Preparation method of single-component self-drying siloxane anti-icing super-hydrophobic oleophobic coating

Abstract

The invention discloses a preparation method of a single-component self-drying siloxane anti-icing super-hydrophobic and super-oleophobic coating, and belongs to the technical field of power transmission line functional coatings. The coating is prepared from the following raw materials in percentage by mass: 10-20% of siloxane resin, 30-40% of hydrophobic modified micro-nano powder, 45-55% of a diluent, 0.1-0.3% of a defoaming agent and 0.3-0.7% of a coupling agent. The hydrophobic modified micro-nano powder is formed by mixing aluminum oxide particles modified by perfluorodecyl trimethoxy silane and tin antimony oxide particles according to a proportion. The preparation method mainly comprises the following steps: respectively preparing two modified particles, mixing to obtain powder, mixing the powder with the resin, the diluent and the like, and grinding. Through a specific formula process, the coating has excellent super-hydrophobic and oleophobic properties, high adhesive force and strong weather resistance, solves the problems of poor mechanical durability and easy aging and shedding of the existing anti-icing coating, and is suitable for icing protection of power transmission lines in sub-cold regions such as high-speed rail power transmission networks and the like.

Description

Technical Field

[0001] This invention relates to the field of functional coatings for power transmission lines, and in particular to a method for preparing a single-component, self-drying siloxane anti-icing superhydrophobic and oleophobic coating. Background Technology

[0002] In sub-cold regions, freezing rain is common in winter, causing significant inconvenience to many power transmission lines, especially high-speed rail networks, affecting normal railway operations, and in severe cases, even leading to transportation disruptions. Therefore, in these areas, we must study how to prevent line icing, or how to make it easier to remove ice, and how to prevent ice-covered lines from accumulating and dancing, in order to mitigate the impact of icing on railway transportation.

[0003] Most existing superhydrophobic materials face a key bottleneck in practical applications: poor mechanical durability. Their micro-nano rough surface structures are extremely fragile and easily damaged by friction, scratches, raindrop impacts, or UV aging, leading to a rapid loss of superhydrophobicity. Furthermore, many superhydrophobic coatings have weak adhesion to the substrate and are prone to peeling off under complex operating conditions. Developing a coating that possesses both excellent superhydrophobic and anti-icing properties, as well as good mechanical stability and durability, has become a pressing technical challenge in this field. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of poor mechanical durability, weak adhesion, easy aging and peeling, and lack of oleophobic function of existing superhydrophobic anti-icing coatings, and to propose a method for preparing a single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A one-component, self-drying, siloxane-based anti-icing superhydrophobic and oleophobic coating is made from the following raw materials in the indicated weight percentages:

[0007] 10-20% siloxane resin;

[0008] Hydrophobic modified micro / nano powders 30-40%;

[0009] Diluent 45-55%;

[0010] Defoamer 0.1-0.3%;

[0011] Coupling agent 0.3-0.7%;

[0012] The hydrophobic modified micro / nano powder is composed of alumina particles modified with perfluorodecyltrimethoxysilane and tin-antimony oxide particles modified with perfluorodecyltrimethoxysilane in a mass ratio of 0.5:1 to 2:1.

[0013] In some embodiments, the mass ratio of modified alumina particles to modified tin-antimony oxide particles in the hydrophobic modified micro / nano powder is 1:1.

[0014] In some embodiments, the siloxane resin is SJ-1850 self-drying siloxane resin, the diluent is PMA solvent, and the coupling agent is KH570.

[0015] A hydrophobically modified micro / nano powder for use in the above-mentioned coatings, wherein the raw materials for preparation include, by mass percentage:

[0016] Nano-alumina or nano-tin-antimony oxide powder 20-45%;

[0017] Anhydrous ethanol 50-77%;

[0018] 1-3% perfluorodecyltrimethoxysilane;

[0019] Ammonia solution 0.5-1.5%.

[0020] In some embodiments, the raw materials for preparation include, by mass percentage: 30.24% nano-alumina or nano-tin antimony oxide powder, 65.7% anhydrous ethanol, 2.56% perfluorodecyltrimethoxysilane, and 1.5% ammonia.

[0021] A method for preparing hydrophobically modified micro / nano powders includes the following steps:

[0022] Perfluorodecyltrimethoxysilane was added to anhydrous ethanol, and ammonia was slowly added while stirring until homogeneous to obtain a mixed solution.

[0023] Nano-alumina or nano-tin-antimony oxide powder is added to the mixed solution and dispersed at 15-25°C and a rotation speed of 600-1000 rpm for 20-40 minutes to obtain the mixed solution.

[0024] The mixture is dried, ground, and sieved to obtain the hydrophobic modified micro / nano powder.

[0025] A method for preparing a one-component, self-drying siloxane anti-icing superhydrophobic and oleophobic coating includes the following steps:

[0026] S1: Modified alumina particles and modified tin-antimony oxide particles were prepared according to the above method, and the two were mixed in proportion to obtain hydrophobic modified micro-nano powder;

[0027] S2: Add the siloxane resin to the diluent and stir at 400-600 rpm at 15-25℃ to obtain the resin dilution.

[0028] S3: Add the hydrophobic modified micro / nano powder, defoamer and coupling agent in the proportions described in claim 1 or 2 to the resin dilution, and stir at 1000-1500 rpm for 20-40 minutes at 15-25°C to obtain the coating mixture.

[0029] S4: Grind the coating mixture to obtain the anti-icing superhydrophobic and oleophobic coating.

[0030] In some embodiments, in step S4, the grinding process is performed at a rotation speed of 2500-3500 rpm for 30-50 minutes.

[0031] A method for preparing a one-component, self-drying siloxane anti-icing superhydrophobic and oleophobic coating includes the following steps:

[0032] S1: Preparation of modified alumina particles: Alumina particles are dispersed in anhydrous ethanol, ammonia and perfluorodecyltrimethoxysilane are added, and the mixture is reacted at 50-70℃ for 1-3 hours. Then the temperature is raised to 70-90℃ and the reaction is continued for 1-3 hours until a paste is formed. After separation, washing and drying, modified alumina particles are obtained.

[0033] S2: Preparation of modified tin-antimony oxide particles: Disperse tin-antimony oxide particles in anhydrous ethanol, add ammonia and perfluorodecyltrimethoxysilane, react at 50-70℃ for 1-3 hours, then raise the temperature to 70-90℃ and continue to react for 1-3 hours until a paste is formed. After separation, washing and drying, the modified tin-antimony oxide particles are obtained.

[0034] S3: Preparation of coating slurry: Mix 25-35 parts by weight of the modified alumina particles, 5-15 parts by weight of the modified tin-antimony oxide particles, 35-45 parts by weight of siloxane resin, 10-20 parts by weight of diluent, 0.005-0.015 parts by weight of defoamer, and 0.005-0.015 parts by weight of coupling agent, and then perform ultrasonic dispersion.

[0035] S4: Grind the coating slurry to obtain the anti-icing superhydrophobic and oleophobic coating.

[0036] Compared with the prior art, the present invention provides a method for preparing a single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating, which has the following beneficial effects.

[0037] 1. The anti-icing superhydrophobic coating and oleophobic coating prepared by this invention have strong adhesion to the substrate, greatly improved aging resistance, are not easily brittle after freeze-thaw cycles, and have both hydrophobic and oleophobic functions.

[0038] 2. This invention utilizes perfluorosilane-modified alumina and antimony tin oxide (ATO) micro-nano composite powders to create a coating exhibiting extremely high water contact angles (up to 158° and above) and extremely low roll-off angles (down to 4°), while also possessing oleophobic properties. This dual oleophobicity makes it difficult for ice, water, and oily contaminants to adhere stably to the coating surface, significantly improving anti-icing and anti-pollution capabilities.

[0039] 3. This invention uses SJ-1850 self-drying siloxane resin as the film-forming material, which possesses excellent flexibility and adhesion. Furthermore, the bridging effect of KH570 coupling agent enhances the chemical bonding between the inorganic powder and organic resin in the coating, as well as between the coating as a whole and the substrate (such as metal wires). Testing showed that the adhesion strength between the coating and the substrate reached 2.0 MPa, far exceeding that of ordinary coatings. Simultaneously, the addition of composite powder and thorough grinding processes result in a dense coating structure, effectively resisting physical damage such as friction and scratches, and exhibiting excellent wear resistance.

[0040] Other advantages, objectives and features of the invention will be set forth in part in the description which follows; and in part will be apparent to those skilled in the art upon examination of the following description; or may be learned from practice of the invention. Attached Figure Description

[0041] Figure 1 This is a contact angle diagram of the surface of the coating material prepared in Example 2 of the present invention.

[0042] Figure 2 This is a contact angle diagram of the surface of the coating material prepared in Comparative Example 8 of the present invention. Detailed Implementation

[0043] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0044] Example 1

[0045] This invention discloses a method for preparing a single-component, self-drying siloxane anti-icing superhydrophobic and oleophobic coating, the specific steps of which are as follows:

[0046] S1. Preparation of modified alumina particles

[0047] S11. Take 100g of alumina particles with a particle size of 100μm and disperse them in 200mL of 99% anhydrous ethanol;

[0048] S12. Add ammonia to the above dispersion and stir for 5 minutes at room temperature using a homogenizer.

[0049] S13. Add 8g of perfluorodecyltrimethoxysilane, raise the system temperature to 60℃, and stir the reaction with a magnetic stirrer for 2 hours.

[0050] S14. After the reaction is complete, raise the temperature to 80°C and continue stirring for 2 hours until the system becomes a paste.

[0051] S15. The paste-like product is centrifuged, washed with ethanol, and then dried in a vacuum drying oven at 100℃ for 6 hours to obtain white powdery modified alumina particles.

[0052] S2. Preparation of modified ATO (antimony tin oxide) particles

[0053] S21. Take 40g of ATO particles with a particle size of 10nm and disperse them in 200mL of 99% anhydrous ethanol;

[0054] S22. Add ammonia water to the above dispersion and stir for 5 minutes at room temperature using a homogenizer;

[0055] S23. Add 10g of perfluorodecyltrimethoxysilane, raise the system temperature to 60℃, and stir the reaction with a magnetic stirrer for 2 hours.

[0056] S24. After the reaction is complete, raise the temperature to 80°C and continue stirring for 2 hours until the system becomes a paste.

[0057] S25. The paste-like product is centrifuged, washed with ethanol, and then dried in a vacuum drying oven at 100℃ for 6 hours to obtain white powdery modified ATO particles.

[0058] S3, Prepare coating slurry

[0059] Weigh 25 parts by weight of the above-mentioned modified alumina particles, 10 parts by weight of modified ATO particles, 40 parts by weight of SJ-1850 self-drying siloxane resin, 15 parts by weight of PMA solvent, 0.01 parts by weight of BYK-LPD25789 defoamer, and 0.01 parts by weight of KH570 coupling agent, and add them together to an ultrasonic cell disruptor. Ultrasonic treatment is carried out at 600W power for 1 hour, with intermittent stirring during the process, to obtain a uniformly dispersed milky white slurry.

[0060] S4, Grinding Coating Slurry

[0061] The prepared milky white slurry was added to a pneumatic basket mill and ground at 1400 rpm for 2 hours to obtain the finished anti-icing coating.

[0062] The coating prepared in this embodiment exhibits excellent superhydrophobicity (contact angle 158°, roll-off angle 4°) and good wear resistance.

[0063] This invention also discloses another method for preparing a one-component, self-drying siloxane anti-icing superhydrophobic and oleophobic coating, the specific steps of which are as follows:

[0064] S1. Preparation of modified alumina particles

[0065] S11. Prepare raw materials according to the following percentage by mass: nano-alumina 30.24%, anhydrous ethanol 65.7%, perfluorodecyltrimethoxysilane 2.56%, ammonia 1.5%;

[0066] S12. First, add perfluorodecyltrimethoxysilane to anhydrous ethanol, then slowly add ammonia water and stir until well mixed.

[0067] S13. Add nano-alumina to the above mixture, control the temperature at about 20℃, and disperse at a speed of 800 rpm for 30 minutes to obtain nano-alumina mixture.

[0068] S2. Preparation of modified ATO (antimony tin oxide) particles

[0069] S21. Prepare raw materials according to the following mass percentages: 30.24% nano-ATO powder, 65.7% anhydrous ethanol, 2.56% perfluorodecyltrimethoxysilane, and 1.5% ammonia.

[0070] S22. First, add perfluorodecyltrimethoxysilane to anhydrous ethanol, then slowly add ammonia water and stir until well mixed.

[0071] S23. Add nano-ATO powder to the above mixture, control the temperature at about 20℃, and disperse at a speed of 800 rpm for 30 minutes to obtain nano-ATO mixture.

[0072] S3. Preparation of mixed powders

[0073] S31. The nano-alumina mixture and nano-ATO mixture prepared above are dried at 100°C for 2 hours.

[0074] S32. Grind and sieve the two dried materials separately.

[0075] S33. The modified alumina particles after grinding and sieving are mixed with modified ATO particles at a mass ratio of 1:1 to obtain hydrophobic modified micro-nano powder.

[0076] Example 2

[0077] This embodiment uses the hydrophobically modified micro / nano powder prepared in Example 1 as raw material to prepare a single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating. The specific steps are as follows:

[0078] Raw material ratio (mass percentage): SJ-1850 siloxane resin 15%, hydrophobic modified micro-nano powder (prepared in Example 1) 35%, diluent PMA 50%, defoamer 0.2%, coupling agent KH570 0.5%.

[0079] Preparation steps:

[0080] Step 1: First, add SJ-1850 siloxane resin to diluent PMA, control the temperature at 20℃, and stir at 500 rpm for 5 minutes to obtain a resin dilution mixture.

[0081] Step 2: Add hydrophobic modified micro-nano powder, defoamer and coupling agent KH570 to the above resin dilution mixture, maintain the temperature at 20℃, adjust the speed to 1200 rpm, stir for 30 minutes to obtain the anti-icing coating mixture.

[0082] Step 3: Place the anti-icing coating mixture in a grinding device and grind it at 3000 rpm for 40 minutes to obtain a single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating.

[0083] To verify the significance of the technical solution of this invention, the following comparative examples are provided:

[0084] It should be noted that the composition and preparation method of Comparative Examples 1-4 are basically the same as those of Example 1, only the mass percentage of each component is changed, as follows:

[0085] Comparative Example 1: The content of nano-alumina was 20.16%, the content of anhydrous ethanol was 76.81%, the content of perfluorodecyltrimethoxysilane was 1.89%, and the content of ammonia was 1.14%.

[0086] Comparative Example 2: 30% nano-alumina, 67.52% anhydrous ethanol, 0.98% perfluorodecyltrimethoxysilane, and 1.5% ammonia; nano-ATO powder was prepared in the same proportions as above.

[0087] Comparative Example 3: 31% nano-alumina, 67.51% anhydrous ethanol, 0.98% perfluorodecyltrimethoxysilane, and 0.51% ammonia; nano-ATO powder was prepared in the same proportions as above.

[0088] Comparative Example 4: 45.36% nano-alumina, 50.51% anhydrous ethanol, 2.61% perfluorodecyltrimethoxysilane, and 1.52% ammonia; nano-ATO powder was prepared in the same proportions as above.

[0089] The composition and preparation method of Comparative Examples 5-8 are basically the same as those of Example 2, except that the hydrophobic modified micro / nano powders used are prepared from Comparative Examples 1-4, specifically:

[0090] Comparative Example 5: The difference is that the hydrophobic modified micro / nano powder was prepared as in Comparative Example 1.

[0091] Comparative Example 6: The difference is that the hydrophobically modified micro / nano powder was prepared as in Comparative Example 2.

[0092] Comparative Example 7: The difference is that the hydrophobically modified micro / nano powder was prepared as in Comparative Example 3.

[0093] Comparative Example 8: The difference is that the hydrophobically modified micro / nano powder was prepared as in Comparative Example 4.

[0094] The hydrophobic properties of the single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coatings prepared in Example 2 and Comparative Examples 5-8 were tested using a contact angle meter. The test results are shown in Table 1. The contact angle diagram of the coating material prepared in Example 2 is shown below. Figure 1 The contact angle diagram of the coating material surface prepared in Comparative Example 8 is shown in Figure 8. Figure 2 .

[0095] Table 1 shows the effect of different hydrophobically modified micro / nano powders on the hydrophobic properties of the coating material:

[0096] raw material Example 2 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Hydrophobically modified micro / nano powders (g) 30.24 20.16 30 31 45.36 Anhydrous ethanol (g) 65.7 76.81 67.52 67.51 50.51 Perfluorodecyltrimethoxysilane (g) 2.56 1.89 0.98 0.98 2.61 Ammonia water (g) 1.5 1.14 1.5 0.51 1.52 Contact angle of water on a surface (°) 158° 126° 112° 98° 161°

[0097] Table 1

[0098] The aging resistance of the single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating of Example 2 was tested using a UV aging test chamber. The aging resistance time reached more than 2000 hours, and at 1000 hours, the water contact angle on its surface decreased by only ≤5°.

[0099] The adhesion performance of the single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating prepared in Example 2 was tested using an adhesive strength tester, and the adhesive strength reached 2.0 MPa. It exhibits strong adhesion and is not easily detached.

[0100] Conclusion: As can be seen from Table 1, the single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating prepared in Example 2 has a water contact angle of 158° on its surface, which is closest to that of the single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating prepared in Comparative Example 8. However, the amount of hydrophobic modified micro-nano powder used in Comparative Example 8 is 1.5 times that of Example 2, resulting in a higher cost.

[0101] In summary, the single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating prepared in Example 2 is cost-effective while possessing superhydrophobic capabilities, achieving an anti-icing effect. Furthermore, its adhesion and weather resistance far exceed the levels of existing coatings in the industry, effectively solving the icing problem of power transmission lines (especially high-speed rail power grids) in sub-cold regions. This represents a significant improvement over existing technologies and enhances its ability to withstand continuous outdoor use.

[0102] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0103] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

Claims

1. A one-component, self-drying siloxane anti-icing superhydrophobic and oleophobic coating, characterized in that, Made from the following raw materials by weight percentage: 10-20% siloxane resin; Hydrophobic modified micro / nano powders 30-40%; Diluent 45-55%; Defoamer 0.1-0.3%; Coupling agent 0.3-0.7%; The hydrophobic modified micro / nano powder is composed of alumina particles modified with perfluorodecyltrimethoxysilane and tin-antimony oxide particles modified with perfluorodecyltrimethoxysilane in a mass ratio of 0.5:1 to 2:

1.

2. The single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating according to claim 1, characterized in that, In the hydrophobic modified micro / nano powder, the mass ratio of modified alumina particles to modified tin-antimony oxide particles is 1:

1.

3. The single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating according to claim 1, characterized in that, The siloxane resin is SJ-1850 self-drying siloxane resin, the diluent is PMA solvent, and the coupling agent is KH570.

4. A hydrophobically modified micro / nano powder for use in the coating according to any one of claims 1-3, characterized in that, Its raw materials, by mass percentage, include: Nano-alumina or nano-tin-antimony oxide powder 20-45%; Anhydrous ethanol 50-77%; 1-3% perfluorodecyltrimethoxysilane; Ammonia solution 0.5-1.5%.

5. The hydrophobically modified micro / nano powder according to claim 4, characterized in that, The raw materials for its preparation include, by mass percentage: 30.24% nano-alumina or nano-tin antimony oxide powder, 65.7% anhydrous ethanol, 2.56% perfluorodecyltrimethoxysilane, and 1.5% ammonia.

6. A method for preparing the hydrophobically modified micro / nano powder according to claim 4 or 5, characterized in that, Includes the following steps: Perfluorodecyltrimethoxysilane was added to anhydrous ethanol, and ammonia was slowly added while stirring until homogeneous to obtain a mixed solution. Nano-alumina or nano-tin-antimony oxide powder is added to the mixed solution and dispersed at 15-25°C and a rotation speed of 600-1000 rpm for 20-40 minutes to obtain the mixed solution. The mixture is dried, ground, and sieved to obtain the hydrophobic modified micro / nano powder.

7. A method for preparing a single-component, self-drying siloxane anti-icing superhydrophobic and oleophobic coating, characterized in that, Includes the following steps: S1: Modified alumina particles and modified tin-antimony oxide particles are prepared separately according to the method described in claim 6, and the two are mixed in a certain proportion to obtain hydrophobic modified micro-nano powder; S2: Add the siloxane resin to the diluent and stir at 400-600 rpm at 15-25℃ to obtain the resin dilution. S3: Add the hydrophobic modified micro / nano powder, defoamer and coupling agent in the proportions described in claim 1 or 2 to the resin dilution, and stir at 1000-1500 rpm for 20-40 minutes at 15-25°C to obtain the coating mixture. S4: Grind the coating mixture to obtain the anti-icing superhydrophobic and oleophobic coating.

8. The preparation method of the single-component self-drying siloxane anti-icing superhydrophobic and oleophobic coating according to claim 7, characterized in that, In step S4, the grinding process is performed at a speed of 2500-3500 rpm for 30-50 minutes.

9. A method for preparing a single-component, self-drying siloxane anti-icing superhydrophobic and oleophobic coating, characterized in that, Includes the following steps: S1: Preparation of modified alumina particles: Alumina particles are dispersed in anhydrous ethanol, ammonia and perfluorodecyltrimethoxysilane are added, and the mixture is reacted at 50-70℃ for 1-3 hours. Then the temperature is raised to 70-90℃ and the reaction is continued for 1-3 hours until a paste is formed. After separation, washing and drying, modified alumina particles are obtained. S2: Preparation of modified tin-antimony oxide particles: Disperse tin-antimony oxide particles in anhydrous ethanol, add ammonia and perfluorodecyltrimethoxysilane, react at 50-70℃ for 1-3 hours, then raise the temperature to 70-90℃ and continue to react for 1-3 hours until a paste is formed. After separation, washing and drying, the modified tin-antimony oxide particles are obtained. S3: Preparation of coating slurry: Mix 25-35 parts by weight of the modified alumina particles, 5-15 parts by weight of the modified tin-antimony oxide particles, 35-45 parts by weight of siloxane resin, 10-20 parts by weight of diluent, 0.005-0.015 parts by weight of defoamer, and 0.005-0.015 parts by weight of coupling agent, and then perform ultrasonic dispersion. S4: Grind the coating slurry to obtain the anti-icing superhydrophobic and oleophobic coating.

10. The application of a single-component self-drying siloxane anti-icing superhydrophobic oleophobic coating as described in any one of claims 1-3 in anti-icing of power transmission lines or high-speed rail power transmission networks.

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