Preparation method of monodisperse high-crystallization copper powder

Abstract

The invention discloses a preparation method of monodisperse high-crystallization copper powder, and belongs to the technical field of metal powder preparation. The method is used for solving the technical problem of how to regulate and control the process of synthesizing cuprous oxide powder and copper powder so as to improve the dispersity and crystallinity of the synthesized copper powder when the copper powder is synthesized in the prior art. A preparation method of monodisperse high-crystallization copper powder comprises the following steps that cuprous oxide powder is added into deionized water to be evenly mixed, and a cuprous oxide mixture is obtained; ascorbic acid and chelating resin are added into deionized water, and complexing liquid is prepared; and blending the cuprous oxide mixture and the complexing solution, then carrying out heating reaction, and filtering to obtain copper powder particles. Wherein the cuprous oxide powder is prepared by reaction of copper nitrate, gelatin and hexadecyl trimethyl ammonium bromide. Through adsorption of the template agent and the chelate resin, the copper powder which is regular in morphology, high in crystallinity and uniform in dispersion is prepared.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal powder preparation, in particular to a preparation method of monodisperse high-crystallinity copper powder. BACKGROUND

[0002] The preparation method of copper powder can be divided into physical method and chemical method according to whether chemical reaction occurs in the preparation process. The physical method mainly includes atomization method, ball milling method, physical vapor deposition method and the like, which does not involve the change of chemical composition. The chemical method is to control the crystallization process of copper from the atomic or molecular level, which is simple and effective; by controlling the chemical reaction conditions, the particle size, morphology and purity of copper powder can be accurately controlled; therefore, the chemical method has great potential and advantage in the preparation process of ultrafine copper powder, and excellent ultrafine copper powder can be easily obtained by optimizing the reaction conditions.

[0003] In the chemical method, the copper powder obtained by direct reduction with strong reducing agent is relatively loose, and the particle size distribution of the copper powder is uneven; after the copper ions are quickly reduced, the growth process of copper crystals is very rapid, a large number of crystal nuclei are easily formed in a short time, and the aggregation and growth are very significant under this condition, which is easy to form loose and porous particles. Patent application CN102941351A discloses a preparation method of ultrafine copper powder. In cuprous oxide, a ferrous carboxylate complex solution is added, and ultrafine copper powder is prepared without adding a dispersant; wherein, a glucose aqueous solution is added to the copper salt aqueous solution, and cuprous oxide powder is synthesized by reduction. However, the particle size and morphology of cuprous oxide powder have a key influence on the morphology, dispersity and crystallinity of the synthesized copper powder; how to control the particle size and morphology of the twice-reduced product is of great significance for preparing copper powder with high crystallinity and high dispersity.

[0004] In view of the technical defects, a solution is proposed. SUMMARY

[0005] The present application aims to provide a preparation method of monodisperse high-crystallinity copper powder, which solves the technical problem of how to control the process of synthesizing cuprous oxide powder and copper powder in the prior art, thereby improving the dispersity and crystallinity of the synthesized copper powder.

[0006] The purpose of the present application can be achieved by the following technical solutions: A preparation method of monodisperse high-crystallinity copper powder, comprising the following steps: S1, cuprous oxide powder is added to deionized water and mixed to obtain a cuprous oxide mixture; S2, ascorbic acid and chelating resin are added to deionized water to prepare a complex solution; the cuprous oxide mixture and the complex solution are mixed, then heated to 55-65 DEG C and kept for 2-3 h, and then filtered to obtain monodisperse high-crystallinity copper powder.

[0007] The copper powder particles are prepared by using ascorbic acid as a weak reducing agent, and chelating resin adsorption and uniform dispersion of cuprous oxide powder.

[0008] Further, the preparation method of the chelating resin comprises the following steps: A1, the solvent, chloroacetyl polystyrene resin and ethyl chloroacetate are uniformly mixed to obtain a reaction system; NaOH solution is added dropwise in the reaction system, and the reaction is carried out at 25-30℃ for 5-6h; then, filtration, washing and drying to constant weight are carried out to synthesize the β-diketone chelating resin; NaOH solution is added dropwise in the methanol solvent to form sodium methoxide; the sodium methoxide can deprotonate the hydrogen atom at the α-position of the aromatic ketone as a base reagent to generate a stable enol anion, and then the acyl carbon in the ethyl chloroacetate is subjected to nucleophilic addition to form an intermediate; then, the intermediate is removed from the ethanol molecule to undergo intramolecular rearrangement to synthesize the product, i.e. the chelating resin containing the β-diketone structure.

[0009] The reaction formula of the synthesis of the chelating resin containing the β-diketone structure by the reaction of chloroacetyl polystyrene resin and ethyl chloroacetate is as follows:

[0010] A2, the β-diketone chelating resin and nitric acid are blended, and then 85-90wt% concentrated sulfuric acid is added dropwise and reacted at 70-80℃; then, filtration is carried out to synthesize the nitro-substituted β-diketone chelating resin; the nitro-substituted β-diketone chelating resin, ethanol and stannous chloride are uniformly mixed and reacted at room temperature for 2-3h to generate an intermediate; the intermediate is added to a sodium hydroxide solution, mixed and filtered to obtain a product; the product is washed and dried to prepare the chelating resin.

[0011] The above reaction cannot be carried out completely, and thus a considerable amount of unreacted benzene rings and benzene ring-like chain segments remain in the resin. The β-diketone chelating resin is subjected to nitration and nitro reduction reaction to finally prepare the chelating resin grafted with amino groups. The concentrated sulfuric acid is used as a sulfonating agent, the β-diketone chelating resin is grafted with nitro groups, stannous chloride is used as a reducing agent, and then the sodium hydroxide solution is added to promote phase transfer, and thus the solid chelating resin is prepared.

[0012] Further, in step A1, the amount ratio of the solvent, chloroacetyl polystyrene resin and ethyl chloroacetate is 200mL:30-50g:15-25g, and the drying temperature is 65-70℃.

[0013] Further, in step A2, the amount ratio of the beta-diketone-like chelating resin, nitric acid and concentrated sulfuric acid is 10-20g:50mL:3-10mL; the amount ratio of the nitro-substituted beta-diketone-like chelating resin, ethanol and stannous chloride is 5-15g:50mL:0.3-0.5g; and the mass ratio of the intermediate and the sodium hydroxide solution is 1:1.

[0014] Further, the preparation method of the cuprous oxide powder comprises the following steps: B1, ethanol and water are blended to obtain a solvent; the solvent, copper nitrate, gelatin and cetyltrimethylammonium bromide are added into a reaction kettle, the temperature of the reaction kettle is set to 50-60 DEG C, and the reaction time is 1-2h to obtain a product; B2, 0.15-0.2g / mL of NaOH solution is added dropwise into the product, and the mixture is reacted at 55-65 DEG C for 10-20min, then hydrazine hydrate is added, and the reaction is continued; after the reaction is completed, a product is obtained; the product is centrifuged to obtain a reduced product; the reduced product is washed and vacuum dried to obtain the cuprous oxide powder.

[0015] The cuprous oxide powder is synthesized after the reaction by using the surfactant cetyltrimethylammonium bromide as a template agent and gelatin as a reducing agent.

[0016] Further, in step B1, the mass ratio of ethanol and water is 1:2-3, and the amount ratio of the solvent, copper nitrate, gelatin and cetyltrimethylammonium bromide is 100mL:2-5g:2.5-4.5g:1.5-2.5g; in step B2, the amount ratio of the product, NaOH solution and hydrazine hydrate is 105-110mL:3-6mL:100-120μL; the centrifugal speed is 2000-3000r / min, and the centrifugal time is 15-20min.

[0017] Further, in step S1, the amount ratio of the cuprous oxide powder and deionized water is 10-20g:150-200mL.

[0018] Further, in step S2, the amount ratio of ascorbic acid, chelating resin and deionized water is 5-10g:3-8g:150-200mL; and the amount ratio of the cuprous oxide mixture and the complexing solution is 150-200mL:160-210mL.

[0019] The present application has the following advantages: 1. The copper powder is synthesized by two-step reduction method in the present application. The copper nitrate is reduced to cuprous oxide powder by using gelatin as reducing agent and hexadecyl trimethyl ammonium bromide as template agent. The addition of surfactant can provide steric hindrance and electrostatic repulsion to prevent the agglomeration of cuprous oxide particles, and further regulate the particle size of the synthesized cuprous oxide powder. The hexadecyl trimethyl ammonium bromide will gather and arrange into ordered microstructure in the solution, prevent the agglomeration of cuprous oxide powder, and form fine cuprous oxide powder with specific structure. The size of cuprous oxide particles is significantly reduced, and the uniformity is good.

[0020] 2. The copper powder is prepared by further reducing the cuprous oxide powder with weak reducing agent ascorbic acid. The self-made chelating resin is used to disperse and adsorb the cuprous oxide powder in the present application. The cuprous oxide powder is directly reduced to copper powder in situ, and the copper powder has the advantages of high dispersity and high crystallinity. The chelating resin with beta-diketone structure is synthesized by using chloroacetyl polystyrene resin and ethyl chloroacetate as monomers. The amino functional groups are grafted on the benzene ring of the chelating resin by specific nitration and reduction reaction, so that the specific adsorption and reduction of cuprous oxide by multi-functional groups are realized.

[0021] 3. The two-step weak reduction is used to replace one-time strong reduction in the present application. The reaction process of synthesizing cuprous oxide powder and copper powder is regulated to avoid the too rapid crystal growth of copper caused by strong reduction, so that a large number of crystal nuclei are formed in a short time. The copper powder prepared by the present application has uniform particle size distribution and small particle size. The prepared copper powder has regular morphology, clear crystal boundary and high crystallinity by SEM observation. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0023] Figure 1 The electron micrograph of monodisperse high crystalline copper powder prepared in Example 9 of the present application; Figure 2 The electron micrograph of monodisperse high crystalline copper powder prepared in Comparative Example 1 of the present application; Figure 3 The electron micrograph of monodisperse high crystalline copper powder prepared in Comparative Example 2 of the present application; Figure 4 The electron micrograph of monodisperse high crystalline copper powder prepared in Comparative Example 3 of the present application. DETAILED DESCRIPTION

[0024] The technical solutions of the present application will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0025] The chloroacetyl polystyrene resin used in the embodiments 1-3 of the present application is purchased from Nanjing Maikofei High-efficiency Separation Carrier Co., Ltd., with a cross-linking degree of 10% and a particle size of 200 μm; the gelatin used in the embodiments 4-6 of the present application is purchased from Jiangsu Yankao Biological Engineering Co., Ltd., with a product number of 101 and a CAS number of 9000-70-8.

[0026] Embodiment 1 The present embodiment provides a preparation method of a chelating resin for monodisperse high-crystalline copper powder, comprising the following steps. A1, select a 500 mL three-necked flask, add 200 mL of solvent methanol, 30 g of chloroacetyl polystyrene resin and 15 g of ethyl chloroacetate into the three-necked flask, mix uniformly to obtain a reaction system. Add 5 mL of 0.1 mol / L NaOH solution into the reaction system, and then heat the three-necked flask to 25℃, react for 5 h, then filter, wash with deionized water for three times, and dry at 65℃ until constant weight to synthesize a β-diketone-like chelating resin.

[0027] A2, add 10 g of the β-diketone-like chelating resin and 50 mL of 0.1 mol / L nitric acid into a 250 mL three-necked flask, add 15 mL of 85 wt% concentrated sulfuric acid into the three-necked flask, and then react at 70℃ for 3 h, then filter to synthesize a nitro-substituted β-diketone-like chelating resin. Select 5 g of the nitro-substituted β-diketone-like chelating resin and 50 mL of ethanol solvent, and then add into a 250 mL three-necked flask, further add 0.3 g of a catalyst stannous chloride, and then react at room temperature for 2 h to generate an intermediate. Blend the intermediate and 0.1 mol / L sodium hydroxide solution according to a mass ratio of 1:1, then filter to obtain a product; wash the product with deionized water, and dry until constant weight to synthesize a chelating resin.

[0028] Embodiment 2 The present embodiment provides a preparation method of a chelating resin for monodisperse high-crystalline copper powder, comprising the following steps. A1, select a 500 mL three-necked flask, add 200 mL of solvent methanol, 30 g of chloroacetyl polystyrene resin and 15 g of ethyl chloroacetate into the three-necked flask, mix uniformly to obtain a reaction system. Add 5 mL of 0.1 mol / L NaOH solution into the reaction system, and then heat the three-necked flask to 25℃, react for 5 h, then filter, wash with deionized water for three times, and dry at 65℃ until constant weight to synthesize a β-diketone-like chelating resin.

[0029] A2, 20g of the β-diketone-like chelating resin and 50mL of 0.1mol / L nitric acid were added into a 250mL three-necked flask, 25mL of 90wt% concentrated sulfuric acid was added dropwise into the three-necked flask, and the reaction was carried out at 80℃ for 6h, and then filtered to synthesize the nitro chelating resin. 15g of the nitro chelating resin and 50mL of ethanol solvent were added into a 250mL three-necked flask, and 0.5g of the catalyst stannous chloride was added, and the reaction was carried out at room temperature for 3h to generate an intermediate. The intermediate and 0.1mol / L sodium hydroxide solution were blended at a mass ratio of 1:1, and then filtered to obtain a product; the product was washed with deionized water and dried at 70℃ until the weight was constant to synthesize the chelating resin.

[0030] Example 3 The embodiment provides a preparation method of a chelating resin for monodisperse high-crystalline copper powder, and the method comprises the following steps: A1, 200mL of a solvent methanol, 50g of chloroacetyl polystyrene resin and 25g of ethyl chloroacetate were added into a 500mL three-necked flask, and mixed to obtain a reaction system. 10mL of 0.1mol / L NaOH solution was added dropwise into the reaction system, the three-necked flask was heated to 30℃, and the reaction was carried out for 6h, and then filtered, and the product was washed with deionized water for three times and dried at 70℃ until the weight was constant to synthesize the β-diketone-like chelating resin.

[0031] A2, 20g of the β-diketone-like chelating resin and 50mL of 0.1mol / L nitric acid were added into a 250mL three-necked flask, 25mL of 90wt% concentrated sulfuric acid was added dropwise into the three-necked flask, and the reaction was carried out at 80℃ for 6h, and then filtered to synthesize the nitro chelating resin. 15g of the nitro chelating resin and 50mL of ethanol solvent were added into a 250mL three-necked flask, and 0.5g of the catalyst stannous chloride was added, and the reaction was carried out at room temperature for 3h to generate an intermediate. The intermediate and 0.1mol / L sodium hydroxide solution were blended at a mass ratio of 1:1, and then filtered to obtain a product; the product was washed with deionized water and dried at 70℃ until the weight was constant to synthesize the chelating resin.

[0032] Example 4 The embodiment provides a preparation method of cuprous oxide powder for monodisperse high-crystalline copper powder, and the method comprises the following steps: B1, ethanol and water were blended at a mass ratio of 1:2 to obtain a solvent; 100mL of the solvent, 2g of copper nitrate, 2.5g of gelatin and 1.5g of a template agent cetyltrimethylammonium bromide were added into a reaction kettle, and stirred uniformly, and then the temperature of the reaction kettle was set to 50℃, and the reaction was carried out for 1h to obtain a product.

[0033] B2, 5 mL, 0.18 g / mL of NaOH solution was added dropwise in 108 mL of the product, reacted at 60°C for 15 min, then 110 μL of hydrazine hydrate was added, and the reaction was continued for 6 min, after the reaction was completed, the product was obtained; the product was centrifuged at 2500 r / min for 18 min to obtain the reduced product. The reduced product was washed with water and ethanol alternately for three to four times, and vacuum dried at 77°C to constant weight to prepare cuprous oxide powder.

[0034] Example 5 The present example provides a preparation method of cuprous oxide powder for monodisperse high-crystalline copper powder, comprising the following steps: B1, ethanol and water were blended according to a mass ratio of 1:3 to obtain a solvent; 100 mL of the solvent, 3 g of copper nitrate, 3.5 g of gelatin and 2 g of template agent cetyltrimethylammonium bromide were added into a reaction kettle, stirred uniformly first, then the temperature of the reaction kettle was set to 55°C and the reaction time was set to 1.5 h to obtain a product.

[0035] B2, 5 mL, 0.18 g / mL of NaOH solution was added dropwise in 108 mL of the product, reacted at 60°C for 15 min, then 110 μL of hydrazine hydrate was added, and the reaction was continued for 6 min, after the reaction was completed, the product was obtained; the product was centrifuged at 2500 r / min for 18 min to obtain the reduced product. The reduced product was washed with water and ethanol alternately for three to four times, and vacuum dried at 77°C to constant weight to prepare cuprous oxide powder.

[0036] Example 6 The present example provides a preparation method of cuprous oxide powder for monodisperse high-crystalline copper powder, comprising the following steps: B1, ethanol and water were blended according to a mass ratio of 1:3 to obtain a solvent; 100 mL of the solvent, 3 g of copper nitrate, 3.5 g of gelatin and 2 g of template agent cetyltrimethylammonium bromide were added into a reaction kettle, stirred uniformly first, then the temperature of the reaction kettle was set to 55°C and the reaction time was set to 1.5 h to obtain a product.

[0037] B2, 5 mL, 0.18 g / mL of NaOH solution was added dropwise in 108 mL of the product, reacted at 60°C for 15 min, then 110 μL of hydrazine hydrate was added, and the reaction was continued for 6 min, after the reaction was completed, the product was obtained; the product was centrifuged at 2500 r / min for 18 min to obtain the reduced product. The reduced product was washed with water and ethanol alternately for three to four times, and vacuum dried at 77°C to constant weight to prepare cuprous oxide powder.

[0038] Example 7 The present example provides a preparation method of monodisperse high-crystalline copper powder, comprising the following steps: S1, 10 g of cuprous oxide powder prepared in Example 4 was added into 150 mL of deionized water, and the cuprous oxide powder was uniformly dispersed in the deionized water by stirring to obtain a cuprous oxide mixture; S2, 5 g of ascorbic acid and 3 g of the chelate resin prepared in Example 1 were added into 150 mL of deionized water to prepare a complexing solution; 150 mL of the cuprous oxide mixture and 160 mL of the complexing solution were mixed, and the temperature was raised to 55°C and maintained for 2 h, and then filtered to obtain copper powder particles.

[0039] S3, the copper powder particles were centrifuged at 2000 r / min for 5 min, washed with deionized water, and vacuum freeze-dried at 0°C to prepare monodisperse high-crystalline copper powder.

[0040] Example 8 The present example provides a method for preparing monodisperse high-crystalline copper powder, comprising the following steps: S1, 15 g of cuprous oxide powder prepared in Example 5 was added into 180 mL of deionized water, and the cuprous oxide powder was uniformly dispersed in the deionized water by stirring to obtain a cuprous oxide mixture; S2, 8 g of ascorbic acid and 6 g of the chelate resin prepared in Example 2 were added into 180 mL of deionized water to prepare a complexing solution; 180 mL of the cuprous oxide mixture and 200 mL of the complexing solution were mixed, and the temperature was raised to 60°C and maintained for 2.5 h, and then filtered to obtain copper powder particles.

[0041] S3, the copper powder particles were centrifuged at 2500 r / min for 8 min, washed with deionized water, and vacuum freeze-dried at -2°C to prepare monodisperse high-crystalline copper powder.

[0042] Example 9 The present example provides a method for preparing monodisperse high-crystalline copper powder, comprising the following steps: S1, 20 g of cuprous oxide powder prepared in Example 6 was added into 200 mL of deionized water, and the cuprous oxide powder was uniformly dispersed in the deionized water by stirring to obtain a cuprous oxide mixture; S2, 10 g of ascorbic acid and 8 g of the chelate resin prepared in Example 3 were added into 200 mL of deionized water to prepare a complexing solution; 200 mL of the cuprous oxide mixture and 210 mL of the complexing solution were mixed, and the temperature was raised to 65°C and maintained for 3 h, and then filtered to obtain copper powder particles.

[0043] S3, the copper powder particles were centrifuged at 3000 r / min for 10 min, washed with deionized water, and vacuum freeze-dried at -2°C to prepare monodisperse high-crystalline copper powder.

[0044] Comparative Example 1 The difference between the present comparative example and Example 9 is that step A2 is cancelled; and the β-diketone chelating resin of the same mass is used to replace the chelating resin.

[0045] Comparative Example 2 The difference between the present comparative example and Example 9 is that when preparing the cuprous oxide powder, no template agent cetyltrimethylammonium bromide is added in the synthesis product in step B1.

[0046] Comparative Example 3 The difference between the present comparative example and Example 9 is that when preparing the monodisperse high-crystalline copper powder, the sodium borohydride of the same mass is used to replace the ascorbic acid.

[0047] Performance test: The copper powder prepared in Examples 7-9 has good dispersibility, and the agglomeration phenomenon between the particles is rare. Figure 1 It can be seen that the copper powder prepared in Example 9 has regular grain morphology, clear grain boundary, high crystallinity, and good and uniform dispersibility between the copper powders.

[0048] In Comparative Example 1, the β-diketone chelating resin of the same mass is used to replace the β-diketone chelating resin grafted with amino, and the adsorption and chelation performance of the cuprous oxide powder is poor. Figure 2 It can be seen that the synthesized cuprous oxide powder has a small amount of agglomeration phenomenon.

[0049] In Comparative Example 2, no template agent is added to control the morphology of the synthesis product when preparing the cuprous oxide powder. Figure 3 It can be seen that the synthesized copper powder has agglomeration and irregular shape problems. Figure 4 In Comparative Example 3, the strong reducing agent sodium borohydride is used to replace the weak reducing agent ascorbic acid; the cuprous oxide is rapidly reduced, and the aggregation growth is significant, forming a loose and porous particle; according to the SEM image of the copper powder prepared in Comparative Example 3, it can be seen that the copper powder prepared in Comparative Example 3 has a large agglomeration particle size, and the shape is irregular, and there are many defects such as holes and cracks, and the crystallinity is low.

[0050] The above content is only an example and description of the structure of the present application, and those skilled in the art can make various modifications or supplements or use similar ways to replace the described specific examples, as long as they do not deviate from the structure of the present application or exceed the scope defined by the present claims, and should belong to the protection scope of the present application.

[0051] In the description of the specification, reference to "one embodiment", "an example", "a specific example" or the like means that a particular feature, structure, material or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. The appearances of the phrases "in one embodiment", "an example", "a specific example" or the like in various places in the specification are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0052] The preferred embodiments of the application disclosed above are only to help explain the application. The preferred embodiments do not describe all the details of the application and limit the application to the specific embodiments. Obviously, many modifications and variations can be made in light of the contents of the specification. The specification selects and specifically describes these embodiments in order to better explain the principles and practical application of the application, so that those skilled in the art can well understand and utilize the application. The application is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing monodisperse highly crystalline copper powder, characterized in that, Includes the following steps: S1. Add cuprous oxide powder to deionized water and mix well to obtain a cuprous oxide mixture; S2, ascorbic acid and chelating resin are added to deionized water to prepare a complexing solution; the cuprous oxide mixture is mixed with the complexing solution, then heated to 55-65℃ and kept at that temperature for 2-3 hours, and then filtered to obtain monodisperse highly crystalline copper powder.

2. The method for preparing monodisperse highly crystalline copper powder according to claim 1, characterized in that, The method for preparing the chelating resin includes the following steps: A1. Solvent, chloroacetyl polystyrene resin and ethyl chloroacetate were mixed to obtain a reaction system; NaOH solution was added dropwise to the reaction system, and the temperature was raised to 25-30℃. The reaction was carried out for 5-6 hours, then filtered, washed and dried to constant weight to synthesize a β-diketone chelating resin. A2. A β-diketone chelating resin is mixed with nitric acid, and then 85-90 wt% concentrated sulfuric acid is added dropwise. The mixture is reacted at 70-80℃ and then filtered to synthesize a nitrated β-diketone chelating resin. The nitrated β-diketone chelating resin is mixed with ethanol and stannous chloride and reacted at room temperature for 2-3 hours to generate an intermediate. The intermediate is added with sodium hydroxide solution, mixed, and filtered to obtain the product. The product is washed and dried to prepare the chelating resin.

3. The method for preparing monodisperse highly crystalline copper powder according to claim 2, characterized in that, In step A1, the ratio of solvent, chloroacetyl polystyrene resin and ethyl chloroacetate is 200mL:30-50g:15-25g, and the drying temperature is 65-70℃.

4. The method for preparing monodisperse highly crystalline copper powder according to claim 2, characterized in that, In step A2, the ratio of β-diketone chelating resin, nitric acid, and concentrated sulfuric acid is 10-20g:50mL:3-10mL; the ratio of nitrated β-diketone chelating resin, ethanol, and stannous chloride is 5-15g:50mL:0.3-0.5g; and the mass ratio of intermediate to sodium hydroxide solution is 1:

1.

5. The method for preparing monodisperse highly crystalline copper powder according to claim 1, characterized in that, The method for preparing the cuprous oxide powder includes the following steps: B1. Ethanol and water are mixed to obtain a solvent; the solvent, copper nitrate, gelatin and hexadecyltrimethylammonium bromide are added to a reaction vessel, the temperature of the reaction vessel is set to 50-60℃ and the reaction time is 1-2h to obtain the product; B2. Add 0.15-0.2 g / mL NaOH solution to the product and react at 55-65℃ for 10-20 min. Then add hydrazine hydrate and continue the reaction. After the reaction is complete, the product is obtained. Centrifuge the product to obtain the reduced product. Wash the reduced product and vacuum dry it to prepare cuprous oxide powder.

6. The method for preparing monodisperse highly crystalline copper powder according to claim 5, characterized in that, In step B1, the mass ratio of ethanol to water is 1:2-3, and the volume ratio of solvent, copper nitrate, gelatin, and hexadecyltrimethylammonium bromide is 100mL:2-5g:2.5-4.5g:1.5-2.5g. In step B2, the volume ratio of product, NaOH solution, and hydrazine hydrate is 105-110mL:3-6mL:100-120μL. The centrifugation speed is 2000-3000r / min, and the centrifugation time is 15-20min.

7. The method for preparing monodisperse highly crystalline copper powder according to claim 1, characterized in that, In step S1, the ratio of cuprous oxide powder to deionized water is 10-20g:150-200mL.

8. The method for preparing monodisperse highly crystalline copper powder according to claim 1, characterized in that, In step S2, the ratio of ascorbic acid, chelating resin and deionized water is 5-10g:3-8g:150-200mL, and the ratio of cuprous oxide mixture and complexing solution is 150-200mL:160-210mL.

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