Fluoropolymer-modified single-layer graphene and method of making the same

Abstract

The application discloses a fluorine-containing polymer modified single-layer graphene oxide and a preparation method thereof. The graphene oxide is exfoliated into single layers in an organic solvent under ultrasonic assistance and nitrogen protection; meanwhile, a fluorine-containing polymer or a perfluoro acid anhydride containing active reaction end groups is used as a modifier to react with oxygen-containing groups such as hydroxyl groups on the surface of the graphene oxide, so that the fluorine-containing polymer modified single-layer graphene oxide is prepared. The preparation method of the fluorine-containing polymer modified single-layer graphene oxide has the advantages of simple process, complete reaction, mild conditions, controllable product structure and the like. The obtained fluorine-containing polymer modified single-layer graphene oxide can be highly dispersed in various solvents and matrices and keep a good single-layer state, effectively overcomes the problems of easy agglomeration and difficult dispersion of existing (modified) graphene oxides, and can be widely applied to the fields of design and preparation of graphene oxide-based high-performance composite materials and the like.

Description

Technical Field

[0001] This invention belongs to the field of nanomaterials technology, specifically relating to a method for preparing fluoropolymer-modified monolayer graphene oxide. Background Technology

[0002] Graphene oxide (GO) is an important oxygen-containing derivative of graphene. It is a quasi-two-dimensional carbon nanomaterial formed by introducing a certain amount of covalent bonds such as CO into the hexagonal carbon network of graphene. Given that the carbon atoms in the oxidized portion of GO will have a planar sp... 2 The sp hybridization transforms into a twisted tetrahedral configuration 3 Hybridization means that GO no longer possesses the strictly planar structure of graphene, but instead exhibits a quasi-planar structure with some wrinkles. Furthermore, the higher the degree of oxidation, the more sp... 3 The higher the proportion of hybrid carbon atoms, the greater the degree of surface wrinkling or deviation from planar structure. Therefore, GO with medium to low oxidation levels generally has an almost flat carbon network structure. The surface and edges of GO are rich in oxygen-containing functional groups such as hydroxyl, carboxyl, carbonyl, and epoxy groups. The presence of these groups gives GO good hydrophilicity and certain reactivity. In addition, GO also has low density, large specific surface area, good electrical and thermal conductivity, and excellent mechanical properties. These structural and performance advantages have made GO an increasingly popular high-performance functional filler, and it is widely used in the design and synthesis of advanced composite materials. Practice shows that strong hydrogen bonds exist between the oxygen-containing groups such as hydroxyl groups on the GO surface. These hydrogen bonds, along with van der Waals forces and other interactions, cause strong mutual attraction between GO layers, leading to spontaneous aggregation of GO. This is detrimental to the high dispersion and uniform distribution of GO in dispersants and composite materials, making it difficult to maximize the application of GO as a functional filler. Improving the dispersion of GO in the matrix has become one of the prerequisites and key factors for improving the performance of composite materials.

[0003] Currently, GO can be modified mainly through two methods: covalent modification and non-covalent modification, to improve its dispersibility in dispersants or composite matrices. Non-covalent modification results in weak interactions between GO and modifier molecules, leading to unstable properties and limited applications. Covalent modification, on the other hand, involves chemical reactions between hydroxyl groups and reactive groups in the modifier molecules on the GO surface, grafting the modifier molecules onto the GO surface via covalent bonds. This method is beneficial for improving the performance of modified GO and has attracted attention and application in research.

[0004] The literature (Polymers, 2018, 10, 569) reports a method for preparing polymer composite films by grafting and modifying GO with perfluoropolyether. The method utilizes a perfluoropolyether with a molecular weight of approximately 2500 as a modifier. The end group of the modifier reacts with GO using a carboxyl group, while the group reacting with the end carboxyl group on the GO surface is an epoxy group. However, given that the perfluoropolyether is a viscous liquid, it is difficult to disperse in various solvents, resulting in low reactivity of its end carboxyl groups. Furthermore, the most abundant oxygen-containing functional group on the GO surface is the hydroxyl group, which is more abundant than the epoxy group. Therefore, both the mass transfer and diffusion capabilities of the modifier and the concentration and activity of the reactive groups are unfavorable for the covalent bond modification of the GO surface. Even with the use of a catalyst, the GO surface modification remains insufficient, leading to a low grafting rate of the perfluoropolyether. The hydroxyl groups on the GO surface are almost entirely retained and participate in the reaction. Strong hydrogen bonds and other interactions still exist between the GO layers, making it difficult for the modifier molecules to overcome these interactions and react with the epoxy groups between the GO layers. Therefore, the grafting reaction actually occurs on the outer surface of multilayer GO, and the resulting modified GO is still a multilayer structure with low dispersion.

[0005] Chinese patent CN116750759A discloses a method for preparing polysiloxane-modified monolayer graphene oxide (GO) using monolayer GO as a raw material. The method involves the condensation reaction between hydroxyl groups on the GO surface and Si-H groups of hydrogen-containing polysiloxanes under trifluorophenylboron catalysis to obtain polysiloxane-modified monolayer GO. The abundant oxygen-containing functional groups (hydroxyl, carboxyl, epoxy, and carbonyl groups) on the surface of the monolayer GO raw material endow it with good hydrophilicity and certain reactivity. However, in applications, it is difficult to prepare and effectively supply monolayer GO in large quantities. Even when small amounts of monolayer GO are prepared using methods such as ultrasound-assisted techniques, the monolayer structure cannot be maintained for a long time. This is because the numerous hydrogen bonds and other strong interactions between the aforementioned oxygen-containing functional groups cause spontaneous aggregation of monolayer GO into multiple layers. Therefore, in practice, the spontaneous aggregation of monolayer GO in the preparation of this polysiloxane-modified monolayer GO is accompanied by the condensation reaction between hydroxyl groups and Si-H, and the two processes compete with each other, making it difficult to prepare a truly modified monolayer GO. Furthermore, the specification does not include the necessary experimental results to prove that the obtained modified GO product is monolayer.

[0006] Fluoropolymers (FPs) are a class of polymers formed by homopolymerization / copolymerization of fluorinated monomers or copolymerization of fluorinated monomers with ordinary monomers, resulting in a large number of CF covalent bonds in the polymer chain. Fluorine atoms have small radii, the highest electronegativity, and strong electron-withdrawing ability, and the bond energy of CF covalent bonds is very high (536 kJ·mol⁻¹). -1In fluorinated polymer chains, most of the electron clouds of the CF bonds are distributed around the fluorine atoms. Due to the strong mutual repulsion between electrons, highly fluorinated groups such as CF and -CF3 tend to stay as far apart as possible, extending outward around the macromolecular backbone in a roughly helical pattern. This forms a fluorinated outer layer or protective layer on the CC backbone, making it difficult for external light and heat radiation, solvents, oxidants, and chemicals to penetrate the fluorine protective layer and act on the polymer backbone (causing it to break and degrade). This special structure endows FPs with many excellent properties, such as low-temperature resistance, high-temperature resistance, solvent resistance, chemical resistance, radiation resistance, self-lubrication, excellent electrical properties, optical properties, and surface properties. It also endows composite materials designed and prepared based on FPs with excellent comprehensive properties and broad application prospects.

[0007] Propylene hexafluoropropylene oxide oligomers / polymers (PHFPO) are a typical example of polymeric functional materials (FPs). Literature (Macromolecules, 2012, 45, 4907) shows that PHFPO can be controllably prepared via anionic ring-opening polymerization of hexafluoropropylene oxide (HFPO). This preparation method is highly efficient, low-cost, and selective. More importantly, the PHFPO prepared by anionic ring-opening polymerization of HFPO has highly reactive acyl fluoride groups at its end groups. These acyl fluoride groups can react with hydroxyl and epoxy groups under mild conditions, enabling the directional introduction of PHFPO into target molecules. This is of great significance for the efficient and controllable preparation of PHFPO-based FP composite functional materials. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of existing modified graphene oxide, such as easy agglomeration, difficulty in uniform dispersion in the matrix, and low preparation efficiency, and to provide a fluoropolymer-modified monolayer graphene oxide that is highly dispersed in the matrix and does not easily agglomerate, as well as its preparation method.

[0009] To achieve the above objectives, the fluoropolymer-modified monolayer graphene oxide provided by the present invention is prepared by the following method: graphene oxide and a fluoropolymer are added to an organic solvent, and under ultrasonic assistance and nitrogen protection, the graphene oxide is exfoliated into a monolayer and reacted with the fluoropolymer. After exfoliation, the fluoropolymer and graphene oxide are allowed to continue reacting for 2-24 hours to obtain a fluoropolymer-modified monolayer graphene oxide dispersion. The dispersion is then filtered, washed, and dried to obtain fluoropolymer-modified monolayer graphene oxide.

[0010] The aforementioned fluoropolymers are perfluoroepoxy oligomer acyl halides or perfluoro anhydrides, which are mainly grafted onto the surface of graphene oxide through esterification reactions to form perfluoropolyether chains or perfluoroalkyl chains.

[0011] The general structural formula of the perfluoroepoxy oligomer acyl halide is R1-COX, where X is F or Cl, and R1 is...

[0012]

[0013] Where n is an integer from 1 to 14; when R1-COX is a hexafluoropropylene oxide trimer (n=3), the target product is labeled as (HFPO)3-GO, when R1-COX is a hexafluoropropylene oxide tetramer (n=4), the target product is labeled as (HFPO)4-GO, and so on.

[0014] The general structural formula of the above perfluoro anhydrides is R2-COOCO-R2, where R2 is...

[0015]

[0016] Where m is an integer from 1 to 7.

[0017] In the above method, the preferred ultrasonic temperature is 20–40°C and the ultrasonic time is 10–40 min.

[0018] In the above method, the preferred ratio of graphene oxide, fluoropolymer modifier, and organic solvent is 0.10-0.75 g: 0.01-0.10 L: 1 L.

[0019] In the above method, the preferred organic solvent is any one of anhydrous tetrahydrofuran, acetone, dichloromethane, 1,2-dichloroethane, N,N-dimethylformamide, N-methylpyrrolidone, and dimethyl sulfoxide.

[0020] In the above method, the solvent used for washing is any one or a combination of anhydrous tetrahydrofuran, acetone, anhydrous diethyl ether, N,N-dimethylformamide, and trichlorotrifluoroethane.

[0021] In the above method, the preferred drying temperature is 30–80°C, and this step can be carried out in a vacuum drying oven.

[0022] The beneficial effects of this invention are as follows:

[0023] 1. The preparation method of fluoropolymer-modified monolayer graphene oxide (GO) of this invention is simple, efficient, thorough, and under mild conditions, with controllable product structure (which can be controlled by the structure, chain length, and amount of the fluorinated modifier). The prepared two-dimensional nanocomposite material inherits the dual advantages of GO and fluoropolymers in terms of structure and performance. The fluorine content in the modified monolayer GO can reach 15%. After filtration, washing, and drying, the modified monolayer GO still maintains a good monolayer state. The dispersion can also be used directly for composite material preparation without drying. Experiments show that although the time for fluoropolymer-modified monolayer GO to maintain a highly dispersed state in solvents varies depending on the solvent, compared with unmodified GO, the types of organic solvents that can be used to disperse fluoropolymer-modified monolayer GO are significantly increased, and no sedimentation or stratification is observed after standing for 2 weeks in different organic solvents.

[0024] 2. This invention involves simultaneously exfoliating GO with an organic solvent under ultrasonic assistance and dispersing a fluoropolymer containing highly reactive end groups onto the GO surface. Subsequently, the acyl halide and other end groups of the fluoropolymer rapidly react with the hydroxyl, carboxyl, and epoxy groups on the GO surface, consuming these groups and grafting the fluorinated links of the fluoropolymer onto the surface of the monolayer GO. This approach weakens or even eliminates interlayer aggregation caused by hydrogen bonding in GO to a significant extent. Furthermore, due to the unique fluorine repulsion between the fluoropolymer chains grafted onto the GO surface, the GO, after initial grafting modification with the fluoropolymer, not only further promotes GO dispersion in organic solvents but also effectively inhibits re-aggregation between the modified monolayer GO layers. These advantages ensure that the modified GO prepared by this invention maintains an ideal monolayer in dispersants, matrices, and composite materials, thereby maximizing the dispersion performance of the modified GO. Its application in composite material design and preparation is expected to significantly improve the utilization rate of GO and the performance of the corresponding composite materials. Attached Figure Description

[0025] Figure 1 These are the infrared spectra of GO before modification and monolayer GO modified with fluoropolymer in Examples 1-3.

[0026] Figure 2 These are the elemental X-ray photoelectron spectroscopy (XPS) spectra of unmodified GO and fluoropolymer-modified monolayer GO in Examples 1-3.

[0027] Figure 3 This is the fine C1 s X-ray photoelectron spectrum of GO before modification.

[0028] Figure 4 This is the fine C1 s X-ray photoelectron spectroscopy spectrum of monolayer GO modified with fluoropolymer in Example 1.

[0029] Figure 5 These are X-ray diffraction patterns (5-40°) of GO before modification and of monolayer GO modified with fluoropolymers in Examples 1-3.

[0030] Figure 6 These are X-ray diffraction patterns (1-5°) of GO before modification and monolayer GO modified with fluoropolymers in Examples 1-3.

[0031] Figure 7 This is an atomic force microscope image of GO before modification.

[0032] Figure 8 This is a transmission electron microscope (TEM) image of the fluoropolymer-modified monolayer GO from Example 1.

[0033] Figure 9 This is an atomic force microscope image of the fluoropolymer-modified monolayer GO in Example 1.

[0034] Figure 10 This is a comparison chart of the dispersion stability of GO before modification and the fluoropolymer-modified monolayer GO in Example 1.

[0035] Figure 11 This is the fine C1 s X-ray photoelectron spectroscopy spectrum of monolayer GO modified with fluoropolymer in Example 2.

[0036] Figure 12 This is a transmission electron microscope (TEM) image of the fluoropolymer-modified monolayer GO from Example 2.

[0037] Figure 13 This is an atomic force microscope image of the fluoropolymer-modified monolayer GO in Example 2.

[0038] Figure 14 This is a comparison chart of the dispersion stability of GO before modification and the fluoropolymer-modified monolayer GO in Example 2.

[0039] Figure 15 This is the fine C1 s X-ray photoelectron spectroscopy spectrum of monolayer GO modified with fluoropolymer in Example 3.

[0040] Figure 16 This is a transmission electron microscope (TEM) image of the fluoropolymer-modified monolayer GO in Example 3.

[0041] Figure 17 This is an atomic force microscope image of the fluoropolymer-modified monolayer GO in Example 3.

[0042] Figure 18 This is a comparison chart of the dispersion stability of GO before modification and the fluoropolymer-modified monolayer GO in Example 3. Detailed Implementation

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to these embodiments.

[0044] Example 1

[0045] Taking the preparation of hexafluoropropylene oxide trimer-modified monolayer GO as an example, the specific preparation method is as follows:

[0046] At room temperature, 0.15 g of GO and 200 mL of N,N-dimethylformamide were added to a three-necked flask equipped with a condenser and a constant-pressure dropping funnel. Under nitrogen protection and ultrasonic assistance, 4.0 mL of hexafluoropropylene oxide trimer containing acyl fluoride end groups (CF3CF2CF2OCF(CF3)CF2OCF(CF3)COF, provided by Zhejiang Huanxin Fluorine Materials Co., Ltd.) was added dropwise to the three-necked flask over 20–40 min. Subsequently, the reaction was continued for 4 h at room temperature with stirring to obtain a dispersion. The dispersion was filtered, and the resulting solid was washed successively with trichlorotrifluoroethane and anhydrous acetone, and dried at 60 °C for 12 h to obtain a fluoropolymer-modified monolayer GO, denoted as (HFPO)3-GO.

[0047] The unmodified GO and the fluoropolymer-modified monolayer GO were characterized by infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and atomic force microscopy. The results are shown in the figure. Figures 1-10 .

[0048] Figure 1 Infrared spectroscopy results show that, after modification, it is located at 3447 cm⁻¹ -1 The broad and strong -OH stretching vibration of GO disappears upon absorption, and at the same time, the 1230 cm⁻¹ region... -1 The stretching vibrations of nearby CF were significantly enhanced. After modification, the characteristic peak of F1 s appeared at 688.6 eV in the X-ray photoelectron spectrum, while the characteristic peaks of various CFs also appeared in the C1 s peaks from 284.3 to 292.9 eV (comparison). Figure 2 and Figure 3 The above results demonstrate that the perfluoropolyether chain CF3CF2CF2OCF(CF3)CF2OCF(CF3)C(O)- of the hexafluoropropylene oxide trimer (HFPO)3 has been successfully grafted onto the GO surface. Furthermore, X-ray photoelectron spectroscopy revealed that the F content of the (HFPO)3-GO surface was 9.80% (see [link to X-ray photoelectron spectroscopy]). Figure 4 ).

[0049] Depend on Figure 5 and Figure 6The powder X-ray diffraction pattern shows that unmodified GO exhibits a sharp diffraction peak at 2θ = 11.2°, indicating a multilayer structure; while (HFPO)3-GO shows no diffraction peaks in the range of 2θ = 1°–40°, indicating that the originally ordered multilayer structure of GO has been completely transformed into a monolayer in the modified product (HFPO)3-GO, and it can still maintain its good monolayer state even after thorough drying. The monolayer structure of the target product is further confirmed by the characterization results of transmission electron microscopy and atomic force microscopy (compare with...). Figure 7 and Figure 8 , Figure 9 ).

[0050] A GO dispersion prepared by ultrasonic-assisted liquid-phase exfoliation using N,N-dimethylformamide as a dispersant was allowed to stand together with a (HFPO)3-GO dispersion. It was found that the unmodified GO dispersion precipitated significantly within 2 days, while the (HFPO)3-GO dispersion showed no precipitation even after 2 weeks of standing (see...). Figure 10 This demonstrates that (HFPO)3-GO can always maintain an ideal dispersion state in the dispersant.

[0051] Example 2

[0052] In this embodiment, an equal volume of hexafluoropropylene oxide tetramer containing acyl fluoride end groups (CF3CF2CF2O(CF(CF3)CF2O)2CF(CF3)COF, provided by Zhejiang Huanxin Fluorine Materials Co., Ltd.) containing acyl fluoride end groups was used to replace the hexafluoropropylene oxide trimer containing acyl fluoride end groups in Example 1. The reaction time was extended from 4 h to 6 h, and the organic solvent was changed from N,N-dimethylformamide to acetone. Other steps were the same as in Example 1, and a fluoropolymer-modified monolayer GO was obtained, denoted as (HFPO)4-GO.

[0053] Figure 1 infrared spectrum and Figure 11 The X-ray photoelectron spectroscopy characterization results were similar to those in Example 1, both demonstrating that the perfluoropolyether chain CF3CF2CF2O(CF(CF3)CF2O)2CF(CF3)C(O)- of the hexafluoropropylene oxide tetramer (HFPO)4 had been successfully grafted onto the GO surface. Furthermore, the F content of the (HFPO)4-GO surface was measured to be 10.26% using X-ray photoelectron spectroscopy.

[0054] Depend on Figure 5 and Figure 6 Powder X-ray diffraction results Figure 12 and Figure 13 The transmission electron microscopy and atomic force microscopy characterization results were similar to those in Example 1, indicating that (HFPO)4-GO had completely become a monolayer and could still maintain its good monolayer state even after thorough drying.

[0055] GO dispersions obtained by ultrasonic-assisted liquid-phase exfoliation using acetone as a dispersant were allowed to stand together with (HFPO)4-GO dispersions. It was found that the unmodified GO dispersions precipitated significantly in less than one day, while the (HFPO)4-GO dispersions showed no precipitation even after two weeks of standing (see...). Figure 14 This demonstrates that (HFPO)4-GO can always maintain an ideal dispersion state in the dispersant.

[0056] Example 3

[0057] In this embodiment, an equal volume of hexafluoropropylene oxide pentadecimer (CF3CF2CF2O(CF(CF3)CF2O)) containing acyl chloride end groups was used. 13 The hexafluoropropylene oxide trimer containing acyl fluoride end groups in Example 1 was replaced with CF(CF3)COCl. The reaction time was extended from 4 h to 24 h, the reaction temperature was 40 °C, and the organic solvent was changed from N,N-dimethylformamide to N-methylpyrrolidone. The other steps were the same as in Example 1, and a fluoropolymer-modified monolayer GO was obtained, denoted as (HFPO). 15 -GO.

[0058] Figure 1 infrared spectrum and Figure 15 The X-ray photoelectron spectroscopy characterization results were similar to those in Example 1, both confirming that the perfluoropolyether chain CF3CF2CF2O(CF(CF3)CF2O) of the hexafluoropropylene oxide pentadecimer was a CF3CF2CF2O. 13 CF(CF3)C(O)- has been successfully grafted onto the GO surface. Furthermore, X-ray photoelectron spectroscopy (HFPO) was used to measure... 15 The F content on the GO surface is 14.66%.

[0059] Depend on Figure 5 and Figure 6 Powder X-ray diffraction results Figure 16 and Figure 17 The transmission electron microscopy and atomic force microscopy characterization results were similar to those in Example 1, indicating that (HFPO) 15 -GO has become completely monolayered and can maintain its good monolayer state even after being fully dried.

[0060] A GO dispersion prepared by ultrasonic-assisted liquid-phase exfoliation using N-methylpyrrolidone as a dispersant was reacted with (HFPO). 15 The GO dispersion was left to stand together. It was found that the unmodified GO mixture settled significantly in less than one day, while (HFPO)... 15 The mixture of -GO showed no sedimentation even after standing for two weeks (see...). Figure 18 Proof (HFPO) 15-GO can always maintain an ideal dispersion state in dispersants.

[0061] The method for synthesizing the hexafluoropropylene oxide pentadecimer containing acyl chloride terminal groups in this embodiment is as follows: under nitrogen protection and room temperature conditions, 5.0 g of hexafluoropropylene oxide pentadecimer (CF3CF2CF2O(CF(CF3)CF2O)) containing carboxylic acid terminal groups was prepared. 13 CF(CF3)COOH (provided by DuPont) was added dropwise to 15 mL of thionyl chloride and refluxed at 80 °C for 8 h under stirring. The remaining thionyl chloride was removed by vacuum distillation to obtain a hexafluoropropylene oxide pentadecimer containing acyl chloride end groups.

[0062] Example 4

[0063] In this embodiment, an equal volume of pentafluoropropionic anhydride (CF3CF2COOCOCF2CF3, provided by Shanghai Maclean Biochemical Technology Co., Ltd.) was used to replace the hexafluoropropylene oxide trimer containing acyl fluoride end groups in Example 1. The reaction time was extended from 4 h to 5 h. Other steps were the same as in Example 1, and a fluoropolymer-modified monolayer GO was obtained, denoted as PFPA-GO.

[0064] Example 5

[0065] In this embodiment, an equal volume of nonafluoropentanoic anhydride (CF3(CF2)3COOCO(CF2)3CF3, provided by Beijing Vande Biotechnology Co., Ltd.) was used to replace the hexafluoropropylene oxide trimer containing acyl fluoride end groups in Example 1. The reaction time was extended from 4 h to 8 h, the reaction temperature was 40 °C, and the organic solvent was changed from N,N-dimethylformamide to N-methylpyrrolidone. Other steps were the same as in Example 1, resulting in a fluoropolymer-modified monolayer GO, denoted as NFPA-GO.

Claims

1. A method for preparing fluoropolymer-modified monolayer graphene oxide, characterized in that: Graphene oxide and fluoropolymers are added to an organic solvent. Under ultrasonic assistance and nitrogen protection, the graphene oxide is exfoliated into a single layer and reacted with the fluoropolymer. After exfoliation, the fluoropolymer and graphene oxide are allowed to continue reacting for 2–24 h to obtain a dispersion of fluoropolymer-modified single-layer graphene oxide. The dispersion is then filtered, washed, and dried to obtain fluoropolymer-modified single-layer graphene oxide. The fluoropolymer is a perfluoroepoxy oligomer acyl halide or a perfluoro anhydride. The general structural formula of the perfluoroepoxy oligomer acyl halide is R1-COX, where X is F or Cl, and R1 is... Where n is an integer from 1 to 14; The general structural formula of the perfluoro anhydride is R2-COOCO-R2, where R2 is... Where m is an integer from 1 to 7; The temperature of the ultrasound is 20-40°C. o C, ultrasound time is 10–40 min; The ratio of graphene oxide, fluoropolymer, and organic solvent is 0.10–0.75 g: 0.01–0.10 L: 1 L.

2. The method for preparing fluoropolymer-modified monolayer graphene oxide according to claim 1, characterized in that: The organic solvent is any one of anhydrous tetrahydrofuran, acetone, dichloromethane, 1,2-dichloroethane, N,N-dimethylformamide, N-methylpyrrolidone, and dimethyl sulfoxide.

3. The method for preparing fluoropolymer-modified monolayer graphene oxide according to claim 1, characterized in that: The solvent used for washing is any one or a combination of anhydrous tetrahydrofuran, acetone, anhydrous diethyl ether, N,N-dimethylformamide, and trichlorotrifluoroethane.

4. The method for preparing fluoropolymer-modified monolayer graphene oxide according to claim 1, characterized in that: The drying temperature is 30-80°C. o C.

5. Fluoropolymer-modified monolayer graphene oxide prepared by any one of claims 1 to 4.

Images