Method for grafting anionic copolymer on surface of metal material through surface-initiated polymerization

Abstract

The invention belongs to the technical field of metal material surface modification, and particularly relates to a method for grafting an anionic copolymer on the surface of a metal material through surface-initiated polymerization. A surface-initiated polymerization technology is adopted, firstly, an initiator is anchored to the surface of a metal material, then an anionic monomer and a comonomer are added, and the anionic copolymer modified metal material is prepared through a surface thermal / photo-initiated polymerization reaction. The method has the advantages of being easy and convenient to operate, mild in reaction condition and the like, the polymer layer grafted on the surface of the metal material through the method is stable and uniform, the chemical structure is easy to adjust, and therefore the application prospect of the polymer layer in the fields of medical instruments, electronic energy, aerospace and the like is widened.

Description

Technical Field

[0001] The present invention belongs to the technical field of surface modification of metal materials, and particularly relates to a method for grafting an anionic copolymer on the surface of a metal material through surface-initiated polymerization. Background Art

[0002] The technology of metal material surface modification plays a crucial role in many fields such as aerospace, marine navigation, advanced equipment manufacturing, nuclear energy and hydrogen energy, new energy, and biomedical metals. The application of polymer coatings in metal surface modification is very extensive. By endowing the metal surface with various excellent functions, it can enable the metal to adapt to various complex working environments and meet the high requirements for material properties in different fields. By introducing specific groups, such as fluorine-containing groups or anionic groups, into the polymer structure through copolymerization, characteristics such as high (electro)chemical stability, high thermal stability, and good hydrophilicity can be obtained. These characteristics have attracted much attention for polymer coatings in the field of metal surface modification (Mater. Today: Proc. 2024, https: / / doi.org / 10.1016 / j.matpr.2024.09.001.).

[0003] However, there is a lack of sufficient physical or chemical interaction between traditional polymer coatings and the metal surface, resulting in low bonding strength between the coating and the metal surface. Existing methods for improving the bonding strength between polymers and metal surfaces include surface radiation modification, chemical corrosion modification, and corona modification, etc. These methods still have certain limitations. For example, the modification process is complex, the cost is high, and it is easy to damage the metal substrate and the polymer coating (Prog. Org. Coat. 2020, 148, 105847.).

[0004] Therefore, it is an urgent problem to be solved at present to develop a metal surface modification method with simple operation, easy adjustment of metal surface properties, and close bonding between the polymer and the metal surface. Summary of the Invention

[0005] In view of this, aiming at the problems existing in the prior art, the present invention provides a method for grafting an anionic copolymer on the surface of a metal material through surface-initiated polymerization.

[0006] In recent years, researchers have successfully grafted polymers with controllable thickness, chemical composition, grafting density, uniform distribution, and flat surface onto various substrate surfaces through surface-initiated polymerization (Angew. Chem. Int. Ed. 2023, 62, e202219312.). This new surface modification method has broad application prospects in the fields of micro / nano processing, microelectronic devices, biomaterials, energy devices, etc. Based on this, in the present invention, an anionic copolymer is firmly grafted onto the surface of a metal material by means of surface-initiated polymerization through chemical bonding or interaction, so as to improve the adhesion between the polymer and the metal material surface, and prevent the cracking and peeling of the metal surface-modified polymer layer during use, thereby extending the service life of the metal material. In addition, by changing the copolymer structure, different properties can be imparted to the metal surface, such as hydrophilicity / hydrophobicity, mechanical stability, electrochemical stability, etc.

[0007] It should be noted that the method of the present invention is applicable to a variety of metals and their alloys (such as aluminum, copper, stainless steel, etc.), and the initiation and polymerization conditions can be optimized for specific metal surfaces, with strong flexibility. By selecting different monomers or polymerization conditions, the thickness, chemical composition, and functional characteristics of the grafted layer, such as hydrophobicity, hydrophilicity, biocompatibility, or electrical properties, can be precisely controlled to meet different application requirements.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] The first technical object of the present invention is to provide a method for anchoring an initiator on the surface of a metal material, and the specific technical solution is as follows:

[0010] Method 1: Immerse the metal material in an ultradry solvent containing an initiator, where the concentration of the initiator is 0.1 - 10.0 g / L. After standing in the dark for 12 - 72 hours, take out the metal material and rinse it thoroughly with the ultradry solvent. Then place the metal material in a vacuum drying oven at 60 - 100 °C and dry it for 12 - 48 hours to obtain the metal material anchored with the initiator (1 - 100 cm 2 );

[0011] Method 2: Hydroxylate the surface of the metal material, and then immerse it in an ultradry solvent containing an initiator to allow the initiator to react with the hydroxyl groups on the metal material surface. The concentration of the initiator is 0.1 - 10.0 g / L, the reaction time is 12 - 72 hours, and the reaction temperature is 25 - 60 °C. After the reaction is completed, take out the metal material and rinse it thoroughly with the ultradry solvent. Then place the metal material in a vacuum drying oven at 60 - 100 °C and dry it for 12 - 48 hours to obtain the metal material anchored with the initiator (1 - 100 cm 2 );

[0012] Preferably, the initiator used in Method 1 can be directly anchored on the surface of the metal material, and the initiator has the structures of Formula (1) and Formula (2):

[0013]

[0014] Among them, R 2 is an alkane chain with 0 to 10 carbon units; R 3 is an ester group or an amide group; R 4 , R 5 are a hydrogen atom, a fluorine atom or a methyl group; X is a bromine or iodine atom; R 6 is an ester group or an amide group; R 7 , R 8 are a hydrogen atom, an alkyl group with 1 to 15 carbon atoms, an aryl group; R 9 is an aliphatic group with 1 to 15 carbon atoms, an alkyl mercapto group with 1 to 15 carbon atoms, an alkoxy group with 1 to 15 carbon atoms, an aromatic group, an aryl mercapto group, an aryloxy group, a dialkylamino group with 1 to 15 carbon atoms, a diarylamino group; R 10 is an ester group or an amide group; R 11 is a methyl group or isopentane; R 12 is a cyano group or a dimethyl butyrate group; R 13 is an isobutyronitrile group, an isoheptanenitrile group, a dimethyl isobutyrate group.

[0015] Preferably, the initiator used in Method 2 can be anchored on the surface of the hydroxylated metal material, and the initiator has the structures of Formula (3) and (4):

[0016]

[0017] Among them, R 2 is an alkane chain with 0 to 10 carbon units; R 3 is an ester group or an amide group; R 4 , R 5 are a hydrogen atom, a fluorine atom or a methyl group; X is a bromine or iodine atom; R 6 is an ester group or an amide group; R 7 , R 8 are a hydrogen atom, an alkyl group with 1 to 15 carbon atoms, an aryl group; R 9 is an aliphatic group with 1 to 15 carbon atoms, an alkyl mercapto group with 1 to 15 carbon atoms, an alkoxy group with 1 to 15 carbon atoms, an aromatic group, an aryl mercapto group, an aryloxy group, a dialkylamino group with 1 to 15 carbon atoms, a diarylamino group; R 10 is an ester group or an amide group; R 11 is a methyl group or isopentane; R 12 is a cyano group or a dimethyl butyrate group; R 13 is an isobutyronitrile group, an isoheptanenitrile group, a dimethyl isobutyrate group. R14 ,R 15 ,R 16 is a chlorine atom, a hydroxyl group, a methyl group, a methoxy group, or an ethoxy group.

[0018] Preferably, the metal material includes iron, chromium, manganese, nickel, gold, silver, copper, lithium, sodium, potassium, indium, titanium, palladium, aluminum, and their alloys.

[0019] The second technical object of the present invention is to provide a method for grafting an anionic copolymer onto the surface of a metal material through surface-initiated polymerization, including the preparation of a reaction solution, surface-initiated polymerization, and post-treatment. The specific technical solution is as follows:

[0020] (1) Preparation of the reaction solution:

[0021] Preparation of the reaction solution for non-gaseous monomers: The reactants include an anionic monomer, a comonomer, and a reaction additive, and the molar ratio of the anionic monomer to the comonomer is 1.0:(0.1 - 10.0), and the molar ratio of the anionic monomer to the reaction additive is 1.0:(0.001 - 0.5); Dissolve the reactants in a solvent, remove the oxygen in the reaction system, and store it away from light as the reaction solution for surface-initiated polymerization.

[0022] Preparation of the reaction solution for gaseous monomers: Inject the solvent and the reaction additive into the reaction kettle under a nitrogen atmosphere, and slowly charge the gaseous monomer into the reaction kettle at -40°C; The reactants include an anionic monomer, a comonomer, and a reaction additive, and the molar ratio of the anionic monomer to the comonomer is 1.0:(0.1 - 10.0), and the molar ratio of the anionic monomer to the reaction additive is 1.0:(0.001 - 0.5); Dissolve the reactants in a solvent, remove the oxygen in the reaction system, and store it away from light as the reaction solution for surface-initiated radical polymerization.

[0023] (2) Surface-initiated polymerization and post-treatment:

[0024] Uniformly coat the reaction solution prepared in step (1) onto the surface of the metal material anchored with the initiator as described in claim 1 (1 - 100 cm 2 ), and carry out the reaction under heating or light conditions; After the reaction is completed, take out the metal material and rinse it thoroughly with an ultra-dry solvent to remove the reaction solution attached to the surface of the metal material; Dry the cleaned metal material in a vacuum drying oven at 60 - 100°C for 12 - 48 hours to obtain the metal material modified with the anionic copolymer.

[0025] Preferably, in the preparation of the reaction solution, the anionic monomer has the structure of formula (5):

[0026]

[0027] Among them, R 1 , R 2 , R 3 is a fluorine atom, trifluoromethyl group or a perfluoroalkane chain with 2 to 5 carbon units; R 4 is a methylene group, oxygen atom, ester group or carbonyl group; R 3 is an ester group or amide group; R 5 is a perfluoroether chain with 1 to 10 carbon units or an alkane chain with 0 to 3 carbon units; R 7 is a carbonyl group, sulfonyl group, an alkane chain with 0 to 2 carbon units; R 8 is trifluoromethyl group, methyl group, ethyl group, n-propyl group, isopropyl group, phenyl group, p-trifluoromethylphenyl group, p-methoxyphenyl group or biphenyl group; R 9 is trifluoromethyl group, methyl group, ethyl group or a perfluoroether chain with 1 to 10 carbon units.

[0028] Preferably, when preparing the reaction solution of the non-gaseous monomer, the comonomers used include one or more of trifluoroethyl methacrylate, trifluoroethyl acrylate, hexafluoroisopropyl methacrylate, hexafluorobutyl acrylate, pentafluoropropyl methacrylate, hexafluorobutyl methacrylate, heptafluorobutyl methacrylate, heptafluorobutyl acrylate, octafluoropentyl methacrylate, dodecafluoroheptyl methacrylate, perfluorooctyl methacrylate, perfluoroundecyl methacrylate, (perfluorocyclohexyl) methacrylate, pentafluorostyrene, perfluoroethyl vinyl ether, perfluoropropyl vinyl ether, 2-(heptafluoropropoxy) hexafluoropropyl trifluorovinyl ether, perfluoro(3-oxapent-4-ene) sulfonyl fluoride, perfluoro(4-methyl-3,6-dioxaoct-7-ene) sulfonyl fluoride, (meth)acrylate derivatives, acrylate derivatives, vinyl ether derivatives, vinyl acetate derivatives, acrylamide derivatives, N-vinylpyrrolidone derivatives, N-vinylcaprolactam derivatives, styrene derivatives.

[0029] Preferably, when preparing the reaction solution of the gaseous monomer, the comonomers used include one or more of tetrafluoroethylene, vinylidene fluoride, trichlorotrifluoroethylene, hexafluoropropene, ethylene, propylene, vinyl ether derivatives, vinyl acetate derivatives, N-vinylpyrrolidone derivatives, N-vinylcaprolactam derivatives.

[0030] Preferably, in the method for preparing the reaction solution, the reaction additive used is one of azo compounds, peroxides, dithiocarbonates, trithiocarbonates, xanthates, dithiocarbamates, perfluoroalkyl halides, and alkyl halides; one or a combination of porphyrin compounds, dihydro-phenazine, phenothiazine, and phenoxazine; and the solvent used is one or a combination of dimethyl sulfoxide, N,N-dimethylformamide, carbonates, N-methylpyrrolidone, acetonitrile, ethyl acetate, and acetone.

[0031] Preferably, in the surface-initiated polymerization and post-treatment method, when the reaction condition is heating, the heating temperature is 40 - 120 °C, and the reaction time is 1 - 72 hours; when the reaction condition is light irradiation, a light source with an emission wavelength of 250 - 700 nm is used, and the reaction time is 1 - 36 hours.

[0032] Compared with the prior art, the present invention has the following excellent effects:

[0033] 1) The present invention discloses a method for grafting an anionic copolymer on the surface of a metal material through surface-initiated polymerization. This method is simple to operate and has mild reaction conditions; the grafted polymer prepared by this method is connected to the metal surface through chemical bonds or strong interactions, significantly enhancing the binding force between the polymer and the metal and avoiding the problem of easy detachment in the physical adsorption method. This strong binding force makes the polymer have higher stability under harsh conditions.

[0034] 2) The method disclosed in the present invention is applicable to a variety of metals and their alloys (such as aluminum, copper, stainless steel, etc.), and the initiation and polymerization conditions can be optimized for specific metal surfaces, with strong flexibility; by selecting different monomers or polymerization conditions, the thickness, chemical composition, and functional properties of the grafted layer, such as hydrophobicity, hydrophilicity, biocompatibility, or electrical properties, can be precisely controlled to meet different application requirements; this method shows broad application prospects in the fields of anti-corrosion, medical devices, biosensors, intelligent coatings, energy storage, and catalysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention and the technical solutions, the following will briefly introduce the drawings required for use in the embodiments of the present invention or the prior art solutions. Obviously, the drawings in the following description are only a part of the embodiments of the present invention, and other drawings can also be obtained according to the provided drawings.

[0036] Figure 1 It is the synthesis route of mercapto-pyrrole dithiocarbamate in Example 1.

[0037] Figure 2 It is the synthesis route of catechol xanthate in Example 2.

[0038] Figure 3 It is the synthesis route of catechol-based bromotetrafluoroacetone in Example 3.

[0039] Figure 4 It is the synthesis route for preparing anionic copolymer-modified stainless steel by surface thermal-initiated polymerization in Example 4.

[0040] Figure 5 It is the synthesis route for preparing anionic copolymer-modified copper by surface photo-initiated polymerization in Example 5.

[0041] Figure 6 It is the XPS diagram of anionic copolymer-modified stainless steel in Example 4.

[0042] Figure 7 It is the SEM and EDS diagrams of anionic copolymer-modified copper in Example 5.

[0043] Figure 8 It is the gel permeation chromatography elution time curve of the polymer peeled off from the stainless steel surface in Example 4.

[0044] Figure 9 It is the water contact angle test result of anionic copolymer-modified stainless steel surface in Application Example 4.

[0045] Figure 10 It is the surface modulus test result of anionic copolymer-modified stainless steel surface in Application Example 4.

[0046] Figure 11 It is the electrochemical impedance test result of anionic copolymer-modified copper in Application Example 5.

[0047] Figure 12 It is the synthesis schematic diagram of grafting anionic copolymer on the surface of metal materials by surface-initiated polymerization in the present invention. Detailed implementation manners

[0048] Next, the technical solutions in the embodiments of the present invention will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0049] The special term "embodiment" here, any embodiment described as "exemplary" does not have to be construed as superior to or better than other embodiments. For the performance index tests in the embodiments of this application, unless otherwise specified, conventional test methods in the art are adopted. It should be understood that the terms described in this application are only used to describe specific implementation manners and are not used to limit the content disclosed in this application.

[0050] Unless otherwise specified, the technical and scientific terms used in this application have the same meanings as those commonly understood by those of ordinary skill in the technical field to which this application belongs; other test methods and technical means not specifically noted in this application refer to the test methods and technical means commonly used by those of ordinary skill in the art.

[0051] To better illustrate the content of this application, numerous specific details are given in the following specific embodiments. Those skilled in the art should understand that this application can still be implemented without certain specific details. In the embodiments, some methods, means, instruments, devices, etc. well-known to those skilled in the art are not described in detail in order to highlight the gist of this application.

[0052] On the premise of no conflict, the technical features disclosed in the embodiments of this application can be combined arbitrarily, and the obtained technical solutions belong to the content disclosed in the embodiments of this application.

[0053] The present invention realizes grafting an anionic copolymer on the surface of a metal material through surface thermal / photoinitiated polymerization. By selecting different monomers or polymerization conditions, the thickness, chemical composition, and functional characteristics of the grafted layer, such as hydrophobicity, corrosion resistance, etc., can be precisely controlled.

[0054] For those skilled in the art, some non-essential improvements and adjustments made based on the above-mentioned invention content are also considered to fall within the protection scope of the present invention.

[0055] Part 1: Synthesis of the initiator required for surface-initiated polymerization

[0056] Example 1

[0057] Sodium hydride (NaH, 0.48 g, 20.0 mmol) and N,N-dimethylformamide solvent (20 mL) were added to a round-bottom flask equipped with a magnetic stir bar. Subsequently, pyrrole (1.34 g, 20.0 mmol) was slowly added dropwise under stirring. After the reaction mixture was stirred at room temperature for 1 hour, carbon disulfide (1.52 g, 20.0 mmol) was slowly added dropwise to the reaction mixture, and the reaction continued at room temperature for 1 hour. Subsequently, 4-(chloromethyl)phenylacetic acid (3.68 g, 20.0 mmol), N-hydroxysuccinimide (2.32 g, 20.0 mmol), and N,N'-diisopropylcarbodiimide (500.1 mg, 4.0 mmol) were added to the reaction mixture, and the reaction mixture was stirred at room temperature until the N-hydroxysuccinimide was completely reacted. Mercaptoethylamine (1.54 g, 20.0 mmol) and triethylamine (2.02 g, 20.0 mmol) were dissolved in N,N-dimethylformamide solvent and slowly added dropwise to the above reaction mixture. The reaction mixture was stirred at room temperature for 24 hours. After the reaction was completed, the mixture was extracted three times with dichloromethane (50 mL), washed three times with saturated NaCl solution (50 mL), then dried over anhydrous magnesium sulfate. After filtering the mixture, the filtrate was concentrated under reduced pressure. After separation by silica gel column chromatography, a yellow powdery mercaptopyrrole thiocarbamate initiator for surface anchoring was obtained.

[0058] Figure 1 It is the synthetic route of mercaptopyrrole thiocarbamate in Example 1.

[0059] Example 2

[0060] Aluminum trichloride (8.01 g, 60.0 mmol) and dichloromethane solution (15 mL) were added to a round-bottom flask equipped with a magnetic stir bar. Under stirring, a dichloromethane solution (15 mL) dissolving 1,2-benzenediol (2.20 g, 20.0 mmol) was slowly added dropwise to the above solution, and the mixture was stirred at room temperature for 1 hour. Subsequently, 2-bromohexanoyl bromide (5.16 g, 20.0 mmol) was slowly added dropwise to the above reaction mixture, and the mixture was stirred at room temperature for 6 hours. After the reaction was completed, the reaction mixture was treated with ice water and extracted three times with ethyl acetate (50 mL). Then it was dried over anhydrous magnesium sulfate. After filtering the mixture, the filtrate was concentrated under reduced pressure. After separation by silica gel column chromatography, a white powdery catechol-based bromohexanone was obtained. Subsequently, the catechol-based bromohexanone was dissolved in tetrahydrofuran solution, and a tetrahydrofuran solution of sodium ethyl xanthate (2.88 g, 20.0 mmol) was slowly added dropwise to the above solution, and the mixture was stirred at room temperature overnight. After the reaction was completed, the mixture was extracted three times with dichloromethane (50 mL), washed three times with saturated NaCl solution (50 mL), then dried over anhydrous magnesium sulfate. After filtering the mixture, the filtrate was concentrated under reduced pressure. After separation by silica gel column chromatography, a white powdery catechol-based xanthate initiator for surface anchoring was obtained.

[0061] Figure 2 It is the synthetic route of catechol-based xanthate in Example 2.

[0062] Example 3

[0063] Add aluminum trichloride (8.01 g, 60.0 mmol) and dichloromethane solution (15 mL) into a round-bottom flask equipped with a stir bar. While stirring, slowly drip the dichloromethane solution (15 mL) dissolved with 1,2-benzenediol (2.20 g, 20.0 mmol) into the above solution, and stir at room temperature for 1 hour. Subsequently, slowly drip bromotetrafluoropropionyl bromide (5.74 g, 20.0 mmol) into the above reaction solution, and stir at room temperature for 8 hours. After the reaction is completed, treat the reaction solution with ice water, extract it three times with ethyl acetate (50 mL), then dry it with anhydrous magnesium sulfate, filter the mixture, and perform vacuum concentration on the filtrate. After separation by silica gel column chromatography, a catechol-based bromotetrafluoroacetone initiator for surface anchoring is obtained.

[0064] Figure 3 It is the synthetic route of catechol-based bromotetrafluoroacetone in Example 3.

[0065] Second part: Grafting an anionic copolymer on the surface of a metal material by surface-initiated polymerization method

[0066] Example 4

[0067] Heat to prepare a stainless steel material modified with poly(perfluoroundecyl methacrylate-co-poly(ethylene glycol) methacrylate-co-sodium acrylate) copolymer:

[0068] 1. Prepare a stainless steel material with surface-anchored initiator: Immerse the stainless steel in an anhydrous tetrahydrofuran solvent containing a mercaptopyrrolidine dithiocarbamate initiator (synthesis method see Example 1), where the concentration of the initiator is 2.0 g / L. After standing for 48 hours under dark conditions, take out the stainless steel and rinse it thoroughly with anhydrous tetrahydrofuran solvent. Then place the stainless steel in a vacuum drying oven at 60 °C and dry it for 48 hours to obtain a stainless steel material with the initiator anchored.

[0069] 2. According to Reaction Solution Preparation Method 1, perfluoroundecyl methacrylate: poly(ethylene glycol) methacrylate: sodium acrylate were dissolved in anhydrous acetonitrile at a molar ratio of 1:1:1, where the amount of perfluoroundecyl methacrylate was 1.0 mmol. A reaction solution was prepared at a molar ratio of perfluoroundecyl methacrylate: azobisisobutyronitrile = 100:1 and subjected to degassing and deoxygenation treatment. Subsequently, the prepared reaction solution was evenly coated on the surface of the stainless-steel material obtained in the first step and reacted at 70 °C for 48 h. After the reaction, the stainless-steel was taken out and rinsed three times with anhydrous tetrahydrofuran. Subsequently, the metal aluminum was transferred to a vacuum drying oven at 70 °C and dried for 72 hours to obtain a stainless-steel material modified with an anionic copolymer.

[0070] The stainless-steel material modified with anionic copolymer was immersed in a NaOH alkaline solution to strip the anionic copolymer grafted on the surface of the stainless-steel. The soaked solution was collected, extracted with ethyl acetate, and the solvent was removed by rotary evaporation to obtain a slightly yellow solid. The molecular weight of the polymer measured by GPC was 4.2×10 4 g / mol.

[0071] Figure 4 It is the synthetic route of the stainless-steel material modified with the anionic copolymer synthesized in Example 4. Figure 8 It is the gel permeation chromatography elution time curve of the polymer stripped from the surface of the stainless-steel.

[0072] Example 5

[0073] Preparation of a copper material modified with poly(lithium hexenoate-co-perfluoropropyl vinyl ether-co-N-vinylpiperidone-co-chlorotrifluoroethylene) copolymer by light irradiation:

[0074] 1. Preparation of a copper material with an anchored initiator on the surface: Copper was immersed in an anhydrous tetrahydrofuran solvent containing a catechol-based xanthate initiator (synthesis method see Example 2), where the concentration of the initiator was 2.0 g / L. After standing in the dark for 48 hours, the copper was taken out and rinsed thoroughly with anhydrous tetrahydrofuran solvent. Subsequently, the copper was placed in a vacuum drying oven at 60 °C and dried for 48 hours to obtain a copper material with the initiator anchored.

[0075] 2. According to Reaction Solution Preparation Method 2, dissolve lithium hexenoate, perfluoropropyl vinyl ether, N-vinylpiperidone, and chlorotrifluoroethylene in diethyl carbonate anhydrous in a molar ratio of 1:1:1:1, where perfluoroundecyl methacrylate is 1.0 mmol. Prepare the reaction solution according to a molar ratio of perfluoroundecyl methacrylate: reaction additive (phenothiazine) = 100:1 and conduct degassing and deoxygenation treatment. Subsequently, evenly coat the prepared reaction solution onto the surface of the copper material obtained in the first step and react under blue light irradiation for 48 h. After the reaction, take out the copper and rinse it three times with anhydrous tetrahydrofuran. Then transfer the metallic copper to a vacuum drying oven at 70 °C and dry it for 72 hours to obtain a metallic copper material modified with an anionic copolymer.

[0076] Immerse the metallic copper material modified with the anionic copolymer in a NaOH alkaline solution to strip the anionic copolymer grafted on the copper surface. Collect the soaked solution, extract it with ethyl acetate, and remove the solvent by rotary evaporation to obtain a slightly yellow solid. The molecular weight of the polymer measured by GPC is 5.0×10 4 g / mol.

[0077] Figure 5 Synthesis route of the copper material modified with the anionic copolymer synthesized in Example 5.

[0078] Example 6

[0079] Combine the copper material modified with the anionic copolymer obtained in Example 5 with a lithium metal electrode plate to form a counter electrode and assemble it into a button battery. The electrolyte used in the battery is a mixed solution of ethylene glycol dimethyl ether (1.0 vol%), 1,3-epoxypentacyclo (1.0 vol%), lithium nitrate (0.05 vol%), lithium bis(trifluoromethanesulfonyl)imide (1.0 mol / L), and lithium bis(fluorosulfonyl)imide (0.1 mol / L).

[0080] Part Three: Structural Characterization and Performance Analysis of the Metallic Material Modified with the Anionic Copolymer

[0081] Application Example 1

[0082] The XPS analysis was carried out on the stainless steel material modified with the anionic copolymer prepared in Example 4. After thoroughly cleaning the surface of the stainless steel material, it was still possible to detect the signal peaks of CF3 (293 eV, C 1s), CF2 (291 eV, C 1s), the signal peak of C=O bond (288 eV, C 1s), the signal peak of C-O bond (286 eV, C 1s), and the signal peak of C-C bond (284 eV, C 1s), indicating that the anionic copolymer was successfully grafted onto the stainless steel material by the method of surface-initiated polymerization. The SEM and EDS analyses were carried out on the copper metal modified with the anionic copolymer prepared in Example 5. The copper metal modified with the anionic copolymer had a flat surface, and the elements C, F, O, and N were evenly distributed.

[0083] Figure 6 XPS diagram of the anionic copolymer modified stainless steel in Example 4. Figure 7 SEM and EDS diagrams of the anionic copolymer modified copper in Example 5.

[0084] Application Example 2

[0085] The surface water contact angle of the stainless steel material modified with the anionic copolymer prepared in Example 4 was tested. Compared with the unmodified stainless steel material, the stainless steel material modified with the anionic copolymer had a smaller water contact angle (102.8° vs. 91.0°), indicating that this method could prepare stainless steel materials with hydrophilic properties. In addition, the anionic copolymer grafted on the surface of the stainless steel material obtained by AFM testing had a relatively high Young's modulus (2.7 GPa), and these properties improved its application prospects in industries such as industry and ocean.

[0086] Figure 9 Water contact angle test results of the anionic copolymer modified stainless steel surface in Application Example 4. Figure 10 Modulus test results of the anionic copolymer modified stainless steel surface in Application Example 4.

[0087] Application Example 3

[0088] The copper metal material modified with the anionic copolymer obtained in Example 5 was combined with a lithium metal electrode plate to form a counter electrode and assembled into a button battery. At room temperature, its electrochemical impedance was tested by an electrochemical workstation CHI660E, as Figure 11 .

[0089] Compared with the unmodified copper metal material, the anion copolymer-modified copper metal material has a lower interfacial resistance (66 Ω vs. 153 Ω), indicating that grafting the anion copolymer on the copper metal surface can accelerate the ion conduction at the interface. Therefore, the interfacial resistance of the battery is effectively reduced, demonstrating its application prospect in the energy field.

[0090] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for anchoring an initiator on the surface of a metal material, characterized in that: Including method 1 or method 2, the steps are as follows: Method 1: Soak the metal material in an ultra-dry solvent containing an initiator, wherein the concentration of the initiator is 0.1 to 10.0 g / L, and place it in a dark place for 12 to 72 hours. Then, take out the metal material and rinse it thoroughly with the ultra-dry solvent. Then, dry the metal material in a vacuum drying oven at 60 to 100°C for 12 to 48 hours to obtain an initiator-anchored metal material (1 to 100 cm 2 ); Method 2: Surface hydroxylation treatment is performed on the metal material, and then the metal material is immersed in an ultra-dry solvent containing an initiator, so that the initiator reacts with the hydroxyl groups on the surface of the metal material; the concentration of the initiator is 0.1 to 10.0 g / L, the reaction time is 12 to 72 hours, and the reaction temperature is 25 to 60° C. After the reaction is completed, the metal material is taken out and fully rinsed with the ultra-dry solvent, and then the metal material is placed in a vacuum drying oven at 60 to 100° C. and dried for 12 to 48 hours to obtain an initiator-anchored metal material (1 to 100 cm 2 ).

2. The method for anchoring an initiator on a metal material surface according to claim 1, characterized in that: The initiator used in method 1 can be directly anchored on the surface of the metal material, and the initiator has the structure of formula (1) or formula (2): R 1 ： Among them, R 2 is an alkane chain with 0 to 10 carbon units; R 3 is an ester group or an amide group; R 4 , R 5 is a hydrogen atom, a fluorine atom or a methyl group; X is a bromine or iodine atom; R 6 is an ester group or an amide group; R 7 , R 8 is a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or an aryl group; R 9 is an aliphatic group having 1 to 15 carbon atoms, an alkylthiol group having 1 to 15 carbon atoms, an alkoxy group having 1 to 15 carbon atoms, an aromatic group, an arylthiol group, an aryloxy group, a dialkylamino group or a diarylamino group having 1 to 15 carbon atoms; R 10 is an ester group or an amide group; R 11 is methyl or isopentane; R 12 is cyano or dimethyl butyrate; R 13 It is isobutyronitrile, isoheptanenitrile, and dimethyl isobutyrate.

3. The method for anchoring an initiator on a metal material surface according to claim 1, characterized in that: The initiator used in method 2 can be anchored on the surface of the hydroxylated metal material, and the initiator has the structure of formula (3) or (4): Among them, R 2 is an alkane chain with 0 to 10 carbon units; R 3 is an ester group or an amide group; R 4 , R 5 is a hydrogen atom, a fluorine atom or a methyl group; X is a bromine or iodine atom; R 6 is an ester group or an amide group; R 7 , R 8 is a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or an aryl group; R 9 is an aliphatic group having 1 to 15 carbon atoms, an alkylthiol group having 1 to 15 carbon atoms, an alkoxy group having 1 to 15 carbon atoms, an aromatic group, an arylthiol group, an aryloxy group, a dialkylamino group or a diarylamino group having 1 to 15 carbon atoms; R 10 is an ester group or an amide group; R 11 is methyl or isopentane; R 12 is cyano or dimethyl butyrate; R 13 isobutyronitrile, isoheptanenitrile, dimethyl isobutyrate. 14 , R 15 , R 16 It is a chlorine atom, a hydroxyl group, a methyl group, a methoxy group, or an ethoxy group.

4. The method for anchoring an initiator on a metal material surface according to any one of claims 1 to 3, characterized in that: The metal materials include iron, chromium, manganese, nickel, gold, silver, copper, lithium, sodium, potassium, indium, titanium, palladium, aluminum and alloys thereof.

5. A method for grafting anionic copolymers on the surface of a metal material by surface initiated polymerization, characterized in that: The method includes preparing a reaction solution, surface initiation polymerization and post-treatment, which are specifically as follows: (1) Preparation of reaction solution: A reaction solution of a non-gaseous monomer is prepared: the reactants include an anionic monomer, a comonomer, and a reaction additive, and the molar ratio of the anionic monomer to the comonomer is 1.0:(0.1-10.0), and the molar ratio of the anionic monomer to the reaction additive is 1.0:(0.001-0.5); the reactants are dissolved in a solvent, oxygen in the reaction system is removed, and the reaction system is stored away from light to serve as a reaction solution for surface initiated polymerization; A reaction solution of a gas monomer is prepared: a solvent and a reaction additive are injected into a reactor under a nitrogen atmosphere, and the reactor is slowly filled with the gas monomer at -40°C; the reactants include anionic monomers, comonomers, and reaction additives, and the molar ratio of the anionic monomer to the comonomer is 1.0:(0.1-10.0), and the molar ratio of the anionic monomer to the reaction additive is 1.0:(0.001-0.5); the reactants are dissolved in a solvent, oxygen in the reaction system is removed, and the reaction system is stored away from light to prepare a reaction solution for surface-initiated free radical polymerization; (2) Surface polymerization and post-treatment: The reaction solution prepared in step (1) is uniformly applied to the surface (1 to 100 cm) of the metal material anchored with the initiator as claimed in claim 1. 2 ), reacting under heating or light conditions; after the reaction is completed, taking out the metal material and fully rinsing it with an ultra-dry solvent to remove the reaction solution attached to the surface of the metal material; drying the cleaned metal material in a vacuum drying oven at 60 to 100° C. for 12 to 48 hours to obtain the anionic copolymer-modified metal material.

6. The method for grafting anionic copolymers on the surface of a metal material by surface initiated polymerization according to claim 5, characterized in that: The anionic monomer has the structure of formula (5): R 6 ： Among them, R 1 , R 2 , R 3 is a fluorine atom, a trifluoromethyl group or a perfluoroalkane chain having 2 to 5 carbon units; R 4 is a methylene group, an oxygen atom, an ester group or a carbon group; R 3 is an ester group or an amide group; R 5 is a perfluoroether chain having 1 to 10 carbon units or an alkane chain having 0 to 3 carbon units; R 7 is a carbonyl group, a sulfonyl group, or an alkane chain having 0 to 2 carbon units; R 8 is trifluoromethyl, methyl, ethyl, n-propyl, isopropyl, phenyl, p-trifluoromethylphenyl, p-methoxyphenyl or biphenyl; R 9 It is trifluoromethyl, methyl, ethyl or a perfluoroether chain having 1 to 10 carbon units.

7. The method for grafting anionic copolymers on the surface of a metal material by surface initiated polymerization according to claim 5, characterized in that: When preparing the reaction solution of the non-gaseous monomer, the comonomers used include trifluoroethyl methacrylate, trifluoroethyl acrylate, hexafluoroisopropyl methacrylate, hexafluorobutyl acrylate, pentafluoropropyl methacrylate, hexafluorobutyl methacrylate, heptafluorobutyl methacrylate, heptafluorobutyl acrylate, octafluoropentyl methacrylate, dodecafluoroheptyl methacrylate, perfluorooctyl methacrylate, perfluoroundecyl methacrylate, (perfluorocyclohexyl) methacrylate, pentafluorostyrene, perfluorobutyl methacrylate, hexafluorobutyl methacrylate, hepta ... heptafluorobutyl methacrylate, heptafluoropentyl methacrylate, heptafluorobutyl methacrylate, heptafluorobutyl methacrylate, heptafluoropentyl methacrylate, heptafluorobutyl methacrylate, heptafluorobutyl methacrylate, heptafluoropentyl methacrylate, heptafluorobutyl methacrylate, heptafluorobutyl methacrylate, heptafluoropentyl methacrylate, heptafluorobutyl methacrylate, heptafluoropentyl methacrylate, heptafluorobutyl methacrylate, heptafluorobutyl methacrylate, heptafluoropentyl methacrylate, hep One or more of fluoroethyl vinyl ether, perfluoropropyl vinyl ether, 2-(heptafluoropropoxy)hexafluoropropyltrifluorovinyl ether, perfluoro(3-oxapent-4-ene)sulfonyl fluoride, perfluoro(4-methyl-3,6-dioxa-7-octene)sulfonyl fluoride, methacrylic acid (ester) derivatives, acrylic acid (ester) derivatives, alkenyl ether derivatives, vinyl acetate derivatives, acrylamide derivatives, N-vinyl pyrrolidone derivatives, N-vinyl caprolactam derivatives, and styrene derivatives.

8. The method for grafting anionic copolymers on the surface of a metal material by surface initiated polymerization according to claim 5, characterized in that: When preparing the reaction solution of the gas monomer, the comonomers used include one or more of tetrafluoroethylene, vinylidene fluoride, chlorotrifluoroethylene, hexafluoropropylene, ethylene, propylene, alkenyl ether derivatives, vinyl acetate derivatives, N-vinyl pyrrolidone derivatives, and N-vinyl caprolactam derivatives.

9. The method for grafting anionic copolymers on the surface of a metal material by surface initiated polymerization according to claim 5, characterized in that: The reaction additive is one of azo compounds, peroxides, dithiocarbonates, trithiocarbonates, xanthates, dithiocarbamates, perfluoroalkyl halides, and alkyl halides; one or more combinations of porphyrin compounds, dihydrophenazine, phenothiazine, and phenoxazine; and the solvent is one or more combinations of dimethyl sulfoxide, N,N-dimethylformamide, carbonates, N-methylpyrrolidone, acetonitrile, ethyl acetate, and acetone.

10. The method for grafting anionic copolymers on the surface of a metal material by surface initiated polymerization according to claim 5, characterized in that: The reaction conditions are as follows: when heating, the heating temperature is 40-120°C and the reaction time is 1-72 hours; when irradiating with light, a light source with an emission wavelength of 250-700nm is used and the reaction time is 1-36 hours.

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