Preparation method of laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating

Abstract

The present invention discloses a method for preparing a laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating, which belongs to the technical field of preparation of anti-icing materials. The laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating of the present invention includes a super-hydrophobic graphene coating and an electrically heated graphene coating; wherein, the super-hydrophobic graphene coating is obtained by laser engraving using polytetrafluoroethylene as a precursor material; and the electrically heated graphene coating is obtained by laser engraving using polyimide as a precursor material. The laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating of the present invention has wide adaptability, high reliability, good flexibility and adhesiveness, is not only suitable for any flat or curved substrate material, but also has good anti-icing reliability, and can accurately control its surface temperature to cope with different environments by adjusting the input power. Therefore, the composite anti-icing coating of the present invention has good application prospects in the field of anti-icing.

Description

Technical Field

[0001] The present invention relates to the technical field of preparation of anti-icing materials, and in particular to a method for preparing a laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating. Background Art

[0002] Icing is a common natural phenomenon, often seen in some areas due to factors such as weather conditions, temperature, humidity, topography, and circulation. It can cause significant inconvenience in daily life and industrial production, and can even lead to disasters or accidents. Especially in the aviation industry, ice accumulation on aircraft surfaces can reduce aerodynamic performance and maneuverability. Icing on sensors can cause them to malfunction, preventing accurate flight parameters from being obtained. Engine icing can also cause malfunctions, leading to accidents.

[0003] In order to avoid the various adverse effects caused by the icing phenomenon, scholars at home and abroad have explored many anti-icing methods. Among them, the electric heating method converts electrical energy into thermal energy to prevent ice formation or melt the ice layer. This method has a simple structure, strong controllability and does not produce pollution. It is a highly reliable anti-icing method. However, in order to achieve the ideal anti-icing effect, the electric heating system is usually required to maintain a long-term working state, which has the disadvantage of high energy consumption in actual application. On the other hand, the superhydrophobic anti-icing method uses a superhydrophobic surface to make it difficult for droplets to adhere, thereby preventing ice formation, delaying ice formation or reducing ice adhesion strength. However, in real environments, environmental factors such as low temperature, high humidity, and high wind speed will greatly reduce its hydrophobicity, and lose its anti-icing ability under dynamic conditions, which also limits the application of the superhydrophobic anti-icing method.

[0004] Therefore, combining an electric heating system with a superhydrophobic system to create a composite anti-icing system is expected to address these issues. However, existing composite anti-icing systems typically use metal electric heating elements placed internally. Due to the poor thermal conductivity of composite materials and the different physical and chemical properties of metals and composites, the two are mismatched, incompatible, and ineffective. Furthermore, existing composite anti-icing systems are complex to manufacture, cost-intensive, and difficult to implement, limiting their further application. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for preparing a laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] One of the technical solutions of the present invention: a laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating, wherein the composite anti-icing coating comprises a super-hydrophobic graphene coating and an electrically heated graphene coating;

[0008] The super-hydrophobic graphene coating is obtained by laser engraving using polytetrafluoroethylene (PTFE) as a precursor material; the electrically heated graphene coating is obtained by laser engraving using polyimide (PI) as a precursor material.

[0009] Technical solution 2 of the present invention: A method for preparing the above-mentioned laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating comprises the following steps:

[0010] Laser engraving of polytetrafluoroethylene and polyimide to obtain superhydrophobic graphene coating and graphene coating respectively;

[0011] Electrodes are arranged on the graphene coating to obtain an electrically heated graphene coating, and then a layer of adhesive is laid on the upper and lower surfaces of the electrically heated graphene coating. The adhesive layer on the upper surface is then bonded to the super-hydrophobic graphene coating to obtain the laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating.

[0012] Furthermore, the laser used in the laser engraving is a blue laser with a wavelength of 450 nm; and the focal mode used in the laser engraving is a focus mode or a defocus mode.

[0013] Furthermore, the power of the laser engraving is 0.1-10W, and the scanning rate is 12-120 mm / s.

[0014] Furthermore, the power of laser engraving on polytetrafluoroethylene is 2 to 5 W, and the scanning rate is 24 to 120 mm / s.

[0015] Furthermore, the laser engraving power for polytetrafluoroethylene was 2W and the scanning speed was 72 mm / s.

[0016] Furthermore, the power of laser engraving on polyimide is 2 to 4 W, and the scanning rate is 24 to 120 mm / s.

[0017] Furthermore, the laser engraving power for polyimide was 3 W and the scanning speed was 72 mm / s.

[0018] Furthermore, main components of the adhesive layer include acrylate and epoxy resin.

[0019] Furthermore, the cleaning is performed with deionized water for 5 to 10 minutes.

[0020] The third technical solution of the present invention: an application of the above-mentioned laser-induced graphene super-hydrophobic-electric heating composite anti-icing coating in the anti-icing field.

[0021] Furthermore, the application method specifically includes: bonding the laser-induced graphene super-hydrophobic-electric heating composite anti-icing coating to a base material, and connecting the electrode to a power supply.

[0022] Furthermore, the substrate material includes a flat or curved material; the material includes wood, metal, glass or a composite material board.

[0023] The present invention discloses the following technical effects:

[0024] (1) The laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating of the present invention has wide adaptability, high reliability, good flexibility and adhesiveness. It is not only suitable for substrate materials of any flat or curved surface, but also has good anti-icing reliability. By adjusting the input power, its surface temperature can be precisely controlled to cope with different environments. Therefore, the composite anti-icing coating of the present invention has good application prospects in the field of anti-icing.

[0025] (2) The laser-induced graphene super-hydrophobic-electric heating composite anti-icing coating (composite coating) of the present invention solves the problem that super-hydrophobic materials are prone to failure under actual working conditions and have poor anti-icing effect under dynamic conditions, thereby improving the effectiveness and reliability of anti-icing. Compared with the electric heating coating, the composite coating utilizes the characteristics of the surface super-hydrophobic layer to reduce ice accumulation and reduce ice adhesion, thereby reducing the deicing time and significantly reducing energy consumption during use. Therefore, compared with the two existing anti-icing methods, the composite anti-icing coating combines the advantages of the super-hydrophobic coating in reducing ice accumulation and reducing adhesion with the electric heating coating in anti-icing reliability, making up for the shortcomings of the super-hydrophobic coating in being prone to failure and the electric heating coating in consuming too much energy, and having more excellent performance.

[0026] (3) The composite coating of the present invention is mainly composed of a super-hydrophobic coating and an electric heating coating, both of which are graphene coatings prepared by laser induction. The preparation method is simple, efficient, low-cost, and environmentally friendly. By changing the precursor material and adjusting the laser parameters, graphene with different properties can be flexibly prepared. It has good designability and compatibility, and solves the problems of the existing composite anti-icing system, such as complex process, poor compatibility, and difficulty in implementation. In addition, the laser-induced graphene prepared by the present invention using PTFE as a precursor has better super-hydrophobic properties than ordinary graphene (graphene coating obtained by laser engraving polyimide). BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 The laser scanning pattern used in the present invention;

[0029] Figure 2 Raman spectra of the polytetrafluoroethylene film (PTFE) as the precursor material used in Example 1 of the present invention and the laser-induced graphene superhydrophobic coating (F-LIG) prepared in step (2);

[0030] Figure 3 Raman spectra of the polyimide film (PI) used as the precursor material in Example 1 of the present invention and the laser-induced graphene coating (PI-LIG) prepared in step (3);

[0031] Figure 4 The rolling angle of the laser-induced graphene super-hydrophobic coating prepared at different laser powers and different laser scanning rates in Example 2 of the present invention;

[0032] Figure 5 The contact angles of the polytetrafluoroethylene film (PTFE) used as the precursor material in Example 2 of the present invention and the laser-induced graphene superhydrophobic coating (F-LIG) prepared in Example 2;

[0033] Figure 6 The contact angle of the laser-induced graphene superhydrophobic coating (F-LIG) prepared in Example 2 of the present invention at a laser power of 2 W and a laser scanning rate of 72 mm / s changes with the number of freeze-thaw cycles;

[0034] Figure 7 The contact angle of the laser-induced graphene coating (PI-LIG) prepared in Example 3 of the present invention;

[0035] Figure 8 The resistance of the laser-induced graphene coating (PI-LIG) prepared in Example 3 of the present invention;

[0036] Figure 9 Graph showing temperature variation over time of a laser-induced graphene coating (PI-LIG) prepared in Example 3 of the present invention at different input voltages when the laser power is 3 W and the laser scanning rate is 72 mm / s;

[0037] Figure 10Schematic diagram of the structure of a material having a laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating prepared in Example 4 of the present invention, wherein 1 is a laser-induced graphene super-hydrophobic coating, 2 and 5 are both adhesive layers, 3 is an electrode that can be connected to a power supply, 4 is a laser-induced graphene coating, and 6 is a substrate material;

[0038] Figure 11 This is an infrared thermal image of a common commercially available polyimide metal electric heater after power is applied;

[0039] Figure 12 This is an infrared thermal image of the composite coating prepared in Example 4 of the present invention after being energized;

[0040] Figure 13 This is a comparative graph of the deicing time of the laser-induced graphene electric heating coating (PI-LIG Electricheating coating) prepared in Comparative Example 1 of the present invention and the laminated coating prepared in Example 4 under different input voltages;

[0041] Figure 14 This is a comparison chart of the dynamic anti-icing effects of the laser-induced graphene super-hydrophobic coating (super-hydrophobic coating) prepared in Comparative Example 2 of the present invention and the composite coating prepared in Example 4 under a simulated real icing environment;

[0042] Figure 15 A graph showing the change in ice mass of the laser-induced graphene electric heating coating (PI-LIG Electricheating coating) prepared in Comparative Example 1 of the present invention and the laminated coating prepared in Example 4 under simulated real icing conditions as the electric heating power changes. DETAILED DESCRIPTION

[0043] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0044] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0045] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0046] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the present invention. The present description and examples are intended to be illustrative only.

[0047] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0048] The laser scanning patterns used in the following embodiments and comparative examples of the present invention may be pictures or texts.

[0049] Example 1

[0050] Preparation of laser-induced graphene superhydrophobic coating (F-LIG) and laser-induced graphene coating (PI-LIG):

[0051] (1) A polytetrafluoroethylene film (PTFE) and a polyimide film (PI) were respectively cleaned with deionized water for 10 minutes and then dried to obtain cleaned polytetrafluoroethylene film (PTFE) and polyimide film (PI).

[0052] (2) Design the required laser scanning pattern (a 1.5 cm × 1.5 cm square black pattern), connect the computer to the laser, and import the pattern into the laser (a blue laser with a wavelength of 450 nm); place the cleaned polytetrafluoroethylene film into the laser engraving machine, adjust the upper and lower positions of the laser, and use the focus mode (focal length of 45 mm, spot size of 60 μm); select the preview option on the computer side and adjust the material position (the position shown in the preview should all be on the surface of the precursor material); set the scanning direction (unidirectional), laser power (3 W) and laser scanning rate (48 mm / s) on the computer side, and laser process the polytetrafluoroethylene film (laser engraving once) to obtain laser-induced graphene; place the obtained laser-induced graphene in a vacuum drying oven and dry it at 80 ° C for 2 h, then take it out to obtain a laser-induced graphene superhydrophobic coating (F-LIG).

[0053] (3) Design the required laser scanning pattern (a 1.5 cm × 1.5 cm square black pattern), connect the computer to the laser, and import the pattern into the laser (a blue laser with a wavelength of 450 nm); place the cleaned polyimide film into the laser engraving machine, adjust the upper and lower positions of the laser, and use the focus mode (focal length of 45 mm, spot size of 60 μm); select the preview option on the computer and adjust the material position (the position shown in the preview should all be on the surface of the precursor material); set the scanning direction (unidirectional), laser power (2 W) and laser scanning rate (60 mm / s) on the computer, and laser process the polyimide film (laser engrave once) to obtain laser-induced graphene; place the obtained laser-induced graphene in a vacuum drying oven and dry it at 80 ° C for 2 h, then take it out to obtain a laser-induced graphene coating (PI-LIG).

[0054] The laser scanning pattern used in this embodiment is shown in FIG. Figure 1 .

[0055] The Raman spectra of the precursor material polytetrafluoroethylene film (PTFE) used in this embodiment and the laser-induced graphene super-hydrophobic coating (F-LIG) prepared in step (2) are shown in FIG. Figure 2 .

[0056] from Figure 2 It can be seen that after laser treatment, PTFE produces obvious D peak, G peak and 2D peak, which verifies the formation of graphene.

[0057] The Raman spectra of the precursor material polyimide film (PI) used in this embodiment and the laser-induced graphene coating (PI-LIG) prepared in step (3) are shown in FIG. Figure 3 .

[0058] from Figure 3 It can be seen that after laser treatment, PI produces obvious D peak, G peak and 2D peak, which verifies the formation of graphene.

[0059] Example 2

[0060] Preparation of laser-induced graphene superhydrophobic coating (F-LIG):

[0061] (1) The polytetrafluoroethylene film (PTFE) was washed with deionized water for 10 minutes and then dried to obtain a cleaned polytetrafluoroethylene film (PTFE).

[0062] (2) Design the required laser scanning pattern (1.5cm×1.5cm square black pattern, see Figure 1), connect the computer to the laser, and import the pattern into the laser (blue light laser with a wavelength of 450nm); place the cleaned polytetrafluoroethylene film into the laser engraving machine, adjust the up and down position of the laser, and use the focus mode (focal length of 45mm, spot size of 60μm); select the preview option on the computer side, adjust the material position (the position shown in the preview should all be on the surface of the precursor material); set the scanning direction (unidirectional), laser power (2W, 3W and 4W respectively) and laser scanning rate (24mm / s, 48mm / s, 72mm / s, 96mm / s, 120mm / s respectively) on the computer side, laser treat the polytetrafluoroethylene film (laser engrave once) to obtain 15 types of laser-induced graphene; the obtained laser-induced graphene was placed in a vacuum drying oven and dried at 80℃ for 2h, and then taken out to obtain 15 types of laser-induced graphene superhydrophobic coatings (F-LIG).

[0063] The rolling angle of the laser-induced graphene super-hydrophobic coating prepared in this embodiment was measured. The results are shown in FIG. Figure 4 .

[0064] from Figure 4 It can be seen that when the laser power is 2W and the laser scanning rate is 72mm / s, the prepared graphene coating has the smallest rolling angle of 1.58°.

[0065] The contact angles (water contact angles) of the precursor material polytetrafluoroethylene film (PTFE) and the laser-induced graphene super-hydrophobic coating (F-LIG) prepared in this embodiment were measured. The results are shown in FIG. Figure 5 .

[0066] from Figure 5 As can be seen in the figure, the contact angle of the laser-induced graphene superhydrophobic coating (F-LIG) produced after laser induction is significantly improved compared to the precursor material PTFE. At a laser power of 2W and a laser scanning rate of 48mm / s, the contact angle of the laser-induced graphene superhydrophobic coating (F-LIG) is the highest, at 161.2°. At a laser power of 2W and a laser scanning rate of 72mm / s, the contact angle of F-LIG is 160.9°.

[0067] Combine Figure 4 and Figure 5 It can be found that when the laser power is 2W and the laser scanning rate is 72mm / s, the prepared laser-induced graphene superhydrophobic coating (F-LIG) has a sliding angle of 1.58° and a contact angle of 160.9°, showing the best hydrophobicity.

[0068] The contact angle of the laser-induced graphene super-hydrophobic coating (F-LIG) prepared in this embodiment was measured with a laser power of 2 W and a laser scanning rate of 72 mm / s as the number of freeze-thaw cycles increased. The results are shown in FIG. Figure 6 .

[0069] from Figure 6 It can be seen that the contact angle of the laser-induced graphene superhydrophobic coating (F-LIG) prepared at a laser power of 2 W and a laser scanning rate of 72 mm / s is still greater than 150° after 50 freeze-thaw cycles.

[0070] Example 3

[0071] Preparation of laser-induced graphene coating (PI-LIG):

[0072] (1) The polyimide film (PI) was washed with deionized water for 10 minutes and then dried to obtain a washed polyimide film (PI).

[0073] (2) Design the required laser scanning pattern (1.5cm×1.5cm square black pattern, see Figure 1 ), connect the computer and the laser, import the pattern into the laser (blue light laser with a wavelength of 450nm); place the cleaned polyimide film into the laser engraving machine, adjust the up and down position of the laser, and use the focus mode (focal length of 45mm, spot size of 60μm); select the preview option on the computer side, adjust the material position (the position shown in the preview should all be on the surface of the precursor material); set the scanning direction (unidirectional), laser power (2W, 3W, 4W, 5W respectively) and laser scanning rate (72mm / s, 84mm / s, 96mm / s, 108mm / s, 120mm / s) on the computer side, laser process the polyimide film (laser engrave once), and obtain 20 types of laser-induced graphene; the obtained laser-induced graphene is placed in a vacuum drying oven and dried at 80℃ for 2h, and then taken out to obtain 20 types of laser-induced graphene coatings (PI-LIG).

[0074] Since the laser-induced graphene coating (PI-LIG) prepared with PI as the precursor material has a pinning effect, water droplets attached to its surface cannot roll, so there is no rolling angle data for the laser-induced graphene coating (PI-LIG) group.

[0075] The contact angle of the laser-induced graphene coating (PI-LIG) prepared in this example was measured. Figure 7 .

[0076] from Figure 7It can be seen that the contact angle of the laser-induced graphene coating (PI-LIG) prepared with PI as the precursor exceeds 150° when the laser power is 5 W and the laser scanning rate is 120 mm / s.

[0077] The resistance of the laser-induced graphene coating (PI-LIG) prepared in this example was measured, and the results are shown in FIG. Figure 8 .

[0078] from Figure 8 It can be seen that the resistance of the laser-induced graphene coating prepared with PI as the precursor at a laser power of 3 W and a laser scanning rate of 72 mm / s is as low as 9 Ω / cm. Therefore, the electric heating performance of the laser-induced graphene coating prepared under this condition is the best.

[0079] The temperature of the laser-induced graphene coating (LIG) prepared in this embodiment was measured with a laser power of 3W and a laser scanning rate of 72mm / s. The results are shown in Figure 9 .

[0080] from Figure 9 As can be seen in the figure, the surface temperature of the laser-induced graphene coating (PI-LIG) prepared at a laser power of 3W and a laser scanning rate of 72mm / s rises rapidly after power is applied, then gradually decreases, eventually reaching an equilibrium temperature. Therefore, the equilibrium temperature can be precisely controlled by varying the input voltage. At an input voltage of 7V, the equilibrium temperature of 236°C is reached in just 60 seconds and remains stable for a long time, meeting the performance requirements of the electrically heated coating in the composite anti-icing coating.

[0081] Example 4

[0082] A method for preparing a laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating:

[0083] (1) A polytetrafluoroethylene film (PTFE) and a polyimide film (PI) were respectively cleaned with deionized water for 10 minutes and then dried to obtain cleaned polytetrafluoroethylene film (PTFE) and polyimide film (PI).

[0084] (2) Design the required laser scanning pattern (1.5cm×1.5cm square black pattern, see Figure 1), connect the computer and the laser, import the pattern into the laser (blue light laser with a wavelength of 450nm); place the cleaned polytetrafluoroethylene film into the laser engraving machine, adjust the up and down position of the laser, and use the focus mode (focal length of 45mm, spot size of 60μm); select the preview option on the computer side, adjust the material position (the position shown in the preview should all be on the surface of the precursor material); set the scanning direction (unidirectional), laser power (2W) and laser scanning rate (72mm / s) on the computer side, laser process the polytetrafluoroethylene film (laser engrave once) to obtain laser-induced graphene; put the obtained laser-induced graphene into a vacuum drying oven and dry it at 80℃ for 2h, then take it out to obtain a laser-induced graphene superhydrophobic coating (F-LIG).

[0085] (3) Design the required laser scanning pattern (1.5cm×1.5cm square black pattern, see Figure 1 ), connect the computer and the laser, import the pattern into the laser (blue light laser with a wavelength of 450nm); place the cleaned polyimide film into the laser engraving machine, adjust the up and down position of the laser, and use the focus mode (focal length of 45mm, spot size of 60μm); select the preview option on the computer side, adjust the material position (the position shown in the preview should all be on the surface of the precursor material); set the scanning direction (unidirectional), laser power (3W) and laser scanning rate (72mm / s) on the computer side, laser process the polyimide film (laser engrave once) to obtain laser-induced graphene; put the obtained laser-induced graphene into a vacuum drying oven and dry it at 80℃ for 2h, then take it out to obtain a laser-induced graphene coating (PI-LIG).

[0086] (4) Copper sheets were added as electrodes at the left and right ends of the laser-induced graphene coating (PI-LIG) prepared in step (3), and bonded with conductive silver glue (CD-03, Guangzhou Kaixiang Electronic Products Co., Ltd.) to obtain a laser-induced graphene electric heating coating with a unit length resistance of 9 Ω / cm.

[0087] (5) A layer of conductive silver glue is laid on the upper and lower surfaces of the laser-induced graphene electric heating coating, and then the glue layer on the upper surface is bonded to the laser-induced graphene super-hydrophobic coating to obtain a laser-induced graphene super-hydrophobic-electric heating composite anti-icing coating (composite coating).

[0088] The adhesive layer on the lower surface of the laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating is bonded to a base material, and the electrodes are connected to the positive and negative poles of a power supply to obtain a material having a laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating.

[0089] The structural diagram of the material with laser-induced graphene super-hydrophobic-electric heating composite anti-icing coating prepared in this embodiment is shown in FIG. Figure 10 . Figure 10 In the figure, 1 is a laser-induced graphene super-hydrophobic coating, 2 and 5 are adhesive layers, 3 is an electrode that can be connected to a power supply, 4 is a laser-induced graphene coating, and 6 is a base material; 3 and 4 constitute a laser-induced graphene electric heating coating.

[0090] The infrared thermal imaging images of the common commercially available polyimide metal electric heating sheet (Sheng Berlin Rubber & Plastic Electronics Co., Ltd.) and the composite coating prepared in this embodiment after being energized are shown in the following figure. Figure 11 and Figure 12 .

[0091] Figure 11 This is an infrared thermal image of a common commercially available polyimide metal electric heater after power is applied; Figure 12 This is an infrared thermal imaging image of the composite coating prepared in this embodiment after being energized.

[0092] from Figure 11 and Figure 12 It can be seen that compared with the common commercially available polyimide metal electric heating sheet, the temperature distribution of the composite coating prepared in this embodiment after power is applied has better uniformity and consistency.

[0093] Comparative Example 1

[0094] Preparation of laser-induced graphene electric heating coating:

[0095] (1) The polyimide film (PI) was washed with deionized water for 10 minutes and then dried to obtain a washed polyimide film (PI).

[0096] (2) Design the required laser scanning pattern (1.5cm×1.5cm square black pattern, see Figure 1 ), connect the computer and the laser, import the pattern into the laser (blue light laser with a wavelength of 450nm); place the cleaned polyimide film into the laser engraving machine, adjust the up and down position of the laser, and use the focus mode (focal length of 45mm, spot size of 60μm); select the preview option on the computer side, adjust the material position (the position shown in the preview should all be on the surface of the precursor material); set the scanning direction (unidirectional), laser power (3W) and laser scanning rate (72mm / s) on the computer side, laser process the polyimide film (laser engrave once) to obtain laser-induced graphene; put the obtained laser-induced graphene into a vacuum drying oven and dry it at 80℃ for 2h, then take it out to obtain a laser-induced graphene coating (PI-LIG).

[0097] (3) Copper sheets were added as electrodes at the left and right ends of the laser-induced graphene coating (PI-LIG) prepared in step (3), and bonded with conductive silver glue to obtain a laser-induced graphene electric heating coating with a unit length resistance of 9 Ω / cm.

[0098] Comparative Example 2

[0099] Preparation of a laser-induced graphene super-hydrophobic coating:

[0100] (1) The polytetrafluoroethylene film (PTFE) was washed with deionized water for 10 minutes and then dried to obtain a cleaned polytetrafluoroethylene film (PTFE).

[0101] (2) Design the required laser scanning pattern (1.5cm×1.5cm square black pattern, see Figure 1 ), connect the computer and the laser, import the pattern into the laser (blue light laser with a wavelength of 450nm); place the cleaned polytetrafluoroethylene film into the laser engraving machine, adjust the up and down position of the laser, and use the focus mode (focal length is 45mm, spot size is 60μm); select the preview option on the computer side, adjust the material position (the position shown in the preview should all be on the surface of the precursor material); set the scanning direction (unidirectional), laser power (2W) and laser scanning rate (72mm / s) on the computer side, laser process the polytetrafluoroethylene film (laser engrave once) to obtain laser induced graphene; put the obtained laser induced graphene into a vacuum drying oven and dry it at 80℃ for 2h, then take it out to obtain a laser induced graphene super hydrophobic coating.

[0102] Effect Example 1

[0103] The deicing time of the laser-induced graphene electric heating coating (electric heating coating) prepared in Comparative Example 1 and the composite coating prepared in Example 4 was measured at different input voltages. The results are shown in FIG. Figure 13 .

[0104] The test method is as follows: the coatings prepared in Comparative Example 1 and Example 4 are placed in an environment at -15°C with a volume of 1 cm 3 After the cubes of ice were frozen for the same time, the electrodes with the two coatings were connected to the positive and negative poles of the power supply, and the deicing time was measured at different voltages.

[0105] from Figure 13As can be seen from the results, under different voltages, the deicing time of the composite coating (laminated coating) prepared in Example 4 is reduced compared to the laser-induced graphene electric heating coating (PI-LIG Electric Heating Coating, hereinafter referred to as the electric heating coating) prepared in Comparative Example 1, and the deicing time shows a negative correlation with the input voltage. When the input voltage is 10V, the deicing time of the composite coating prepared in Example 4 is shortened from 80s to 41s compared to the laser-induced graphene electric heating coating prepared in Comparative Example 1. Therefore, under the conditions of the same voltage, the same resistance, and the same power-on time, it can be seen from Joule's formula that ice cubes of the same size can be completely deiced. The composite coating prepared in Example 4 can save 48.75% energy compared to the laser-induced graphene electric heating coating prepared in Comparative Example 1.

[0106] Effect Example 2

[0107] The dynamic anti-icing effect of the laser-induced graphene super-hydrophobic coating (super-hydrophobic coating) prepared in comparative example 2 and the composite coating prepared in example 4 was measured in a simulated real icing environment. The results are shown in FIG. Figure 14 .

[0108] The test method is as follows: place the super hydrophobic coating in a temperature of -30°C, a wind speed of 20m / s, an average water droplet diameter of 50μm, and a liquid water content of 1g / m 3 Maintain for 1 min under the conditions.

[0109] The composite coating was placed in a temperature of -30 ° C, a wind speed of 20 m / s, an average water droplet diameter of 50 μm, and a liquid water content of 1 g / m 3 The conditions were maintained for 1 min, during which the composite coating was electrically heated with an electric heating power of 13W.

[0110] from Figure 14 It can be seen that there is obvious icing on the surface of the superhydrophobic coating, while there are only tiny water droplets on the surface of the composite coating, showing good dynamic anti-icing performance.

[0111] Effect Example 3

[0112] The ice-covered mass changes of the composite coating (laminated coating) prepared in Example 4 of the present invention and the laser-induced graphene electric heating coating (PI-LIG Electric Heating Coating, referred to as the electric heating coating) prepared in Comparative Example 1 were measured with the electric heating power changing in a simulated real icing environment. The results are shown in FIG. Figure 15 .

[0113] The test method is as follows: place the composite coating and the electric heating coating in a temperature of -30°C, a wind speed of 20m / s, an average water droplet diameter of 50μm, and a liquid water content of 1g / m3 The conditions are maintained for 1 minute, during which the composite coating and the electric heating coating are electrically heated, and the voltage of the electric heating is 6 to 10V.

[0114] from Figure 15 As can be seen from the graph, when the voltage is less than 7V, the ice mass of the two coatings remains essentially unchanged. This is because when the electrical power is low, the sample surface temperature is far below 0°C, and no anti-icing effect can be achieved. When the voltage exceeds 7V, the ice mass of the two materials decreases linearly. When the voltage reaches 10V, the composite coating achieves complete anti-icing, and when the voltage reaches 11V, the electric heating coating achieves complete anti-icing. Calculations based on Joule's formula show that under given environmental conditions, the composite coating can achieve 17.36% energy savings compared to the electric heating coating in achieving complete anti-icing.

[0115] from Figures 13-15 It can be seen from the figure that, whether it is deicing or anti-icing, under the condition of the same anti-icing effect, the composite coating is more energy-efficient than the single electric heating coating. Figure 14 As can be seen from the figure, the anti-icing effect of the composite coating is much better than that of the super-hydrophobic coating alone. This shows that the composite coating prepared by the present invention can exhibit excellent anti-icing performance in actual working conditions and has good application prospects.

[0116] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating, characterized in that: The composite anti-icing coating includes a super-hydrophobic graphene coating and an electrically heated graphene coating; The super-hydrophobic graphene coating is obtained by laser engraving using polytetrafluoroethylene as a precursor material; the electrically heated graphene coating is obtained by laser engraving using polyimide as a precursor material; The method for preparing the laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating comprises the following steps: Laser engraving of polytetrafluoroethylene and polyimide to obtain superhydrophobic graphene coating and graphene coating respectively; Electrodes are arranged on the graphene coating to obtain an electrically heated graphene coating, and then a layer of adhesive is laid on the upper and lower surfaces of the electrically heated graphene coating, and then the adhesive layer on the upper surface is bonded to the super-hydrophobic graphene coating to obtain the laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating; The laser used in the laser engraving is a blue laser with a wavelength of 450nm; the focal mode used in the laser engraving is a focus mode or a defocus mode; When preparing the super-hydrophobic graphene coating, the laser engraving power is 2W and the scanning rate is 72mm / s; When preparing the electrically heated graphene coating, the power of the laser engraving is 3W and the scanning rate is 72 mm / s.

2. The laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating according to claim 1, characterized in that: Main components of the adhesive layer include acrylate and epoxy resin.

3. An application of the laser-induced graphene super-hydrophobic-electrically heated composite anti-icing coating according to claim 1 in the field of anti-icing.

4. The use according to claim 3, characterized in that The application method specifically includes: bonding the laser-induced graphene super-hydrophobic-electric heating composite anti-icing coating to a base material, and connecting an electrode to a power supply.

5. The use according to claim 4, characterized in that The substrate material includes a flat or curved material; the material includes wood, metal, glass or composite material board.

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