Low-power-consumption high-durability anti-icing composite material and forming method
By embedding a porous electrothermal film in the composite material and preparing a photothermal superhydrophobic coating, the problems of high power consumption and poor durability of anti-icing composite materials are solved, achieving low power consumption, high durability and self-cleaning anti-icing effect.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NAT UNIV OF DEFENSE TECH
- Filing Date
- 2023-01-16
- Publication Date
- 2026-06-19
AI Technical Summary
Existing anti-icing composite materials have high power consumption and poor durability, making them difficult to effectively prevent and remove ice under complex weather conditions.
Using a porous electrothermal film as a substrate, a photothermal superhydrophobic coating is prepared by wet air spraying. Combined with prepreg molding, a layered structure of multifunctional film and preform is formed. The electrothermal film is embedded on the surface of the composite material, integrating superhydrophobic and photothermal properties.
It achieves low power consumption, high durability, anti-icing and de-icing, high electrothermal efficiency, superhydrophobic coating to prevent icing, photothermal properties to delay icing, reduce energy consumption, avoid mechanical damage, and has a self-cleaning function.
Smart Images
Figure CN116353110B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of anti-icing and de-icing technology for small and medium-sized unmanned aerial vehicles and large civil passenger aircraft, and in particular to a low-power, high-durability anti-icing composite material and its molding method. Background Technology
[0002] Fiber-reinforced polymer composites (FRPCs) achieve material / structure integration and design / manufacturing integration by arranging reinforcing fibers in a specific pattern within a resin matrix and molding them under high temperature and pressure. Due to their high specific strength, high specific modulus, low processing cost, flexible performance design, and excellent corrosion and heat resistance, FRPCs have become widely used advanced basic materials and key strategic materials. While meeting the requirements of high-performance structural components for small and medium-sized UAVs and large civil aircraft, FRPCs also face harsh service environments. Meteorological data shows that the altitude at which icing is most likely to occur in China during spring, summer, autumn, and winter is between 3000 and 6000 meters. These altitudes basically cover the flight altitude range of all-weather UAVs. When aircraft fly in complex weather conditions, they may be affected by the impact of dynamically supercooled clouds or supercooled raindrops, resulting in icing problems that seriously affect flight safety.
[0003] Traditional anti-icing technologies such as liquid anti-icing, mechanical de-icing, thermal effect anti-icing (electric heating, hot gas), and electro-pulse de-icing, while increasingly mature, suffer from drawbacks such as complex structures and high energy consumption. Active electrothermal anti-icing technology is considered a good method due to its high heating efficiency, precise control, and flexible deployment. However, single electrothermal anti-icing systems are still plagued by power consumption issues. Furthermore, passive anti-icing methods do not require additional power, effectively reducing the energy consumption of active anti-icing technologies. Therefore, combining active and passive technologies is an effective way to achieve efficient anti-icing of resin-based composite materials. However, existing active and passive technologies still suffer from drawbacks such as high power consumption and poor durability. Summary of the Invention
[0004] This invention provides a low-power, high-durability anti-icing composite material and a molding method, which overcomes the defects of existing anti-icing composite materials such as high power consumption and poor durability.
[0005] To achieve the above objectives, this invention proposes a molding method for a low-power, high-durability anti-icing composite material, comprising the following steps:
[0006] S1: Using a porous electrothermal film as a substrate, a photothermal superhydrophobic coating is prepared by spraying a slurry onto the surface of the substrate through wet air spraying, thereby obtaining a multifunctional thin film;
[0007] S2: Select prepreg according to actual needs, and cut and lay up the prepreg in sequence to obtain the preform;
[0008] S3: The substrate of the multifunctional film is laid on the surface of the preform, and then cured to obtain a low-power, high-durability anti-icing composite material.
[0009] To achieve the above objectives, the present invention also proposes a low-power, high-durability anti-icing composite material, which is prepared and shaped by the molding method described above; the composite material has a layered structure and is composed of a multifunctional film and a preform; the multifunctional film is composed of a porous electrothermal film and a photothermal superhydrophobic coating; the substrate surface of the multifunctional film is laid on the surface of the preform.
[0010] To achieve the above objectives, the present invention also proposes an application of a low-power, high-durability anti-icing composite material, which applies the composite material prepared by the above molding method or the above composite material to equipment components such as aircraft skin and wind turbine blades in high-latitude regions.
[0011] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0012] 1. The molding method for the low-power, high-durability anti-icing composite material provided by this invention first uses a porous electrothermal film as a substrate. The surface of this porous electrothermal film has intrinsic micron-sized protrusions and micro / nano-sized pores, which can provide an intrinsic micro / nano-level structure for subsequent spraying, thus enriching the coating roughness. Furthermore, its intrinsic micro / nano-sized pores facilitate resin penetration into the porous electrothermal film, forming an anchoring structure similar to soil fixing "tree roots," which is beneficial for fixing the electrothermal film and the functional coating. This balances the roughness and robustness of the micro / nano-level structure. Then, during the prepreg molding process, a multifunctional film is laid on the surface of the preform. Under molding pressure, the resin in the prepreg penetrates and wets the electrothermal film effectively, firmly bonding it to the FRPC surface. Moreover, because the electrothermal film surface is pre-impregnated with a photothermal superhydrophobic coating, the resin in the prepreg will not flow to the surface of the photothermal superhydrophobic coating, ensuring that the surface structure and properties of the photothermal superhydrophobic coating remain unchanged after molding. This results in a dual impregnation of the porous electrothermal film with a photothermal superhydrophobic coating and resin, which helps to form a stable functional surface and significantly improves the durability of the composite material.
[0013] 2. Compared to the traditional method of embedding the electrothermal film within the composite material layup, the low-power, high-durability, anti-icing composite material molding method provided by this invention, in which the electrothermal film is embedded externally within the composite material, can produce the following beneficial effects: First, the embedded electrothermal film can quickly conduct electrothermal energy to the surface of the component to exert its effect; second, the embedded electrothermal film can integrate superhydrophobic and photothermal properties, further reducing electrothermal power consumption; third, the superhydrophobic surface energy can provide a good waterproof effect, avoiding the degradation of the heating characteristics of the electrothermal film and the performance of the resin-based composite material. Attached Figure Description
[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0015] Figure 1 This is a SEM image of the original porous electrothermal film screen-printed texture surface in Example 1; the upper right corner shows a magnified view of a portion of the image.
[0016] Figure 2 This is a SEM image of the multifunctional thin film in Example 1; the upper right corner shows a magnified view.
[0017] Figure 3 Figure 1 shows a cross-sectional SEM image of the low-power, high-durability, anti-icing composite material in Example 1; Figure 2a shows a schematic diagram of the resin bidirectional impregnation porous electrothermal film structure; Figure 3b is a cross-sectional SEM image of the composite material bidirectional impregnation porous electrothermal film; Figures 4c, 5d, and 6e are magnified images of positions 1, 2, and 3 in Figure 4b; Figure 7f is an EDS cross-sectional image of the composite material, characterizing the distribution of Fe elements in the multifunctional coating.
[0018] Figure 4 The images show the icing process on the surface of the low-power, high-durability anti-icing composite material in Example 1; where a is the initial water droplet image, b is the image of the surface becoming opaque after the water droplet has been frozen for 1009s, and c is the image of the water droplet being completely frozen after 1116s (the moment the spike above the water droplet appears indicates that icing is complete).
[0019] Figure 5 The images show the surface of the low-power, high-durability anti-icing composite material in Example 1, subjected to continuous high-speed water flow (5 m / s) for 11 min. In this image, a is the initial moment when the water just flows out of the pipe, and b, c, d, and e are images taken at times 00:00:20, 10:59:90, 11:00:17, and 12:00:30, respectively, relative to the initial moment.
[0020] Figure 6 The images are photographs of the icing process on the surface of the composite material in Comparative Example 1; where aa is the initial water droplet photograph, b is the photograph of the surface becoming opaque after the water droplet has frozen for 114 s, and c is the photograph of the water droplet being completely frozen after 180 s.
[0021] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0023] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.
[0024] Unless otherwise specified, all medicines / reagents used are commercially available.
[0025] This invention proposes a molding method for a low-power, high-durability anti-icing composite material, comprising the following steps:
[0026] S1: Using a porous electrothermal film as a substrate, a photothermal superhydrophobic coating is prepared by spraying a slurry onto the surface of the substrate through wet air spraying. The coating is anchored to the porous microstructure by the infiltration of wet droplets into the porous electrothermal film, resulting in a multifunctional thin film.
[0027] Porous electrothermal films are characterized by having micron-scale screen-printed or fiber structures on their surface.
[0028] Multifunctional thin films integrate superhydrophobicity, photothermal and electrothermal properties.
[0029] S2: Select a prepreg according to actual needs, and cut and lay up the prepreg in sequence to obtain a preform.
[0030] S3: The substrate of the multifunctional film is laid on the surface of the preform, and then cured to obtain a low-power, high-durability anti-icing composite material.
[0031] The molding and curing process can be achieved through compression molding, vacuum bag pressing, autoclave, etc.
[0032] The molding method provided by this invention yields a composite material with a multifunctional surface and a resin-based composite material surface possessing a bidirectional resin impregnation structure. This structure can anchor the electrothermal film and multifunctional coating, ensuring their firm adhesion to the composite material surface for effective operation. The superhydrophobic and photothermal surface effectively inhibits surface frosting, delays icing, and prevents secondary icing. Simultaneously, the electrothermal effect promotes ice melting, avoiding damage to the surface microstructure caused by mechanical de-icing. The two work synergistically to achieve a low-cost, low-power, highly durable, and self-cleaning anti-icing surface.
[0033] Preferably, the porous electrothermal film is a blend of organic fibers and conductive fillers, without the addition of binders, and is self-supported by the entanglement and hydrogen bonding between the fibers. The organic fibers can be various cellulose fibers, aramid fibers, etc. The conductive fillers can be carbon nanotubes, silver nanowires, graphene, etc.
[0034] Preferably, in step S1, a photothermal superhydrophobic coating is prepared by spraying the coating slurry onto the substrate surface using wet air spraying, and the specific process is as follows:
[0035] S11: Fe3O4 nanoparticles are soaked in a fluorosilane product solution to obtain modified Fe3O4.
[0036] S12: Select an epoxy resin and fluorinate it to obtain a modified epoxy resin.
[0037] S13: The modified Fe3O4 and multi-walled carbon nanotubes (MWCNTs) are mixed at a mass ratio of 1:1 to obtain blended particles;
[0038] Then, the modified epoxy resin, curing agent, organic solvent and blended particles are mixed and stirred to obtain a spraying slurry.
[0039] Organic solvents can be ethyl acetate, acetone, DMF, toluene, etc.
[0040] S14: The spray slurry is sprayed onto the substrate surface using a spray gun to prepare a photothermal superhydrophobic coating, which is then dried and cured to obtain a multifunctional film.
[0041] Preferably, in step S11, the mass ratio of the Fe3O4 nanoparticles to the fluorosilane solution is 1:20 to 100; the particle size of the Fe3O4 nanoparticles is 50 to 300 nm; the concentration of the fluorosilane product in the fluorosilane product solution is 1 to 10 wt%, and the fluorosilane product is at least one of fluorosilane, fluorochlorosilane, and perfluoropolyether silane; the soaking time is 12 to 36 h.
[0042] Preferably, in step S12, the epoxy resin is one or more of bisphenol A, bisphenol F, polyphenol, and aliphatic epoxy resins. The hydrophobic modification method is the method reported in patent 201910091634.5.
[0043] Preferably, in step S13, the ratio of the modified epoxy resin to the curing agent is determined according to the epoxy value of the epoxy resin and the type of curing agent in the industry; the mass ratio of the blended particles to the solvent is 1:50 to 150.
[0044] Preferably, in step S14, the spraying pressure is 0.2-1 MPa, the spraying distance is 5-15 cm, and the spraying amount is 1-5 wt% of the weight gain of the dried substrate.
[0045] Preferably, in step S14, the drying process involves placing the item in a 60°C oven and keeping it at that temperature for 10–30 minutes.
[0046] The curing procedure is determined based on the curing procedure of the selected epoxy resin.
[0047] Preferably, in step S3, the molding and curing regime is determined based on the resin curing regime in the prepreg.
[0048] Preferably, before prepreg molding, conductive silver paste is coated on both sides of the substrate of the multifunctional film to adhere conductive copper foil as electrodes for electric heating. In particular, a patch-type temperature sensor can also be adhered to the substrate to detect and regulate the surface temperature, and wires are led out from the side.
[0049] During the prepreg molding process, the prepreg is laid out according to certain specifications and sequence, and then an electrothermal film is laid on the surface. The edges of the electrothermal film are wrapped to prevent resin from seeping onto the multifunctional coating surface during curing.
[0050] This invention also proposes a low-power, high-durability anti-icing composite material, which is prepared and shaped by the molding method described above; the composite material has a layered structure and is composed of a multifunctional film and a preform; the multifunctional film is composed of a porous electrothermal film and a photothermal superhydrophobic coating; the substrate of the multifunctional film is laid on the surface of the preform.
[0051] This invention also proposes an application of a low-power, high-durability anti-icing composite material, in which the composite material prepared by the molding method described above or the composite material described above is applied to equipment components such as aircraft skin and wind turbine blades in high-latitude regions.
[0052] Example 1
[0053] This embodiment provides a molding method for a low-power, high-durability anti-icing composite material, including the following steps:
[0054] S1: Using a porous electrothermal film as a substrate, a photothermal superhydrophobic coating is prepared by spraying a slurry onto the surface of the substrate through wet air spraying. The coating is anchored to the porous microstructure by the infiltration of wet droplets into the porous electrothermal film, resulting in a multifunctional thin film.
[0055] The preparation of a photothermal superhydrophobic coating by spraying a slurry onto the substrate surface via wet air spraying specifically includes:
[0056] S11: Fe3O4 nanoparticles were soaked in 0.4wt% perfluoropolyether silane (OPtool UD509) for 1 hour, then filtered and dried to obtain hydrophobic modified Fe3O4.
[0057] S12: Epoxy resin E51 is fluorinated and modified according to the method described in the patent. The specific modification process is as follows: First, 112.95g KH560 and 12.78g of sodium hydroxide solution with a concentration of 0.01g / mL are dissolved in 60g ethanol and prepolymerized at 80℃ for 1h. Then, 67.05g FAS and 3.15g of sodium hydroxide with a concentration of 0.1g / mL are added, and the reaction is continued to be stirred for 3h. After the ethanol is distilled off, it is thoroughly stirred with 270g of epoxy E51 resin for later use.
[0058] S13: Take 0.2g each of modified Fe3O4 and MWCNT and mix them to obtain blended particles. Then mix them with modified epoxy resin (2.98g), curing agent polyetheramine D230 (1.02g), ethyl acetate (40g) and the above blended particles. After stirring thoroughly, a spraying slurry is obtained.
[0059] S14: Transfer the above slurry to a spray bottle and spray it with air at a pressure of 0.3 MPa, keeping a film-forming distance of 10 cm from the heating film. After spraying for 30 seconds, a multifunctional film is produced.
[0060] S2: Select a glass fiber plain weave prepreg according to the actual needs of the resin-based composite component. Cut the glass fiber plain weave prepreg and the multifunctional film into 4cm×6cm pieces and lay four such prepreg pieces in alignment. Attach 0.5cm wide conductive copper foil as electrodes to both sides of the multifunctional film substrate using conductive silver paste. Then, lay the multifunctional film on the surface of the preform (functional coating surface facing up) to obtain the preform.
[0061] S3: After sealing the above preform, use a vacuum pump to evacuate the vacuum, and keep it at 120°C for 2 hours to solidify and obtain a low-power, high-durability anti-icing composite material.
[0062] In this embodiment, the porous electrothermal film is prepared by blending multi-walled carbon nanotubes and aramid fibers, screen printing, and drying. Its characteristic is that the surface has a micron-scale screen-printed structure or fiber structure (such as...). Figure 1 (As shown). By Figure 1It can be seen that the original porous electrothermal film surface has a screen-printed texture structure, which is composed of crisscrossing MWCNTs and aramid fibers. After spraying, a film coated with a multifunctional coating is obtained. Figure 2 As shown, the textured structure is encapsulated by resin, forming a micro-nano hierarchical structure together with MWCNTs and nano-Fe3O4 nanoparticles. After preparing the multifunctional resin-based composite material using monolithic molding, its cross-section was characterized by SEM, as shown... Figure 3 As shown in Figure af, the resin-permeated structure is visible in the cross-sections. On the resin-based composite side, the resin encapsulation of the glass fibers is evident. Near the surface of the composite material ( Figure 3 In diagram b), the structure of resin-encapsulated MWCNTs and aramid fibers can be seen. This is a result of the resin in the prepreg permeating the porous electrothermal membrane under molding pressure. Figure 3 (cd). The infiltration of this resin can anchor the electrothermal film and enhance the bonding between the functional coating and the resin-based composite material. Furthermore, interfacial EDS analysis shows that ( Figure 3 In part f), Fe element is present on and near the surface, which proves the penetration of the sprayed coating onto the porous electrothermal film on the outer surface. From the above analysis, it can be seen that using the preparation method of this invention, the resin in the sprayed slurry and prepreg impregnates the porous electrothermal film from both sides, forming a unique... Figure 3 The bidirectional impregnation structure shown in Figure ab. This structure can anchor the electrothermal film and the multifunctional coating, synergistically achieving efficient and highly durable anti-icing and de-icing.
[0063] The anti-icing properties of the composite material surface prepared above were tested. During the test, the sample was placed on a cold stage at -15°C for 2 minutes to allow the surface temperature to equalize. Then, a drop of 20 μL of deionized water was placed on the surface, and the entire test environment was sealed to suppress condensation. The freezing process of the droplet was captured using a CCD camera. Figure 4 As shown, it took 1116 seconds for the water droplet to freeze completely.
[0064] Next, the durability of the multifunctional coating was tested, such as... Figure 5 As shown, the surface of the multifunctional resin-based composite material was rinsed with a tap under a water flow rate of ~5 m / s for ~11 minutes. The sample surface remained unchanged, and no water droplets adhered. This indicates that the multifunctional coating prepared by this invention has good durability and can meet the requirements of practical applications.
[0065] Example 2
[0066] This embodiment provides a molding method for a low-power, high-durability anti-icing composite material. The steps and process parameters are the same as in Embodiment 1, except that step S3 is replaced with a molding process. Specifically, the preform is placed in a hot press, gradually heated to 120 degrees Celsius, and then pressurized to 3 MPa. After holding at this temperature and pressure for 2 hours, the low-power, high-durability anti-icing composite material is obtained. This demonstrates that the method of this invention is applicable to different composite material molding processes.
[0067] Comparative Example 1
[0068] This comparative example uses the same steps and process parameters as Example 1, except that the porous electrothermal film in S1 is replaced with a commercially available graphene electrothermal film. Because this type of electrothermal film is formed by coating a mixture of conductive filler and resin (such as acrylic resin), the film is dense and non-porous with no surface texture. After integral molding, the electrothermal film and the resin-based composite material cannot form an anchoring structure, resulting in poor bonding. Furthermore, the lack of intrinsic texture on the surface of this electrothermal film leads to insufficient roughness in the resulting micro / nanostructure of the coating. Figure 6 As shown, under the same conditions as the freezing test in Example 1, the water droplets froze completely after only 180 seconds.
[0069] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.
Claims
1. A molding method of a low-power-consumption high-durability deicing composite material, characterized by, Includes the following steps: S1: Using a porous electrothermal film as a substrate, a photothermal superhydrophobic coating is prepared by spraying a slurry onto the surface of the substrate through wet air spraying. The coating is anchored to the porous microstructure by the infiltration of wet droplets into the porous electrothermal film, resulting in a multifunctional thin film. The porous electrothermal film is made of a blend of organic fibers and conductive fillers, without the addition of adhesives, and is self-supported by the entanglement and hydrogen bonding between the fibers. The specific process for preparing a photothermal superhydrophobic coating by spraying a slurry onto the substrate surface using wet air spraying is as follows: S11: Fe3O4 nanoparticles are soaked in a fluorosilane product solution to obtain modified Fe3O4; the mass ratio of Fe3O4 nanoparticles to fluorosilane solution is 1:20~100; the particle size of Fe3O4 nanoparticles is 50~300 nm; the concentration of fluorosilane product in the fluorosilane product solution is 1~10 wt%, and the fluorosilane product is at least one of fluorosilane, fluorochlorosilane, and perfluoropolyether silane; S12: Select an epoxy resin and fluorinate the epoxy resin to obtain a modified epoxy resin. S13: The modified Fe3O4 and multi-walled carbon nanotubes are mixed at a mass ratio of 1:1 to obtain blended particles; Then, the modified epoxy resin, curing agent, organic solvent, and blended particles are mixed and stirred to obtain a spraying slurry; the mass ratio of the blended particles to the organic solvent is 1:50~150. S14: The slurry is sprayed onto the substrate surface using a spray gun to prepare a photothermal superhydrophobic coating, which is then dried and cured to obtain a multifunctional film; the spraying pressure is 0.2~1 MPa, the spraying distance is 5~15 cm, and the spraying amount is 1~5 wt% of the weight gain of the dried substrate. S2: Select a prepreg according to the actual needs of the resin-based composite material component, and cut and lay up the prepreg in sequence to obtain a preform; S3: The substrate of the multifunctional film is laid on the surface of the preform, and then cured to obtain a low-power, high-durability anti-icing composite material.
2. The molding method as described in claim 1, characterized in that, In step S11, the soaking time is 12 to 36 hours.
3. The molding method as described in claim 1, characterized in that, In step S12, the epoxy resin is at least one of bisphenol A type, bisphenol F type, polyphenol type, and aliphatic type epoxy resin.
4. The molding method as described in claim 1, characterized in that, In step S13, the mass ratio of the modified epoxy resin to the curing agent is determined based on the epoxy value of the epoxy resin and the type of curing agent.
5. The molding method as described in claim 1, characterized in that, In step S14, the drying process involves placing the item in a 60°C oven and keeping it at that temperature for 10-30 minutes. The curing process is determined based on the curing process of the selected epoxy resin.
6. The molding method as described in claim 1, characterized in that, In step S3, the molding and curing regime is determined based on the curing regime of the resin in the prepreg.
7. A low-power, high-durability anti-icing composite material, characterized in that, The composite material is prepared and shaped by the molding method according to any one of claims 1 to 6; the composite material has a layered structure and is composed of a multifunctional film and a preform; the multifunctional film is composed of a porous electrothermal film and a photothermal superhydrophobic coating; the substrate surface of the multifunctional film is laid on the surface of the preform.
8. An application of a low-power, high-durability anti-icing and de-icing composite material, characterized in that, The composite material prepared by the molding method according to any one of claims 1 to 6 or the composite material according to claim 7 is applied to aircraft skin and wind turbine blades in high-latitude regions.