Transparent energy-saving window film master batch and preparation method thereof, and window film

Abstract

The application discloses a transparent heat-insulating energy-saving window film master batch and a preparation method and window film thereof. The transparent heat-insulating energy-saving window film master batch comprises nanometer fluorinated tungsten bronze powder, polydimethylsiloxane, a dispersing agent and a polymer carrier. The nanometer fluorinated tungsten bronze powder is a core-shell structure composed of nanometer tungsten bronze particles externally grafted with fluorine-containing silane. The molecular structure of the nanometer tungsten bronze is M x WO3, 0.01<=x<=0.30, the mass ratio of the fluorine-containing silane and the nanometer tungsten bronze powder is 1:201:15. The fluorination modification of the surface of the nanometer tungsten bronze can improve the agglomeration of the nanometer tungsten bronze, ensure that the particle size of the modified powder is less than or equal to 100 nm in the plastic product, improve the infrared blocking rate and the visible light transmittance, improve the 8-13 mu infrared emissivity, and make the nanometer tungsten bronze have the effect of radiating heat. Meanwhile, by controlling the mass ratio of the fluorine-containing silane and the nanometer tungsten bronze, the compatibility of the powder in the polymer carrier can be improved, and the powder has high 8-13 mu infrared emissivity.

Description

Technical Field

[0001] This invention relates to the field of functional materials technology, specifically to transparent heat-insulating and energy-saving window film masterbatch and its preparation method, and window film. Background Technology

[0002] If a car is exposed to direct sunlight for an extended period while driving, the interior temperature can rise rapidly, leading to overheating and negatively impacting the driving experience and vehicle performance. The primary cause of this temperature increase is infrared heat radiation, which is why car manufacturers now often use window films with infrared-blocking properties to address this issue.

[0003] Most existing window films currently use cesium tungsten bronze as an infrared blocking agent. After absorbing infrared light, it generates a lot of heat, which on the one hand significantly shortens the lifespan of the window film, and on the other hand, the heat from the film material is transferred to the car interior, causing the interior temperature to rise. Summary of the Invention

[0004] To overcome the above-mentioned shortcomings, the present invention aims to provide a transparent heat-insulating and energy-saving window film masterbatch, its preparation method, and the window film prepared using the masterbatch. The window film prepared using this masterbatch not only has high infrared blocking rate and high visible light transmittance, but also has a radiative cooling effect, which can emit the heat generated by the window film into outer space in the form of a typical atmospheric window wavelength (8-13μm), while also having water-repellent and anti-fouling effects.

[0005] One objective of this invention is to provide a transparent, heat-insulating, and energy-saving window film masterbatch, comprising: nano-tungsten bronze fluoride powder, polydimethylsiloxane, a dispersant, and a polymer carrier. The nano-tungsten bronze fluoride powder has a core-shell structure composed of nano-tungsten bronze particles grafted with fluorinated silanes. The molecular structure of the nano-tungsten bronze is M... x WO3, 0.01≤x≤0.30, wherein the mass ratio of the fluorinated silane and the nano-tungsten bronze powder is 1:20. A ratio of 1:15 indicates that excessive perfluorosilane content leads to poor compatibility of the modified powder in the resin, affecting optical performance. Insufficient perfluorosilane, on the one hand, fails to effectively improve the agglomeration of nano-tungsten bronze powder, and on the other hand, results in insufficient emissivity in the 8-13μm range, affecting heat dissipation.

[0006] The present invention has the following beneficial effects: ① By fluorinating the surface of nano-tungsten bronze, on the one hand, the agglomeration of nano-tungsten bronze can be improved, ensuring that the particle size of the modified powder in plastic products is ≤100nm, thereby improving infrared blocking rate and visible light transmittance; on the other hand, the infrared emissivity of 8-13μm can be increased, giving it a radiative heat dissipation effect. Therefore, while ensuring that the window film has high infrared absorption, most of the absorbed infrared light is emitted outside the vehicle, effectively improving the temperature rise inside the vehicle. ② By controlling the mass ratio of fluorinated silane to nano-tungsten bronze to 1:20 A ratio of 1:15 can improve the compatibility between powder and polymer carrier while maintaining a high infrared emissivity of 8-13μm and a high visible light transmittance. ③ By introducing polydimethylsiloxane, it can form a micro-phase separation on the surface of the masterbatch after it forms a thin film, which can produce the effects of anti-reflection, anti-reflection, hydrophobic and oleophobic, improve the light transmittance of the film and reduce the oil film phenomenon of the window film. ④ Introducing polydimethylsiloxane can also improve the 8-13μm infrared emission effect, enhance the radiation heat dissipation effect, reduce the crystallinity of the polymer carrier, and improve the visible light transmittance of the film product.

[0007] Furthermore, the mass ratio of the nano-tungsten fluoride bronze to polydimethylsiloxane is 4:1. 10:1. For example, it could be 5:1. 9:1, or 5:1 The ratio can be 8:1, or 5:1, 6:1, 7:1, 7.5:1, or 20:3. Polydimethylsiloxane and nano-tungsten fluoride bronze can cause microscopic phase separation on the surface of the film formed from the masterbatch. This reduces reflectivity and increases light transmittance, improving the visible light transmittance of the film. It also achieves hydrophobic and oleophobic effects, reducing the oil film phenomenon in the window film. However, a reasonable ratio between the amount of polydimethylsiloxane and nano-tungsten fluoride bronze should be maintained. If the polydimethylsiloxane content is too low, the phase separation phenomenon will be insignificant, failing to achieve the desired effect; if the polydimethylsiloxane content is too high, the phase separation will be obvious, severely affecting the film haze.

[0008] Furthermore, the fluorinated silane is selected from at least one of perfluorooctyltriethoxysilane, perfluorohexyltriethoxysilane, and perfluorodecyltriethoxysilane.

[0009] Furthermore, the polymer carrier is at least one selected from polyethylene terephthalate, polyurethane, polyethylene, and polypropylene.

[0010] Furthermore, the weight ratio of each component is as follows: 1-50 parts of nano-tungsten fluoride bronze powder, 1-5 parts of polydimethylsiloxane, 1-10 parts of dispersant, and 35-100 parts of polymer carrier.

[0011] Furthermore, the nano-fluorinated tungsten bronze powder is prepared from fluorinated silane and nano-tungsten bronze powder in a mass ratio of 3:50.

[0012] Furthermore, M can be any one of alkali metals or alkaline earth metals.

[0013] Furthermore, M is cesium. Cesium has a large atomic radius, resulting in numerous surface defects after the formation of stable cesium tungsten bronze nanopowder, which further enhances its infrared absorption capability.

[0014] This invention also provides a method for preparing transparent heat-insulating and energy-saving window film masterbatch, which includes the following steps: STEP 01: Cesium tungsten bronze nanopowder is prepared in one step using a hydrothermal method. This process is easy to control and simple, and the resulting powder has excellent dispersibility and chemical stability. STEP 02: Fluorosilane Grafting: Fluorosilane and nano-tungsten bronze powder are mixed in ethanol and stirred at high speed. The pH of the solution is adjusted to 7 using ammonia. 9. Then filter, wash and dry; STEP 03: Mix and dry the raw materials for preparing transparent heat-insulating and energy-saving window film masterbatch; STEP 04: The material prepared in step STEP 03 is fed into a twin-screw extruder for extrusion granulation: After being fully plasticized in the twin screw, the mixed material is sheared and dispersed evenly by the dispersing element in the twin screw, extruded through a round die, cooled in a water tank, and drawn by a string to a pelletizer to be cut into cylindrical particles with a length of 3mm ± 1mm ​​and a diameter of 2.5mm ± 1.5mm; the twin-screw extruder is equipped with a vacuum device, and the length-to-diameter ratio of the twin-screw extruder is not less than 40:1; the process temperature during extrusion is 240°C. 270℃.

[0015] The present invention also provides a transparent heat-insulating and energy-saving window film, which is prepared from the aforementioned masterbatch or by the aforementioned method.

[0016] This invention utilizes transparent heat-insulating and energy-saving window film masterbatch with an overall powdery appearance to prepare window film. Compared with the method of coating vehicle windows with functional coatings that have a liquid flowable appearance, the performance is more stable, the product consistency is stronger, it is more suitable for industrialized and standardized mass production, the parameters are precise and controllable, and there are no defects such as color difference and uneven thickness of coating. Detailed Implementation

[0017] The preferred embodiments of the present invention will now be described in detail so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0018] The transparent heat-insulating and energy-saving window film masterbatch of the present invention comprises: nano-tungsten bronze fluoride powder, polydimethylsiloxane, dispersant, and polymer carrier. The nano-tungsten bronze fluoride powder has a core-shell structure composed of nano-tungsten bronze particles grafted with fluorinated silanes. The molecular structure of the nano-tungsten bronze is M... x WO3, 0.01≤x≤0.30, with a mass ratio of fluorinated silane to nano-tungsten bronze powder of 1:20. A ratio of 1:15 indicates that excessive fluorinated silane content leads to excessive impurities, which increases the haze of the film, resulting in poor compatibility of the modified powder in the resin and affecting optical performance. Insufficient fluorinated silane content, on the one hand, cannot effectively improve the agglomeration of nano-tungsten bronze powder, and on the other hand, results in insufficient emissivity of 8-13μm, affecting heat dissipation.

[0019] In some embodiments, the dispersant of the present invention is PE wax. The present invention controls the particle size of nano-cesium tungsten bronze powder in the masterbatch to ≤100nm, thus it has an extremely high specific surface area and surface energy, making it very easy to agglomerate. Therefore, when used in conjunction with PE wax, it penetrates into the nano-agglomerates after melting, and the molecular chains coat the particles, which has the dual effect of steric hindrance and lubrication to prevent agglomeration. It has strong nanoscale dispersion ability, and is not easy to agglomerate or precipitate when highly filled.

[0020] This invention modifies the surface of nano-tungsten bronze with fluorination. On one hand, it improves the agglomeration problem of nano-tungsten bronze, ensuring that the particle size of the modified powder in plastic products does not exceed 100 nm, thus improving infrared blocking and visible light transmittance. On the other hand, it increases the infrared emissivity of the material in the 8-13 μm wavelength band, enabling the material to have radiative heat dissipation. By controlling the mass ratio of fluorinated silane to nano-tungsten bronze, the compatibility of the powder in the polymer carrier can be improved while ensuring high infrared emissivity in the 8-13 μm wavelength band. The introduction of polydimethylsiloxane allows it to work in conjunction with the nano-fluorinated tungsten bronze powder, resulting in micro-phase separation on the surface after the masterbatch is formed into a film. This achieves anti-reflective and anti-reflective effects, as well as hydrophobic and oleophobic properties, improving the film transmittance while reducing the oil film phenomenon. The introduction of polydimethylsiloxane also enhances the infrared emission effect of the material in the 8-13 μm wavelength band, strengthens radiative heat dissipation, and reduces the crystallinity of the polymer carrier, thereby increasing the visible light transmittance of the film product.

[0021] In some embodiments, the mass ratio of fluorinated silane to nano-tungsten bronze powder is 1:16-1:18; in some embodiments, the mass ratio of fluorinated silane to nano-tungsten bronze powder is 3:50.

[0022] In some embodiments, the mass ratio of nano-tungsten fluoride bronze to polydimethylsiloxane is 4:1. 10:1. Polydimethylsiloxane and nano-tungsten fluoride bronze can cause microscopic phase separation on the surface of the film formed by the masterbatch. On the one hand, it can reduce reflection and increase light transmittance, improving the visible light transmittance of the film. On the other hand, it can achieve hydrophobic and oleophobic effects, reducing the oil film phenomenon of the window film. If the content of polydimethylsiloxane is too low, the phase separation phenomenon will not be obvious and the expected effect cannot be achieved. If the content of polydimethylsiloxane is too high, the phase separation will be obvious, which will seriously affect the haze of the film.

[0023] In some embodiments, the mass ratio of nano-tungsten fluoride bronze to polydimethylsiloxane is 5:1. 9:1; In some embodiments, the mass ratio of nano-tungsten fluoride bronze to polydimethylsiloxane is 5:1. 8:1; in some embodiments, the mass ratio is 7.5:1; in some embodiments, the mass ratio is 5:1; in some embodiments, the mass ratio is 20:3. In some embodiments, the fluorinated silane is selected from at least one of perfluorooctyltriethoxysilane, perfluorohexyltriethoxysilane, and perfluorodecyltriethoxysilane.

[0024] In some embodiments, the polymer carrier is at least one of polyethylene terephthalate, polyurethane, polyethylene, and polypropylene.

[0025] In some embodiments, the weight ratio of each component is as follows: 1-50 parts of nano-tungsten fluoride bronze powder, 1-5 parts of polydimethylsiloxane, 1-10 parts of dispersant, and 35-100 parts of polymer carrier. In some embodiments, the amount of nano-tungsten fluoride bronze powder is 5-40 parts, or 7-35 parts, or 10-30 parts, or 21.2 parts, or 10.6 parts. Correspondingly, the mass ratio of fluorinated silane to nano-tungsten bronze powder can be 3:50.

[0026] In some implementations, M is any one of alkali metals or alkaline earth metals.

[0027] In some implementations, M is cesium. Cesium has a large atomic radius, resulting in more surface defects in the stable cesium tungsten bronze nanopowder, which further enhances its infrared absorption capability.

[0028] The preparation method of the transparent heat-insulating and energy-saving window film masterbatch of the present invention includes the following steps: STEP 01: Cesium tungsten bronze nanopowder is prepared in one step using a hydrothermal method. This process is easy to control and simple, and the resulting powder has excellent dispersibility and chemical stability. STEP 02: Fluorosilane Grafting: Fluorosilane and nano-tungsten bronze powder are mixed in ethanol and stirred at high speed. The pH of the solution is adjusted to 7 using ammonia. 9. Then filter, wash and dry; STEP 03: Mix and dry the raw materials for preparing transparent heat-insulating and energy-saving window film masterbatch; STEP 04: The material prepared in step STEP 03 is fed into a twin-screw extruder for extrusion granulation: After being fully plasticized in the twin screw, the mixed material is sheared and dispersed evenly by the dispersing element in the twin screw, extruded through a round die, cooled in a water tank, and drawn by a string to a pelletizer to be cut into cylindrical particles with a length of 3mm ± 1mm ​​and a diameter of 2.5mm ± 1.5mm; the twin-screw extruder is equipped with a vacuum device, and the length-to-diameter ratio of the twin-screw extruder is not less than 40:1; the process temperature during extrusion is 240°C. 270℃.

[0029] The present invention will now be described in conjunction with specific embodiments and comparative examples.

[0030] The raw materials used in this invention are sourced as follows: nano-cesium tungsten bronze powder was purchased from Zhejiang Chongchuan New Material Technology Co., Ltd., product number ZC-WK; perfluorodecyltriethoxysilane was purchased from Zhongshan Dixin Chemical Co., Ltd., product number yaner; polydimethylsiloxane was purchased from Dow Corning, model number PMX-200; polyethylene terephthalate powder (PET) was purchased from Jiangyin Ximalun Environmental Protection Technology Co., Ltd., product number CB602; polyurethane powder was purchased from Dongguan Jieshun Plastic Raw Materials Co., Ltd., grade 106. PET granules were purchased from Sinopec Shanghai Petrochemical Co., Ltd., grade number N150. PE wax was purchased from Honeywell, model number AC-316A.

[0031] Example 1: This embodiment is a transparent heat-insulating and energy-saving window film masterbatch, which is prepared from the following raw materials by weight: 20 parts of nano cesium tungsten bronze powder, 1.2 parts of perfluorodecyltriethoxysilane, 3 parts of polydimethylsiloxane, 5 parts of dispersant, and 70.8 parts of polyethylene terephthalate (PET) carrier.

[0032] Prepare according to the following steps: ①Cs was prepared in one step using a hydrothermal method. x WO3 nanoparticles, x=0.3, particle size ≤50nm; ② The nano-cesium tungsten bronze powder was mixed with perfluorodecyltriethoxysilane in ethanol by high-speed stirring. The pH was adjusted to 8 with ammonia water. The mixture was then filtered, washed, and dried to obtain core-shell structured nano-tungsten fluoride bronze. ③ Mix and dry the nano-tungsten fluoride bronze, polydimethylsiloxane, dispersant, and PET carrier; ④ The mixture is fed into a twin-screw extruder for extrusion granulation. The extruder has a length-to-diameter ratio of 45:1 and is equipped with a vacuum device. The extrusion temperature is 250℃, and masterbatch with a length of 3mm and a diameter of 2.5mm is obtained.

[0033] Example 2: This embodiment is a transparent heat-insulating and energy-saving window film masterbatch, which is prepared from the following raw materials by weight: 30 parts of nano-cesium tungsten bronze powder, 1.8 parts of perfluorodecyltriethoxysilane, 4 parts of polydimethylsiloxane, 6 parts of dispersant, and 58.2 parts of polyurethane (PU) carrier. The preparation method is the same as in Example 1.

[0034] The polyurethane carrier selected in this embodiment has the characteristics of low melting point and high viscosity. After melting, polyurethane has high viscosity, good viscoelasticity, and strong wetting power, which enables it to form a better combination with cesium tungsten bronze nanoparticles, resulting in more complete coating and less agglomeration. Therefore, even with a relatively small weight proportion of polyurethane carrier, the masterbatch still has high overall performance.

[0035] Example 3: This embodiment is a transparent heat-insulating and energy-saving window film masterbatch, which is prepared from the following raw materials by weight: 10 parts of nano-cesium tungsten bronze powder, 0.6 parts of perfluorodecyltriethoxysilane, 2 parts of polydimethylsiloxane, 4 parts of dispersant, and 83.4 parts of polyethylene (PE) carrier. The preparation method is the same as in Example 1.

[0036] Comparative Example 1: The only difference from Example 1 is that no fluorinated silane (perfluorodecyltriethoxysilane) is added, and there is no fluorination modification. All other components, proportions, and preparation methods are the same as in Example 1.

[0037] Comparative Example 2: The only difference from Example 1 is that the amount of perfluorodecyltriethoxysilane added is 2.5 parts (i.e., the mass ratio of fluorinated silane to nano-tungsten bronze powder is not 1:20). (The ratio range is 1:15), and the remaining components, proportions, and preparation methods are the same as in Example 1.

[0038] Comparative Example 3: The only difference from Example 1 is that polydimethylsiloxane is not added; the other components, proportions, and preparation methods are the same as in Example 1.

[0039] Comparative Example 4: The only difference from Example 1 is that the amount of polydimethylsiloxane added is 6 parts (i.e., the mass ratio of nano-tungsten fluoride bronze to polydimethylsiloxane exceeds 4:1). (The mass ratio is within the range of 10:1). The remaining components, proportions, and preparation methods are the same as in Example 1.

[0040] Thin film samples were prepared using the masterbatches obtained in Examples 1-3 and Comparative Examples 1-4, and the performance of the films was tested.

[0041] Thin film sample preparation: BPOET films with a cesium tungsten bronze powder content of 1.5% and a thickness of 40 μm were prepared by mixing the masterbatches from Examples 1-3 and Comparative Examples 1-4 with PET particles through casting and biaxial stretching. The infrared blocking rate, visible light transmittance, haze, emissivity in the 8-13 μm band, and hydrophobic angle were then tested. The infrared blocking rate and visible light transmittance were directly tested using the LS182 optical transmittance meter.

[0042] The haze value was directly measured using a KS1310 haze meter.

[0043] Emissivity in the 8-13 μm band: Fourier transform infrared spectroscopy was used to measure the emissivity of BOPET samples in the 769-1250 cm⁻¹ band. -1 The reflectivity and transmittance are given by the equation: Emissivity = 1 - Reflectivity - Transmittance.

[0044] Contact angle: Using the CA300 fully automatic contact angle measuring instrument, in a constant temperature and dust-free environment, a precise amount of deionized water is dropped onto the flat surface of the window film using a precision syringe. The lens of the device captures the outline of the droplet, and the software automatically fits and calculates the contact angle between the solid, liquid and gas phases. This angle is the hydrophobic contact angle.

[0045] Table 1 shows a comparison of the performance of the window films prepared using the masterbatches from Examples 1-3 and Comparative Examples 1-4: Table 1. Comparison of window film performance prepared using masterbatches from various samples:

[0046] The experimental results show that the window films prepared using the masterbatches of Examples 1-3 of this invention have high infrared blocking, high light transmittance, high radiative cooling, low haze, and strong hydrophobicity and antifouling properties, exhibiting the best overall performance. The masterbatch formulation of this invention is well-balanced; with only 10 parts by weight of nano-cesium tungsten bronze powder and 0.6 parts by weight of perfluorodecyltriethoxysilane (Example 3), the window films prepared using this masterbatch can achieve a high infrared blocking rate. However, if the amount of nano-cesium tungsten bronze powder added is too high, the infrared blocking rate of the window film prepared using the masterbatch does not increase proportionally, and may even decrease (Example 2). The reason may be that when the amount of nano-cesium tungsten bronze added is within a suitable range, the nano-cesium tungsten bronze particles can be uniformly dispersed in the masterbatch, and each particle can effectively absorb infrared light. However, if the amount of nano-cesium tungsten bronze powder added is too high, the particle spacing is smaller than the van der Waals attraction distance, and they are prone to agglomeration. As a result, the number of effective particles that can actually absorb infrared light decreases significantly, thus causing the infrared blocking rate to decrease instead of increase.

[0047] If the nano-tungsten bronze particles are not fluorinated (Comparative Example 1), the powder is prone to agglomeration, has low emissivity, poor heat dissipation, poor optical performance, and deteriorates hydrophobicity. Therefore, fluorination modification of nano-tungsten bronze particles can improve the overall performance of the window film. However, if the proportion of perfluorosilane added is too high, it will result in poor compatibility with the carrier, increased haze, and decreased light transmittance (Comparative Example 2). In the masterbatch of this application, polydimethylsiloxane is added, and the mass ratio of nano-fluorinated tungsten bronze to polydimethylsiloxane is controlled at 4:1. A ratio of 10:1 can also reduce haze and significantly improve the hydrophobicity and optical performance of the window film. However, if polydimethylsiloxane is used in excess, excessive phase separation will occur, resulting in a significant increase in haze and a deterioration in optical performance (Comparative Example 4).

[0048] Comparative Example 3, without the addition of polydimethylsiloxane, resulted in a window film with higher haze and significantly inferior hydrophobic properties compared to the examples. This further validates the rationality of the component ratio design in this application. Only by preparing the masterbatch according to the specified ratio of each component can a transparent, heat-insulating, and energy-saving window film with excellent comprehensive performance be prepared. This invention, through fluorination modification of nano-tungsten bronze and a reasonable component ratio, yields a masterbatch that, when used to prepare window films, simultaneously achieves high infrared blocking rate, high visible light transmittance, and low haze, while also possessing excellent radiative cooling performance and hydrophobic and anti-fouling properties, meeting the practical application requirements of window films.

[0049] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A transparent heat-insulating and energy-saving window film masterbatch, characterized in that, include: The composition includes nano-tungsten fluoride bronze powder, polydimethylsiloxane, dispersant, and polymer carrier. The nano-tungsten fluoride bronze powder has a core-shell structure composed of nano-tungsten bronze particles grafted with fluorinated silane. The molecular structure of the nano-tungsten bronze is M. x WO3, 0.01≤x≤0.30, wherein the mass ratio of the fluorinated silane and the nano-tungsten bronze powder is 1:

20. 1:

15.

2. The transparent heat-insulating and energy-saving window film masterbatch according to claim 1, characterized in that, The mass ratio of the nano-fluorinated tungsten bronze to polydimethylsiloxane is 4:

1. 10:

1.

3. The transparent heat-insulating and energy-saving window film masterbatch according to claim 1 or 2, characterized in that, The fluorinated silane is selected from at least one of perfluorooctyltriethoxysilane, perfluorohexyltriethoxysilane, and perfluorodecyltriethoxysilane.

4. The transparent heat-insulating and energy-saving window film masterbatch according to claim 1 or 2, characterized in that, The polymer carrier is at least one of polyethylene terephthalate, polyurethane, polyethylene, and polypropylene.

5. The transparent heat-insulating and energy-saving window film masterbatch according to claim 1 or 2, characterized in that, The weight ratio of each component is as follows: 1-50 parts of nano-tungsten fluoride bronze powder, 1-5 parts of polydimethylsiloxane, 1-10 parts of dispersant, and 35-100 parts of polymer carrier.

6. The transparent heat-insulating and energy-saving window film masterbatch according to claim 5, characterized in that, The nano-fluorinated tungsten bronze powder is prepared from fluorinated silane and nano-tungsten bronze powder in a mass ratio of 3:

50.

7. The transparent heat-insulating and energy-saving window film masterbatch according to claim 1 or 2, characterized in that, M is any one of the alkali metals or alkaline earth metals.

8. The transparent heat-insulating and energy-saving window film masterbatch according to claim 7, characterized in that, M is cesium.

9. A method for preparing the transparent heat-insulating and energy-saving window film masterbatch according to any one of claims 1-8, characterized in that, Includes the following steps: STEP 01: One-step preparation of cesium tungsten bronze nanopowder using a hydrothermal method; STEP 02: Fluorosilane Grafting: Fluorosilane and nano-tungsten bronze powder are mixed in ethanol and stirred at high speed. The pH of the solution is adjusted to 7 using ammonia.

9. Then filter, wash and dry; STEP 03: Mix and dry the raw materials for preparing transparent heat-insulating and energy-saving window film masterbatch; STEP 04: The material prepared in step STEP 03 is fed into a twin-screw extruder for extrusion granulation. After being fully plasticized in the twin screw, the material is sheared and dispersed evenly by the dispersing element in the twin screw. The material is then extruded, cooled, and drawn into a pelletizer to be cut into granules. The twin-screw extruder is equipped with a vacuum device, and its length-to-diameter ratio is not less than 40:

1. The extrusion process temperature is 240°C. 270℃.

10. A transparent, heat-insulating, and energy-saving window film, characterized in that, The masterbatch is prepared by any one of claims 1-8, or by the preparation method described in claim 9.

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