KR20080001655A - Dispersing agent of metal nanoparticles with polyethyleneimine derivative and use thereof - Google Patents

Abstract

The present invention is based on a polyethyleneimine having a number average molecular weight of 400 or more, wherein at least one H-NH in the skeleton is a metal of a polyethyleneimine derivative substituted with at least one functional group selected from the group consisting of a metal bonding group and a solvent-affinity group. A dispersant for nanoparticles. The present invention also relates to a method for producing metal nanoparticles using the dispersant and to metal nanoparticles produced by the method.

By using the dispersing agent of the metal nanoparticles of the polyethyleneimine derivative of the present invention, it is possible to easily and conveniently prepare the metal nanoparticles without aggregation in various solvents.

Description

Dispersant of metal nanoparticles with polyethyleneimine derivatives and use thereof {DISPERSING AGENT OF METAL NANOPARTICLE COMPOSED OF POLYETHYLENIMINE DERIVATIVE AND USE HEREOF}

1 is a scanning electron microscope (SEM) photograph of the silver nanoparticles prepared in Preparation Example 1. FIG.

2 is a result of analyzing the components of the silver nanoparticles prepared in Preparation Example 1 by an energy dispersive X-ray spectrometer (EDX).

3 is a scanning electron microscope (SEM) photograph of the silver nanoparticles prepared in Preparation Example 6. FIG.

4 is a scanning electron microscope (SEM) photograph of the silver nanoparticles prepared in Preparation Example 7. FIG.

5 is a scanning electron microscope (SEM) photograph of the silver nanoparticles prepared in Preparation Example 8. FIG.

6 is a scanning electron microscope (SEM) photograph of the silver nanoparticles prepared in Preparation Example 9. FIG.

The present invention relates to a dispersant for metal nanoparticles made of polyethyleneimine derivatives, a method for preparing metal nanoparticles using the same, and metal nanoparticles prepared by the method.

Nanoparticle materials range in size from a few nanometers (nm) to a few hundred nanometers. As they decrease in size, the surface-to-mass ratio of the particles increases, increasing the surface area per unit mass. In addition, as the energy state of the electron gets closer to the molecule, physical properties appear completely different from those of the bulk material. Increasing the surface area and activation of nanomaterials affects the change of physical properties as the melting point of particles decreases, and also affects the change of optical and electrical properties due to quantum effects, which can be applied to new optoelectronic materials.

Synthesis methods of metal nanoparticles known to date include a gas phase method synthesized using a high voltage in a vacuum state, and a liquid phase method prepared using an organic solvent and a polymer. Among these, the gas phase synthesis method has a disadvantage of high manufacturing cost and low productivity and workability. On the other hand, the wet synthesis method is relatively easy, productivity, workability, and has a relatively low cost of manufacturing has been widely used.

However, since the metal nanoparticles produced by the wet synthesis method is unstable in itself and agglomerates over time and loses their properties as nanoparticles, dispersants can be prepared to prevent the metal nanoparticles from being agglomerated in solution. Will be used. When a reducing agent is added to a solution in which a dispersant and a metal ion are dissolved together, metal ions are reduced to form metal nanoparticles. Polyvinylpyrrolidone (PVP), polyethyleneglycol, and Cetyltrimethylammonium bromide (CTAB) are widely used as dispersants. Reducing agents are mainly NaBH ₄ , H ₂ , Hydrazine, ascorbic acid, etc. In the case of ethylene glycol (EG), dimethylsulfoxide (DMSO), dimethylformamide (DMF), etc., it is a solvent and functions as a reducing agent. However, in the conventional method, the dispersing agent and the reducing agent have to be put separately, and there is a problem that the reaction solvent is also possible only in polar solvents such as water, EEG, DMF, and DMSO. In addition, since the solubility of the prepared metal nanoparticles in the solvent is determined by the dispersant present on the surface, it is necessary to develop a dispersant having solubility in various solvents.

The present invention is to provide a dispersing agent of metal nanoparticles made of polyethyleneimine derivative which can act as a dispersant so that there is no aggregation phenomenon in the solvent and at the same time reduce metal ions to metal nanoparticles.

In addition, to provide a method for producing metal nanoparticles using the dispersant of the metal nanoparticles and the metal nanoparticles prepared by the method.

The present invention has a polyimide of formula (I) or formula (II) having a number average molecular weight of 400 or more as a skeleton, and at least one H-NH in the skeleton is substituted with at least one functional group selected from the group consisting of a metal bonding group and a solvent-affinity group. A dispersant for metal nanoparticles of polyethylenimine derivatives is provided.

[Formula 1]

H (-NHCH ₂ CH _2- ) _n NH ₂

[Formula 2]

In addition, the present invention is a first step of dissolving the dispersant of the metal nanoparticles of the polyethyleneimine derivative in a solvent; And

It provides a method for producing metal nanoparticles comprising a second step of reducing the metal ions in the metal salt by adding a metal salt or a solution in which the metal salt is dissolved in the solution of the first step.

The present invention also provides a metal nanoparticle produced by the above method.

Hereinafter, the present invention will be described in detail.

The dispersing agent of the metal nanoparticles according to the present invention is a dispersing agent of metal nanoparticles made of polyethyleneimine derivatives, wherein the polyethyleneimine derivative is a linear polyethyleneimine of Formula 1 having a number average molecular weight of 400 or more, or a number average molecular weight of 400 or more of A branched polyethyleneimine is used as a skeleton, and at least one H-NH present in the polyethyleneimine skeleton has a structure substituted with at least one functional group selected from the group consisting of a metal bonding group and a solvent-affinity group.

[Formula 1]

H (-NHCH ₂ CH _2- ) _n NH ₂

[Formula 2]

The metal-bonding functional group is a functional group capable of chemically bonding with metal ions and / or metal nanoparticles, including, but not limited to,-[A] _a -PO ₃ R ¹ R ² ,-[A] _a -NR ³ R ⁴ ,-[A] _a -CONR ⁵ R ⁶ ,-[A] _a -O (CH ₂ CH ₂ O) _b R ⁷ ,-[A] _a -SO ₃ R ⁸ ,-[A] _a -NO ₂ ,-[A] _a -OH,-[A] _a -SH,-[A] _a -COOH, and the like; A is C ₁ to C ₃₀ linear or branched alkylene, or C ₆ to C ₃₀ arylene; A is 0 or 1; R ¹ to R ⁸ are each independently H, a C ₁ to C ₃₀ linear or branched alkyl group, or C ₆ to C ₃₀ aryl group; B may be an integer between 1 and 6.

In addition, the solvent affinity functional group is a functional group having affinity with a solvent, and non-limiting examples thereof include C ₁ to C ₃₀ linear or branched alkyl group, C ₆ to C ₃₀ aryl group,-[A] _a -PO ₃ R ¹ R ² ,-[A] _a -NR ³ R ⁴ ,-[A] _a -CONR ⁵ R ⁶ ,-[A] _a -O (CH ₂ CH ₂ O) _b R ⁷ ,- [A] _a -SO ₃ R ⁸ ,-[A] _a -NO ₂ ,-[A] _a -OR ⁹ ,-[A] _a -SR ¹⁰ ,-[A] _a -COOR ¹¹ ,-[A] _a -COR ¹² and the like; A is C ₁ to C ₃₀ linear or branched alkylene, or C ₆ to C ₃₀ arylene; A is 0 or 1; R ¹ to R ¹² are each independently H, a C ₁ to C ₃₀ linear or branched alkyl group, or C ₆ to C ₃₀ aryl group; B may be an integer between 1 and 6.

Polyethylenimine has metal-bonding functional groups such as amines, but the introduction of other metal-bonding functionalities that bind well to metal ions and metal nanoparticles can further increase affinity for metal ions and metal nanoparticles. By introducing the polyethyleneimine by controlling the type of the metal-bonded functional groups and the number of functional groups, it is possible to provide a dispersant made of polyethyleneimine derivatives having suitable affinity for various metals.

In addition, amines have affinity for polar solvents as hydrophilic functional groups, and polyethyleneimine is well soluble in polar solvents. However, introduction of long alkyl chains or aromatic functional groups into polyethyleneimine can produce hydrophobic polyethyleneimine derivatives, and the degree of hydrophobicity can be controlled by adjusting the amount of functional groups introduced. In addition, by controlling the type and number of hydrophilic functional groups in polyethyleneimine, the degree of hydrophilicity can also be controlled. Accordingly, polyethyleneimine derivatives whose degree of polarity is adjusted from hydrophilicity to hydrophobicity can be used as homogeneous dispersants in solvents of various polarities.

Formula 3 shows an example of a linear polyethyleneimine derivative in which a metal bonding functional group and a solvent affinity functional group are respectively bonded to one or more amine atoms in a molecule of the polyethyleneimine derivative which is a dispersant for metal nanoparticles according to the present invention. In addition, Formula 4 shows an example of a branched polyethyleneimine derivative of the polyethyleneimine derivative which is a dispersant of the metal nanoparticles according to the present invention.

[Formula 3]

In Formula 3, R is H, R _metalbinding , or R _solubilizing ; R _metalbinding is a metal bonding functional group; R _solubilizing is a solvent affinity functional group.

[Formula 4]

In Formula 4, R is H, R _metalbinding , or R _solubilizing ; R _metalbinding is a metal bonding functional group; R _solubilizing is a solvent affinity functional group.

The polyethyleneimine derivative used as the dispersing agent of the metal nanoparticles according to the present invention may be prepared from the polyethyleneimine of Formula 1 or Formula 2 having a number average molecular weight of 400 or more. Specifically, since the amine group exists in polyethyleneimine, the amine group is used. By carrying out a reaction such as nucleophilic substitution reaction or amidation, the metal bonding functional group and / or the solvent affinity functional group can be easily introduced.

On the other hand, the method for producing a metal nanoparticle according to the present invention, the polyimide of the formula (1) or formula (2) having a number average molecular weight of 400 or more as a skeleton, H of at least one -NH in the skeleton is a metal bonding functional group and solvent affinity. Dissolving a dispersing agent of metal nanoparticles of polyethyleneimine derivatives substituted with one or more functional groups selected from the group consisting of functional groups in a solvent; And

It may comprise a second step of reducing the metal ions in the metal salt by adding a metal salt or a solution in which the metal salt is dissolved in the solution of the first step.

In the method for producing metal nanoparticles according to the present invention, the dispersant of the metal nanoparticles of the polyethylenimine derivative not only acts as a dispersant to prevent the metal ions and the metal nanoparticles to be produced from agglomerating in a solvent, and the metal ion It acts as a kind of reducing agent to reduce to metal nanoparticles.

The amount of the reactant used in the preparation of the nanoparticles is not particularly limited, but polyethyleneimine derivative: metal salt: solvent = 0.0001 to 30 parts by weight: 0.01 to 30 parts by weight: 40 to 99.9 parts by weight. If the polyethyleneimine derivative is less than 0.0001 parts by weight, the metal salt is not stabilized sufficiently, so that particles having a particle size of 1 μm or more are formed. If the polyethyleneimine derivative is more than 30 parts by weight, it is not easy to remove it in the washing step. There is.

Moreover, although reaction temperature changes with solvent conditions, -25 degreeC-200 degreeC is preferable. The reaction does not occur at a temperature below -25 ° C, and a problem of excessively large particles occurs above 200 ° C.

In the method for preparing metal nanoparticles according to the present invention, the metal bonding functional group is-[A] _a -PO ₃ R ¹ R ² ,-[A] _a -NR ³ R ⁴ ,-[A] _a -CONR ⁵ R ⁶ ,-[A] _a -O (CH ₂ CH ₂ O) _b R ⁷ ,-[A] _a -SO ₃ R ⁸ ,-[A] _a -NO ₂ ,-[A] _a -OH,-[ A] _a -SH and-[A] _a -COOH; A is C ₁ to C ₃₀ linear or branched alkylene, or C ₆ to C ₃₀ arylene; A is 0 or 1; R ¹ to R ⁸ are each independently H, a C ₁ to C ₃₀ linear or branched alkyl group, or C ₆ to C ₃₀ aryl group; B may be an integer between 1 and 6.

In addition, the solvent-affinity functional group is a C ₁ ~ C ₃₀ linear or branched alkyl group, C ₆ ~ C ₃₀ aryl group,-[A] _a -PO ₃ R ¹ R ² ,-[A] _a -NR ³ R ⁴ ,-[A] _a -CONR ⁵ R ⁶ ,-[A] _a -O (CH ₂ CH ₂ O) _b R ⁷ ,-[A] _a -SO ₃ R ⁸ ,-[A ] _a -NO ₂ ,-[A] _a -OR ⁹ ,-[A] _a -SR ¹⁰ ,-[A] _a -COOR ¹¹ and-[A] _a -COR ¹² ; A is C ₁ to C ₃₀ linear or branched alkylene, or C ₆ to C ₃₀ arylene; A is 0 or 1; R ¹ to R ¹² are each independently H, a C ₁ to C ₃₀ linear or branched alkyl group, or C ₆ to C ₃₀ aryl group; B may be an integer between 1 and 6.

In the method of manufacturing metal nanoparticles according to the present invention, the metal may be one or more transition metals or alloys thereof selected from the group consisting of Ag, Au, Pd, Pt, Ni, and Cu, but is not limited thereto. Salts may be salts of such transition metals or alloys.

In the method for producing metal nanoparticles according to the present invention, the solvent is not particularly limited as long as it is a solvent normally used for reduction of metal salts. Non-limiting examples of solvents include water, methanol, ethanol, propanol, isopropanol, butanol, pentanol, hexanol, DMSO, DMF, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, ethelene glycol diethyl ether, propylene glycol, propylene glycol propyl ether, propylene glycol methyl ether acetate, N-methyl pyrrolidone, methyl isobutyl ketone, methyl ethyl ketone, acetonitrile, THF, hexadecane, pentadecane, tetradecane, tridecane, dodecane, undecane, decane, nonane, octane, heptane , hexane, xylene, toluene, benzene, etc., but is not limited thereto. These solvent can be used individually or in mixture of 2 or more types.

The present invention also provides a metal nanoparticle produced by the method for producing a metal nanoparticle.

(Example)

Hereinafter, the present invention will be described in detail with reference to the following Examples. However, the following examples are merely to illustrate the present invention and the present invention is not limited by the following examples.

[A. Synthesis of Polyethylenimine Derivatives]

Polyethylenimine used Aldrich reagent of number average molecular weight 423 (straight chain; L), 600 (branched; B), 10,000 (branched; B), 60,000 (branched; B). Polyethyleneimine derivatives were synthesized by a certain ratio substitution reaction of each polyethyleneimine.

(Example 1: Synthesis of Lau _0.18 LPEI ₄₂₃ )

A solution containing 43.0 g of linear polyethyleneimine having a number average molecular weight of 423 (1 mol based on monomer), 49.85 g (0.20 mol) of bromododecane, 30.4 g (0.20 mol) of anhydrous K ₂ CO ₃ , and 300 g of 2-propanol were mixed for 48 hours. It was stirred at reflux. The reaction solution was cooled, diethyl ether 500 ml was added, and then washed three times with 200 ml of 0.1 N NaOH solution and once with 200 ml of deionized water. Drying with MgSO ₄ and distillation of the solvent under reduced pressure gave 58 g of Lau _0.18 LPEI ₄₂₃ substituted with 18% of Laurl group, the ¹ H-NMR data thereof is described below.

¹ H-NMR (DMSO-d ₆ , 500 MHz, ppm): 2.3 to 2.8 (broad, -NCH ₂ CH ₂ ), 1.2 to 1.9 (b, Lau CH ₂ ), 0.9 to 1.0 (t, Lau CH ₃ ) .

(Examples 2-5: Synthesis of Lau _0.46 LPEI ₄₂₃ , Lau _0.85 LPEI ₄₂₃ , Lau _0.19 BPEI ₁₀₀₀₀ and Lau _0.20 BPEI ₆₀₀₀₀ )

Lau _0.46 LPEI ₄₂₃ (Example 2), Lau _0.85 LPEI ₄₂₃ (Example 3), Lau _0.19 BPEI ₁₀₀₀₀ (Example 4) _0.20 BPEI ₆₀₀₀₀ (Example 5) was synthesized. ¹ H-NMR data of Lau _0.19 BPEI ₁₀₀₀₀ (Example 4) and Lau _0.20 BPEI ₆₀₀₀₀ (Example 5) are described below.

¹ H-NMR (CDCl ₃ , 500 MHz, ppm): 7.2 to 7.3 (br, C ₆ H ₅ ), 3.4 to 3.6 (br, -NCH ₂ CH ₂ ), 2.2 to 2.6 (br, NCH ₂ CH ₃ ) .

(Example 6. Synthesis of Lau _0.46 Sul _0.38 LPEI ₄₂₃ )

120.7 g of Lau _0.46 LPEI ₄₂₃ synthesized in Example 2, 48.8 g of 1,3-propane sultone, and 300 g of 2-propanol were stirred under reflux for 24 hours. The solution was cooled and the solvent was distilled under reduced pressure to obtain 168.2 g of Lau _0.46 Sul _0.38 PEI ₄₂₃ .

(Example 7. Synthesis of Lau _0.46 EtOH _0.54 LPEI ₄₂₃ )

120.7 g of Lau _0.46 LPEI ₄₂₃ synthesized in Example 2, 74.9 g of 2-bromoethanol, 92 g (0.60 mol) of anhydrous K ₂ CO ₃ , and 500 g of 2-propanol were stirred under reflux for 48 hours. After cooling, the solution was added with 1000 ml of diethyl ether, and then washed three times with 300 ml of 0.1 N NaOH solution and once with 200 ml of deionized water. Dry with MgSO ₄ and distill off the solvent under reduced pressure to give Lau _0.46 EtOH _0.54 PEI ₄₂₃ 147.6 g was obtained.

(Example 8. Synthesis of Ac _1.0 LPEI ₄₂₃ )

43.0 g of linear polyethyleneimine having a number average molecular weight of 423 (1 mol on a monomer basis) were dissolved in 200 ml of 2-propanol. 122 g (1.2 mol) of acetic anhydride was slowly added in an ice-bath, and the reaction mixture was heated to 60 ° C. for 6 hours. After completion of the reaction, the solvent was distilled under reduced pressure to obtain Ac _1.0 LPEI ₄₂₃ , the ¹ H-NMR data thereof is described below.

¹ H-NMR (D ₂ O, 500 MHz, ppm): 3.3-3.8 (broad, -NCH ₂ CH ₂ ), 2.0-2.2 (m, -NCOCH ₃ ).

(Example 9. Synthesis of Ben _0.30 LPEI ₄₂₃ )

Ben _0.30 LPEI ₄₂₃ was obtained by using benzyl bromide instead of Bromododecane and in the same manner as in Example 1. The ¹ H-NMR data thereof is described below.

¹ H-NMR (CDCl ₃ , 500 MHz, ppm): 7.2 to 7.3 (br, C ₆ H ₅ ), 3.4 to 3.6 (br, -NCH ₂ CH ₂ ), 2.2 to 2.6 (br, NCH ₂ CH ₃ ) .

(Experiment 1. Solubility Measurement)

Using the polyethyleneimine derivatives prepared in Examples 1 to 9, the solubility of the polyethyleneimine derivative in various solvents was measured, and the results are shown in Table 1 below.

H ₂ O DMSO IPA Acetone THF PGPE CH ₂ Cl ₂ Toluene Hexane Example 1 O O O ◎ ◎ O △ △ X Example 2 △ O O ◎ ◎ O △ △ X Example 3 X △ △ △ O O O O O Example 4 O O O ◎ ◎ O △ △ X Example 5 O O O ◎ ◎ O △ △ X Example 6 △ O O O O O O O O Example 7 O O O O O O O O O Example 8 △ O O ◎ ◎ O △ △ X Example 9 △ O O ◎ ◎ O △ △ X Comparative Example 1 ◎ ◎ O △ △ X X X X Comparative Example 2 ◎ ◎ O △ △ X X X X

Comparative Example 1: Branched Polyethyleneimine with Number Average Molecular Weight _60,000 (BPEI ₆₀₀₀₀ ; Aldrich)

Comparative Example 2: linear polyethyleneimine having a number average molecular weight of 423 (LPEI ₄₂₃ ; Aldrich)

In Table 1, ◎: very well recording, O: well recording, △: a little recording, X: not recording well.

According to Table 1, the polyethyleneimine derivatives synthesized in Examples 1 to 9 showed various solubility in various solvents. In particular, Lau _0.46 Sul _0.38 PEI ₄₂₃ It showed good solubility in all solvents.

[B. Preparation of Metal Nanoparticles Containing Polyethylenimine Derivatives]

The metal nanoparticles were dissolved in the reaction mixture by dissolving the polyethyleneimine derivative synthesized in Example, AgNO ₃ was added to the solution, followed by stirring at a constant temperature. The metal nanoparticles produced after the reaction were separated by centrifugation and purified by washing several times with deionized water.

(Production Example 1 of Metal Nanoparticles)

3.7 g of Lau _0.18 LPEI ₄₂₃ synthesized in Example 1 was dissolved in 30 ml of distilled water. After the solution was heated to 100 ° C., an aqueous solution of 4.3 g of AgNO ₃ dissolved in 10 ml of distilled water was added and reacted for 1 hour. The reactants were cooled and purified to obtain silver nanoparticles having an average size of 20 to 30 nm (FIG. 1, FIG. 2).

(Production Examples 2 to 5 of Metal Nanoparticles)

Silver nanoparticles were synthesized in the same manner as in Preparation Example 1 of the metal nanoparticles, except that the polyethyleneimine derivatives prepared in Examples 2 to 5 were used instead of the polyethyleneimine derivatives prepared in Example 1. Silver nanoparticles of 10-20 nm were prepared according to the dispersant and the reaction conditions.

(Production Example 6 of Metal Nanoparticles)

Except for using the polyethyleneimine derivative prepared in Example 6 instead of the polyethyleneimine derivative prepared in Example 1 and using THF as a solvent, the average size of 20 ~ 30 nm in the same manner as in Preparation Example 1 of the metal nanoparticles Silver nanoparticles (see FIG. 3) were prepared.

(Production Example 7 of Metal Nanoparticles)

Except for using the polyethyleneimine derivative prepared in Example 7 instead of the polyethyleneimine derivative prepared in Example 1 and using methanol as a solvent, the average size of 20 ~ 30 nm in the same manner as in Preparation Example 1 of the metal nanoparticles Silver nanoparticles (see FIG. 4) were prepared.

(Production Examples 8 to 9 of Metal Nanoparticles)

Except for using the polyethyleneimine derivatives prepared in Examples 8 to 9 instead of the polyethyleneimine derivatives prepared in Example 1 and using THF as a solvent, the average size of the metal nanoparticles was 40-40. 50 nm silver nanoparticles (see FIGS. 5 and 6) were prepared.

(Production Example 10 of Metal Nanoparticles)

Copper nanoparticles having an average size of 10 to 20 nm were prepared in the same manner as in Preparation Example 1, except that Cu (OAc) ₂ was used instead of AgNO ₃ .

By using the dispersing agent of the metal nanoparticles of the polyethyleneimine derivative of the present invention, it is possible to easily and conveniently prepare the metal nanoparticles without aggregation in various solvents.

Claims (10)

Polyethyleneimine having the number average molecular weight of 400 or more as the polyimide of formula (1) or formula (2) as a skeleton, wherein at least one H-NH in the skeleton is substituted with at least one functional group selected from the group consisting of a metal bonding group and a solvent-affinity group Dispersant of metal nanoparticles with derivatives. [Formula 1] H (-NHCH ₂ CH _2- ) _n NH ₂ [Formula 2]

The method of claim 1, wherein the metal-bonding functional group is-[A] _a -PO ₃ R ¹ R ² ,-[A] _a -NR ³ R ⁴ ,-[A] _a -CONR ⁵ R ⁶ ,-[A] _a -O (CH ₂ CH ₂ O) _b R ⁷ ,-[A] _a -SO ₃ R ⁸ ,-[A] _a -NO ₂ ,-[A] _a -OH,-[A] _a -SH and -[A] _a -COOH; A is C ₁ to C ₃₀ linear or branched alkylene, or C ₆ to C ₃₀ arylene; A is 0 or 1; R ¹ to R ⁸ are each independently H, a C ₁ to C ₃₀ linear or branched alkyl group, or C ₆ to C ₃₀ aryl group; B is a dispersant of metal nanoparticles, characterized in that an integer between 1 and 6. The method according to claim 1, wherein the solvent affinity group is a C ₁ ~ C ₃₀ linear or branched alkyl group, C ₆ ~ C ₃₀ aryl (aryl) group,-[A] _a -PO ₃ R ¹ R ² , -[A] _a -NR ³ R ⁴ ,-[A] _a -CONR ⁵ R ⁶ ,-[A] _a -O (CH ₂ CH ₂ O) _b R ⁷ ,-[A] _a -SO ₃ R ⁸ ,-[A] _a -NO ₂ ,-[A] _a -OR ⁹ ,-[A] _a -SR ¹⁰ ,-[A] _a -COOR ¹¹ and-[A] _a -COR ¹² ; A is C ₁ to C ₃₀ linear or branched alkylene, or C ₆ to C ₃₀ arylene; A is 0 or 1; R ¹ to R ¹² are each independently H, a C ₁ to C ₃₀ linear or branched alkyl group, or C ₆ to C ₃₀ aryl group; B is a dispersant of metal nanoparticles, characterized in that an integer between 1 and 6. Polyethyleneimine having the number average molecular weight of 400 or more as the polyimide of formula (1) or formula (2) as a skeleton, wherein at least one H-NH in the skeleton is substituted with at least one functional group selected from the group consisting of a metal bonding group and a solvent-affinity group A first step of dissolving a dispersant of metal nanoparticles as a derivative in a solvent; And A method for producing metal nanoparticles comprising the second step of reducing metal ions in the metal salt by adding a metal salt or a solution in which the metal salt is dissolved in the solution of the first step. [Formula 1] H (-NHCH ₂ CH _2- ) _n NH ₂ [Formula 2]

The method of claim 4, wherein the metal-bonding functional group is-[A] _a -PO ₃ R ¹ R ² ,-[A] _a -NR ³ R ⁴ ,-[A] _a -CONR ⁵ R ⁶ ,-[A] _a -O (CH ₂ CH ₂ O) _b R ⁷ ,-[A] _a -SO ₃ R ⁸ ,-[A] _a -NO ₂ ,-[A] _a -OH,-[A] _a -SH and -[A] _a -COOH; A is C ₁ to C ₃₀ linear or branched alkylene, or C ₆ to C ₃₀ arylene; A is 0 or 1; R ¹ to R ⁸ are each independently H, a C ₁ to C ₃₀ linear or branched alkyl group, or C ₆ to C ₃₀ aryl group; B is a method for producing metal nanoparticles, characterized in that an integer between 1 and 6. The method according to claim 4, wherein the solvent affinity group is a C ₁ ~ C ₃₀ linear or branched alkyl group, C ₆ ~ C ₃₀ aryl group,-[A] _a -PO ₃ R ¹ R ² , -[A] _a -NR ³ R ⁴ ,-[A] _a -CONR ⁵ R ⁶ ,-[A] _a -O (CH ₂ CH ₂ O) _b R ⁷ ,-[A] _a -SO ₃ R ⁸ ,-[A] _a -NO ₂ ,-[A] _a -OR ⁹ ,-[A] _a -SR ¹⁰ ,-[A] _a -COOR ¹¹ and-[A] _a -COR ¹² ; A is C ₁ to C ₃₀ linear or branched alkylene, or C ₆ to C ₃₀ arylene; A is 0 or 1; R ¹ to R ¹² are each independently H, a C ₁ to C ₃₀ linear or branched alkyl group, or C ₆ to C ₃₀ aryl group; B is a method for producing metal nanoparticles, characterized in that an integer between 1 and 6. The method of claim 4, wherein the polyethyleneimine derivative: metal salt: solvent = 0.0001 to 30 parts by weight: 0.01 to 30 parts by weight: 40 to 99.9 parts by weight. The method of claim 4, wherein the metal is one or more transition metals or alloys thereof selected from the group consisting of Ag, Au, Pd, Pt, Ni, and Cu. The method of claim 4, wherein the solvent is water, methanol, ethanol, propanol, isopropanol, butanol, pentanol, hexanol, DMSO, DMF, glycerol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol, propylene glycol propyl ether, propylene glycol methyl ether acetate, N-methyl pyrrolidone, methyl isobutyl ketone, methyl ethyl ketone, acetonitrile, THF, hexadecane, pentadecane, tetradecane, tridecane, dodecane, undecane, decane, nonane , octane, heptane, hexane, xylene, toluene, benzene The method for producing metal nanoparticles, characterized in that at least one selected from the group consisting of. Metal nanoparticles produced by the method of any one of claims 4 to 9.

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