A multifunctional composite material for offshore wind turbine towers that combines wave absorption, electrothermal properties, corrosion resistance, and UV protection.

Abstract

This invention discloses a method for preparing a multifunctional graphite / iron powder / geotextile composite material, relating to multifunctional material technology. The preparation method includes the following steps: First, PU-2540 resin is stirred at 500 rpm for 10 minutes. Then, graphite, iron powder, and dispersant are added at 600 rpm over 4 hours. After the addition is complete, the stirring speed is increased to 800 rpm, and dispersion continues for 30 minutes. The prepared slurry is scraped onto geotextile, and then placed on a polytetrafluoroethylene film and allowed to stand at room temperature for 16 hours. After standing, the material is clamped on both sides into a stainless steel hot press mold and placed in the center of the lower platen of the hot press. The hot press is started, a certain pressure is applied and maintained constant, and then the upper and lower plates are heated simultaneously, and hot pressing is performed under this pressure and temperature. This invention achieves multifunctional integration of wave absorption, electrothermal properties, corrosion resistance, and UV protection, providing a lightweight and flexible integrated protective material solution for offshore wind turbine towers.

Description

Technical Field

[0001] This invention belongs to the field of multifunctional materials technology, specifically relating to a method for preparing a multifunctional graphite / iron powder / geotextile composite material that integrates wave absorption, electrothermal properties, corrosion resistance, and UV protection. Background Technology

[0002] As the global energy structure shifts towards clean and renewable energy, offshore wind power, with its advantages of stable resources, high power generation efficiency, and no reliance on land resources, has become a core direction for the large-scale development of new energy. As a key supporting structure for the turbine, the offshore wind turbine tower operates for extended periods in the harsh marine environment characterized by high salt spray, strong ultraviolet radiation, wave impact, and extreme temperature differences. Its surface protective materials directly determine the turbine's service life and operational reliability. However, current wind turbine tower protective materials often focus on single protective functions, such as corrosion resistance or UV protection, which are insufficient to meet the multifunctional requirements of modern offshore wind turbine towers in harsh marine environments. For example, the massive metal tower body strongly reflects radar signals, potentially causing electromagnetic interference to aviation navigation and maritime monitoring. Simultaneously, the tower surface is prone to icing in low-temperature environments, affecting operational safety and power generation efficiency. Furthermore, wave erosion, saltwater corrosion, and ultraviolet aging also seriously threaten the long-term service life of the tower.

[0003] Geotextiles possess excellent mechanical properties, acid and alkali resistance, low cost, and flexibility, making them widely used in engineering protection. However, they lack inherent wave absorption, electrothermal conversion, and UV protection functions, rendering them unsuitable for direct use in offshore wind turbine tower protection. While some research has attempted to improve the performance of traditional materials like geotextiles in specific engineering scenarios through functional modification, existing materials still struggle to simultaneously meet the multiple performance requirements of electromagnetic wave absorption, electrothermal conversion, corrosion resistance, and UV protection in the extreme service environment of offshore wind turbine towers. Therefore, developing a novel composite material integrating multiple functions is of significant scientific and engineering importance for improving the overall performance and service reliability of offshore wind power equipment.

[0004] Against this backdrop, this invention proposes a method for preparing a multifunctional graphite / iron powder / geotextile composite material for offshore wind turbine towers. The aim is to achieve integrated functionality such as wave absorption, electrothermal properties, corrosion resistance, and UV protection through a functional particle composite modification strategy, providing new ideas and methods for the design of multifunctional protective materials for offshore wind turbine towers. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for preparing a graphite / iron powder / geotextile composite material. This method uses a coating and hot-pressing process to synergistically introduce graphite and iron powder into the geotextile, achieving integrated multi-functional properties such as wave absorption, electrothermal properties, corrosion resistance, and UV protection.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] The preparation method of graphite / iron powder / geotextile composite material includes the following steps:

[0008] S1. Preparation of base fabric: Cut the polyethylene short fiber geotextile into 12cm×12cm pieces.

[0009] S2. Slurry Preparation: First, stir 100g of PU-2540 resin at 500rpm for 10min. Then, add functional particles and additives stepwise over 4h at 600rpm: (a) slowly add half a part of graphite, (b) add HTK-5040 dispersant and stir for 10min, (c) add iron powder at a uniform rate, and (d) slowly add the remaining graphite. Finally, increase the speed to 800rpm and disperse at high speed for 30min.

[0010] S3. Preparation of Composite Material: The prepared slurry was coated onto both sides of a polyethylene short-fiber geotextile. The coated fabric was then placed on a polytetrafluoroethylene film and allowed to stand at room temperature for 16 hours. After standing, the fabric was clamped into a stainless steel hot press mold and placed in the center of the lower platen of the hot press. Finally, the hot press was started: (a) a certain pressure was slowly applied to the upper and lower plates and then kept constant; (b) the upper and lower plates were heated to a certain temperature simultaneously; (c) the pressure and temperature were kept constant and hot-pressed for 60–120 minutes; (d) the sample was removed after the time was up.

[0011] Preferably, the total amount of graphite and iron powder added in S2 is 45 wt% (relative to PU-2540 resin), the mass ratio of graphite to iron powder is 3:1, and the amount of HTK-5040 dispersant added is 2 wt% (relative to PU-2540 resin).

[0012] Preferably, the pressure of the hot press in S3 is 0.6 to 1.5 t, and the temperature is 60 to 100 ℃.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] For the first time, a graphite / iron powder composite system is combined with geotextile. Through hot pressing, functional particles are firmly attached to the fiber surface and a conductive network is uniformly constructed. Through optimized design of functional particle ratio and process parameters, multiple functions such as wave absorption, electrothermal properties, UV protection, and corrosion resistance are integrated. The preparation process is simple, low-cost, and environmentally friendly, making it suitable for large-scale industrial production. It provides a lightweight and flexible integrated protective material solution for offshore wind turbine towers. Attached Figure Description

[0015] Figure 1This is a flowchart illustrating the preparation process of the graphite / iron powder / geotextile composite material in this invention.

[0016] Figure 2 The images are SEM images of the graphite / iron powder / geotextile composite material in this invention at different magnifications.

[0017] Figure 3 The graph shows the dielectric properties of the graphite / iron powder / geotextile composite material in this invention and after chemical corrosion, where a is the real part of the dielectric constant, b is the imaginary part of the dielectric constant, and c is the loss tangent.

[0018] Figure 4 This is a diagram showing the reflection loss of the graphite / iron powder / geotextile composite material in this invention after chemical corrosion.

[0019] Figure 5 The images show the graphite / iron powder / geotextile composite material and its electrothermal image after chemical corrosion in this invention. In the images, a and c are the temperature rise curve and three-dimensional imaging image of the graphite / iron powder / geotextile composite material under a voltage of 9-12V, respectively, and b and d are the temperature rise curve and three-dimensional imaging image of the graphite / iron powder / geotextile composite material after chemical corrosion under a voltage of 9V, respectively.

[0020] Figure 6 This is a diagram showing the UV protection performance of the graphite / iron powder / geotextile composite material in this invention after chemical corrosion.

[0021] Figure 7 This is a diagram showing the electrical conductivity of the graphite / iron powder / geotextile composite material in this invention after chemical corrosion.

[0022] Figure 8 This is a graph showing the mass loss of the graphite / iron powder / geotextile composite material under different friction cycles in this invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1:

[0025] The preparation method of graphite / iron powder / geotextile composite material includes the following steps:

[0026] Step 1: Cut the polyethylene short-fiber geotextile into 12cm x 12cm pieces.

[0027] Step 2: First, stir 100g of PU-2540 resin at 500rpm for 10min. Then, over 4 hours, add 45wt% functional particles and 2wt% dispersant (relative to PU-2540 resin) in steps at 600rpm: (a) slowly add half a part of graphite, (b) add HTK-5040 dispersant and stir for 10min, (c) add iron powder at a uniform rate, and (d) slowly add the remaining graphite. Finally, increase the speed to 800rpm and disperse at high speed for 30min.

[0028] Step 3: Apply the prepared slurry to both sides of the polyethylene short-fiber geotextile, then place the coated fabric on a polytetrafluoroethylene film and let it stand at room temperature for 16 hours. After standing, clamp both sides of the fabric into a stainless steel hot press mold and place it in the center of the lower platen of the hot press. Finally, start the hot press: (a) slowly apply a certain pressure to the upper and lower plates and then keep it constant; (b) simultaneously raise the temperature of the upper and lower plates to 80°C; (c) keep the pressure and temperature constant and hot press for 90 minutes; (d) remove the sample after the timer expires.

[0029] Corrosion resistance testing: The graphite / iron powder / geotextile composite material prepared in Example 1 was immersed in 0.01 mol / L HCl solution, 0.1 mol / L NaOH solution, and 3.5 wt% NaCl solution, respectively, for 120 h. After immersion, it was rinsed with water and dried, and its dielectric, microwave absorption, electrothermal, electrical conductivity, and UV protection properties were tested.

[0030] The above description is merely a preferred embodiment of the present invention and is only used to help understand the method and core essence of the present invention. However, the scope of protection of the present invention is not limited thereto. For those skilled in the art, within the technical scope disclosed in the present invention, any equivalent substitutions or modifications made according to the technical solution and inventive concept of the present invention should be covered within the scope of protection of the present invention. In summary, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for preparing a graphite / iron powder / geotextile composite material, characterized in that, Includes the following steps: S1. Preparation of base fabric: Cut the polyethylene short fiber geotextile into 12cm×12cm pieces. S2. Slurry Preparation: First, stir 100g of PU-2540 resin at 500rpm for 10min. Then, add functional particles and additives stepwise over 4h at 600rpm: (a) slowly add half a part of graphite, (b) add HTK-5040 dispersant and stir for 10min, (c) add iron powder at a uniform rate, and (d) slowly add the remaining graphite. Finally, increase the speed to 800rpm and disperse at high speed for 30min. S3. Preparation of Composite Material: The prepared slurry was coated onto both sides of a polyethylene short-fiber geotextile. The coated fabric was then placed on a polytetrafluoroethylene film and allowed to stand at room temperature for 16 hours. After standing, the fabric was clamped into a stainless steel hot press mold and placed in the center of the lower platen of the hot press. Finally, the hot press was started: (a) a certain pressure was slowly applied to the upper and lower plates and then kept constant; (b) the upper and lower plates were heated to a certain temperature simultaneously; (c) the pressure and temperature were kept constant and hot-pressed for 60–120 minutes; (d) the sample was removed after the time was up.

2. The method for preparing the graphite / iron powder / geotextile composite material according to claim 1, characterized in that, The total amount of graphite and iron powder added in S2 is 45 wt% (relative to PU-2540 resin), the mass ratio of graphite to iron powder is 3:1, and the amount of HTK-5040 dispersant added is 2 wt% (relative to PU-2540 resin).

3. The method for preparing the graphite / iron powder / geotextile composite material according to claim 1, characterized in that, The pressure of the hot press in S3 is 0.6 to 1.5 t, and the temperature is 60 to 100 ℃.

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