Dual-response type intelligent micro-capsule, anti-icing insulator coating and preparation process of anti-icing insulator coating

Abstract

The invention discloses a dual response type intelligent micro-capsule, an anti-icing insulator coating and a preparation process of the anti-icing insulator coating. The micro-capsule adopts a PDMAEMA / ZIF-8 hybrid composite material as a capsule wall, and hydrophobic small molecules and a repairing agent are encapsulated in the micro-capsule. The capsule wall has hierarchical response characteristics: hydrophobic molecules are slowly released daily to maintain super-hydrophobicity; the early warning protection effect is achieved through accelerated release in a weak acid environment; and when strong acid or mechanical damage occurs, the repair agent is broken and released to realize rapid self-healing repair. The microcapsule is used as a functional filler to be compounded with matrixes such as epoxy modified organic silicon resin and the like, and is coated on the surface of an insulator by adopting a spraying and stepped curing process. The problems that the hydrophobic performance of a traditional coating is irreversibly attenuated and the repairing mechanism is single are effectively solved, integrated cooperation of long-acting dynamic maintenance, environment early warning and active repairing is achieved, the anti-icing capacity of an insulator in a severe environment is remarkably improved, and the service life of the insulator in the severe environment is remarkably prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of anti-icing insulator coating preparation, in particular to a double-response type intelligent microcapsule, an anti-icing insulator coating and a preparation process thereof. BACKGROUND

[0002] Insulators are key external insulation equipment of power transmission networks, and their operation reliability is crucial to the safety of the power grid. In cold and humid environments, icing is prone to occur on the surface of insulators, which not only shortens the effective insulation distance and induces ice flashover accidents, but also causes mechanical structure damage due to uneven icing or ice shedding, which seriously threatens the stability of the power grid.

[0003] To address the above problems, super-hydrophobic anti-icing coating technology has been widely studied as an effective passive protection strategy. This type of coating creates a micro-nano rough structure and modifies low surface energy materials to make the surface super-hydrophobic, which can significantly delay icing and reduce ice adhesion, thereby achieving anti-icing and easy deicing effects. However, existing technologies still have obvious limitations in practical applications, which restrict their large-scale promotion:

[0004] Lack of durability, irreversible performance degradation: The function of traditional super-hydrophobic coatings is highly dependent on the surface microstructure and chemical composition. In long-term outdoor exposure, environmental stresses such as ultraviolet radiation, rain and snow erosion, wind and sand abrasion, and acid rain erosion can irreversibly damage the surface structure and deplete low surface energy materials, leading to rapid decline in hydrophobicity and difficulty in maintaining anti-icing effect.

[0005] Single self-repair mechanism, passive: Although some studies have introduced self-repairing microcapsules to repair physical damage, most existing microcapsules only respond to a single stimulus, mechanical cracks, which is a passive repair mechanism. This mechanism cannot solve the problem of slow increase in surface energy caused by routine aging, and does not have the ability to provide early warning and active protection against specific environmental threats, such as the formation of acidic water film indicating icing risk.

[0006] Poor functional synergy, low system integration: Most solutions simply stack hydrophobic and repair functions without effective synergy between functions. Common cases are that the repair process cannot restore the super-hydrophobicity of the region synchronously, or the introduction of repair components sacrifices the original mechanical properties and hydrophobic effect of the coating.

[0007] Therefore, the present application proposes an anti-icing insulator coating based on a double-response type intelligent microcapsule. This coating not only has excellent initial super-hydrophobic and anti-icing properties, but also realizes graded response to routine aging, environmental changes and mechanical damage, enabling full-cycle active protection from dynamic maintenance, early warning and protection to damage repair, thereby significantly improving long-term service reliability in harsh environments. SUMMARY

[0008] To solve the above technical problems, the present application provides a dual-responsive intelligent microcapsule, an anti-icing insulator coating and a preparation process thereof. In the technical solution of the present application, the dual-responsive intelligent microcapsule has a core-shell structure, comprising:

[0009] The inner core contains a hydrophobic small molecule and a repair agent.

[0010] The capsule wall is composed of poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) and zeolitic imidazolate framework material (ZIF-8) nanoparticles.

[0011] Under normal conditions, the capsule wall allows the hydrophobic small molecule to be released at a first rate.

[0012] In a weak acidic environment, the poly(N,N-dimethylaminoethyl methacrylate) is protonated and swells, allowing the hydrophobic small molecule to be released at a second rate higher than the first rate.

[0013] In a strong acidic environment or mechanical damage, the capsule wall is broken, releasing the repair agent.

[0014] Further, in the technical solution of the present application, the hydrophobic small molecule is at least one of perfluorooctyltriethoxysilane or hexadecyltrimethoxysilane.

[0015] Further, in the technical solution of the present application, the repair agent is at least one of dicyclopentadiene or hydroxyl-terminated polydimethylsiloxane.

[0016] Further, in the technical solution of the present application, in the inner core, the weight ratio of the hydrophobic small molecule to the repair agent is 60-70:30-40.

[0017] Further, in the technical solution of the present application, the capsule wall material includes, by weight:

[0018] Poly(N,N-dimethylaminoethyl methacrylate) 100 parts;

[0019] Zeolitic imidazolate framework material nanoparticles 10-20 parts;

[0020] Crosslinking agent 5-10 parts.

[0021] An anti-icing insulator coating contains the above-mentioned dual-responsive intelligent microcapsule, and the coating raw material includes, by mass fraction:

[0022] Epoxy-modified silicone resin 100 parts;

[0023] Dual-responsive intelligent microcapsule 5-15 parts;

[0024] Silane coupling agent 3-5 parts;

[0025] Solvent 40-60 parts.

[0026] Further, in the technical scheme of the present application, the epoxy-modified silicone resin is pre-dispersed with a catalyst for triggering the polymerization of the repair agent.

[0027] A preparation process of an anti-icing insulator coating, comprising the following steps:

[0028] ① A double-response intelligent microcapsule is prepared by using a multiple emulsion-solvent evaporation method;

[0029] ② The epoxy-modified silicone resin and the catalyst are mixed in proportion to obtain a pretreated matrix resin;

[0030] ③ The intelligent microcapsule prepared in step ①, the pretreated matrix resin prepared in step ②, a silane coupling agent and a solvent are mixed and uniformly dispersed to form a coating slurry;

[0031] ④ The coating slurry is coated on the surface of the insulator substrate, and a solidification treatment is performed to form an anti-icing insulator coating;

[0032] Wherein, the coating is performed by using an air spraying method, the spraying pressure is 0.3-0.5 MPa, and the spraying distance is 20-30 cm; the solidification treatment is specifically a stepwise temperature rising solidification: first solidification at 60℃ for 1 hour, and then solidification at 80℃ for 2 hours.

[0033] Further, in the technical scheme of the present application, the multiple emulsion-solvent evaporation method in step ① specifically comprises the following steps:

[0034] ① A hydrophobic small molecule and a repair agent are mixed in proportion as an inner water phase;

[0035] ② Poly (N,N-dimethylaminoethyl methacrylate) and zeolite imidazolate framework material nanoparticles are dissolved or dispersed in dichloromethane in proportion to form an oil phase;

[0036] ③ The oil phase of step ② and the inner water phase of step ① are mixed and high-speed sheared to form a primary emulsion;

[0037] ④ The primary emulsion is added to an outer water phase containing a stabilizer polyvinyl alcohol, and medium-speed stirring emulsification is performed to form a multiple emulsion;

[0038] ⑤ The solvent is volatilized under continuous stirring, the capsule wall material is crosslinked and solidified at the oil-water interface, and post-treatment is performed to obtain a double-response intelligent microcapsule powder;

[0039] Specifically, the stirring rate is 300-500 rpm, the crosslinking and solidification temperature is 40±2℃, and the solidification time is 6-8h.

[0040] Further, in the technical scheme of the present application, the post-treatment in step 5 includes: centrifugation at 3000-4000 rpm for 10-15 min, collection of the solid phase, washing with 4℃ pre-cooled deionized water for 3 times, subsequent pre-freezing to-80℃, and then freeze-drying at-50℃ under a vacuum of less than 10 Pa for 24-36 h.

[0041] Effective gain:

[0042] In the technical scheme of the present application, through the unique design of the PDMAEMA / ZIF-8 organic-inorganic hybrid capsule wall, the hydrophobic small molecules are continuously, controllably and slowly released on a daily basis, the low-surface-energy substances on the surface of the coating can be dynamically supplemented, the metabolism of the super-hydrophobic performance is realized, and the effective protection life of the coating is prolonged. When in a micro-acidic condition caused by ice melting or dirt adhesion, the PDMAEMA proton swells, the porosity increases, the release of the hydrophobic small molecules is accelerated, and the hydrophobic protection performance is improved. When in a strong acid environment or a micro-crack occurs, the microcapsules are broken, the hydrophobic small molecules and the repair agent are released at the same time, the repair and the recovery of the hydrophobicity are realized, the three-level response from daily maintenance to environmental warning to damage repair is realized, the precision and reliability of the protection are improved, and the misuse and waste of repair resources are avoided.

[0043] Meanwhile, the repair agent and the hydrophobic small molecules are co-encapsulated in the same microcapsule core, the release behaviors of the two are accurately controlled by the capsule wall, the repair function and the hydrophobic function are closely coordinated in time and space. This not only simplifies the coating formula, but also ensures that the super-hydrophobicity of the region can be recovered at the same time when the physical crack is repaired, realizes the integrated effect of “repairing and recovering”, and doubles the comprehensive protection efficiency.

[0044] Other features and advantages of the present application will be described in the following description. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings described in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating laborious work on the basis of these drawings.

[0046] Figure 1 A preparation flow chart of the anti-icing insulator coating of the present application.

[0047] Figure 2 A contact angle change broken line graph of the anti-icing insulator coating of the present application in different pH environments. DETAILED DESCRIPTION

[0048] In order to make the objectives, characteristics and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the embodiments described below are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0049] The present application provides a dual-responsive intelligent microcapsule with a core-shell structure, wherein the core comprises a hydrophobic small molecule and a repairing agent. The capsule wall material comprises, by weight fraction:

[0050] 100 parts of PDMAEMA;

[0051] 10-20 parts of ZIF-8 nanoparticles;

[0052] 5-10 parts of a crosslinking agent.

[0053] The PDMAEMA has a molecular weight of 50,000-100,000 Da. If the molecular weight is too low, the film-forming property and mechanical strength are insufficient. If the molecular weight is too high, the viscosity is too large and the dispersity is <1.5. The ZIF-8 nanoparticles have a particle size of 50-100 nm and a specific surface area of ≥1000 m 2 / g.

[0054] In the present embodiment, the PDMAEMA is selected from Shanghai Maikelin Biochemical Technology Co., Ltd. and has a model number of Poly(2-(dimethylamino)ethyl methacrylate)-723067. The ZIF-8 nanoparticles are selected from Nanjing Xianfeng Nanometer Material Technology Co., Ltd. and have a model number of ZIF-8.

[0055] Specifically, the hydrophobic small molecule is at least one of perfluorooctyltriethoxysilane or hexadecyltrimethoxysilane. The repairing agent is at least one of dicyclopentadiene or a hydroxyl-terminated polydimethylsiloxane. The weight fraction ratio of the hydrophobic small molecule to the repairing agent is 60-70:30-40.

[0056] In the present embodiment, the capsule wall is formed by hybridizing and compounding the PDMAEMA and the ZIF-8 nanoparticles. Under daily conditions, the micropores in the capsule wall allow the hydrophobic small molecule to be released slowly at a first rate;

[0057] In a weakly acidic environment caused by ice melting or pollutant adhesion, the PDMAEMA is protonated and swells, the void fraction increases, and the hydrophobic small molecule is released at a second rate higher than the first rate.

[0058] In the strong acid environment, ZIF-8 nanoparticles are dissolved, microcapsules are disintegrated, or mechanically damaged, and the capsule wall is broken, releasing the hydrophobic small molecules and the repair agent in the core to repair and supplement hydrophobicity.

[0059] Another aspect of the present application provides an anti-icing insulator coating, and the raw materials of the coating include, by mass fraction:

[0060] Epoxy-modified silicone resin 100 parts;

[0061] Dual-responsive intelligent microcapsules 5-15 parts;

[0062] Fluorosilane coupling agent 3-5 parts;

[0063] Solvent 40-60 parts.

[0064] Among them, the epoxy-modified silicone resin combines the strong adhesion of epoxy and the flexibility of silicone, serving as the coating matrix to provide adhesion and weather resistance. In this embodiment, the epoxy-modified silicone resin is selected from the DOW CORNING® 8040 series.

[0065] The silane coupling agent cooperates with the microcapsules to reduce the surface energy and improve the bonding force between the microcapsules and the matrix. In this embodiment, the silane coupling agent is any one of KH-550, KH-560, and KH-570. In other embodiments, the preferred silane coupling agent is a fluorosilane coupling agent, specifically any one of FAS-17, FAS-13, FAS-19, and KF-63. The fluorosilane coupling agent further improves the hydrophobicity of the coating based on improving the bonding force of the microcapsules.

[0066] The solvent is ethyl acetate or propylene glycol methyl ether acetate, and the mixture solid content is controlled at 30%-40%. The spraying viscosity is adjusted by controlling the amount of solvent.

[0067] Further, a catalyst for triggering the polymerization of the repair agent is pre-dispersed in the epoxy-modified silicone resin. The catalyst is a ROMP catalyst, and its content is 0.5-1.5 wt% of the epoxy-modified silicone resin, which is used to trigger the polymerization of the repair agent to repair cracks. In this embodiment, the catalyst is selected from Sigma-Aldrich, and the model is Grubbs second-generation catalyst.

[0068] The present application also provides a preparation process for an anti-icing insulator coating, including the following steps:

[0069] ① Dual-responsive intelligent microcapsules are prepared by the multiple emulsion-solvent evaporation method;

[0070] The hydrophobic small molecules and the repair agent are mixed in proportion to serve as the core aqueous phase;

[0071] 40 kHz ultrasonic treatment of ZIF-8 and dichloromethane mixture for 30 minutes, then add PDMAEMA solution to continue to disperse and dissolve, forming an oil phase;

[0072] Mix the above oil phase with the inner core water phase, and emulsify at a high speed of 10000-12000 rpm for 5-8 min to form a primary emulsion;

[0073] Add the primary emulsion to the outer water phase containing polyvinyl alcohol, and emulsify at a medium speed of 500-600 rpm for 20-30 min to form a multiple emulsion;

[0074] Continue stirring at 300-500 rpm to promote solvent evaporation, and the capsule wall material is crosslinked and solidified at the oil-water interface, with a crosslinking and solidification temperature of 40±2℃ and a solidification time of 6-8 h. After post-processing, a double-response intelligent microcapsule powder is obtained;

[0075] It can be understood that by controlling the crosslinking and solidification temperature to control the evaporation rate of dichloromethane, when the temperature is <35℃, the evaporation is too slow, resulting in loose capsule wall structure and decreased encapsulation efficiency; when the temperature is >45℃, the evaporation is too fast, which is easy to form bubbles or defects in the capsule wall, and the internal pressure increases rapidly, causing the microcapsule to deform or rupture. In this embodiment, the preferred crosslinking and solidification temperature is 40℃.

[0076] Specifically, the post-processing includes: centrifugation at a speed of 3000-4000 rpm for 10-15 min, collection of the solid phase, washing with 4℃ pre-cooled deionized water for 3 times, followed by pre-freezing to-80℃, and then freeze-drying at-50℃ under a vacuum of less than 10 Pa for 24-36 h.

[0077] It should be noted that the water phase impurities attached to the surface of the microcapsule are removed by washing with deionized water, and the pre-cooled water rapidly reduces the temperature of the system, sharply reducing the movement ability of the polymer chain segments, so as to lock the microstructure of the capsule wall in a more compact and stable state.

[0078] ②Mix the epoxy-modified silicone resin with the catalyst in proportion to obtain a pretreated matrix resin;

[0079] ③Mix the intelligent microcapsule prepared in step ①, the pretreated matrix resin prepared in step ②, the silane coupling agent, and the solvent to form a coating slurry, which is uniformly dispersed at 2000 rpm for 30 min;

[0080] ④Apply the coating slurry to the surface of the insulator substrate, and perform curing treatment to form an anti-icing insulator coating;

[0081] The coating is performed by air spraying, the spraying pressure is 0.3-0.5 MPa, and the spraying distance is 20-30 cm; the solidification treatment is specifically stepwise temperature solidification, first solidification at 60℃ for 1 hour, then solidification at 80℃ for 2 hours, and finally room temperature curing for 24 hours.

[0082] In the embodiment, sand blasting is performed on the surface of the insulator before coating, the sand blasting is specifically Al2O3 sand with a particle size of 0.5 mm, and then ultrasonic cleaning and plasma treatment are performed to activate the surface of the insulator.

[0083] In order to further understand the present application, the anti-icing insulator coating provided by the present application is described below in combination with examples, and the protection scope of the present application is not limited by the following examples.

[0084] Example 1

[0085] Preparation of double-response intelligent microcapsules:

[0086] The perfluorooctyltriethoxysilane and dicyclopentadiene are mixed at a weight ratio of 60:40 to serve as the inner core water phase;

[0087] After 20 parts of ZIF-8 and dichloromethane are treated by 40 kHz ultrasonic for 30 minutes, 100 parts of PDMAEMA solution is added to continue to disperse and dissolve, forming an oil phase;

[0088] The oil phase and the inner core water phase are mixed and emulsified at a high speed of 10000 rpm for 8 minutes to form a primary emulsion;

[0089] The primary emulsion is added to an outer water phase containing polyvinyl alcohol, and emulsified by moderate stirring at 500 rpm for 20 minutes to form a multiple emulsion;

[0090] The stirring speed is kept at 300 rpm to promote solvent evaporation, and the capsule wall material is crosslinked and solidified at the oil-water interface, the crosslinking and solidification temperature is 40±2℃, the solidification time is 6h, centrifugation is performed for 15 minutes, the centrifugal speed is 3000 rpm, the solid phase is collected, and then washed with 4℃ pre-cooled deionized water for 3 times, followed by pre-freezing at-80℃, then freeze-drying at-50℃ under a vacuum of less than 10 Pa for 36h to obtain double-response intelligent microcapsule powder A.

[0091] Example 2

[0092] Hexadecyltrimethoxysilane and hydroxyl-terminated polydimethylsiloxane are mixed at a weight ratio of 70:30 to serve as the inner core water phase;

[0093] After 10 parts of ZIF-8 and dichloromethane are treated by 40 kHz ultrasonic for 30 minutes, 100 parts of PDMAEMA solution is added to continue to disperse and dissolve, forming an oil phase;

[0094] The above oil phase is mixed with the inner core water phase, and is emulsified at high speed for 5 min at 12000 rpm to form a primary emulsion;

[0095] The primary emulsion is added to an outer water phase containing polyvinyl alcohol, and is emulsified at medium speed for 30 min at 600 rpm to form a multiple emulsion;

[0096] Stirring is continuously performed at a rotation speed of 500 rpm to promote solvent volatilization, and the capsule wall material is crosslinked and solidified at the oil-water interface, with a crosslinking and solidification temperature of 40±2°C and a solidification time of 8 h. The solid phase is collected by centrifugation at 4000 rpm, washed with 4°C pre-cooled deionized water for 3 times, then pre-frozen at-80°C, and then freeze-dried at-50°C under a vacuum of less than 10 Pa for 24 h to obtain the double-response smart microcapsule powder B.

[0097] Example 3

[0098] 100 parts of the epoxy-modified silicone resin is mixed with 0.5 parts of the ROMP catalyst to obtain a pretreated matrix resin;

[0099] 5 parts of the smart microcapsule powder A prepared in Example 1, 100 parts of the pretreated matrix resin, 3 parts of KH-550 and 40 parts of a solvent are mixed to form a coating slurry, which is uniformly dispersed at 2000 rpm for 30 min;

[0100] The coating slurry is coated on the surface of the insulator substrate by air spraying at a spraying pressure of 0.3 MPa and a spraying distance of 20 cm. A step curing treatment is performed, in which the coating is first cured at 60°C for 1 h, then cured at 80°C for 2 h, and finally matured at room temperature for 24 h to form an anti-icing insulator coating.

[0101] Example 4

[0102] 100 parts of the epoxy-modified silicone resin is mixed with 1.5 parts of the ROMP catalyst to obtain a pretreated matrix resin;

[0103] 15 parts of the smart microcapsule powder B prepared in Example 2, 100 parts of the pretreated matrix resin, 5 parts of KH-560 and 60 parts of a solvent are mixed to form a coating slurry, which is uniformly dispersed at 2000 rpm for 30 min;

[0104] The coating slurry is coated on the surface of the insulator substrate by air spraying at a spraying pressure of 0.5 MPa and a spraying distance of 30 cm. A step curing treatment is performed, in which the coating is first cured at 60°C for 1 h, then cured at 80°C for 2 h, and finally matured at room temperature for 24 h to form an anti-icing insulator coating.

[0105] Example 5

[0106] Mixing 100 parts of the epoxy-modified silicone resin with 1.5 parts of the ROMP catalyst to obtain a pretreated matrix resin;

[0107] Mixing 15 parts of the smart microcapsule powder B prepared in Example 2, 100 parts of the pretreated matrix resin, 5 parts of FAS-17 and 60 parts of the solvent to form a coating slurry, which is uniformly dispersed at 2000 rpm for 30 minutes;

[0108] The coating slurry is coated on the surface of the insulator substrate by air spraying method at a spraying pressure of 0.5 MPa and a spraying distance of 30 cm. Through step curing treatment, it is first cured at 60°C for 1 hour, then cured at 80°C for 2 hours, and finally matured at room temperature for 24 hours to form an anti-icing insulator coating.

[0109] Comparative Example 1

[0110] The commercially available silicone rubber hydrophobic coating insulator is selected from Siemens, and the model is silicone rubber composite insulator.

[0111] Test Example:

[0112] According to the GB / T 30693-2014 standard, the static water contact angle and water rolling angle of the insulators of Examples 3 to 5 and Comparative Example 1 are tested, and the specific results are shown in Table 1.

[0113] According to the ASTM D3330 standard, the ice adhesion strength of the insulators of Examples 3 to 5 and Comparative Example 1 is tested, and the specific results are shown in Table 1.

[0114] According to the GB / T 23987-2009 standard, the anti-icing durability (contact angle after 1000h of ultraviolet aging) of the insulators of Examples 3 to 5 and Comparative Example 1 is tested, and the specific results are shown in Table 1.

[0115] The self-repairing efficiency of the insulators of Examples 3 to 5 and Comparative Example 1 is tested by microscope observation and contact angle test, and the specific results are shown in Table 1.

[0116] According to the IEC 60587 standard, the electrical tracking resistance performance of the insulators of Examples 3 to 5 and Comparative Example 1 is tested, and the specific results are shown in Table 1.

[0117]

[0118] Table 1 Statistical table of parameters of examples and comparative examples

[0119] Using the coating prepared in Example 3, three groups of identical coating samples were prepared, after the hydrophobicity was consumed by ultraviolet aging, one group was immersed in a neutral buffer solution, one group was immersed in a weakly acidic buffer solution with pH = 5.5 to simulate the ice melting water film, and the last group was immersed in a weakly acidic buffer solution with pH = 4.5 to simulate a strong acid environment, and the contact angle values of each group were measured regularly. The contact angle change data under different environments are as follows Figure 2 .

[0120] Figure 2 The contact angle change line graph of the coating in different pH environments.

[0121] In summary: the present application provides a dual-response intelligent microcapsule, an anti-icing insulator coating and a preparation process thereof, which utilizes the pH response characteristics of PDMAEMA and the acidic instability and nano-enhancing effect of ZIF-8 to construct an organic-inorganic hybrid capsule wall. Under normal conditions, the dense hybrid capsule wall allows the slow release of hydrophobic small molecules at a controllable rate, which migrates to the coating surface to dynamically supplement the low surface energy substances lost due to aging, realizing the "metabolism" of superhydrophobic performance and solving the problem of irreversible decay of the hydrophobic performance of traditional coatings. When the environment is slightly acidic, the PDMAEMA molecular chain is protonated and swells, causing the porosity of the capsule wall to increase, accelerating the release of hydrophobic small molecules, thereby enhancing the protection in advance and realizing the "early warning" response to harsh environments. When strong acid corrosion or mechanical damage produces microcracks, the ZIF-8 skeleton rapidly decomposes, causing structural rupture of the capsule wall, instant release of the core material, and restoration of hydrophobicity.

[0122] At the same time, the repair agent and the hydrophobic small molecule are co-encapsulated in the same microcapsule core, and the release behavior of the capsule wall is precisely controlled to make the repair function and the hydrophobic function closely coordinated in time and space. This not only simplifies the coating formula, but also ensures that the repair agent and the hydrophobic small molecule are released synchronously in time and space when the capsule wall is broken. The repair agent rapidly polymerizes to repair the physical cracks, while the hydrophobic small molecule immediately modifies the new interface to restore its superhydrophobicity. This "repairing and restoring" mechanism avoids the repaired area becoming a new performance short board, realizes the high coordination of the repair function and the hydrophobic function, and doubles the comprehensive protection efficiency.

[0123] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above examples, and the above examples and descriptions in the specification are only preferred examples of the present application and are not intended to limit the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A dual responsive smart microcapsule, characterized in that, The microcapsule has a core-shell structure, comprising: a core containing a hydrophobic small molecule and a repair agent; a capsule wall formed by hybridizing poly(N,N-dimethylaminoethyl methacrylate) and zeolite imidazolate framework material nanoparticles; wherein the capsule wall is configured to: under normal conditions, allow the hydrophobic small molecule to be released slowly at a first rate; under a weak acidic environment, due to the protonation swelling of poly(N,N-dimethylaminoethyl methacrylate), allow the hydrophobic small molecule to be released at a second rate higher than the first rate; under a strong acidic environment or mechanical damage, the capsule wall is broken, releasing the repair agent.

2. The dual responsive smart microcapsule according to claim 1, wherein, The hydrophobic small molecule is at least one of perfluorooctyltriethoxysilane or hexadecyltrimethoxysilane.

3. The dual responsive smart microcapsule of claim 1, wherein, The repair agent is at least one of dicyclopentadiene or hydroxyl-terminated polydimethylsiloxane.

4. The dual responsive smart microcapsule according to claim 2 or 3, wherein, In the core, the weight ratio of the hydrophobic small molecule to the repair agent is (60-70):(30-40).

5. The dual responsive smart microcapsule of claim 1, wherein, Based on 100 parts by weight of poly(N,N-dimethylaminoethyl methacrylate), the content of the zeolite imidazolate framework material nanoparticles is 10-20 parts by weight, and the capsule wall further contains 5-10 parts by weight of a crosslinking agent.

6. An anti-icing insulator coating comprising a coating matrix and a functional filler dispersed therein, characterized in that, The functional filler contains the dual-response smart microcapsule as claimed in any one of claims 1-5, and the mass fraction of the dual-response smart microcapsule in the coating matrix is 5%-15%.

7. The anti-icing insulator coating of claim 6, wherein, The coating matrix is an epoxy-modified silicone resin, and a catalyst for triggering polymerization of the repair agent is pre-dispersed in the epoxy-modified silicone resin.

8. A process for the preparation of an anti-icing insulator coating for the preparation of a coating as claimed in claim 6 or 7, characterized in that, The method comprises the following steps: ①Preparation of dual-response smart microcapsules by using a multiple emulsion-solvent evaporation method; ②Mixing of epoxy-modified silicone resin and catalyst in a certain proportion to obtain a pretreated matrix resin; ③Mixing of the smart microcapsules prepared in step ①, the pretreated matrix resin prepared in step ②, a silane coupling agent and a solvent to form a coating slurry; ④Coating of the coating slurry on the surface of the insulator substrate and curing treatment to form the anti-icing insulator coating; wherein the coating is performed by using an air spraying method, the spraying pressure is 0.3-0.5 MPa, and the spraying distance is 20-30 cm; and the curing treatment is specifically a stepwise temperature rising curing, i.e., curing at 60°C for 1 hour and then curing at 80°C for 2 hours.

9. The process for the preparation of an anti-icing insulator coating according to claim 8, characterized in that, The multiple emulsion-solvent evaporation method in step ① specifically comprises the following steps: ①Mixing of a hydrophobic small molecule and a repair agent in a certain proportion as an aqueous phase of a core; ②Dissolution or dispersion of poly(N,N-dimethylaminoethyl methacrylate) and zeolite imidazolate framework material nanoparticles in dichloromethane in a certain proportion to form an oil phase; ③Mixing of the oil phase of step ② and the aqueous phase of the core of step ① and high-speed shearing emulsification to form a primary emulsion; ④Addition of the primary emulsion to an external aqueous phase containing polyvinyl alcohol and medium-speed stirring emulsification to form a multiple emulsion; ⑤Continuous stirring to evaporate the solvent, crosslinking and curing of the capsule wall material at the oil-water interface, and post-treatment to obtain dual-response smart microcapsule powder; Specifically, the stirring rate is 300-500 rpm, the crosslinking and curing temperature is 40±2°C, and the curing time is 6-8 hours.

10. The process for the preparation of an anti-icing insulator coating according to claim 9, characterized in that, The post-treatment in step (v) comprises centrifugation at 3000-4000 rpm for 10-15 min, collection of the solid phase, washing 3 times with deionized water pre-cooled to 4°C, subsequent pre-freezing to -80°C, and then freeze-drying at -50°C under a vacuum of less than 10 Pa for 24-36 h.

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