electrothermal material, due to its single-layer structure and thermal expansion characteristics at high temperatures, the stress is easily generated between its layers due to thermal expansion, and graphene, especially at the defect sites, will oxidize at high temperatures, which leads to the decline of the stability and electrothermal performance of graphene electrothermal coatings. Traditional graphene electrothermal coatings often perform poorly in the face of these challenges, and there is a risk of performance decline or premature failure, thus limiting their application scope and service life under high-temperature conditions. And in industrial heating such as pipeline heating, high-temperature heating furnaces, etc., as well as in daily life, such as ovens, high-temperature electric heating, etc., graphene electrothermal coatings with higher and more stable heating temperatures are required.

[0005] In view of this, this invention is specifically proposed. Summary of the Invention

[0006] The first object of the present invention is to provide an acrylic residual carbon composite graphene electrothermal coating, which improves the structural stability and electrothermal performance stability of graphene electrothermal coatings at high temperatures.

[0007] The second object of the present invention is to provide a method for preparing the above-mentioned acrylic acid residual carbon composite graphene electric heating coating, which has simple steps.

[0008] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0009] In a first aspect, the present invention provides an acrylic residual carbon composite graphene electric heating coating, which comprises the following components in parts by mass:

[0010] 1 part of acrylic acid residual carbon composite graphene, 0.4-1 part of hexagonal boron nitride, 0.4-1.5 parts of binder, 0.1-0.5 parts of dispersant and 20-100 parts of solvent;

[0011] The acrylic acid residual carbon composite graphene is mainly obtained by grinding and sintering graphene and acrylic acid modified polysiloxane resin in sequence.

[0012] Furthermore, the sintering includes: performing a first sintering at 200-250° C. for 2-4 hours, and then performing a second sintering at 595-605° C. for 25-35 minutes.

[0013] Furthermore, the mass ratio of the graphene to the acrylic modified polysiloxane resin is 1:(0.6-0.8).

[0014] Furthermore, in the Raman spectrum of the graphene, the ratio of the D peak intensity to the G peak intensity is ≤1 / 10; and in the graphene, the molar ratio of oxygen to carbon is ≤1 / 20.

[0015] Furthermore, the viscosity of the acrylic modified polysiloxane resin is 30 to 80 seconds when the solid content is 50%.

[0016] Furthermore, the particle size D50 of the hexagonal boron nitride is 17-22 μm.

[0017] Furthermore, the binder includes at least one of methylphenyl silicone resin, methylphenyl polysiloxane resin, acrylic modified polysiloxane resin and epoxy modified silicone resin.

[0018] Further, the dispersant includes polyvinyl pyrrolidone K30;

[0019] And / or, the solvent comprises N-methylpyrrolidone.

[0020] In a second aspect, the present invention also provides a method for preparing the acrylic acid residual carbon composite graphene electrothermal coating as described above, comprising the following steps:

[0021] The components are mixed evenly to obtain the acrylic acid residual carbon composite graphene electric heating paint.

[0022] Further, the preparation method of the acrylic residual carbon composite graphene electrothermal coating comprises the following steps:

[0023] Mix a solvent, a dispersant, acrylic residual carbon composite graphene, and hexagonal boron nitride to obtain a dispersion; mix the dispersion and a binder to obtain the acrylic residual carbon composite graphene electrothermal coating.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] The present invention provides an acrylic residual carbon composite graphene electrothermal coating; by using a polysiloxane resin with acrylic groups through low-temperature - high-temperature step-by-step sintering, an elastic amorphous acrylic residual carbon left after preferentially carbonizing part of the acrylic functional groups is combined with graphene to coat the edges, defects, etc. of its sheet diameter that are easily oxidized at high temperatures, and modified into a material with thermal and electrical conductivity; then sintering at high temperature to cure the siloxane chains into silicon oxide to form the heating element material, obtaining acrylic residual carbon composite graphene; the acrylic residual carbon composite graphene can enhance the high-temperature stability of graphene. At high temperatures, the acrylic residual carbon not only plays its elastic role to buffer the stress generated by the thermal expansion of graphene, but also can protect the graphene defects from being oxidized, enabling the coating to maintain a relatively stable structure; at the same time, hexagonal boron nitride with a structure similar to that of graphene and excellent thermal stability is used to inhibit the thermal expansion of graphene sheets in the two-dimensional scale; thereby improving the structural stability and electrothermal performance stability of the graphene electrothermal coating at high temperatures, and thus solving the problem of poor heating performance caused by the unstable structure of the graphene electrothermal coating at high temperatures; the electrothermal coating prepared from the acrylic residual carbon composite graphene electrothermal coating has high adhesion, a relatively low room temperature resistivity, can heat to 430 - 475 °C under a 24V voltage, and the change rate of the room temperature resistance before and after aging is less than 1%, having broad application prospects and market potential in the field of graphene electrothermal coatings. Specific Embodiments

[0026] The technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments. However, those skilled in the art will understand that the following described embodiments are some embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention. Those not specified in the embodiments are carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments not specified in the manufacturer are all conventional products that can be obtained through commercial purchase.

[0027] The acrylic residue carbon composite graphene electrothermal coating and its preparation method according to the embodiments of the present invention will be specifically described below.

[0028] In some embodiments of the present invention, an acrylic residue carbon composite graphene electrothermal coating is provided, which includes the following components by mass parts:

[0029] 1 part of acrylic residue carbon composite graphene, 0.4 - 1 part of hexagonal boron nitride, 0.4 - 1.5 parts of binder, 0.1 - 0.5 parts of dispersant, and 20 - 100 parts of solvent;

[0030] The acrylic residue carbon composite graphene is mainly obtained by successively grinding and sintering graphene and acrylic modified polysiloxane resin.

[0031] By adopting the acrylic residue carbon composite graphene in the present invention, the high-temperature stability of graphene can be enhanced; at high temperatures, the acrylic residue carbon not only plays its elastic role to buffer the stress generated by the thermal expansion of graphene, but also can protect the graphene defects from being oxidized, so that the coating can maintain a relatively stable structure; at the same time, hexagonal boron nitride with a structure similar to that of graphene and excellent thermal stability is used to inhibit the thermal expansion of graphene sheets in the two-dimensional scale; thereby improving the structural stability and electrothermal performance stability of the graphene electrothermal coating at high temperatures, and thus solving the technical problem that the graphene electrothermal coating in the prior art has poor heat generation performance due to unstable structure at high temperatures.

[0032] In some embodiments of the present invention, the mass ratio of the acrylic residue carbon composite graphene to the hexagonal boron nitride is 1:(0.4 - 1); typically but not restrictively, for example, the mass ratio of the acrylic residue carbon composite graphene to the hexagonal boron nitride can be 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, or the range value composed of any two of them;

[0033] The mass ratio of the acrylic residue carbon composite graphene to the binder is 1:(0.4 - 1.5); typically but not restrictively, for example, the mass ratio of the acrylic residue carbon composite graphene to the binder can be 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, or the range value composed of any two of them;

[0034] The mass ratio of the acrylic residue carbon composite graphene to the dispersant is 1:(0.1 - 0.5); typically but not restrictively, for example, the mass ratio of the acrylic residue carbon composite graphene to the dispersant can be 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, or the range value composed of any two of them;

[0035] The mass ratio of the acrylic acid residue carbon composite graphene to the solvent is 1:(20-100); typically but not limited to, for example, the mass ratio of the acrylic acid residue carbon composite graphene to the solvent can be 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, 1:100 or the range value composed of any two of them.

[0036] The acrylic acid residue carbon composite graphene of the present invention cooperates with hexagonal boron nitride. If no or less hexagonal boron nitride is added, the electrothermal performance and aging resistance of the coating prepared by the electrothermal coating will be reduced; if the content of hexagonal boron nitride is relatively high, and hexagonal boron nitride is an insulating material, it will hinder the electron transport between the graphene sheets, resulting in a significant reduction in the conductivity of the electrothermal coating, thereby deteriorating its electrothermal performance.

[0037] In some embodiments of the present invention, the sintering includes: performing the first sintering at 200-250°C for 2-4 h, and then performing the second sintering at 595-605°C for 25-35 min; typically but not limited to, for example, the temperature of the first sintering can be 200°C, 210°C, 220°C, 230°C, 240°C, 250°C or the range value composed of any two of them; if the temperature of the first sintering is too high or too low, the electrothermal temperature of the coating will be reduced and the aging resistance will be deteriorated; preferably, the sintering is performed in an air atmosphere.

[0038] The preparation of the acrylic acid residue carbon composite graphene of the present invention is to compound graphene with an acrylic acid-modified polysiloxane resin by mechanical grinding method, and then sinter the obtained composite material step by step at a low temperature of 200-250°C and a high temperature of 600±5°C to obtain an acrylic acid residue carbon composite graphene, the structure of which is that the acrylic acid residue carbon adheres to the edges and defects of the graphene sheet diameter and other parts that are easily oxidized and have unstable structures at high temperatures.

[0039] The present invention uses a polysiloxane resin with an acrylic group to be sintered step by step at a low temperature and a high temperature. First, sintering (carbonization) is performed at a low temperature, so that an elastic amorphous acrylic acid residue carbon left after partial carbonization of the acrylic functional group is compounded with graphene to coat the parts that are easily oxidized at high temperatures such as the edges and defects of its sheet diameter, and is modified into a material with thermal conductivity and electrical conductivity; then sintering at a high temperature cures the siloxane chain into silicon oxide to form the heating element material and obtain the acrylic acid residue carbon composite graphene.

[0040] In some embodiments of the present invention, the mass ratio of graphene to acrylic acid-modified polysiloxane resin is 1:(0.6 - 0.8); typically but not limitedly, for example, the mass ratio of graphene to acrylic acid-modified polysiloxane resin can be 1:0.6, 1:0.7, 1:0.8 or the range value composed of any two of them; adopting the above mass ratio of graphene to acrylic acid-modified polysiloxane resin is beneficial to improving the electrothermal performance of the prepared electrothermal coating.

[0041] In some embodiments of the present invention, in the Raman spectrum of graphene, the ratio of the intensity of the D peak to the intensity of the G peak ≤ 1 / 10; in graphene, the molar ratio of oxygen to carbon ≤ 1 / 20; preferably, the graphene is prepared by the method for preparing graphene in the patent with the application number CN108622887A.

[0042] The ratio of the D peak to the G peak of the graphene of the present invention is small, indicating that the graphene is low-defect graphene; if the ratio of the D peak to the G peak is large, it means that the graphene has large defects and the electrical properties of the corresponding material will decline.

[0043] In some embodiments of the present invention, the viscosity of the acrylic acid-modified polysiloxane resin at a solid content of 50% is 30 - 80 s; the acrylic acid-modified polysiloxane resin is prepared by the hydrolysis of phenyl and methyl monomers to form silanols and special acrylic monomers through a special process, and its viscosity (coat 4 cup, 25 °C) at a solid content of 50% is 30 - 80 s; preferably, the acrylic acid-modified polysiloxane resin includes the SH-024 acrylic acid-modified polysiloxane resin of Hubei Longsheng Sihai New Materials Co., Ltd.

[0044] In some embodiments of the present invention, the particle size D50 of hexagonal boron nitride is 17 - 22 μm.

[0045] In some embodiments of the present invention, the binder includes at least one of methyl phenyl silicone resin, methyl phenyl polysiloxane resin, acrylic acid-modified polysiloxane resin and epoxy-modified silicone resin; preferably, the binder includes acrylic acid-modified polysiloxane resin.

[0046] In some embodiments of the present invention, the dispersant includes polyvinylpyrrolidone K30.

[0047] In some embodiments of the present invention, the solvent includes N-methylpyrrolidone.

[0048] In some embodiments of the present invention, a method for preparing the above acrylic acid residue carbon composite graphene electrothermal coating is also provided, including the following steps:

[0049] Mix each component to obtain the acrylic acid residue carbon composite graphene electrothermal coating.

[0050] In some embodiments of the present invention, a method for preparing an acrylic residue carbon composite graphene electrothermal coating includes the following steps:

[0051] Mix a solvent, a dispersant, acrylic residue carbon composite graphene, and hexagonal boron nitride to obtain a dispersion; mix the dispersion and a binder to obtain an acrylic residue carbon composite graphene electrothermal coating.

[0052] In some embodiments of the present invention, a method for preparing an acrylic residue carbon composite graphene electrothermal coating specifically includes the following steps:

[0053] Add a dispersant to a solvent and perform high-speed shear dispersion. After complete dissolution, add acrylic residue carbon composite graphene and also add hexagonal boron nitride. First, stir and disperse with a high-speed disperser for 30 - 120 min, then put it into a sand mill for grinding and dispersing for 2 - 8 h to obtain a uniformly dispersed dispersion; in the above dispersion, add a binder and stir with a magnetic stirrer to completely dissolve the binder to obtain an acrylic residue carbon composite graphene electrothermal coating.

[0054] In some embodiments of the present invention, an electrothermal coating is also provided, which is prepared by using the above acrylic residue carbon composite graphene electrothermal coating.

[0055] In some embodiments of the present invention, the stable electrothermal temperature of the electrothermal coating at 24V voltage is 430 - 475 °C; the adhesion is grade 0 (refer to GB / T 9286 - 1998); the change rate of room temperature resistance before and after aging is less than 1% (refer to GB / T 1735 - 2009).

[0056] The electrothermal coating prepared by using the acrylic residue carbon composite graphene electrothermal coating of the present invention has a low room temperature resistivity, high adhesion, excellent electrothermal performance and aging resistance, and has broad application prospects and market potential in the field of graphene electrothermal coatings.

[0057] Example 1

[0058] The method for preparing the acrylic residue carbon composite graphene electrothermal coating provided in this example includes the following steps:

[0059] Weigh 10 g of graphene (the ratio of the intensity of the D peak to the intensity of the G peak in the Raman spectrum ≤ 1 / 10; the molar ratio of silicon oxygen to carbon ≤ 1 / 20) and 7 g of acrylic modified polysiloxane resin (Beilongsheng Sihai New Materials Co., Ltd., SH - 024) respectively. After mechanical grinding, a composite material is obtained; put the composite material into a muffle furnace and perform the first sintering at 250 °C for 2 h in an air atmosphere, and then perform the second sintering at 600 °C for 30 min to obtain acrylic residue carbon composite graphene;

[0060] Add 2 g of polyvinylpyrrolidone K30 to 200 g of N-methylpyrrolidone, place it in a disperser and stir to disperse. After complete dissolution, while stirring, add 10 g of the above-mentioned acrylic acid residual carbon composite graphene, and add 6 g of hexagonal boron nitride with a particle size D50 of 17 - 22 μm. After high-speed stirring and dispersing for 30 min, put it into a sand mill. Set the sand mill speed to 2300 rpm and carry out high-speed grinding and dispersing for 4 h to obtain a uniformly dispersed dispersion; then add 6 g of acrylic acid modified polysiloxane resin to the above dispersion, and stir with a magnetic stirrer to completely dissolve the acrylic acid modified polysiloxane resin to obtain an acrylic acid residual carbon composite graphene electrothermal coating.

[0061] Example 2

[0062] The preparation method of the acrylic acid residual carbon composite graphene electrothermal coating provided in this example includes the following steps:

[0063] Weigh 10 g of graphene (the ratio of the intensity of the D peak to the intensity of the G peak in the Raman spectrum ≤ 1 / 10; the molar ratio of silicon oxide to carbon ≤ 1 / 20) and 6 g of acrylic acid modified polysiloxane resin (Beilongsheng Sihai New Materials Co., Ltd., SH-024) respectively. After mechanical grinding, a composite material is obtained; the composite material is put into a muffle furnace and sintered for the first time at 240 °C for 2 h in an air atmosphere, and then sintered for the second time at 600 °C for 30 min to obtain acrylic acid residual carbon composite graphene;

[0064] Add 2 g of polyvinylpyrrolidone K30 to 200 g of N-methylpyrrolidone, place it in a disperser and stir to disperse. After complete dissolution, while stirring, add 10 g of the above-mentioned acrylic acid residual carbon composite graphene, and add 6 g of hexagonal boron nitride with a particle size D50 of 17 - 22 μm. After high-speed stirring and dispersing for 30 min, put it into a sand mill. Set the sand mill speed to 2300 rpm and carry out high-speed grinding and dispersing for 4 h to obtain a uniformly dispersed dispersion; then add 7 g of methylphenyl silicone resin to the above dispersion, and stir with a magnetic stirrer to completely dissolve the acrylic acid modified polysiloxane resin to obtain an acrylic acid residual carbon composite graphene electrothermal coating.

[0065] Example 3

[0066] The preparation method of the acrylic acid residual carbon composite graphene electrothermal coating provided in this example includes the following steps:

[0067] Weigh 10 g of graphene (the ratio of the intensity of the D peak to the intensity of the G peak in the Raman spectrum ≤ 1 / 10; the molar ratio of silicon oxygen to carbon ≤ 1 / 20) and 8 g of acrylic acid-modified polysiloxane resin (Beilongsheng Sihai New Materials Co., Ltd., SH-024) respectively. After mechanical grinding, a composite material is obtained. The composite material is placed in a muffle furnace and sintered for the first time at 230 °C for 3 h in an air atmosphere, and then sintered for the second time at 600 °C for 30 min to obtain acrylic acid residual carbon composite graphene;

[0068] Add 2 g of polyvinylpyrrolidone K30 to 200 g of N-methylpyrrolidone, place it in a disperser for stirring and dispersion. After complete dissolution, add 10 g of the above-mentioned acrylic acid residual carbon composite graphene while stirring, and add 6 g of hexagonal boron nitride with a particle size D50 of 17 - 22 μm. After high-speed stirring and dispersion for 30 min, it is put into a sand mill. The rotation speed of the sand mill is set at 2300 rpm, and high-speed grinding and dispersion are carried out for 4 h to obtain a uniformly dispersed dispersion liquid; then add 5 g of methylphenyl polysiloxane resin to the above-mentioned dispersion liquid, and stir with a magnetic stirrer to completely dissolve the acrylic acid-modified polysiloxane resin to obtain acrylic acid residual carbon composite graphene electrothermal coating.

[0069] Example 4

[0070] The preparation method of the acrylic acid residual carbon composite graphene electrothermal coating provided in this example includes the following steps:

[0071] Weigh 10 g of graphene (the ratio of the intensity of the D peak to the intensity of the G peak in the Raman spectrum ≤ 1 / 10; the molar ratio of silicon oxygen to carbon ≤ 1 / 20) and 6 g of acrylic acid-modified polysiloxane resin (Beilongsheng Sihai New Materials Co., Ltd., SH-024) respectively. After mechanical grinding, a composite material is obtained. The composite material is placed in a muffle furnace and sintered for the first time at 210 °C for 4 h in an air atmosphere, and then sintered for the second time at 600 °C for 30 min to obtain acrylic acid residual carbon composite graphene;

[0072] Add 2 g of polyvinylpyrrolidone K30 to 200 g of N-methylpyrrolidone, place it in a disperser for stirring and dispersion. After complete dissolution, add 10 g of the above-mentioned acrylic acid residual carbon composite graphene while stirring, and add 6 g of hexagonal boron nitride with a particle size D50 of 17 - 22 μm. After high-speed stirring and dispersion for 30 min, it is put into a sand mill. The rotation speed of the sand mill is set at 2300 rpm, and high-speed grinding and dispersion are carried out for 4 h to obtain a uniformly dispersed dispersion liquid; then add 7 g of epoxy-modified silicone resin to the above-mentioned dispersion liquid, and stir with a magnetic stirrer to completely dissolve the acrylic acid-modified polysiloxane resin to obtain acrylic acid residual carbon composite graphene electrothermal coating.

[0073] Comparative Example 1

[0074] The preparation method of the electrothermal coating provided in this comparative example refers to Example 1, with the only difference being that the acrylic residue carbon composite graphene is replaced by graphene (the ratio of the intensity of the D peak to the intensity of the G peak in the Raman spectrum ≤ 1 / 10; the molar ratio of stone oxygen to carbon ≤ 1 / 20).

[0075] Comparative Example 2

[0076] The preparation method of the electrothermal coating provided in this comparative example refers to Example 1, with the only difference being that the temperature of the first sintering is 180 °C.

[0077] Comparative Example 3

[0078] The preparation method of the electrothermal coating provided in this comparative example refers to Example 1, with the only difference being that the temperature of the first sintering is 260 °C.

[0079] Comparative Example 4

[0080] The preparation method of the electrothermal coating provided in this comparative example refers to Example 1, with the only difference being that hexagonal boron nitride is not added.

[0081] Test Example

[0082] The electrothermal coatings of Examples 1 to 4 and Comparative Examples 1 to 4 were respectively used to prepare electrothermal coatings according to the following method: Select a 100 mm × 100 mm × 1 mm quartz glass as the substrate, wipe the substrate with alcohol to remove the dirt on the surface, and dry it for standby; Coat the electrothermal coating onto the quartz glass substrate by the coating method, then put it into an oven and dry it at 90 °C for 2 h to preliminarily cure the coating, forming a coating with a length × width × thickness of 100 mm × 60 mm × 60 μm. Scrape and coat low-temperature conductive silver paste on both sides of the coating along the length direction as electrodes, and then put it into a muffle furnace again and sinter it at 600 °C for 30 min to completely cure the coating and the silver paste electrodes, obtaining the electrothermal coating.

[0083] The room temperature resistivity, electrothermal performance, adhesion, and aging resistance of each electrothermal coating were tested, and the results are shown in Table 1.

[0084] Room temperature resistivity: Measured by an ST2263 double-electrode digital four-probe tester;

[0085] Electrothermal performance: Connect the coating electrodes with a high-precision DC regulated power supply, apply 15 V, 18 V, 21 V, and 24 V respectively, and record the change of the average surface temperature of the coating with time and the stable electrothermal temperature after the voltage is connected through a Golde infrared thermal imager;

[0086] Adhesion: Conducted in accordance with GB / T 9286-1998;

[0087] Aging resistance performance: According to GB / T 1735-2009, the aging resistance test of the specimen was carried out by baking it in a muffle furnace at 400 °C for 48 h.

[0088] Table 1

[0089]

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An acrylic residual carbon composite graphene electric heating paint, characterized in that: According to the mass percentage, it includes the following components: 1 part of acrylic acid residual carbon composite graphene, 0.4-1 part of hexagonal boron nitride, 0.4-1.5 parts of binder, 0.1-0.5 parts of dispersant and 20-100 parts of solvent; The acrylic acid residual carbon composite graphene is mainly obtained by grinding and sintering graphene and acrylic acid modified polysiloxane resin in sequence.

2. The acrylic residual carbon composite graphene electric heating paint according to claim 1, characterized in that: The sintering comprises: performing a first sintering at 200-250° C. for 2-4 hours, and then performing a second sintering at 595-605° C. for 25-35 minutes.

3. The acrylic residual carbon composite graphene electric heating paint according to claim 1, characterized in that: The mass ratio of the graphene to the acrylic modified polysiloxane resin is 1:(0.6-0.8).

4. The acrylic residual carbon composite graphene electric heating paint according to claim 1, characterized in that: In the Raman spectrum of the graphene, the ratio of the D peak intensity to the G peak intensity is ≤1 / 10; in the graphene, the molar ratio of oxygen to carbon is ≤1 / 20.

5. The acrylic residual carbon composite graphene electric heating paint according to claim 1, characterized in that: The viscosity of the acrylic modified polysiloxane resin is 30 to 80 seconds when the solid content is 50%.

6. The acrylic residual carbon composite graphene electric heating paint according to claim 1, characterized in that: The particle size D50 of the hexagonal boron nitride is 17-22 μm.

7. The acrylic residual carbon composite graphene electric heating paint according to claim 1, characterized in that: The binder includes at least one of methylphenyl silicone resin, methylphenyl polysiloxane resin, acrylic modified polysiloxane resin and epoxy modified silicone resin.

8. The acrylic residual carbon composite graphene electric heating paint according to claim 1, characterized in that: The dispersant includes polyvinyl pyrrolidone K30; And / or, the solvent comprises N-methylpyrrolidone.

9. The method for preparing the acrylic residual carbon composite graphene electric heating coating according to any one of claims 1 to 8, characterized in that: The following steps are involved: The components are mixed evenly to obtain the acrylic acid residual carbon composite graphene electric heating paint.

10. The method for preparing the acrylic acid residual carbon composite graphene electric heating paint according to claim 9, characterized in that: The following steps are involved: The solvent, the dispersant, the acrylic acid residual carbon composite graphene and the hexagonal boron nitride are mixed to obtain a dispersion liquid; the dispersion liquid and the binder are mixed to obtain the acrylic acid residual carbon composite graphene electric heating paint.

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