Stable super-hydrophobic flexible material as well as preparation method and application thereof

Abstract

The invention discloses a stable super-hydrophobic flexible material as well as a preparation method and application thereof. Immersing a carbon fiber material into the nano-zinc oxide solution to obtain a carbon fiber material loaded with nano-zinc oxide; immersing the carbon fiber material loaded with the nano zinc oxide into a zinc salt solution, then carrying out hydrothermal reaction, and then carrying out annealing treatment to obtain a carbon fiber material loaded with a zinc oxide coating; and modifying polysiloxane on the surface of the carbon fiber material loaded with the zinc oxide coating to obtain the stable super-hydrophobic flexible material. The invention relates to a zinc oxide nano array generation technology based on hydrothermal reaction phase buffer stability, which is used for controlling the form of zinc oxide during in-situ generation on the surface of a carbon fiber. On the basis, the surface of the inorganic nano coating is modified with a low-surface-energy organic silicon substance, and the super-hydrophobic composite coating is obtained.

Description

Technical Field

[0001] This invention belongs to the field of new materials technology and relates to a superhydrophobic material, specifically a stable superhydrophobic flexible material and its preparation method and application. Background Technology

[0002] Superhydrophobic surfaces, as materials with extremely strong anti-wetting capabilities, exhibit multiple functions such as self-cleaning, maintaining dryness, drag reduction, and liquid barrier while allowing air permeability, showing broad application prospects in industry, especially in high-precision fields. In outdoor environments, the stable performance of superhydrophobic surfaces is particularly important, especially in conditions of high humidity and extreme temperature differences. The structure and morphology of nanomaterials have a significant impact on their performance and applications. Preparing nanocrystalline materials with specific structures and morphologies is crucial for developing new areas of nanomaterial performance. Among numerous nanomaterials, the nanostructure of zinc oxide has attracted widespread interest.

[0003] In the hydrothermal synthesis of zinc oxide, ammonia acts as a key complexing agent, regulating the balance of zinc ion complexation and decomposition to achieve crystal nucleation and growth. Current mainstream techniques involve the direct reaction of zinc chloride with ammonia, optimizing morphology through pH adjustment and ultrasonic pretreatment. However, existing methods suffer from the following drawbacks: uncontrollable ammonia decomposition: Under high-temperature (>90℃) hydrothermal conditions, rapid ammonia decomposition leads to drastic pH fluctuations in the reaction system, triggering the formation of colloidal byproducts of zinc hydroxide and reducing product purity. Summary of the Invention

[0004] To address the issues of uncontrollable reactions and uneven surface morphology in existing in-situ zinc oxide nanoarray generation technologies, this invention discloses a controllable in-situ growth coating of zinc oxide on carbon fiber surfaces and a superhydrophobic flexible material (such as carbon cloth). This process forms a zinc oxide nanocoating layer on the carbon fiber surface and is based on a hydrothermal reaction phase buffering and stabilization-based zinc oxide nanoarray generation technology, enabling controllable morphology of zinc oxide during in-situ generation on the carbon fiber surface. Furthermore, by modifying the inorganic nanocoating surface with a low surface energy organosilicon material, a superhydrophobic composite coating is obtained.

[0005] The present invention adopts the following technical solution.

[0006] A method for preparing a stable superhydrophobic flexible material includes the following steps: (1) Immerse carbon fiber material in nano zinc oxide solution to obtain carbon fiber material loaded with nano zinc oxide; (2) The carbon fiber material loaded with nano zinc oxide is immersed in a zinc salt solution, then subjected to hydrothermal reaction, and then annealed to obtain the carbon fiber material loaded with zinc oxide coating. (3) Polysiloxane was modified on the surface of carbon fiber material loaded with zinc oxide coating to obtain a stable superhydrophobic flexible material.

[0007] A method for preparing a stable hydrophilic flexible material includes the following steps: (1) Immerse carbon fiber material in nano zinc oxide solution to obtain carbon fiber material loaded with nano zinc oxide; (2) The carbon fiber material loaded with nano zinc oxide is immersed in a zinc salt solution, then subjected to hydrothermal reaction, and then annealed to obtain a carbon fiber material loaded with zinc oxide coating, which is a stable hydrophilic flexible material.

[0008] In this invention, the nano zinc oxide solution comprises nano zinc oxide and a small molecule alcohol solvent; wherein the small molecule alcohol solvent includes ethanol. Preferably, the concentration of nano zinc oxide in the nano zinc oxide solution is 1–10 mg / mL, more preferably 3–6 mg / mL.

[0009] In this invention, carbon fiber material is immersed in a nano-zinc oxide solution for 1 to 15 minutes, then removed and dried to obtain carbon fiber material loaded with nano-zinc oxide. In this invention, the zinc salt solution includes water-soluble zinc salt, ammonia, additives, and water. The additives include one or more of ethylenediamine hydrochloride, ammonium chloride, and betaine.

[0010] In this invention, the zinc salt solution has a zinc salt concentration of 10–50 g / L, a volume ratio of ammonia to water of (0.5–1.5):20, and an additive concentration of 0.05–0.2 mol / L; preferably, the zinc salt solution has a zinc salt concentration of 20–40 g / L, a volume ratio of ammonia to water of (0.8–1.2):20, and an additive concentration of 0.08–0.15 mol / L.

[0011] In this invention, the hydrothermal reaction temperature is 100℃±10℃, and the time is 90~120 minutes.

[0012] In this invention, the annealing temperature is 60℃±10℃ and the time is 100~150 minutes.

[0013] In this invention, carbon fiber material with a zinc oxide coating is immersed in a PDMS solution, and polysiloxane is modified on the surface of the carbon fiber material with the zinc oxide coating to obtain a stable superhydrophobic flexible material. Specifically, the carbon fiber material with a zinc oxide coating is immersed in a PDMS solution for 5 to 30 minutes, then removed and dried, thereby modifying the surface of the carbon fiber material with a zinc oxide coating to obtain a stable superhydrophobic flexible material.

[0014] In this invention, the PDMS solution includes PDMS, octadecylamine, and an organic solvent; wherein the organic solvent includes n-pentane.

[0015] In this invention, the concentration of PDMS in the PDMS solution is 30-50 g / L, and the concentration of octadecylamine is 5-20 g / L.

[0016] In this invention, carbon fiber materials include carbon fiber fabrics, such as carbon cloth.

[0017] This invention discloses stable superhydrophobic flexible materials and stable hydrophilic flexible materials prepared according to the above preparation method.

[0018] This invention discloses the application of the above-mentioned stable superhydrophobic flexible material and stable hydrophilic flexible material in the preparation of hydrophobic products.

[0019] This invention discloses a hydrophobic product comprising the aforementioned stable superhydrophobic flexible material.

[0020] This invention discloses a zinc oxide nanoarray generation technology based on hydrothermal reaction phase buffering stability. In a high-temperature hydrothermal environment where zinc chloride is used as the zinc source to generate a zinc oxide coating in situ on the surface of carbon fibers, the NH3 / NH4 ratio can be dynamically balanced. + Concentration is controlled based on the morphology of zinc oxide generated in situ on the carbon fiber surface; and the process of in situ zinc oxide generation on the fiber surface is simplified.

[0021] The technique for controlling the in-situ formation of zinc oxide on the surface of carbon fibers disclosed in this invention exhibits good stability during the hydrothermal reaction of ammonia decomposition and zinc source, suppressing excessive NH3 release and overcoming the instability of the reaction system in current traditional processes. In particular, the preferred additives of this invention can suppress excessive NH3 release through competitive coordination, maintaining the stability of Zn²⁺. + The complexation stability allows for control over the zinc oxide formation process during the hydrothermal reaction, as well as the regulation of zinc oxide morphology and particle size. Furthermore, this invention can eliminate side reactions during the zinc source hydrothermal reaction, reducing the formation of zinc hydroxide colloids and improving the purity of zinc oxide crystals. This also helps control the growth morphology of the zinc oxide coating on the fiber surface. Importantly, the process of this invention is completed within 8-12 hours, achieving controllable preparation of zinc oxide through two steps: hydrothermal and low-temperature annealing. The process involves single-batch feeding, eliminating the need for ammonia replenishment and subsequent sintering steps, enabling continuous hydrothermal synthesis of zinc oxide on the fiber surface, which is beneficial for industrial production applications. Attached Figure Description

[0022] Figure 1 SEM images of zinc oxide prepared in Examples 1 to 3: a, d Example 1, b, e Example 2, c, f Example 3.

[0023] Figure 2 XPS spectra of zinc oxide-coated carbon cloth prepared in Example 1: a. Overall spectrum, b. Zn 2p spectrum, c. O1s spectrum.

[0024] Figure 3 XRD patterns a and infrared spectra b of the carbon fiber surface zinc oxide coating prepared in Example 1 before and after PDMS modification (compared to the original carbon cloth).

[0025] Figure 4 The EDS spectrum of the zinc oxide-coated carbon cloth prepared in Example 1 after secondary modification is shown.

[0026] Figure 5 The fiber morphology under a super depth-of-field microscope: a) original carbon cloth, b) hydrophobic carbon cloth prepared in Example 1.

[0027] Figure 6 Figure 1 shows the carbon cloth (WCA) prepared in Example 1 before and after polysiloxane modification with zinc oxide coating: a) Comparison of carbon cloth after zinc oxide modification and secondary modification; b) Comparison of carbon cloth before and after multiple soaping washes; c) Carbon cloth after different number of rubbing cycles.

[0028] Figure 7 For the comparison of surface anti-fouling of carbon cloth prepared by zinc oxide coating and polysiloxane modification in Example 1: a) untreated carbon cloth, b) hydrophobic carbon cloth treated with zinc oxide and PDMS.

[0029] Figure 8 For the comparison of self-cleaning test of carbon cloth surface before and after zinc oxide coating and polysiloxane modification in Example 1: a) untreated carbon cloth, b) hydrophobic carbon cloth treated with zinc oxide and PDMS.

[0030] Figure 9 The diagrams are WCA diagrams for Examples 1 to 3.

[0031] Figure 10 WCA diagrams for comparative examples one through three. Detailed Implementation

[0032] This invention involves adding reagents and ammonia to a hydrothermal reaction solution containing a zinc source. The reagents include ethylenediamine hydrochloride, ammonium chloride, and betaine (also known as trimethylglycine). Then, carbon fiber / carbon cloth coated with zinc oxide is immersed in the reaction solution at a bath ratio of 20 and reacted in a reactor at 100°C for 2 hours without the need for external ammonia replenishment or pressurization equipment. After the reaction is completed, the carbon fiber material is annealed at 60°C for 2 hours, allowed to cool naturally, and then washed with water at room temperature until the washing solution is neutral. After drying, zinc oxide-coated carbon fiber / carbon cloth is obtained.

[0033] The following specific experiments illustrate the technological advancements of this invention. The raw materials used are existing products, and the specific preparation operations and performance testing follow conventional techniques. Specifically, the PDMS used is 100cs, sourced from Dongguan Kangjin New Materials Co., Ltd.; the carbon cloth (carbon fiber fabric) is EDP850, 130 g / m³. 2Thickness 0.5 mm, purchased from Jingzhou Haote New Materials Co., Ltd.

[0034] Example 1 (1) Carbon cloth pretreatment Weigh 0.2 g of nano zinc oxide (D90, 200 nm) powder, add it to 40 mL of 95% ethanol aqueous solution, ultrasonically disperse for 20 minutes, then immerse carbon cloth (2 cm × 2 cm), and ultrasonically treat for 5 minutes; after completion, take out the carbon cloth and dry it in an oven at 60℃ to obtain carbon cloth loaded with zinc oxide layer.

[0035] (2) In-situ reaction and post-treatment Weigh 0.6 g of zinc chloride and dissolve it in 20 mL of deionized water (zinc chloride concentration 30 g / L). Then add 1 mL of ammonia water (28 wt%) and 0.23 g of betaine to prepare a zinc ion precursor solution. The carbon cloth loaded with zinc oxide layer was immersed in zinc ion precursor solution with a bath ratio of 20, and then reacted at 100℃ for 2 hours. After the reaction was completed, it was naturally cooled to room temperature, then washed with water three times (50 mL), and finally placed in a drying oven and annealed at 60℃ for 2 hours to obtain a carbon cloth product with zinc oxide coating layer grown in situ on the fiber surface (zinc oxide coated carbon cloth).

[0036] Betaine (trimethylglycine) neutralizes NH4 + / OH - Concentration fluctuations maintain a stable pH range; betaine competes with zinc ions for coordination to form a weak complex (ZnBetaine), thus mitigating [Zn(NH3)4]... 2+ Excessive dissociation of NH3 is inhibited, and explosive release of NH3 is prevented, while avoiding the introduction of byproducts.

[0037] (3) Zinc oxide surface modification A low surface energy material was applied to the zinc oxide surface through secondary modification with polysiloxane (PDMS). The zinc oxide-coated carbon cloth was then treated with a prepared hydrophobic coating impregnation solution at a bath ratio of 50. The impregnation solution was prepared by dissolving PDMS (2 g) and octadecylamine (0.5 g) in n-pentane (50 mL). After impregnation for 10 minutes, the carbon cloth was removed, the liquid content was controlled at 90%, and it was dried at 80°C for 2 hours to obtain a fabric with a PDMS coating.

[0038] Using electron microscopy Figure 1 (a) and (d) it can be observed that in the presence of betaine, the zinc oxide generated in situ on the carbon fiber surface presents a uniform needle-like structure. These structures have a high aspect ratio and are regularly arranged on the carbon substrate. Their morphology is uniform and their size is regular, without agglomeration or twinning, indicating the excellent performance of betaine in buffering.

[0039] Figure 2 The X-ray photoelectron spectroscopy (XPS) of the zinc oxide coating on the carbon fiber surface prepared in Example 1 was tested. Figure 2b shows the XPS spectrum of Zn. The Zn 2p spectrum can be resolved to two significant peaks located at 1045.58 eV and 1022.43 eV, corresponding to the characteristic peaks of Zn 2p¹ / ² and Zn 2p³ / ², respectively. Figure 2 The c, O 1s energy spectrum can be decomposed into two peaks, with 531 eV and 529 eV corresponding to the zinc oxygen vacancy and the zinc oxygen bond near the oxygen bond, respectively.

[0040] Figure 3 XRD patterns of the zinc oxide coating on the carbon fiber surface prepared in Example 1 and the polysiloxane-treated zinc oxide carbon cloth were obtained by X-ray diffraction. The zinc oxide crystal form conforms to the hexagonal wurtzite structure, and typical wurtzite zinc oxide structures (JCPDS: 36-1451) appear at 31.84°, 34.52°, 36.32°, 47.6°, 56.64°, 62.92°, 66.36°, 67.96° and 69°, respectively, corresponding to its 100, 002, 101, 102, 110, 103, 200, 112 and 201 crystal planes. At the same time, a broad amorphous peak of carbon fiber appears at about 25.6°. Figure 3 b represents the Fourier transform infrared (FTIR) spectra of the zinc oxide coating on the carbon fiber surface and the polysiloxane-treated zinc oxide carbon cloth surface prepared in Example 1 of this invention. Compared with the original carbon cloth, the spectra at 600 cm⁻¹ are... - The ¹ position shows the zinc-oxygen bond stretching vibration of zinc oxide at 800 cm⁻¹. - ¹ A characteristic absorption peak of long-chain alkyl groups appeared near 1100 cm⁻¹ - The vibration at point ¹ is a silicon-oxygen stretching vibration, 1300 cm⁻¹. - The peak at ¹ represents the stretching vibration of silicon-carbon, and the peak at 3100 cm⁻¹ is also present. - Slight stretching vibrations of protonated ammonia were observed at position ¹. Furthermore, XRD analysis showed that the zinc oxide array carbon cloth coated with the silicon layer still maintained a good hexagonal zinc oxide zinc oxide structure, with clearly visible crystalline peaks at the corresponding scanning angles. Simultaneously, the broad amorphous peaks of the carbon cloth were also preserved, demonstrating that the silicon coating layer did not affect the overall structure of the material.

[0041] The elemental composition of the zinc oxide coating on the carbon fiber surface prepared in Example 1 after secondary modification with organosilicon was determined by EDS. (See attached image) Figure 4A layered organosilicon substance can be clearly seen covering the zinc oxide surface. Elemental scanning energy dispersive spectroscopy analysis detected silicon and nitrogen elements on the surface, further confirming the successful preparation of a hydrophobic coating layer formed by polydimethylsiloxane and octadecylamine. This coating not only provides hydrophobic properties but also enhances the stability of the material structure and improves adhesion during subsequent washing and rubbing processes.

[0042] Figure 5 This is a surface roughness test image of the carbon fiber prepared in Example 1. It clearly shows the difference in surface roughness between the carbon cloth after being processed with a zinc oxide array and subsequently modified with organosilicon. Figure 5 b), significantly higher than the original carbon cloth ( Figure 5 a) Roughness.

[0043] Surface performance testing.

[0044] Water contact angle test Figure 6 Figure 'a' shows the static contact angle test results of the carbon cloth before and after treatment in this embodiment. The original carbon cloth has certain hydrophobic properties, with a static contact angle of approximately 120°. After modification with the zinc oxide array, its surface exhibits extremely strong hydrophilicity, and water droplet tests show that the liquid can be rapidly absorbed and wetted. However, by further constructing a hydrophobic layer, its surface becomes extremely hydrophobic again, with a static contact angle of approximately 150°. This is mainly due to the synergistic effect of the zinc oxide nanoarray with the low surface energy coating materials of polydimethylsiloxane and stearic acid, producing a needle-like effect similar to that of a lotus leaf. The nano-zinc oxide array effectively encapsulates the air layer, and combined with the effect of the low surface energy materials, it achieves excellent hydrophobicity.

[0045] Soap washing test A standard soaping solution was prepared, with a soap concentration of 1 g / L and a sodium carbonate concentration of 2 g / L. The prepared carbon cloth was then immersed in the soaping solution, and the soaping conditions were set to 40°C for 30 minutes. After soaping, the material was rinsed and dried using standard methods. Next, a static water contact angle test was performed to observe whether the soaping process affected the hydrophobic properties of the material. Furthermore, using the same soaping formula and process conditions, the number of soaping cycles was increased, and the static water contact angle was tested after 2 and 5 soaping cycles, respectively.

[0046] from Figure 6The results show that, after one soaping test, although the static water contact angle of the treated carbon cloth decreased slightly, after five soaping tests, the water contact angle remained above 150° (150.5°). This result indicates that the hydrophobic properties of the material remain at a high level after soaping, demonstrating its excellent wash resistance and stable hydrophobic properties. This proves that the carbon cloth prepared in this embodiment not only maintains its original hydrophobic properties after soaping and cleaning tests, but also demonstrates its reliability and durability in actual use. This provides important experimental data and performance assurance for applications requiring high hydrophobic properties, such as waterproof fabrics and self-cleaning surfaces.

[0047] Friction test First, the carbon cloth is carefully placed on a flat piece of paper to ensure its stability. Then, a standard metal weight weighing 250 g is placed in the center of the carbon cloth, 10 cm away. Next, an abrasion resistance test is performed on the carbon cloth, during which it will experience varying degrees of frictional damage.

[0048] From the experimental results Figure 6 As can be clearly seen in Figure c, the carbon cloth still maintains high hydrophobicity after being rubbed with sandpaper, and its static contact angle with water does not decrease significantly. This indicates that the hydrophobic properties of the carbon cloth are relatively stable under low-frequency or mild friction conditions. This finding has important guiding significance for the durability and performance maintenance of carbon cloth in practical applications.

[0049] Anti-fouling performance test The anti-fouling performance of the carbon cloth treated in Example 1 was tested. Water, methylene blue aqueous solution, and dye yellow aqueous solution were prepared. Untreated carbon cloth and carbon cloth coated with zinc oxide and modified with PDMS were immersed in the solutions respectively for 1 minute, and then removed and the wetting condition of both was observed.

[0050] Test results of untreated carbon cloth as follows Figure 7 a. It can be seen that the untreated carbon cloth exhibited a certain degree of wetting after immersion in water, especially in solutions of methylene blue and dye yellow, where it was almost completely soaked, resulting in severe surface contamination and obvious adhesion of the dyes. In contrast, the carbon cloth treated with zinc oxide combined with PDMS showed no wetting or contamination after immersion in these three solutions, maintaining a clean and tidy surface throughout. This indicates that the zinc oxide carbon cloth with its hydrophobic layer structure possesses excellent anti-fouling properties against aqueous solutions, effectively resisting the adhesion of liquids and dyes, thus maintaining its cleanliness while extending its service life and functionality. This characteristic gives the carbon cloth significant advantages in various practical applications, particularly in environments requiring frequent contact with liquids or prone to contamination, where it provides excellent protection.

[0051] Surface self-cleaning test The surface self-cleaning test was conducted by comparing the original carbon cloth and the tested carbon cloth. Chalk dust was used as a simulated dust layer. Chalk dust was placed on the surface of both untreated carbon cloth and carbon cloth treated with zinc oxide combined with PDMS, and then rinsed with water to simulate the self-cleaning process of washing fabric surfaces in daily life. Figure 8 The difference between the two is clearly observable. Although the powder on the untreated carbon cloth was rinsed with water, water-soluble white marks remained on the surface. Even after multiple rinses, these white marks remained firmly attached to the fiber surface and were difficult to remove. Figure 8 (a, where a1, a2, and a3 are experimental steps). In contrast, the treated carbon cloth performed the opposite. With just a simple rinse of water, the powder on its surface was immediately removed from the fabric by the water flow, leaving no residue. The entire surface was restored to a clean and tidy state. Figure 8 (b, where b1, b2, and b3 are experimental steps). This comparison fully demonstrates that the tested carbon cloth has a significant advantage in terms of water washing self-cleaning ability. Its surface properties make it easier to remove dirt, maintain the cleanliness of the fabric, and provide great convenience and practicality for real-life applications.

[0052] Example 2 (1) Carbon cloth pretreatment is as described in Example 1; (2) In-situ reaction and post-treatment Weigh 0.6 g of zinc chloride and dissolve it in 20 mL of deionized water (zinc chloride concentration 30 g / L), then add 1 mL of ammonia water and 0.11 g of ammonium chloride to prepare a zinc ion precursor solution; The carbon cloth loaded with zinc oxide layer was immersed in zinc ion precursor solution with a bath ratio of 20, and then reacted at 100℃ for 2 hours. After the reaction was completed, it was naturally cooled to room temperature, then washed three times with water (50 mL), and finally placed in a drying oven and annealed at 60℃ for 2 hours to obtain a carbon cloth product with zinc oxide coating layer grown in situ on the fiber surface.

[0053] (3) Zinc oxide surface modification treatment is as described in Example 1.

[0054] Using electron microscopy Figure 1 (b) and (e) it can be observed that under ammonium chloride, zinc oxide exhibits a uniform lamellar structure.

[0055] Example 3 (1) Carbon cloth pretreatment is as described in Example 1; (2) In-situ reaction and post-treatment Weigh 0.6 g of zinc chloride and dissolve it in 20 mL of deionized water (zinc chloride concentration 30 g / L), then add 1 mL of ammonia and 0.27 g of ethylenediamine hydrochloride to prepare a zinc ion precursor solution; The carbon cloth loaded with zinc oxide layer was immersed in zinc ion precursor solution with a bath ratio of 20, and then reacted at 100℃ for 2 hours. After the reaction was completed, it was naturally cooled to room temperature, then washed with water three times (50 mL), and finally placed in a drying oven and annealed at 60℃ for 2 hours to obtain a carbon cloth product with zinc oxide coating layer grown in situ on the fiber surface (zinc oxide coated carbon cloth).

[0056] (3) Zinc oxide surface modification treatment is as described in Example 1.

[0057] Using electron microscopy Figure 1 (c and f) It can be observed that the morphology of zinc oxide is controllable under ethylenediamine hydrochloride, and a uniform granular structure is generated in situ on the inner surface of carbon fiber.

[0058] The products from Examples 1, 2, and 3 were tested, from... Figure 9 It is evident that the hydrophobic properties of the materials in Examples 1, 2, and 3 differ. Example 1 exhibits the best hydrophobicity at 154.3°, followed by Example 2 at 147.4°, while Example 3 shows the lowest at 143.2°. This indicates that the zinc oxide preparation process affects the hydrophobic properties of the materials. Comparatively, the product of Example 1 is more conducive to achieving superhydrophobicity (water contact angle > 150°).

[0059] Comparative Example 1 (1) Carbon cloth pretreatment is as described in Example 1; (2) Weigh 0.6 g of zinc chloride and dissolve it in 20 mL of deionized water (zinc chloride concentration 30 g / L), then add 1 mL of ammonia water to prepare zinc ion precursor solution; The carbon cloth loaded with zinc oxide layer was immersed in zinc ion precursor solution with a bath ratio of 20, and then reacted at 100℃ for 2 hours. After the reaction was completed, it was naturally cooled to room temperature, then washed three times with water (50 mL), and finally placed in a drying oven and annealed at 60℃ for 2 hours to obtain a carbon cloth product with zinc oxide coating layer grown in situ on the fiber surface.

[0060] (3) Zinc oxide surface modification treatment is as described in Example 1.

[0061] Depend on Figure 10 It can be seen that the water contact angle of the material is 131.7, which is not significantly improved compared to the original carbon cloth's 119.1.

[0062] Comparative Example 2 Weigh 0.6 g of zinc chloride and dissolve it in 20 mL of deionized water (zinc chloride concentration 30 g / L). Then add 1 mL of ammonia water (28 wt%) and 0.23 g of betaine to prepare a zinc ion precursor solution. The carbon cloth (without zinc oxide layer) was immersed in zinc ion precursor solution at a bath ratio of 20 and then reacted at 100℃ for 2 hours. After the reaction was completed, it was naturally cooled to room temperature and then washed three times with water (50 mL). Finally, it was placed in a drying oven and annealed at 60℃ for 2 hours to obtain a carbon cloth product with a zinc oxide coating layer grown in situ on the fiber surface (zinc oxide coated carbon cloth).

[0063] The zinc oxide surface modification treatment was carried out in accordance with Example 1, and a fabric with a PDMS coating was finally obtained.

[0064] Depend on Figure 10 It can be seen that the water contact angle of the material is 130.1, which is not significantly improved compared to the original carbon cloth's 119.1.

[0065] Comparative Example 3 (1) Carbon cloth pretreatment refers to Example 1 to obtain carbon cloth loaded with zinc oxide layer.

[0066] (2) The carbon cloth loaded with zinc oxide layer was directly modified with polysiloxane (PDMS) to cover the zinc oxide surface with a low surface energy material. The bath ratio was 50. The impregnation solution was prepared by dissolving PDMS (2 g) and octadecylamine (0.5 g) in n-pentane (50 mL). After the zinc oxide coated carbon cloth was impregnated for 10 minutes, the carbon cloth was taken out, the liquid content was controlled to be 90%, and it was dried at 80°C for 2 hours to finally obtain the fabric with PDMS coating.

[0067] Depend on Figure 10 It can be seen that the water contact angle of the material is 122.7, which is almost no improvement in hydrophobicity compared to the original carbon cloth's 119.1.

Claims

1. A method for preparing a stable superhydrophobic flexible material, characterized in that, Includes the following steps: (1) Immerse carbon fiber material in nano zinc oxide solution to obtain carbon fiber material loaded with nano zinc oxide; (2) The carbon fiber material loaded with nano zinc oxide is immersed in a zinc salt solution, then subjected to hydrothermal reaction, and then annealed to obtain the carbon fiber material loaded with zinc oxide coating. (3) Polysiloxane is modified on the surface of carbon fiber material loaded with zinc oxide coating to obtain a stable superhydrophobic flexible material.

2. The method for preparing the stable superhydrophobic flexible material according to claim 1, characterized in that, Carbon fiber material with zinc oxide coating was immersed in PDMS solution, and polysiloxane was modified on the surface of the carbon fiber material with zinc oxide coating to obtain a stable superhydrophobic flexible material.

3. A method for preparing a stable hydrophilic flexible material, characterized in that, Includes the following steps: (1) Immerse carbon fiber material in nano zinc oxide solution to obtain carbon fiber material loaded with nano zinc oxide; (2) The carbon fiber material loaded with nano zinc oxide is immersed in a zinc salt solution, then subjected to hydrothermal reaction, and then annealed to obtain a carbon fiber material loaded with zinc oxide coating, which is a stable hydrophilic flexible material.

4. The preparation method according to claim 1 or 3, characterized in that, The nano zinc oxide solution includes nano zinc oxide and a small molecule alcohol solvent; the concentration of nano zinc oxide in the nano zinc oxide solution is 1-10 mg / mL.

5. The preparation method according to claim 1 or 3, characterized in that, The zinc salt solution includes water-soluble zinc salt, ammonia, additives, and water. The additives include one or more of ethylenediamine hydrochloride, ammonium chloride, and betaine.

6. The preparation method according to claim 5, characterized in that, In the zinc salt solution, the concentration of zinc salt is 10-50 g / L, the volume ratio of ammonia to water is (0.5-1.5):20, and the concentration of additive is 0.05-0.2 mol / L.

7. The preparation method according to claim 1 or 3, characterized in that, The hydrothermal reaction temperature is 100℃±10℃, and the time is 90~150 minutes; the annealing temperature is 60℃±10℃, and the time is 100~150 minutes.

8. A stable superhydrophobic flexible material or a stable hydrophilic flexible material prepared by the preparation method according to claim 1 or 3.

9. The application of the stable superhydrophobic flexible material or the stable hydrophilic flexible material according to claim 8 in the preparation of hydrophobic products.

10. A hydrophobic product comprising the above-mentioned stable superhydrophobic flexible material.

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