Metal surface differentiated aerogel material and preparation method thereof

Abstract

The invention provides a metal surface differentiated aerogel film material and a preparation method thereof, and aims to prepare a differentiated controllable aerogel film on the surface of a complex metal device, and the method comprises the following steps: preparing a dispersion liquid I and a dispersion liquid II, carrying out dual-channel atomization spraying, and drying the surface of the metal device to form a film. The method is simple and easy to implement, the characteristics of the aerogel film in a micron-sized area can be flexibly changed by continuously or discontinuously adjusting jet flow forming conditions, the characteristics of structures, components and the like of all parts of the aerogel material are different, the differentiated aerogel film is formed on the surface of a complex metal device through conformal printing, and therefore the differentiated aerogel film can be obtained according to the using scene. The performance of the aerogel film on the surface of the metal device is intelligently designed and differentially adjusted, so that diversified functions are realized, and the application range of the aerogel material is expanded.

Description

Technical Field

[0001] The present invention relates to the technical field of aerogel materials, and in particular to a metal surface differentiated aerogel film material and a preparation method thereof. Background Art

[0002] Aerogel is a porous solid material formed by the assembly of nanostructures and a large amount of air. It has typical nanopore characteristics, such as low density, high porosity and high surface area, and has broad application prospects in many fields. At present, oxide inorganic aerogels have attracted great attention from academia and industry as excellent lightweight thermal insulation materials. Among them, the more common silica aerogels and their fiber-reinforced composites have been mass-produced at home and abroad. In practical applications, current commercial aerogel materials cannot match the widespread insulation requirements of micro or complex device surfaces. The specific requirements include: 1) the need to form a well-conformal aerogel film on the device surface; 2) based on the different performance requirements of various parts of the device for thermal conductivity, hydrophobicity, etc., to form functionally differentiated aerogels in each tiny area.

[0003] Among the known technologies, extrusion 3D printing technology has been applied to additive manufacturing of silica aerogels due to its good ink compatibility advantage. For example, [Nature, 2020, 584 (7821): 387-392] reported a method for preparing silica aerogels by 3D printing induced by ammonia vapor extrusion; [Small Methods, (2022): 2200045] reported a method for preparing multi-component silica-based ceramic aerogels by thermal curing extrusion 3D printing. However, these methods can only be used to prepare aerogel materials with uniform performance on a plane, and there is currently no method for forming differentiated aerogel films on surfaces with complex concave and convex surfaces.

[0004] The basic principle of aerosol printing technology is to atomize the printing ink to form an aerosol jet, and under the constraint of sheath gas, focus and spray it to the target position, which has the following advantages: First, the atomized droplets of the aerosol jet printer can allow a higher solid content (up to 70%), reducing the solvent that needs to be removed and the structural collapse caused by the corresponding solvent volatilization, which is of great help to the aerosol drying step; second, non-contact printing can print tracks on uneven steps and curved surfaces, and conformally print on 3D objects; third, the process performance is excellent, the aerosol printing technology is not easy to clog the nozzle, suitable for long-term work, and its equipment has a high degree of automation, which is conducive to industrial application; fourth, the printing accuracy can be as high as 10μm, and the resolution is high. Since the formation of aerosol has low requirements on the viscosity of the ink, the printing resolution can be adjusted by adjusting parameters such as the viscosity of the ink, the atomization method, the flow rate of the atomizing gas and the bound gas, and the aperture of the inkjet nozzle.

[0005] In view of the shortcomings of the existing technology, it is necessary to provide a new metal surface differentiated aerogel film material and a preparation method thereof. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a method for preparing differentiated aerogel materials on metal surfaces, so as to solve the problem that conventional methods in the prior art are difficult to form differentiated aerogel films on surfaces with complex concave and convex surfaces and can only be used to prepare aerogel materials with uniform performance on a plane.

[0007] In order to solve the above problems, the present invention provides a method for preparing a metal surface differentiated aerogel material, comprising the following steps:

[0008] S1: Prepare dispersion:

[0009] A dispersant, a stabilizer, a hydrophobic agent, a cross-linking agent and a hydrophobic aerogel powder are sequentially added to a solvent under stirring to form a dispersion liquid I;

[0010] The precursor is hydrolyzed in a mixed solvent of water, acid and ethanol to prepare dispersion II;

[0011] S2: The dispersion liquid I and the dispersion liquid II obtained in step S1 are connected in parallel to an aerosol spray device, and liquid atomization and airflow spraying are performed simultaneously to form a mixed jet to print the aerogel precursor on the surface of the metal device; during the process, the jet formation conditions are continuously or stepwise changed, the substrate heating temperature of the aerosol jet printer is set to 30°C-80°C, and the sample after printing is heated for 5-10 minutes to form the in-situ synthesized aerogel film, thereby completing the preparation of differentiated aerogel materials on the metal surface.

[0012] Compared with the prior art, the metal surface differentiated aerogel material in the present application has the following advantages: the preparation method in the present invention provides a new method for preparing a metal surface differentiated aerogel film, the aerosol printing has high focusing accuracy and large working distance, and can print conformal aerogel films on the surface of complex metal devices, meeting the needs of aerogel film forming on the surface of complex metal devices in actual production; the concentrated atomization spray ratio in the printing process can be changed continuously or in stages, forming density, structure, composition and other characteristic differences in the micro-region of the film, realizing the modulation of aerogel film characteristics and functional differentiation design in the micron-level region; because aerosol printing atomizes the printed dispersion to form colloid or semi-solidified droplets, coupling and adjusting the composition of the dispersion and the atomization spray ratio can significantly reduce the solvent content after film formation, which helps to achieve atmospheric pressure drying of aerogels and reduce the difficulty and cost of aerogel processing. Therefore, according to the usage scenario, the performance of aerogel films on the surface of metal devices can be intelligently designed and modulated for differentiation, realizing diversified functions and expanding the application range of aerogel materials.

[0013] In a possible embodiment, in step S1, the dispersant is a cationic dispersant or an amphoteric dispersant, and the cationic dispersant includes amine salts, quaternary ammonium salts, and pyridinium salts, and the amphoteric dispersant is a phosphate salt; the stabilizer is selected from one of hydrochloric acid, phosphoric acid, ammonia water, and sodium hydroxide; the hydrophobic agent is selected from one of hexamethyldisilazane, propyltrimethoxysilane, and polytetrafluoroethylene; the cross-linking agent is selected from acetyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane; the hydrophobic aerogel powder is selected from nano-scale silicon oxide, titanium oxide, aluminum oxide aerogel powder or a mixture thereof.

[0014] In a possible embodiment, in the step S1, in the dispersion I used, the mass proportion of the dispersant is 0.05-2%, the mass proportion of the stabilizer is 0.05-5%, the mass proportion of the hydrophobic agent is 0.05-5%, the mass proportion of the cross-linking agent is 0.05-3%, and the mass proportion of the hydrophobic aerogel powder is 2-50%.

[0015] In a possible implementation, in the dispersion II used, the mass ratio of the precursor, the acid solution, and the ethanol is 1:(2-30):(2-30); and the pH value of the solvent mixed with water, acid, and ethanol is 4-6.

[0016] In a possible implementation, in step S1, the viscosity of the dispersion I and the dispersion II is 2-30 CPS, the surface tension is 5-50 mN / m, and the particle size of the dispersed particles is less than 1 um.

[0017] In a possible embodiment, in step S2, the aerosol spray device is an aerosol jet printer, and the liquid atomization operation includes: placing the dispersion I and dispersion II obtained in step S1 into atomizing bottle I and atomizing bottle II respectively, and connecting the atomizing bottle I and atomizing bottle II in parallel to the print nozzle of the aerosol jet printer, and starting the atomizing bottle I and atomizing bottle II at the same time, so that the atomized liquids in the atomizing bottle I and the atomizing bottle II enter the atomization channel of the aerosol jet printer at the same time.

[0018] In a possible embodiment, the atomization method used is ultrasonic atomization or pneumatic atomization, and the transport air flow rate of the atomized liquid is 50-10000sccm; the transport air flow rate ratio of the atomization bottle I and the atomization bottle II is (50-1): (1-50); the sheath gas speed is 500-10000sccm, and the speed ratio of the sheath gas to the atomizing gas flow is (100:1)-(1:1).

[0019] In a possible implementation, the diameter of the atomization channel outlet of the aerosol jet printer is 10-50um, the distance from the substrate is 1.5-5mm, and the angle between the outlet and the horizontal plane is set to 45-90°; the printing speed of the aerosol jet printer is 1-100mm / s.

[0020] In a possible implementation, the length, width and height of the metal device are limited to 200X200X100mm, and the surface step angle can be a right angle or an obtuse angle.

[0021] Another technical problem to be solved by the present invention is to provide a metal surface differentiated aerogel material to solve the problem that conventional aerogel materials in the prior art cannot form differentiated aerogel films on complex concave and convex surfaces, and to provide a metal surface differentiated aerogel material.

[0022] In order to solve the above technical problems, the present invention provides a metal surface differentiated aerogel material, and the metal surface differentiated aerogel material is prepared by the above preparation method.

[0023] A metal surface differentiated aerogel material in the present invention solves the problem that it is difficult to conformally print on the surface of conventional complex metal devices to form differentiated aerogel film aerogel materials. The aerogel material in the present invention can be intelligently designed and manufactured according to usage requirements to meet diversified functional needs and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the framework of the aerosol printing preparation method of the differentiated aerogel film material of the present invention;

[0025] Figure 2 is the difference in hydrophobicity of the differentiated aerogel on the device surface in Example 2 of the present invention, Figure 2 (a) is the contact angle of the film formed at the initial stage of printing, Figure 2 (b) is the contact angle of the film formed in the later stage of printing;

[0026] Figure 3 This is the effect of printing the differentiated aerogel on the stepped surface of the metal device in Example 2 of the present invention. Figure 3 (a) is a side view. Figure 3 (b) is a step angle cross-sectional view;

[0027] Figure 4 This is a diagram showing the effect of printing differentiated aerogel on the surface of a metal device in Example 3 of the present invention. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below. It should be noted that the following embodiments are only used to illustrate the implementation method and typical parameters of the present invention, and are not used to limit the parameter range described in the present invention. Reasonable changes derived therefrom are still within the scope of protection of the claims of the present invention.

[0029] It should be noted that the endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this article.

[0030] like Figure 1 As shown, Figure 1 The present invention provides a method for preparing a differentiated aerogel film material on a metal surface, comprising the following steps:

[0031] S1: Prepare dispersion:

[0032] A dispersant, a stabilizer, a hydrophobic agent, a cross-linking agent and a hydrophobic aerogel powder are sequentially added to a solvent by stirring to form a stable dispersion I;

[0033] The precursor is hydrolyzed in a mixed solvent of water, acid and ethanol to prepare dispersion II;

[0034] S2: The dispersion liquid I and the dispersion liquid II obtained in step S1 are connected in parallel to an aerosol spray device, and liquid atomization and airflow spraying are performed simultaneously to form a mixed jet to print the aerogel precursor on the surface of the metal device; during the process, the jet formation conditions are continuously or stepwise changed, the substrate heating temperature of the aerosol jet printer is set to 30°C-80°C, and the sample after printing is heated for 5-10 minutes to form the in-situ synthesized aerogel film, thereby completing the preparation of differentiated aerogel materials on the metal surface.

[0035] As a preferred scheme, in the step S1, the dispersant is a cationic dispersant or an amphoteric dispersant, and the cationic dispersant includes amine salts, quaternary ammonium salts, and pyridinium salts, and the amphoteric dispersant is a phosphate salt; the stabilizer is selected from one of hydrochloric acid, phosphoric acid, ammonia water, and sodium hydroxide; the hydrophobic agent is selected from one of hexamethyldisilazane, propyltrimethoxysilane, and polytetrafluoroethylene; the cross-linking agent is selected from acetyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane; the hydrophobic aerogel powder is selected from nano-scale silicon oxide, titanium oxide, aluminum oxide aerogel powder or a mixture thereof.

[0036] As a preferred solution, in step S1, in the dispersion I used, the mass proportion of the dispersant is 0.05-2%, the mass proportion of the stabilizer is 0.05-5%, the mass proportion of the hydrophobic agent is 0.05-5%, the mass proportion of the cross-linking agent is 0.05-3%, and the mass proportion of the hydrophobic aerogel powder is 2-50%.

[0037] As a preferred solution, in the dispersion II used, the mass ratio of the precursor, the acid solution and the ethanol is 1:(2-30):(2-30); the pH value of the solvent mixed with water, acid and ethanol is 4-6.

[0038] As a preferred solution, in step S1, the viscosity of the dispersion I and the dispersion II is 2-30 CPS, the surface tension is 5-50 mN / m, and the particle size of the dispersed particles is less than 1 um.

[0039] As a preferred solution, in step S2, the aerosol spray device is an aerosol jet printer, and the liquid atomization operation includes: placing the dispersion I and dispersion II obtained in step S1 into atomizing bottle I and atomizing bottle II respectively, and connecting the atomizing bottle I and atomizing bottle II in parallel to the print nozzle of the aerosol jet printer, and starting the atomizing bottle I and atomizing bottle II at the same time, so that the atomized liquids in the atomizing bottle I and atomizing bottle II enter the atomization channel of the aerosol jet printer at the same time.

[0040] As a preferred solution, the nebulizer bottle used is ultrasonic nebulizer or pneumatic nebulizer, and the transport air flow rate of the nebulized liquid is 50-10000sccm; the transport air flow rate ratio of the nebulizer bottle I and the nebulizer bottle II is (50-1): (1-50); the sheath gas speed is 500-10000sccm, and the speed ratio of the sheath gas to the nebulizer gas flow is (100:1)-(1:1).

[0041] As a preferred solution, the diameter of the atomization channel outlet of the aerosol jet printer is 10-50um, the distance from the substrate is 1.5-5mm, and the angle between the outlet and the horizontal plane is set to 45-90°; the printing speed of the aerosol jet printer is 1-100mm / s.

[0042] As a preferred solution, the length, width and height of the metal device are limited to 200X200X100mm, and the surface step angle can be a right angle or an obtuse angle.

[0043] The present invention also provides a metal surface differentiated aerogel material, and the metal surface differentiated aerogel material is prepared by the above-mentioned preparation method.

[0044] The present application is further described in detail below in conjunction with the accompanying drawings and specific examples. In the following examples, preparation methods involving different components and different mass ratios in specific steps and performance characterizations and pictures of products prepared by some preparation methods are provided, but the present invention is not limited to the scope of the following examples, and the scope in the above technical scheme should be included in the protection scope of the present invention; in addition, the difference in hydrophobicity in the embodiments of the present invention is characterized by a water contact angle test.

[0045] Example 1

[0046] Example 1 provides a metal surface differentiated aerogel material and a preparation method thereof, wherein the metal surface differentiated aerogel material is prepared by the following preparation method:

[0047] S1: 5 g of water and 5 g of ethanol were mixed, and 0.1 g of Jeffamine M-2070 compound, 0.2 g of ammonia water, 0.3 g of polytetrafluoroethylene, and 0.05 g of acetyltrimethoxysilane were added to the water-alcohol solution. 5 g of hydrophobic silica aerogel powder was added to the solvent in batches under rapid stirring to form a stable dispersion I;

[0048] Mix 5g of water and 5g of ethanol, add 1g of ethyl orthosilicate into the solvent, add sulfuric acid dropwise to adjust the pH of the mixture to 4.5, heat in a water bath at 50°C for 1h, and hydrolyze to obtain dispersion II;

[0049] S2: Dispersion I and dispersion II are placed in ultrasonic atomization bottle I and ultrasonic atomization bottle II respectively, and atomization bottle I and atomization bottle II are connected in parallel to the print nozzle of the aerosol jet printer. The atomization bottle transport gas flow is set to 1000sccm, and the sheath gas flow is set to 10000sccm. Atomization bottle I and atomization bottle II are started at the same time, so that the atomized liquids in atomization bottle I and atomization bottle II enter the atomization channel of the aerosol jet printer at the same time; the distance between the nozzle and the surface of the metal device is set to 1mm, and the nozzle is perpendicular to the horizontal plane; take a 5X5X1cm metal device and place it on the substrate, set the substrate heating temperature of the aerosol jet printer to 50℃, and heat the sample after printing for 10min to make the in-situ synthesized aerogel film quickly form.

[0050] like Figure 2 As shown, the effect of differential aerogel printing on the stepped surface of metal devices was observed by SEM electron microscopy. Figure 2 (a) is a side view. Figure 2 (b) is a step angle cross-sectional view, Figure 2 It is illustrated that the aerogel film prepared by the preparation method of the present invention has good adhesion to the device surface.

[0051] Example 2

[0052] Example 2 provides a metal surface differentiated aerogel material and a preparation method thereof, wherein the metal surface differentiated aerogel material is prepared by the following preparation method:

[0053] S1: 7 g of water and 3 g of ethanol were mixed, and 0.05 g of Surfonamine B-200 compound, 0.2 g of ammonia water, 0.3 g of hexamethyldisilazane, and 0.05 g of γ-aminopropyltriethoxysilane were added to the aqueous alcohol solution, and 4 g of hydrophobic silica aerogel powder was added to the solvent in batches under rapid stirring to form a stable dispersion I;

[0054] Take 5g of water and 5g of ethanol, mix them, add 1g of ethyl orthosilicate into the solvent, drop sulfuric acid into the mixture to adjust the pH value to 6, heat in a water bath at 70℃ for 2h, and hydrolyze to obtain dispersion II;

[0055] S2: Dispersion I and dispersion II are placed in ultrasonic atomization bottle I and ultrasonic atomization bottle II respectively, and atomization bottle I and atomization bottle II are connected in parallel to the print head of the aerosol jet printer, the transport gas flow is set to 500sccm, the sheath gas flow is set to 1000sccm, and atomization bottle I and atomization bottle II are started at the same time, so that the atomized liquids in atomization bottle I and atomization bottle II enter the atomization channel of the aerosol jet printer at the same time. At the same time, during the spraying process, the air flow transport speed of atomization bottle II is increased at a speed of 10sccm / min; the distance between the nozzle and the surface of the metal device is set to 3mm, and the angle between the nozzle and the horizontal plane is 45°; take a 5X5X1cm metal device and place it on the substrate, set the substrate heating temperature of the aerosol jet printer to 80℃, and heat the sample after printing for 5min to allow the in-situ synthesized aerogel film to form quickly.

[0056] The hydrophobicity of the differentiated aerogel on the device surface in this embodiment was tested by the contact angle of water. Figure 3 As shown, the center distance between the adjacent A and B regions of the aerogel film is about 1 mm, and A is formed before B. Figure 3 (a) is the contact angle of region A, Figure 3 (b) is the contact angle of the film formed in region B, and there is an obvious difference in hydrophobicity; this indicates that the present invention can be used to prepare aerogel films with different properties in tiny regions.

[0057] Example 3

[0058] Example 3 provides a metal surface differentiated aerogel material and a preparation method thereof. The metal surface differentiated aerogel material is prepared by the following preparation method:

[0059] S1: 8 g of water was mixed with 2 g of ethanol, and 0.05 g of Jeffamine M600 compound, 0.05 g of sodium hydroxide, 0.1 g of hexamethyldisilazane, and 0.05 g of γ-mercaptopropyltriethoxy were added to the water-alcohol solution, and 6 g of hydrophobic silica aerogel powder was added to the solvent in batches under rapid stirring to form a stable dispersion I;

[0060] Mix 6g of water and 4g of ethanol, add 2g of tetraethyl orthosilicate into the solvent, add nitric acid dropwise to adjust the pH of the mixture to 5.5, heat in a water bath at 40°C for 1h, and hydrolyze to obtain dispersion II;

[0061] S2: Dispersion I and dispersion II are placed in ultrasonic atomization bottle I and ultrasonic atomization bottle II respectively, and atomization bottle I and atomization bottle II are connected in parallel to the print head of the aerosol jet printer, the transport gas flow is set to 1500sccm, the sheath gas flow is set to 10000sccm, and atomization bottle I and atomization bottle II are started so that the atomized liquids in atomization bottle I and atomization bottle II enter the atomization channel of the aerosol jet printer at the same time. At the same time, during the spraying process, the sheath gas transport speed is reduced at a speed gradient of 30sccm / min; the distance between the nozzle and the surface of the metal device is set to 3mm, and the angle between the nozzle and the horizontal plane is 45°; a 10X10X1cm metal device with a concave and convex surface is taken and placed on the substrate, the substrate heating temperature of the aerosol jet printer is set to 80°C, and the sample after printing is heated for 5min to allow the in-situ synthesized aerogel film to form quickly.

[0062] like Figure 4 As shown, the effect of printing the differentiated aerogel on the surface of the metal device in this embodiment was observed by SEM electron microscopy. The order of film formation is (a)(b)(c). It can be seen that as the sheath gas flow decreases, the thickness of the aerogel film decreases continuously, achieving a corresponding continuous decrease in the thermal resistance of the metal surface.

[0063] Example 4

[0064] Example 4 provides a metal surface differentiated aerogel material and a preparation method thereof. The metal surface differentiated aerogel material is prepared by the following preparation method:

[0065] S1: 8 g of water and 2 g of isopropanol were mixed, and 0.05 g of Petrolite D1038 compound, 0.05 g of hydrochloric acid, 0.1 g of polytetrafluoroethylene, and 0.05 g of propyltrimethoxysilane were added to the water-alcohol solution. 3 g of hydrophobic alumina and 3 g of hydrophobic silica aerogel powder were added to the solvent in batches under rapid stirring to form a stable dispersion I;

[0066] Mix 4 g of water with 6 g of ethanol, add 2 g of aluminum isopropoxide to the solvent, add nitric acid dropwise to adjust the pH of the mixture to 4, heat in a water bath at 45°C for 12 h, and hydrolyze to obtain dispersion II;

[0067] S2: Dispersion I and dispersion II are placed in ultrasonic atomization bottle I and pneumatic atomization bottle II, respectively, and atomization bottle I and atomization bottle II are connected in parallel to the print head of the aerosol jet printer, the transport air flow of atomization bottle I is set to 500 sccm, the transport air flow of atomization bottle II is set to 5000 sccm, the sheath gas flow is set to 10000 sccm, and atomization bottle I and atomization bottle II are started at the same time, so that the atomized liquids in atomization bottle I and atomization bottle II enter the atomization channel of the aerosol jet printer at the same time, and at the same time in the spray nozzle. During the coating process, the air flow transport speed of the atomizer bottle II is cycled between 5000-2500-5000-7500sccm, and each speed is maintained for 1 min; the distance between the nozzle and the surface of the metal device is set to 5 mm, and the angle between the nozzle and the horizontal plane is 60°; a 10X10X1cm metal device with a concave and convex surface is placed on the substrate, the substrate heating temperature of the aerosol jet printer is set to 70°C, and the printed sample is heated for 7 minutes to allow the in-situ synthesized aerogel film to form quickly.

[0068] Example 5

[0069] Example 5 provides a metal surface differentiated aerogel material and a preparation method thereof. The metal surface differentiated aerogel material is prepared by the following preparation method:

[0070] S1: 4 g of water and 6 g of isopropanol were mixed, and 0.05 g of phosphate compound, 0.01 g of hydrochloric acid, 0.1 g of propyltrimethoxysilane, and 0.05 g of γ-(methacryloyloxy)propyltrimethoxysilane were added to the water-alcohol solution, and 1 g of hydrophobic titanium oxide aerogel powder was added to the solvent in batches under rapid stirring to form a stable dispersion I;

[0071] Mix 4 g of water with 6 g of ethanol, add 1.5 g of tetrabutyl titanate into the solvent, add phosphoric acid dropwise to adjust the pH of the mixture to 4.5, heat in a water bath at 35°C for 15 h, and hydrolyze to obtain dispersion II;

[0072] S2: Dispersion liquid I and dispersion liquid II are placed in ultrasonic atomization bottle I and pneumatic atomization bottle II, respectively, and atomization bottle I and atomization bottle II are connected in parallel to the print head of the aerosol jet printer, the transport air flow of atomization bottle I is set to 100 sccm, the transport air flow of atomization bottle II is set to 500 sccm, the sheath gas flow is set to 1000 sccm, atomization bottle II is kept heated, and atomization bottle I and atomization bottle II are started at the same time, so that the atomized liquids in atomization bottle I and atomization bottle II enter the aerosol jet printer at the same time. In the atomization channel of the printer, during the spraying process, the heating temperature of the atomization bottle II is gradually increased from 30°C to 50°C, with a gradient of 5°C / section, and each temperature is maintained for 1 min; the distance between the nozzle and the surface of the metal device is set to 4 mm, and the angle between the nozzle and the horizontal plane is 45°; a metal dish with a diameter of 5 and a height of 0.5 cm is placed on the substrate, the substrate heating temperature of the aerosol jet printer is set to 70°C, and the printed sample is heated for 7 minutes to allow the in-situ synthesized aerogel film to form quickly.

[0073] Further explanation of the above embodiments also proves that the present invention provides a differentiated aerogel film material on a metal surface and a preparation method thereof. The preparation method of the present invention can flexibly change the aerogel film properties in the micrometer-level region by adjusting the atomization injection ratio of the dispersion liquid, so that the structure, composition and other properties of each part of the aerogel material are different, and a differentiated aerogel film is formed by conformal printing on the surface of a complex metal device. Therefore, according to the usage scenario, the performance of the aerogel film on the surface of the metal device can be intelligently designed and modulated for differential processing, thereby realizing diversified functions and expanding the application range of aerogel materials.

[0074] In the description of the embodiments of the present application, it should be noted that in the description of the present application, terms such as "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description, and does not indicate or imply that the device or component must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present application.

[0075] In the description of the present application, the description with reference to the terms "one embodiment", "some embodiments", "in the present embodiment", "specific example", or "some examples" etc. means that the specific features, mechanisms, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0076] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for preparing a metal surface differentiated aerogel material, characterized in that: The following steps are involved: S1: Prepare dispersion: A dispersant, a stabilizer, a hydrophobic agent, a cross-linking agent and a hydrophobic aerogel powder are sequentially added to a solvent under stirring to form a dispersion liquid I; The precursor is hydrolyzed in a mixed solvent of water, acid and ethanol to prepare dispersion II; S2: The dispersion liquid I and the dispersion liquid II obtained in step S1 are connected in parallel to an aerosol spray device, and liquid atomization and airflow spraying are performed simultaneously to form a mixed jet to print the aerogel precursor on the surface of the metal device; during the process, the jet formation conditions are continuously or stepwise changed, the substrate heating temperature of the aerosol jet printer is set to 30°C-80°C, and the sample after printing is heated for 5-10 minutes to form the in-situ synthesized aerogel film, thereby completing the preparation of differentiated aerogel materials on the metal surface.

2. The method for preparing a metal surface differentiated aerogel material according to claim 1, characterized in that: In the step S1, the dispersant is a cationic dispersant or an amphoteric dispersant, and the cationic dispersant includes amine salts, quaternary ammonium salts, and pyridinium salts, and the amphoteric dispersant is a phosphate salt; the stabilizer is selected from one of hydrochloric acid, phosphoric acid, ammonia water, and sodium hydroxide; the hydrophobic agent is selected from one of hexamethyldisilazane, propyltrimethoxysilane, and polytetrafluoroethylene; the cross-linking agent is selected from acetyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane; the hydrophobic aerogel powder is selected from nano-scale silicon oxide, titanium oxide, aluminum oxide aerogel powder or a mixture thereof.

3. The method for preparing a metal surface differentiated aerogel material according to claim 1, characterized in that: In the step S1, in the dispersion I used, the mass proportion of the dispersant is 0.05-2%, the mass proportion of the stabilizer is 0.05-5%, the mass proportion of the hydrophobic agent is 0.05-5%, the mass proportion of the cross-linking agent is 0.05-3%, and the mass proportion of the hydrophobic aerogel powder is 2-50%.

4. The method for preparing a metal surface differentiated aerogel material according to claim 1, characterized in that: In the step S1, in the dispersion II used, the mass ratio of the precursor, the acid solution and the ethanol is 1:(2-30):(2-30); the pH value of the solvent mixed with water, acid and ethanol is 4-6.

5. The method for preparing a metal surface differentiated aerogel material according to claim 1, characterized in that: In the step S1, the viscosity of the dispersion liquid I and the dispersion liquid II is 2-30 CPS.

6. The method for preparing aerogel material with metal surface differentiation according to claim 1, characterized in that: In the step S2, the aerosol spray device is an aerosol jet printer, and the liquid atomization operation includes: putting the dispersion liquid I and the dispersion liquid II obtained in the step S1 into the atomizing bottle I and the atomizing bottle II respectively, and connecting the atomizing bottle I and the atomizing bottle II in parallel to the print nozzle of the aerosol jet printer, and starting the atomizing bottle I and the atomizing bottle II at the same time, so that the atomized liquids in the atomizing bottle I and the atomizing bottle II enter the atomizing channel of the aerosol jet printer at the same time.

7. The method for preparing a metal surface differentiated aerogel material according to claim 6, characterized in that: The atomizing bottle used is ultrasonic atomization or pneumatic atomization, and the transport air flow rate of the atomized liquid is 50-10000sccm; the transport air flow rate ratio of the atomizing bottle I and the atomizing bottle II is (50-1): (1-50).

8. The method for preparing a metal surface differentiated aerogel material according to claim 6, characterized in that: The diameter of the atomization channel outlet of the aerosol jet printer is 10-50um, the distance from the substrate is 1.5-5mm, and the angle between the outlet and the horizontal plane is set to 45-90°; the printing speed of the aerosol jet printer is 1-100mm / s.

9. A metal surface differentiated aerogel material, characterized in that: The metal surface differentiated aerogel material is prepared by any one of the preparation methods of claims 1-8.

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