A highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film and its preparation method

Abstract

This invention discloses a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film and its preparation method, comprising the following components by mass percentage: 65.5%–70.5% ethylene-tetrafluoroethylene copolymer, 1.0%–2% ultraviolet absorber, 1.0%–2% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 10–14% titanium dioxide, and 1.0%–2.0% hydrophobic agent. The fluorohydrophobic agent of this invention has high heat resistance, weather resistance, and chemical inertness; it can form a dense fluorocarbon layer, making the surface extremely hydrophobic, reducing the surface energy of the material, increasing the contact angle, and reducing the roll-off angle. The ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, toughening agent, nucleating agent, and hydrophobic material are co-extruded, cast, and stretched into a film to obtain the high weather-resistant hydrophobic polyethylene tetrafluoroethylene film.

Description

Technical Field

[0001] This invention relates to the field of thin films, specifically to a highly weather-resistant hydrophobic polyethylene tetrafluoroethylene thin film and its preparation method. Background Technology

[0002] Currently, 5G mobile communication technology has become a crucial infrastructure supporting society's transformation towards digitalization, networking, and intelligence. The development of 5G technology relies heavily on a large number of 5G base stations. Statistics from the Ministry of Industry and Information Technology show that by the end of 2022, China had built 2.3 million 5G base stations. 5G radomes are an important component of 5G base stations, responsible for protecting the antenna system from interference from complex outdoor environments, improving antenna accuracy and reliability, and extending antenna lifespan. 5G signals experience significant attenuation during rain, a phenomenon known as "rain attenuation." This is because water droplets or films forming on the radome surface during rainfall absorb and reflect a large amount of electromagnetic waves, severely limiting 5G communication development. Therefore, preventing rainwater from forming droplets or films on the 5G radome surface is key to solving the "rain attenuation effect," requiring hydrophobic materials (contact angle > 90°, roll-off angle < 25°). Furthermore, 5G radomes are typically used outdoors. As is well known, outdoor environments are full of complex conditions, such as continuous rainfall, dust storms, ultraviolet radiation, corrosive media, high / low temperatures, freezing / melting, and snowfall. Therefore, protective materials also need to be weather-resistant. A highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film and its preparation method are proposed to solve the above problems. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the technical solution adopted by this invention is as follows: A high weather-resistant hydrophobic polyethylene tetrafluoroethylene film, comprising the following components by mass percentage:

[0004] 65.5%–70.5% ethylene-tetrafluoroethylene copolymer, 1.0%–2% UV absorber, 1.0%–2% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 10–14% titanium dioxide, 1.0%–2.0% hydrophobic agent;

[0005] The preparation method of the titanium dioxide is as follows:

[0006] The initial titanium dioxide, potassium 2,5-dihydroxybenzenesulfonate, sodium hydroxyethylsulfonate, potassium hydroxyethanesulfonate, and silane coupling agent were placed in a high-temperature mixing device, and the mixture was kept at 140℃~200℃ and stirred for 0.5h~2h.

[0007] Preferably, the ultraviolet absorber is at least one of triazine ultraviolet absorbers, benzotriazole ultraviolet absorbers, benzophenone ultraviolet absorbers, and salicylate ultraviolet absorbers.

[0008] Preferably, the light stabilizer is at least one of hindered amine light stabilizers, light-shielding light stabilizers, and organonickel chelating agents.

[0009] Preferably, the hydrophobic agent is at least one selected from acrylic hydrophobic agents, fluorohydrophobic agents, and silane hydrophobic agents.

[0010] A method for preparing a highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film includes the following steps:

[0011] Step 1: Take ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, acrylate toughening agent, nucleating agent and hydrophobic agent, mix them separately in a high-speed mixer, melt them and granulate them by extrusion.

[0012] Step 2: The film is fed into a casting machine for conveying, melting and extrusion, and then flows to the casting die. After being extruded through the die, it is stretched, cooled and shaped, and then trimmed and rolled up to obtain a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film.

[0013] Preferably, the mixing process conditions in step one are: mixing temperature of 20℃~50℃, mixing speed of 400rpm~800rpm, and mixing time of 20min~40min.

[0014] Preferably, the extrusion process conditions in step one are: extrusion temperature of 275℃~295℃ and screw speed of 300rpm~450rpm.

[0015] Preferably, in step two, the screw temperature in the casting machine is between 280°C and 310°C, and the die temperature is between 310°C and 350°C.

[0016] The mechanism of action of ultraviolet absorbers is mainly to prevent ultraviolet radiation by absorbing ultraviolet rays and converting them into heat energy; they have optical stability and can block the entry of ultraviolet rays, while light stabilizers are mainly scavengers of harmful free radicals. They capture the high molecular free radicals formed by the broken molecular chains of organic materials that have broken through the protection of ultraviolet absorbers and transform them into harmless and stable small molecular structures, thereby protecting the substrate; they increase the durability of polymers under light and reduce the rate of chemical reactions caused by light, thereby extending the service life of the substrate; the combined application of the two makes the produced high weather-resistant hydrophobic polyethylene tetrafluoroethylene film have better UV resistance and durability.

[0017] When selecting UV absorbers and light stabilizers for use in ETFE (ethylene-tetrafluoroethylene copolymer), the compatibility with the high processing temperature of the high-weather-resistant hydrophobic ETFE film needs to be considered. Therefore, the decomposition temperature (350℃) of the UV absorbers and light stabilizers must be higher than the processing temperature of the high-weather-resistant hydrophobic ETFE film to solve the defect of film breakage caused by additive decomposition during film formation.

[0018] The beneficial effects of this invention are as follows:

[0019] 1. The titanium dioxide modified with sulfonic acid group additives of this invention can provide lone pairs of electrons to TiO2, thereby forming a coordination effect, stabilizing the insufficiently coordinated Ti4+, and thus passivating the oxygen vacancies of TiO2, thereby inhibiting the photocatalytic reaction activity and improving the weather resistance of titanium dioxide. Moreover, the sulfonic acid group can increase the hydrophilicity of titanium dioxide, reduce surface energy, and facilitate its dispersion. The silane coupling agent and sodium hydroxyethyl sulfonate also undergo dehydration condensation with the hydroxyl groups on the surface of titanium dioxide, thereby firmly binding to the surface of titanium dioxide, improving the thermal stability of titanium dioxide, and having good compatibility with ETFE, making it more suitable as a processing aid for ETFE. At the same time, it can also enhance the interaction between molecular chains and improve its mechanical properties. In the plastics industry, titanium dioxide can improve the heat resistance and light resistance of plastics, increasing their service life. At the same time, due to the high opacity of titanium dioxide, it can ensure the low natural light transmittance (transmittance <10%) and low ultraviolet light transmittance of high weather-resistant hydrophobic polyethylene tetrafluoroethylene film, thereby protecting the underlying substrate.

[0020] 2. The ethylene-tetrafluoroethylene copolymer of the present invention adopts a powder structure, which has a larger contact area with additives and titanium dioxide, which is beneficial to the dispersion of titanium dioxide in the ethylene-tetrafluoroethylene copolymer, thereby reducing precipitation and the appearance of crystal points; at the same time, it can also enhance the interaction between molecular chains and improve its mechanical properties.

[0021] 3. The fluorohydrophobic agent of this invention has high heat resistance, weather resistance and chemical inertness; it can form a dense fluorocarbon layer, making the surface extremely hydrophobic, reducing the surface energy of the material, increasing the contact angle of the material, and reducing the roll-off angle of the material;

[0022] A high-weather-resistant and hydrophobic polyethylene-tetrafluoroethylene film is obtained by co-extruding ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, toughening agent, nucleating agent, and hydrophobic material, followed by casting and stretching. This film serves as a protective layer for radomes and antenna boxes, exhibiting excellent weather resistance, corrosion resistance, and hydrophobic properties. It is suitable as a protective layer for signal receivers, preventing rain attenuation effects on radomes and antenna boxes. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose.

[0024] To fully and clearly illustrate the specific implementation method of the present invention, the raw materials used are disclosed as follows:

[0025] Ethylene-tetrafluoroethylene copolymer: C-88AXP, melt flow rate 8.0 g / 10 min (297℃ / 5.0 kg), supplied by Asahi Glass Co., Ltd.

[0026] Titanium dioxide: R-103, supplied by Chemie / DuPont;

[0027] Acrylic toughening agent: Kane Ace® M-210, supplied by Kaneka Corporation, Japan;

[0028] Compatibilizer: Maleic anhydride-grafted polypropylene 1001CN, provided by Arkema China;

[0029] The ultraviolet absorbers UV-770, UV-2020, UV-234, and UV-1577 were provided by Nanjing Milan Chemical Co., Ltd.

[0030] The light stabilizers Chimassorb 2020 and Chimassorb 181 are supplied by BASF Group of Germany;

[0031] Hydrophobic agent: Nano-sized PTFE, provided by Nanjing Tianshi Co., Ltd.

[0032] Nucleating agent: Oxide nucleating agent, brand name RQT-CH, provided by Henan Ruichite Chemical Co., Ltd. Example

[0033] A highly weather-resistant, hydrophobic polyethylene tetrafluoroethylene film comprises the following components by weight percentage:

[0034] 70.5% ethylene-tetrafluoroethylene copolymer, 1.5% UV absorber, 1.5% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 10% titanium dioxide, 1% hydrophobic agent;

[0035] The preparation method of titanium dioxide is as follows:

[0036] The initial titanium dioxide, potassium 2,5-dihydroxybenzenesulfonate, sodium hydroxyethylsulfonate, potassium hydroxyethanesulfonate, and silane coupling agent were placed in a high-temperature mixing device, and the mixture was kept at 140℃~200℃ and stirred for 0.5h~2h.

[0037] The preparation method of this highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film includes the following steps:

[0038] Step 1: Take ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, acrylate toughening agent, nucleating agent, and hydrophobic agent, mix them separately in a high-speed mixer, melt them, and extrude them into granules. The mixing process conditions are: mixing temperature 20℃~50℃, mixing speed 400rpm~800rpm, mixing time 20min~40min. The extrusion process conditions are: extrusion temperature 275℃~295℃, screw speed 300rpm~450rpm.

[0039] Step 2: The film is fed into a casting machine for conveying, melting, and extrusion, and then flows to the casting die. The screw temperature in the casting machine is 280℃~310℃, and the die temperature is 310℃~350℃. After extrusion through the die, the film is stretched, cooled and shaped, trimmed, and wound to obtain a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film. Example

[0040] A highly weather-resistant, hydrophobic polyethylene tetrafluoroethylene film comprises the following components by weight percentage:

[0041] 68% ethylene-tetrafluoroethylene copolymer, 1.5% UV absorber, 1.5% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 12% titanium dioxide, 1.5% hydrophobic agent;

[0042] The preparation method of titanium dioxide is as follows:

[0043] The initial titanium dioxide, potassium 2,5-dihydroxybenzenesulfonate, sodium hydroxyethylsulfonate, potassium hydroxyethanesulfonate, and silane coupling agent were placed in a high-temperature mixing device, and the mixture was kept at 140℃~200℃ and stirred for 0.5h~2h.

[0044] The preparation method of this highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film includes the following steps:

[0045] Step 1: Take ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, acrylate toughening agent, nucleating agent, and hydrophobic agent, mix them separately in a high-speed mixer, melt them, and extrude them into granules. The mixing process conditions are: mixing temperature 20℃~50℃, mixing speed 400rpm~800rpm, mixing time 20min~40min. The extrusion process conditions are: extrusion temperature 275℃~295℃, screw speed 300rpm~450rpm.

[0046] Step 2: The film is fed into a casting machine for conveying, melting, and extrusion, and then flows to the casting die. The screw temperature in the casting machine is 280℃~310℃, and the die temperature is 310℃~350℃. After extrusion through the die, the film is stretched, cooled and shaped, trimmed, and wound to obtain a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film. Example

[0047] A highly weather-resistant, hydrophobic polyethylene tetrafluoroethylene film comprises the following components by weight percentage:

[0048] 65.5% ethylene-tetrafluoroethylene copolymer, 1.5% UV absorber, 1.5% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 14% titanium dioxide, 2.0% hydrophobic agent;

[0049] The preparation method of titanium dioxide is as follows:

[0050] The initial titanium dioxide, potassium 2,5-dihydroxybenzenesulfonate, sodium hydroxyethylsulfonate, potassium hydroxyethanesulfonate, and silane coupling agent were placed in a high-temperature mixing device, and the mixture was kept at 140℃~200℃ and stirred for 0.5h~2h.

[0051] The preparation method of this highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film includes the following steps:

[0052] Step 1: Take ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, acrylate toughening agent, nucleating agent, and hydrophobic agent, mix them separately in a high-speed mixer, melt them, and extrude them into granules. The mixing process conditions are: mixing temperature 20℃~50℃, mixing speed 400rpm~800rpm, mixing time 20min~40min. The extrusion process conditions are: extrusion temperature 275℃~295℃, screw speed 300rpm~450rpm.

[0053] Step 2: The film is fed into a casting machine for conveying, melting, and extrusion, and then flows to the casting die. The screw temperature in the casting machine is 280℃~310℃, and the die temperature is 310℃~350℃. After extrusion through the die, the film is stretched, cooled and shaped, trimmed, and wound to obtain a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film. Example

[0054] A highly weather-resistant, hydrophobic polyethylene tetrafluoroethylene film comprises the following components by weight percentage:

[0055] 68.5% ethylene-tetrafluoroethylene copolymer, 1.0% UV absorber, 1.0% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 12% titanium dioxide, 2.0% hydrophobic agent;

[0056] The preparation method of titanium dioxide is as follows:

[0057] The initial titanium dioxide, potassium 2,5-dihydroxybenzenesulfonate, sodium hydroxyethylsulfonate, potassium hydroxyethanesulfonate, and silane coupling agent were placed in a high-temperature mixing device, and the mixture was kept at 140℃~200℃ and stirred for 0.5h~2h.

[0058] The preparation method of this highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film includes the following steps:

[0059] Step 1: Take ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, acrylate toughening agent, nucleating agent, and hydrophobic agent, mix them separately in a high-speed mixer, melt them, and extrude them into granules. The mixing process conditions are: mixing temperature 20℃~50℃, mixing speed 400rpm~800rpm, mixing time 20min~40min. The extrusion process conditions are: extrusion temperature 275℃~295℃, screw speed 300rpm~450rpm.

[0060] Step 2: The film is fed into a casting machine for conveying, melting, and extrusion, and then flows to the casting die. The screw temperature in the casting machine is 280℃~310℃, and the die temperature is 310℃~350℃. After extrusion through the die, the film is stretched, cooled and shaped, trimmed, and wound to obtain a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film. Example

[0061] A highly weather-resistant, hydrophobic polyethylene tetrafluoroethylene film comprises the following components by weight percentage:

[0062] 67.5% ethylene-tetrafluoroethylene copolymer, 1.5% UV absorber, 1.5% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 12% titanium dioxide, 2.0% hydrophobic agent;

[0063] The preparation method of titanium dioxide is as follows:

[0064] The initial titanium dioxide, potassium 2,5-dihydroxybenzenesulfonate, sodium hydroxyethylsulfonate, potassium hydroxyethanesulfonate, and silane coupling agent were placed in a high-temperature mixing device, and the mixture was kept at 140℃~200℃ and stirred for 0.5h~2h.

[0065] The preparation method of this highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film includes the following steps:

[0066] Step 1: Take ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, acrylate toughening agent, nucleating agent, and hydrophobic agent, mix them separately in a high-speed mixer, melt them, and extrude them into granules. The mixing process conditions are: mixing temperature 20℃~50℃, mixing speed 400rpm~800rpm, mixing time 20min~40min. The extrusion process conditions are: extrusion temperature 275℃~295℃, screw speed 300rpm~450rpm.

[0067] Step 2: The film is fed into a casting machine for conveying, melting, and extrusion, and then flows to the casting die. The screw temperature in the casting machine is 280℃~310℃, and the die temperature is 310℃~350℃. After extrusion through the die, the film is stretched, cooled and shaped, trimmed, and wound to obtain a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film. Example

[0068] A highly weather-resistant, hydrophobic polyethylene tetrafluoroethylene film comprises the following components by weight percentage:

[0069] 66.5% ethylene-tetrafluoroethylene copolymer, 2.0% UV absorber, 2.0% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 12% titanium dioxide, 2.0% hydrophobic agent;

[0070] The preparation method of titanium dioxide is as follows:

[0071] The initial titanium dioxide, potassium 2,5-dihydroxybenzenesulfonate, sodium hydroxyethylsulfonate, potassium hydroxyethanesulfonate, and silane coupling agent were placed in a high-temperature mixing device, and the mixture was kept at 140℃~200℃ and stirred for 0.5h~2h.

[0072] The preparation method of this highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film includes the following steps:

[0073] Step 1: Take ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, acrylate toughening agent, nucleating agent, and hydrophobic agent, mix them separately in a high-speed mixer, melt them, and extrude them into granules. The mixing process conditions are: mixing temperature 20℃~50℃, mixing speed 400rpm~800rpm, mixing time 20min~40min. The extrusion process conditions are: extrusion temperature 275℃~295℃, screw speed 300rpm~450rpm.

[0074] Step 2: The film is fed into a casting machine for conveying, melting, and extrusion, and then flows to the casting die. The screw temperature in the casting machine is 280℃~310℃, and the die temperature is 310℃~350℃. After extrusion through the die, the film is stretched, cooled and shaped, trimmed, and wound to obtain a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film.

[0075] Samples were prepared using high weather-resistant hydrophobic polyethylene tetrafluoroethylene films (50 μm thick) from Examples 1-6. The shell material of the covers was PC. The performance of each sample was tested, and the results were recorded.

[0076] Visible light transmittance test: Using ASTM D1003 as the reference standard, the percentage of visible light with wavelengths in the range of 380 to 780 nm that passes through the sample surface is measured.

[0077] Ultraviolet transmittance test: Using an ultraviolet spectrophotometer, the absorbance of the sample in the wavelength range of 300-420 nm is measured;

[0078] Mechanical property testing: Using ISO527-3 as the reference standard, the tensile strength and elongation at break of the specimens in the transverse and longitudinal directions were tested at a tensile speed of 200 mm / min.

[0079] -40℃ TD Elongation at Break Test: Using GB / T1040.3-2006 as the reference standard, the transverse elongation at break of the sample after equilibration at -40℃ for 50 min was tested.

[0080] Contact angle test: The contact angle of the sample is tested with reference to ISO 15989.

[0081] Roll angle test: The roll angle of the specimen is tested with reference to ISO 19403-7.

[0082] Roughness test: The roughness of the sample is tested with reference to ANSI B46.1.

[0083] Table 1 is obtained:

[0084]

[0085] Saturated steam test: Using ASTM D-882 as the reference standard, the sample was placed under saturated humidity (100%RH), temperature 85℃, and pressure 49.1kpa for 96h. After the test, the mechanical properties, UV transmittance, yellowing value, contact angle, and roll-off angle of the sample were tested.

[0086] Table 2 is obtained:

[0087]

[0088] Constant humidity and heat test: Based on GB / T2423.3-2006, the sample was placed under the conditions of 93%RH and 40℃ for 3000h. After the test, the mechanical properties, ultraviolet transmittance, contact angle, roll-off angle and yellowing value of the sample were tested.

[0089] Table 3 is obtained:

[0090]

[0091] Cyclic temperature change test: Based on GB / T31034-2014, the sample is placed at 100℃ for 15 minutes, cooled to -40℃ for 15 minutes, and cycled 600 times. After the test, the mechanical properties, ultraviolet transmittance, contact angle, roll-off angle and yellowing value of the sample are tested.

[0092] Table 4 is obtained:

[0093]

[0094] Ultraviolet irradiation test: Using IEC61216-2005 as the reference standard, the sample was placed under an ultraviolet lamp for irradiation with an irradiation dose of 600 kWh. After the test, the mechanical properties, ultraviolet transmittance, contact angle, roll-off angle and yellowing value of the sample were tested.

[0095] Table 5 is obtained:

[0096]

[0097] According to the data in the table above, the initial contact angle and the contact angle after aging in Examples 1-6 are both >90°, which meets the hydrophobic condition. The initial roll-off angle and the roll-off angle after aging are both <25°, indicating that the high weather-resistant hydrophobic polyethylene tetrafluoroethylene film prepared by the present invention has excellent hydrophobic properties.

[0098] Under different aging conditions, the roll-off angle of the material did not change significantly (<25°), the contact angle remained >90°, and the yellowing was minimal (<1), indicating that the high weather-resistant hydrophobic polyethylene tetrafluoroethylene film prepared by this invention has excellent weather resistance and corrosion resistance.

[0099] Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art and related fields based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described and explained in the present invention, unless otherwise specified or limited, shall be implemented according to conventional means in the art.

Claims

1. A highly weather-resistant, hydrophobic polyethylene tetrafluoroethylene film, characterized in that, Includes the following components by mass percentage: 70.5% ethylene-tetrafluoroethylene copolymer, 1.5% UV absorber, 1.5% light stabilizer, 10% acrylate toughening agent, 5% compatibilizer, 0.5% nucleating agent, 10% titanium dioxide, 1% hydrophobic agent; The hydrophobic agent is nano-sized PTFE; The preparation method of the titanium dioxide is as follows: The initial titanium dioxide, potassium 2,5-dihydroxybenzenesulfonate, sodium hydroxyethylsulfonate, potassium hydroxyethanesulfonate, and silane coupling agent were placed in a high-temperature mixing device, and the mixture was kept at 140℃~200℃ and stirred for 0.5h~2h. The initial titanium dioxide is R-103.

2. The highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film according to claim 1, characterized in that: The ultraviolet absorber is at least one of triazine ultraviolet absorbers, benzotriazole ultraviolet absorbers, benzophenone ultraviolet absorbers, and salicylate ultraviolet absorbers.

3. The highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film according to claim 1, characterized in that: The light stabilizer is at least one of hindered amine light stabilizers, light-shielding light stabilizers, and organonickel chelating agents.

4. A method for preparing a highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film according to any one of claims 1-3, characterized in that, The following steps are involved: Step 1: Take ethylene-tetrafluoroethylene copolymer, titanium dioxide, ultraviolet absorber, light stabilizer, compatibilizer, acrylate toughening agent, nucleating agent and hydrophobic agent, mix them separately in a high-speed mixer, melt them and granulate them by extrusion. Step 2: The film is fed into the casting machine for conveying, melting and extrusion, and then flows to the casting die. After being extruded through the die, it is stretched, cooled and shaped, and then trimmed and rolled up to obtain a high weather-resistant hydrophobic polyethylene tetrafluoroethylene film. The mixing conditions in step one are as follows: mixing temperature is 20℃~50℃, mixing speed is 400rpm~800rpm, and mixing time is 20min~40min; In step two, the screw temperature in the casting machine is between 280℃ and 310℃, and the die temperature is between 310℃ and 350℃.

5. The method for preparing a highly weather-resistant hydrophobic polyethylene tetrafluoroethylene film according to claim 4, characterized in that: The extrusion process conditions in step one are: extrusion temperature of 275℃~295℃ and screw speed of 300rpm~450rpm.

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