A polyester cord coated with a polyurethane and rutin composite coating and a method for its preparation

Abstract

This invention discloses a polyester cable coated with a polyurethane and rutin composite coating and its preparation method. The method involves coating the surface of a polyester cable with a fluorinated polyurethane and rutin composite coating. The method involves reacting diisocyanate, polyol, and catalyst to obtain a prepolymer, then adding bisphenol AF, a small molecule chain extender, and tetrahydrofuran to obtain a fluorinated polyurethane solution. A rutin solution is prepared and mixed with the fluorinated polyurethane solution to obtain a fluorinated polyurethane and rutin composite material solution. The polyester cable is then immersed in the fluorinated polyurethane and rutin composite material solution, removed, air-dried, and oven-dried. This process is repeated several times to obtain the polyester cable coated with the polyurethane and rutin composite coating. The polyester cable of this invention has UV resistance, seawater corrosion resistance, and marine antifouling properties. The preparation method is simple, and it has broad application prospects in marine engineering, ship mooring, and marine fisheries.

Description

Technical Field

[0001] This invention relates to a polyester cable and its preparation method, and more particularly to a polyester cable coated with a polyurethane and rutin composite coating and its preparation method. Background Technology

[0002] Polyester ropes, due to their high strength, low elongation, and good flexibility, are widely used in marine engineering, ship mooring, and marine fisheries, and are an indispensable key material in marine operations. However, the marine environment is extremely complex and harsh. Polyester ropes exposed to the marine environment for extended periods are prone to multiple performance degradation issues, seriously affecting their service life and operational safety, becoming a core bottleneck restricting their further promotion and application in the marine field.

[0003] On the one hand, seawater contains a large amount of salt, microorganisms, and corrosive media. Long-term immersion can cause the surface of polyester cables to swell and degrade, leading to a decrease in mechanical properties and an increased risk of breakage. On the other hand, strong ultraviolet radiation in the marine environment can accelerate the aging and breakage of polyester molecular chains, causing the cable surface to yellow and become brittle, thus shortening its service life. In addition, the attachment of marine organisms (such as barnacles and algae) can cause surface contamination of the cable, increasing its weight and resistance, while also exacerbating corrosion and wear, further reducing its performance and durability.

[0004] To address the aforementioned issues, existing technologies often employ coatings to protect the surface of polyester cables. Polyurethane coatings, due to their excellent adhesion and flexibility, are a commonly used protective coating material. However, ordinary polyurethane coatings struggle to simultaneously meet the multiple protection requirements of UV resistance, seawater corrosion resistance, and marine fouling prevention. To optimize the protective performance of polyurethane coatings, existing technologies have explored introducing fluorine-containing monomers to modify the polyurethane, utilizing the low surface energy of fluorine to enhance the coating's antifouling and seawater corrosion resistance.

[0005] However, current technology cannot simultaneously meet the three core requirements of UV resistance, seawater corrosion resistance, and marine antifouling. Furthermore, existing coating preparation methods often suffer from complex processes, poor coating adhesion, and unstable protective effects, making it difficult to meet the stringent requirements of marine engineering for polyester cables.

[0006] Therefore, developing a polyester cable that can simultaneously achieve UV resistance, seawater corrosion resistance, and marine antifouling functions, with a simple preparation method, strong coating adhesion, and long-lasting and stable protective effect, is of great practical significance and application value for promoting the upgrading and optimization of marine engineering materials, extending the service life of polyester cables, and reducing the maintenance cost of marine operations. It is also a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] To overcome the problems existing in the background art, the present invention provides a polyester cable coated with a polyurethane and rutin composite coating and its preparation method. The preparation method of the present invention is simple, and the resulting polyester cable has good UV resistance, seawater corrosion resistance, and marine antifouling performance, and has broad application prospects in marine engineering, ship mooring, marine fisheries and other fields.

[0008] To achieve the above objectives, the present invention involves coating a polyester cable with a fluorinated polyurethane and rutin composite coating. The method involves reacting diisocyanate, polyol, and catalyst to obtain a prepolymer, then adding bisphenol AF, a small molecule chain extender, and tetrahydrofuran to obtain a fluorinated polyurethane solution. A rutin solution is prepared and mixed with the fluorinated polyurethane solution to obtain a fluorinated polyurethane and rutin composite solution. The polyester cable is then immersed in the fluorinated polyurethane and rutin composite solution, removed, air-dried, and oven-dried. This process is repeated several times to obtain a polyester cable coated with a polyurethane and rutin composite coating.

[0009] More specifically, the specific technical solution adopted by the present invention to solve its technical problem is as follows: 1. A polyester cable coated with a polyurethane and rutin composite coating: The surface of the polyester cable is coated with a composite coating of fluorinated polyurethane and rutin. The fluorinated polyurethane is mainly polymerized from diisocyanate, polyol, bisphenol AF and small molecule chain extender.

[0010] The molar ratio of the diisocyanate, polyol, bisphenol AF and small molecule chain extender is 14.7:4:2.5-7.5:7.5-2.5.

[0011] The diisocyanate is at least one of isophorone diisocyanate, hexamethylene diisocyanate, and cyclohexyl diisocyanate; The polyol is at least one of polypropylene glycol, polyoxypropylene polyol, and polytetrahydrofuran ether glycol; the small molecule chain extender is at least one of 1,4-butanediol, ethylene glycol, and hexanediol.

[0012] The content of rutin in the fluorinated polyurethane and rutin composite coating is 1-2 wt%, and the remaining components in the fluorinated polyurethane and rutin composite coating are all fluorinated polyurethane except for rutin.

[0013] II. A method for preparing a polyester cable coated with a polyurethane and rutin composite coating, the method comprising the following steps: Step 1) Under a nitrogen atmosphere, diisocyanate, polyol and catalyst are reacted at a certain temperature to obtain fluorinated polyurethane prepolymer; Step 2) Add bisphenol AF, a small molecule chain extender and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in Step 1), continue the reaction, and add tetrahydrofuran to dilute to obtain a fluorinated polyurethane solution. Step 3) Dissolve rutin in N,N-dimethylformamide to obtain a rutin solution; Step 4) Add the rutin solution obtained in Step 3) dropwise to the fluorinated polyurethane solution obtained in Step 2), and stir at a certain temperature until it is uniform and stable to obtain a fluorinated polyurethane and rutin composite material solution. Step 5) After fully immersing the polyester cable in the fluorinated polyurethane and rutin composite material solution obtained in Step 4), remove it, air dry it, and then dry it to constant weight. Step 6) Repeat step 5) several times to make the mass fraction of the fluorinated polyurethane and rutin composite coating in the polyester cable after coating 20wt%, and obtain the marine engineering polyester cable with the fluorinated polyurethane and rutin composite coating.

[0014] Step 1) specifically involves stirring diisocyanate, polyol, and catalyst at 65-85°C for 1-3 hours under a nitrogen atmosphere. The molar ratio of diisocyanate to polyol is 14.7:4, and the amount of catalyst used is 0.05% of the total mass of diisocyanate, polyol, bisphenol AF, and small molecule chain extender, to obtain a fluorinated polyurethane prepolymer.

[0015] The catalyst is at least one of dibutyltin dilaurate and stannous octoate.

[0016] Step 2) specifically involves adding bisphenol AF, a small molecule chain extender, and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in step 1) under a nitrogen atmosphere. The molar ratio of the fluorinated polyurethane prepolymer, bisphenol AF, and small molecule chain extender is 18.7:2.5-7.5:7.5-2.5. The amount of tetrahydrofuran used is 1.5 times the total mass of the reaction raw materials. The reaction is continued to be stirred at 65-85℃ for 1-3 hours. Tetrahydrofuran is then added to dilute the solid content of the fluorinated polyurethane to 20-40% by mass, resulting in a fluorinated polyurethane solution.

[0017] Step 4) specifically involves adding the rutin solution obtained in step 3) dropwise to the fluorinated polyurethane solution obtained in step 2), such that the proportion of rutin in the rutin solution to the total mass of the fluorinated polyurethane and rutin in the rutin solution is 1-2 wt%, and stirring at 65-85℃ for 10-30 min until uniform and stable, to obtain a fluorinated polyurethane and rutin composite material solution.

[0018] Step 5) specifically involves fully immersing the polyester cable in the fluorinated polyurethane and rutin composite material solution obtained in step 4), removing the polyester cable, air-drying it naturally for 24-48 hours, and then transferring it to a 60-80℃ oven to dry to a constant weight.

[0019] The polyester cable is used in marine engineering.

[0020] The beneficial effects of this invention are: This invention achieves a synergistic improvement in three core protective functions—UV resistance, seawater corrosion resistance, and marine antifouling—by coating the surface of polyester cables with a composite coating of fluorinated polyurethane and rutin. This effectively solves the problems of existing polyester cables being prone to aging, corrosion, and fouling in marine environments, making it suitable for demanding applications such as marine engineering, ship mooring, and marine fisheries. In the composite coating, the fluorinated polyurethane, leveraging the low surface energy of fluorine, effectively enhances the coating's resistance to seawater corrosion and marine antifouling, resisting the erosion of seawater salinity and corrosive media, and reducing marine organism adhesion. Rutin, as a natural antioxidant, efficiently absorbs ultraviolet light, inhibiting the aging and breakage of polyester molecular chains, while also contributing to improved antifouling performance. The synergistic effect of these two components makes the coating's protective effect more comprehensive and longer-lasting.

[0021] The preparation method of this invention is simple and easy to implement, requiring no complex production equipment or harsh reaction conditions. It can produce polyester cables coated with a fluorinated polyurethane and rutin composite coating, offering convenient operation, low production costs, and easy large-scale production and application. During the preparation process, the rutin solution and the fluorinated polyurethane solution exhibit good compatibility, resulting in a uniform and stable composite solution. When coated on the surface of the polyester cable, this solution forms a strong, dense composite coating that is resistant to peeling and cracking, providing stable protection and maintaining excellent performance in harsh marine environments for extended periods. The raw materials used in this invention are readily available, and the preparation process is green and environmentally friendly, generating no harmful pollutants. This ensures product safety, meets environmental protection requirements, and expands the application scope of polyester cables in marine engineering, possessing significant practical value and broad market prospects. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to specific embodiments.

[0023] The embodiments of the present invention are as follows: In the following examples, isophorone diisocyanate (99%), polytetrahydrofuran ether diol (AR), bisphenol AF (98%), rutin (95%), 1,4-butanediol (98%), and dibutyltin dilaurate (95%) were commercially available materials.

[0024] UV resistance test method: The transmittance of the fluorinated polyurethane and rutin composite coating in the range of 200-800 nm was tested using a Hitachi UH 4150 UV-Vis-NIR spectrophotometer.

[0025] Seawater erosion resistance test method: Before testing, the sample was placed in a 50 ºC forced-air drying oven for 24 hours to remove any residual moisture, and its initial dry weight (W0) was recorded. The dried sample was then completely immersed in artificial seawater and stored under constant temperature conditions to simulate a long-term seawater service environment. Every 30 days, the sample was removed, the surface moisture was blotted dry with filter paper, and the wet weight (W0) was measured. t The water absorption rate was calculated based on the changes in wet and dry weight over different immersion periods to evaluate the samples' resistance to seawater erosion in a long-term seawater environment. The formula for calculating the water absorption rate is: Water absorption rate = ((W) t -W0) / W0)×100% In the formula, W t : Wet weight, g; W0: Dry weight, g.

[0026] Marine antifouling performance testing method: *Nyctaginosa* was used in an anti-diatom test to simulate marine antifouling performance. Sodium metasilicate (7.3 mg / L) was added to artificial seawater as a silicon source for diatom growth. Sterilized seawater and algae were mixed at a volume ratio of 3:1 and cultured in a 25°C constant temperature and humidity incubator for 48 hours under 12h / 12h light-dark cycles. Subsequently, the samples were immersed in an algal suspension culture at 25°C for 7 days. After immersion, the samples were gently rinsed with artificial seawater to remove any unattached algae, and the algal coverage on the sample surface was observed using a laser confocal scanning electron microscope.

[0027] Coating adhesion test: The cross-cut adhesion test was conducted in accordance with ISO 2409:2020 standard.

[0028] Example 1: (1) 32.7g of isophorone diisocyanate, 40g of polytetrahydrofuran ether diol and dibutyltin dilaurate (catalyst) were added to a four-necked flask equipped with mechanical stirring, nitrogen protection and reflux condenser, and reacted at 80 °C for 2h to obtain fluorinated polyurethane prepolymer. (2) Add 25.2g of bisphenol AF, 2.3g of 1,4-butanediol and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in step 1), and continue stirring the reaction at 80°C for 2h. Add tetrahydrofuran to dilute the solid content of the fluorinated polyurethane to 30% to obtain a fluorinated polyurethane solution.

[0029] (3) Dissolve 2g of rutin in 100mL of N,N-dimethylformamide to obtain a rutin solution; (4) Slowly add 15 mL of the rutin solution obtained in step 3) to 100 mL of the fluorinated polyurethane solution obtained in step 2), and stir at 80 °C for 30 min until uniform and stable to obtain a fluorinated polyurethane and rutin composite material solution.

[0030] (5) Immerse the polyester cable in the fluorinated polyurethane and rutin composite material solution obtained in step 4), take out the polyester cable, air dry it naturally for 24 hours, and then transfer it to a 60°C oven to dry to constant weight. (6) Repeat step 5) several times to make the mass fraction of the fluorinated polyurethane and rutin composite coating in the polyester cable after coating 20wt%, and obtain the marine engineering polyester cable with the fluorinated polyurethane and rutin composite coating.

[0031] UV resistance test results: transmittance at 300nm is 0.19%; seawater corrosion resistance test results: water absorption rate is 10.5% after immersion in artificial seawater for 30 days; marine antifouling performance test results: diatom adhesion rate is 0.16%; coating adhesion test results: grade 0.

[0032] Example 2: (1) 32.7g of isophorone diisocyanate, 40g of polytetrahydrofuran ether diol and dibutyltin dilaurate (catalyst) were added to a four-necked flask equipped with mechanical stirring, nitrogen protection and reflux condenser, and reacted at 80 °C for 2h to obtain fluorinated polyurethane prepolymer. (2) Add 25.2g of bisphenol AF, 2.3g of 1,4-butanediol and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in step 1), and continue stirring the reaction at 80°C for 2h. Add tetrahydrofuran to dilute the solid content of the fluorinated polyurethane to 30% to obtain a fluorinated polyurethane solution.

[0033] (3) Dissolve 2g of rutin in 100mL of N,N-dimethylformamide to obtain a rutin solution; (4) Slowly add 22.5 mL of the rutin solution obtained in step 3) to 100 mL of the fluorinated polyurethane solution obtained in step 2), and stir at 80 °C for 30 min until uniform and stable to obtain a fluorinated polyurethane and rutin composite material solution.

[0034] (5) Immerse the polyester cable in the fluorinated polyurethane and rutin composite material solution obtained in step 4), take out the polyester cable, air dry it naturally for 24 hours, and then transfer it to a 60°C oven to dry to constant weight. (6) Repeat step 5) several times to make the mass fraction of the fluorinated polyurethane and rutin composite coating in the polyester cable after coating 20wt%, and obtain the marine engineering polyester cable with the fluorinated polyurethane and rutin composite coating.

[0035] UV resistance test results: transmittance at 300nm is 0.16%; seawater corrosion resistance test results: water absorption rate is 11.0% after immersion in artificial seawater for 30 days; marine antifouling performance test results: diatom adhesion rate is 0.17%; coating adhesion test results: grade 0.

[0036] Example 3: (1) 32.7g of isophorone diisocyanate, 40g of polytetrahydrofuran ether diol and dibutyltin dilaurate (catalyst) were added to a four-necked flask equipped with mechanical stirring, nitrogen protection and reflux condenser, and reacted at 80 °C for 2h to obtain fluorinated polyurethane prepolymer. (2) Add 25.2g of bisphenol AF, 2.3g of 1,4-butanediol and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in step 1), and continue stirring the reaction at 80°C for 2h. Add tetrahydrofuran to dilute the solid content of the fluorinated polyurethane to 30% to obtain a fluorinated polyurethane solution.

[0037] (3) Dissolve 2g of rutin in 100mL of N,N-dimethylformamide to obtain a rutin solution; (4) Slowly add 30 mL of the rutin solution obtained in step 3) to 100 mL of the fluorinated polyurethane solution obtained in step 2), and stir at 80 °C for 30 min until uniform and stable to obtain a fluorinated polyurethane and rutin composite material solution.

[0038] (5) Immerse the polyester cable in the fluorinated polyurethane and rutin composite material solution obtained in step 4), take out the polyester cable, air dry it naturally for 24 hours, and then transfer it to a 60°C oven to dry to constant weight. (6) Repeat step 5) several times to make the mass fraction of the fluorinated polyurethane and rutin composite coating in the polyester cable after coating 20wt%, and obtain the marine engineering polyester cable with the fluorinated polyurethane and rutin composite coating.

[0039] UV resistance test results: transmittance at 300nm is 0.15%; seawater corrosion resistance test results: water absorption rate is 11.1% after immersion in artificial seawater for 30 days; marine antifouling performance test results: diatom adhesion rate is 0.17%; coating adhesion test results: grade 0.

[0040] Comparative Example 1: Plain polyester cable without any coating or modification.

[0041] UV resistance test results: No coating, not applicable; Seawater corrosion resistance test results: Water absorption rate of 46.9% after immersion in artificial seawater for 10 minutes; Marine antifouling performance test results: Diatom adhesion rate of 1.91%; Coating adhesion test results: No coating, not applicable.

[0042] Comparative Example 2: (1) 32.7g of isophorone diisocyanate, 40g of polytetrahydrofuran ether diol and dibutyltin dilaurate (catalyst) were added to a four-necked flask equipped with mechanical stirring, nitrogen protection and reflux condenser, and reacted at 80 °C for 2h to obtain polyurethane prepolymer. (2) Add 9.0 g of 1,4-butanediol and tetrahydrofuran to the polyurethane prepolymer obtained in step 1), and continue stirring the reaction at 80°C for 2 h. Add tetrahydrofuran to dilute the solid content of the polyurethane to 30% to obtain a polyurethane solution.

[0043] (3) Soak the polyester cable in the polyurethane solution obtained in step 2) thoroughly, take out the polyester cable, air dry it naturally for 24 hours, and then put it into a 60℃ oven to dry to constant weight. (4) Repeat step 3) several times to make the mass fraction of polyurethane coating in the polyester cable after coating 20wt%, and obtain the polyester cable for marine engineering with polyurethane coating.

[0044] UV resistance test results: transmittance at 300nm is 56.7%; seawater corrosion resistance test results: water absorption rate is 24.8% after immersion in artificial seawater for 30 days; marine antifouling performance test results: diatom adhesion rate is 0.95%; coating adhesion test results: grade 0.

[0045] Comparative Example 3: (1) 32.7g of isophorone diisocyanate, 40g of polytetrahydrofuran ether diol and dibutyltin dilaurate (catalyst) were added to a four-necked flask equipped with mechanical stirring, nitrogen protection and reflux condenser, and reacted at 80 °C for 2h to obtain fluorinated polyurethane prepolymer. (2) Add 8.4 g of bisphenol AF, 6.8 g of 1,4-butanediol and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in step 1), and continue stirring the reaction at 80 °C for 2 h. Add tetrahydrofuran to dilute the solid content of the fluorinated polyurethane to 30% to obtain a fluorinated polyurethane solution.

[0046] (3) Immerse the polyester cable in the fluorinated polyurethane solution obtained in step 2), take out the polyester cable, air dry it naturally for 24 hours, and then put it into a 60℃ oven to dry to constant weight. (4) Repeat step 3) several times to make the mass fraction of the fluorinated polyurethane coating in the polyester cable after coating 20wt%, and obtain the marine engineering polyester cable with the fluorinated polyurethane coating.

[0047] UV resistance test results: transmittance at 300nm is 51.8%; seawater corrosion resistance test results: water absorption rate is 16.7% after immersion in artificial seawater for 30 days; marine antifouling performance test results: diatom adhesion rate is 0.65%; coating adhesion test results: grade 0.

[0048] Comparative Example 4: (1) 32.7g of isophorone diisocyanate, 40g of polytetrahydrofuran ether diol and dibutyltin dilaurate (catalyst) were added to a four-necked flask equipped with mechanical stirring, nitrogen protection and reflux condenser, and reacted at 80 °C for 2h to obtain fluorinated polyurethane prepolymer. (2) Add 25.2g of bisphenol AF, 2.3g of 1,4-butanediol and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in step 1), and continue stirring the reaction at 80°C for 2h. Add tetrahydrofuran to dilute the solid content of the fluorinated polyurethane to 30% to obtain a fluorinated polyurethane solution.

[0049] (3) Immerse the polyester cable in the fluorinated polyurethane solution obtained in step 2), take out the polyester cable, air dry it naturally for 24 hours, and then put it into a 60℃ oven to dry to constant weight. (4) Repeat step 3) several times to make the mass fraction of the fluorinated polyurethane coating in the polyester cable after coating 20wt%, and obtain the marine engineering polyester cable with the fluorinated polyurethane coating.

[0050] UV resistance test results: transmittance at 300nm is 22.3%; seawater corrosion resistance test results: water absorption rate is 10.7% after immersion in artificial seawater for 30 days; marine antifouling performance test results: diatom adhesion rate is 0.18%; coating adhesion test results: grade 0.

[0051] Comparative Example 5: (1) 32.7g of isophorone diisocyanate, 40g of polytetrahydrofuran ether diol and dibutyltin dilaurate (catalyst) were added to a four-necked flask equipped with mechanical stirring, nitrogen protection and reflux condenser, and reacted at 80 °C for 2h to obtain fluorinated polyurethane prepolymer. (2) Add 25.2g of bisphenol AF, 2.3g of 1,4-butanediol and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in step 1), and continue stirring the reaction at 80°C for 2h. Add tetrahydrofuran to dilute the solid content of the fluorinated polyurethane to 30% to obtain a fluorinated polyurethane solution.

[0052] (3) Dissolve 2g of rutin in 100mL of N,N-dimethylformamide to obtain a rutin solution; (4) Slowly add 75 mL of the rutin solution obtained in step 3) to 50 mL of the fluorinated polyurethane solution obtained in step 2), and stir at 80 °C for 30 min until uniform and stable to obtain a fluorinated polyurethane and rutin composite material solution.

[0053] (5) Immerse the polyester cable in the fluorinated polyurethane and rutin composite material solution obtained in step 4), take out the polyester cable, air dry it naturally for 24 hours, and then transfer it to a 60°C oven to dry to constant weight. (6) Repeat step 5) several times to make the mass fraction of the fluorinated polyurethane and rutin composite coating in the polyester cable after coating 20wt%, and obtain the marine engineering polyester cable with the fluorinated polyurethane and rutin composite coating.

[0054] Coating adhesion test result: Level 2.

[0055] The test data above show that the polyester cables of Examples 1-3 of the present invention have significantly better resistance to ultraviolet radiation, seawater corrosion, and marine antifouling than those of Comparative Examples 1-5. Compared with Comparative Example 1, Comparative Example 2 showed a significant decrease in both water absorption and diatom adhesion rate, indicating that the polyurethane coating can effectively improve the resistance to seawater erosion and marine antifouling performance.

[0056] Compared with Comparative Example 2, Comparative Examples 3 and 4 showed a significant decrease in transmittance at 300 nm, as well as a significant decrease in water absorption and diatom adhesion rate. This indicates that polyurethane containing bisphenol AF can effectively improve UV resistance, and fluorinated polyurethane can further improve seawater erosion resistance and marine antifouling performance.

[0057] Compared with Comparative Examples 3 and 4, the transmittance of Examples 1-3 at 300 nm decreased significantly, indicating that rutin can effectively enhance the UV aging resistance of the composite coating. Moreover, the adhesion of Examples 1-3 remained at grade 0, which was better than that of Comparative Example 5, indicating that the amount of rutin added needs to be controlled within a reasonable range to ensure the adhesion between the coating and the cable substrate and to prevent the coating from falling off.

[0058] In summary, this invention, through the synergistic effect of fluorinated polyurethane and rutin, combined with an optimized preparation process, enables polyester cables to simultaneously possess excellent UV resistance, seawater corrosion resistance, and marine antifouling properties, while also exhibiting strong coating adhesion, meeting the requirements for use in the marine engineering field.

[0059] The above embodiments are used to explain and illustrate the present invention, but not to limit the present invention. Any modifications and changes made to the present invention within the spirit and scope of the claims shall be applicable to the scope of protection of the present invention.

Claims

1. A polyester cable coated with a polyurethane and rutin composite coating, characterized in that: The surface of the polyester cable is coated with a composite coating of fluorinated polyurethane and rutin. The fluorinated polyurethane is mainly polymerized from diisocyanate, polyol, bisphenol AF and small molecule chain extender.

2. The polyester cable with a polyurethane and rutin composite coating according to claim 1, characterized in that: The molar ratio of the diisocyanate, polyol, bisphenol AF and small molecule chain extender is 14.7:4:2.5-7.5:7.5-2.

5.

3. The polyester cable with a polyurethane and rutin composite coating according to claim 1, characterized in that: The diisocyanate is at least one of isophorone diisocyanate, hexamethylene diisocyanate, and cyclohexyl diisocyanate; The polyol is at least one of polypropylene glycol, polyoxypropylene polyol, and polytetrahydrofuran ether glycol; the small molecule chain extender is at least one of 1,4-butanediol, ethylene glycol, and hexanediol.

4. The polyester cable with a polyurethane and rutin composite coating according to claim 1, characterized in that: The content of rutin in the fluorinated polyurethane and rutin composite coating is 1-2 wt%.

5. A method for preparing a polyester cable coated with a polyurethane and rutin composite coating as described in any one of claims 1-4, characterized in that, The method includes the following steps: Step 1) Under a nitrogen atmosphere, diisocyanate, polyol and catalyst are reacted at a certain temperature to obtain fluorinated polyurethane prepolymer; Step 2) Add bisphenol AF, a small molecule chain extender and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in Step 1), continue the reaction, and add tetrahydrofuran to dilute to obtain a fluorinated polyurethane solution. Step 3) Dissolve rutin in N,N-dimethylformamide to obtain a rutin solution; Step 4) Add the rutin solution obtained in Step 3) dropwise to the fluorinated polyurethane solution obtained in Step 2), and stir at a certain temperature until it is uniform and stable to obtain a fluorinated polyurethane and rutin composite material solution. Step 5) After fully immersing the polyester cable in the fluorinated polyurethane and rutin composite material solution obtained in Step 4), remove it, air dry it, and then dry it to constant weight. Step 6) Repeat step 5) several times to obtain the polyester cable with the fluorinated polyurethane and rutin composite coating.

6. The method for preparing a polyester cable coated with a polyurethane and rutin composite coating according to claim 5, characterized in that: Step 1) specifically involves stirring diisocyanate, polyol, and catalyst at 65-85°C for 1-3 hours under a nitrogen atmosphere. The molar ratio of diisocyanate to polyol is 14.7:4, and the amount of catalyst used is 0.05% of the total mass of diisocyanate, polyol, bisphenol AF, and small molecule chain extender, to obtain a fluorinated polyurethane prepolymer.

7. The method for preparing a polyester cable coated with a polyurethane and rutin composite coating according to claim 5, characterized in that: Step 2) specifically involves adding bisphenol AF, a small molecule chain extender, and tetrahydrofuran to the fluorinated polyurethane prepolymer obtained in step 1) under a nitrogen atmosphere. The molar ratio of the fluorinated polyurethane prepolymer, bisphenol AF, and the small molecule chain extender is 18.7:2.5-7.5:7.5-2.

5. The reaction is continued to be stirred at 65-85°C for 1-3 hours. Tetrahydrofuran is then added to dilute the solid content of the fluorinated polyurethane to 20-40%, resulting in a fluorinated polyurethane solution.

8. The method for preparing a polyester cable coated with a polyurethane and rutin composite coating according to claim 5, characterized in that: Step 4) specifically involves adding the rutin solution obtained in step 3) dropwise to the fluorinated polyurethane solution obtained in step 2), such that the proportion of rutin in the rutin solution to the total mass of the fluorinated polyurethane and rutin in the rutin solution is 1-2 wt%, and stirring at 65-85℃ for 10-30 min until uniform and stable, to obtain a fluorinated polyurethane and rutin composite material solution.

9. A method for preparing a polyester cable coated with a polyurethane and rutin composite coating according to claim 5, characterized in that: Step 5) specifically involves fully immersing the polyester cable in the fluorinated polyurethane and rutin composite material solution obtained in step 4), removing the polyester cable, air-drying it naturally for 24-48 hours, and then transferring it to a 60-80℃ oven to dry to a constant weight.

10. The application of the polyester cable according to any one of claims 1-4 or the polyester cable made by any one of claims 5-9, characterized in that: Applications in marine engineering.