Copper powder coated with organic matter and preparation method of copper powder
The preparation of ultrafine copper powder by evaporation and condensation followed by organic coating treatment solves the problem of easy oxidation of ultrafine copper powder, and improves its antioxidant and conductivity properties. It is suitable for fields such as electronics, conductive coatings and catalysts.
Patent Information
- Application Number
- CN202511590089.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-03
- Publication Date
- 2026-01-02
AI Technical Summary
Ultrafine copper powder is easily oxidized in air, affecting its conductivity and stability. Existing surface treatment methods are difficult to effectively improve its oxidation resistance.
Ultrafine copper powder was prepared by evaporation and condensation, and then coated by immersion in a solution containing organic substances such as oleic acid, lauric acid, and stearic acid. This coating process combined with organic substances such as 3,4-dihydroxyphenylpropionic acid and thiopropionamide formed a protective layer to improve its antioxidant properties and electrical conductivity.
It significantly improves the oxidation resistance and conductivity of ultrafine copper powder, enabling it to exhibit better stability and conductivity in composite materials.
Smart Images
Figure CN121244934A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of ultrafine copper powder technology, specifically relating to a copper powder coated with organic matter and its preparation method. Background Technology
[0002] Due to its surface effects, high electrical and thermal conductivity, copper powder, especially ultrafine copper powder, has been widely used in various fields such as electronics, conductive coatings, catalysts, and lubricant additives. However, ultrafine copper powder has high surface activity and is easily oxidized in air, forming copper oxide or cuprous oxide, which severely affects its conductivity. This has prompted the search for effective methods to improve the oxidation resistance of copper powder. The core advantage of copper-based thermally conductive adhesives lies in the high thermal conductivity of copper, but copper powder has problems such as easy oxidation, high density, and potential corrosion of substrates. Therefore, appropriate surface treatment is needed to optimize its performance. Common copper powder surface treatments include silver plating, tin plating, silane coupling agents, and organic acids. These methods typically involve constructing a protective layer or introducing functional groups on the surface of the copper powder through physical or chemical means to improve its oxidation resistance, dispersibility, and interfacial compatibility. Summary of the Invention
[0003] The purpose of this invention is to provide a copper powder coated with organic materials that has good coating effect, good antioxidant properties, and can be made into a composite material with good electrical conductivity, as well as a method for preparing the same.
[0004] The technical solution adopted by the present invention to achieve the above objectives is as follows: A method for preparing organically coated copper powder includes: adding ultrafine copper powder to an organic solution to obtain organically coated copper powder; the organic solution contains organic matter, including at least one of oleic acid, lauric acid, and stearic acid, and the content of organic matter in the organic solution is 0.1-10 mM. This invention, by immersing ultrafine copper powder in an organic solution containing at least one of oleic acid, lauric acid, and stearic acid, allows the oleic acid, lauric acid, or stearic acid to bind to the surface of the ultrafine copper powder, which can, to a certain extent, prevent the ultrafine copper powder from being oxidized, thereby improving the antioxidant properties of the ultrafine copper powder.
[0005] Preferably, the organic matter further includes 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide. This invention further improves the antioxidant properties of ultrafine copper powder by mixing 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide with oleic acid, and by adjusting the ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide at the same amount of organic matter used. This results in a composite material with better electrical conductivity.
[0006] More preferably, the mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid is 1:1-10; or the mass ratio of oleic acid to thiopropionamide is 1:0.5-3.
[0007] More preferably, in the preparation of organic-coated copper powder, the organic matter is oleic acid, 3,4-dihydroxyphenylpropionic acid and thiopropionamide, the mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid is 1:1-10, and the mass ratio of oleic acid to thiopropionamide is 1:0.5-3.
[0008] Preferably, the organic solution further comprises a solvent, which includes at least one of ethanol, propanol, and propylene glycol.
[0009] Preferably, the sphericity of the ultrafine copper powder is >95%; or, the purity of the ultrafine copper powder is >99%; or, the oxygen content of the ultrafine copper powder is 0.05-2%; or, the carbon content of the ultrafine copper powder is 0.02-0.5%.
[0010] Preferably, the particle size of the ultrafine copper powder is 0.1-12 μm.
[0011] Preferably, the ultrafine copper powder is prepared by evaporation and condensation.
[0012] Preferably, the amount of ultrafine copper powder used is 10-25 wt% of the organic solution.
[0013] Preferably, the organic solution is a mixture of organic matter and ethanol.
[0014] This invention discloses the organic-coated copper powder prepared by the above method.
[0015] Preferably, in the preparation of ultrafine copper powder, the ultrafine copper powder is prepared by evaporation and condensation method, in which plasma or laser is used for heating to obtain ultrafine copper powder.
[0016] More preferably, in the preparation of ultrafine copper powder, the particle size of the ultrafine copper powder is 0.1-12μm.
[0017] More preferably, in the preparation of ultrafine copper powder, the sphericity of the ultrafine copper powder is >95%.
[0018] More preferably, in the preparation of ultrafine copper powder, the copper powder purity of the ultrafine copper powder is >99%.
[0019] More preferably, in the preparation of ultrafine copper powder, the oxygen content of the ultrafine copper powder is 0.05-2%.
[0020] More preferably, in the preparation of ultrafine copper powder, the carbon content of the ultrafine copper powder is 0.02-0.5%.
[0021] Preferably, in the preparation of organic-coated copper powder, ultrafine copper powder is immersed in an organic solution, mixed and stirred at 20-40°C for 2-24 hours under an inert gas atmosphere, filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder.
[0022] More preferably, in the preparation of organic-coated copper powder, the organic solution is a mixture of organic matter and ethanol, and the organic matter includes at least one of oleic acid, lauric acid and stearic acid.
[0023] More preferably, in the preparation of organic-coated copper powder, the organic matter is oleic acid, 3,4-dihydroxyphenylpropionic acid and thiopropionamide.
[0024] More preferably, in the preparation of organic-coated copper powder, the content of organic matter in the organic solution is 0.1-10 mM.
[0025] More preferably, in the preparation of organic-coated copper powder, the amount of ultrafine copper powder used is 10-25 wt% of the organic solution.
[0026] More preferably, in the preparation of organic-coated copper powder, sulfosuccinic acid may also be added to the organic material, with the mass ratio of oleic acid to sulfosuccinic acid being 1:0.01-0.1. In this invention, when using oleic acid and 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide, sulfosuccinic acid may also be added. Under reasonable usage, sulfosuccinic acid interacts with oleic acid and 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide, improving the antioxidant properties of the ultrafine copper powder under the same organic material usage. After further processing into a composite material, it exhibits better electrical conductivity.
[0027] This invention employs an evaporation-condensation method to prepare copper powder, using plasma heating to obtain ultrafine copper powder. The ultrafine copper powder is then immersed in an organic solution for coating, resulting in organically coated copper powder. The organic solution contains at least one of oleic acid, lauric acid, and stearic acid, and also includes 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide. Therefore, it offers the following advantages: good antioxidant properties and good electrical conductivity when combined with epoxy resin and a curing agent to form a composite material. Thus, this invention provides a method for preparing organically coated copper powder with good coating effect, good antioxidant properties, and the ability to produce composite materials with good electrical conductivity. Attached Figure Description
[0028] Figure 1 This is an electron microscope image of copper powder.
[0029] Figure 2 Electron micrograph of copper powder coated on organic matter.
[0030] Figure 3 This is a graph showing the rate of weight gain due to oxidation.
[0031] Figure 4 This is a volume resistivity diagram. Detailed Implementation
[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0033] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.
[0034] Example 1: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder was prepared by evaporation-condensation method, in which plasma was used for heating to obtain ultrafine copper powder. The particle size of the ultrafine copper powder was 0.2-5μm, the sphericity was >95%, the copper powder purity was >99%, the oxygen content was 0.19%, and the carbon content was 0.04%.
[0035] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic matter and ethanol; the organic matter was oleic acid. The organic matter content in the organic solution was 1 mM, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0036] Example 2: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0037] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic matter and ethanol; the organic matter was lauric acid. The organic matter content in the organic solution was 1 mM, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0038] Example 3: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0039] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of an organic compound and ethanol; the organic compound was stearic acid. The organic compound content in the organic solution was 1 mM, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0040] Example 4: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0041] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic compounds and ethanol. The organic compounds were oleic acid, 3,4-dihydroxyphenylpropionic acid, and thiopropionamide. The organic compound content in the organic solution was 1 mM, the mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid was 1:8, the mass ratio of oleic acid to thiopropionamide was 1:2.5, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0042] Example 5: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0043] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic compounds and ethanol. The organic compounds were oleic acid, 3,4-dihydroxyphenylpropionic acid, and thiopropionamide. The organic compound content in the organic solution was 1 mM, the mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid was 1:2, the mass ratio of oleic acid to thiopropionamide was 1:0.8, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0044] Example 6: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0045] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic compounds and ethanol. The organic compounds were oleic acid, 3,4-dihydroxyphenylpropionic acid, thiopropionamide, and sulfosuccinic acid. The organic compound content in the organic solution was 1 mM. The mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid was 1:8, the mass ratio of oleic acid to thiopropionamide was 1:2.5, the mass ratio of oleic acid to sulfosuccinic acid was 1:0.08, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0046] Example 7: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0047] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic compounds and ethanol. The organic compounds were oleic acid, 3,4-dihydroxyphenylpropionic acid, thiopropionamide, and sulfosuccinic acid. The organic compound content in the organic solution was 1 mM. The mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid was 1:8, the mass ratio of oleic acid to thiopropionamide was 1:2.5, the mass ratio of oleic acid to sulfosuccinic acid was 1:0.02, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0048] Comparative Example 1: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0049] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was composed of a mixture of organic matter and ethanol. The organic matter consisted of oleic acid and 3,4-dihydroxyphenylpropionic acid. The organic matter content in the organic solution was 1 mM, the mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid was 1:8, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0050] Comparative Example 2: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0051] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic matter and ethanol. The organic matter consisted of oleic acid and thiopropionamide. The organic matter content in the organic solution was 1 mM, the mass ratio of oleic acid to thiopropionamide was 1:2.5, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0052] Comparative Example 3: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0053] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic compounds and ethanol. The organic compounds were oleic acid, 3,4-dihydroxyphenylpropionic acid, and thiopropionamide. The organic compound content in the organic solution was 1 mM, the mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid was 1:8, the mass ratio of oleic acid to thiopropionamide was 1:0.1, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0054] Comparative Example 4: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0055] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was composed of a mixture of organic compounds and ethanol. The organic compounds were oleic acid, 3,4-dihydroxyphenylpropionic acid, and thiopropionamide. The organic compound content in the organic solution was 1 mM, the mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid was 1:0.5, the mass ratio of oleic acid to thiopropionamide was 1:2.5, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0056] Comparative Example 5: A method for preparing copper powder coated with organic matter Preparation of ultrafine copper powder: Copper powder is prepared by evaporation-condensation method. In the evaporation-condensation method, plasma or laser is used for heating to obtain ultrafine copper powder. The particle size of ultrafine copper powder is 0.2-5μm, sphericity >95%, copper powder purity >99%, oxygen content is 0.19%, and carbon content is 0.04%.
[0057] Preparation of organic-coated copper powder: Ultrafine copper powder was immersed in an organic solution and mixed and stirred at 30°C for 12 hours under an inert gas atmosphere. The mixture was then filtered, washed successively with deionized water and ethanol, and dried to obtain organic-coated copper powder. The organic solution was a mixture of organic compounds and ethanol. The organic compounds were oleic acid, 3,4-dihydroxyphenylpropionic acid, and thiopropionamide. The organic compound content in the organic solution was 1 mM, the mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid was 1:0.5, the mass ratio of oleic acid to thiopropionamide was 1:0.1, and the amount of ultrafine copper powder used was 20 wt% of the organic solution.
[0058] Experimental example: The SEM image of the ultrafine copper powder prepared in Example 1 of this invention is shown below. Figure 1 As shown, the ultrafine copper powder obtained by this invention is in the form of spheres of varying sizes, with a particle size between 0.2 and 5 μm.
[0059] The SEM image of the organic-coated copper powder prepared in Example 1 of this invention is shown below. Figure 2 As shown, organic matter is adsorbed onto the surface of ultrafine copper powder through the adsorption of functional groups. The organic matter forms a molecular film on the surface of ultrafine copper powder, which can isolate air and prevent oxidation.
[0060] The antioxidant properties of the organic-coated copper powders prepared in the examples and comparative examples were tested. The organic-coated copper powders were placed in air and oxidized at 200°C for 1 hour. The oxidation weight gain was then compared, with uncoated copper powder added as a blank group. The oxidation weight gain results are shown below. Figure 3As shown, S1 is Example 1, S2 is Example 2, S3 is Example 3, S4 is Example 4, S5 is Example 5, S6 is Example 6, S7 is Example 7, D1 is Comparative Example 1, D2 is Comparative Example 2, D3 is Comparative Example 3, D4 is Comparative Example 4, D5 is Comparative Example 5, and B is the blank group. This invention uses an evaporation-condensation method to prepare copper powder. In this method, plasma heating is used to prepare ultrafine copper powder with a particle size of 0.2-5 μm, sphericity >95%, copper powder purity >99%, oxygen content of 0.19%, and carbon content of 0.04%. Then, the ultrafine copper powder is immersed in an organic solution for coating treatment to prepare organic-coated copper powder. The organic matter in the organic solution includes at least one of oleic acid, lauric acid, and stearic acid, and also includes 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide. This invention uses at least one of oleic acid, lauric acid, and stearic acid. Coated ultrafine copper powder exhibits better antioxidant effects compared to uncoated ultrafine copper powder. In this invention, when using oleic acid for coating, 3,4-dihydroxyphenylpropionic acid and thiopropionamide can be added together to prepare organically coated copper powder, resulting in better antioxidant effects within a specific dosage range. However, if the dosage of 3,4-dihydroxyphenylpropionic acid or thiopropionamide is low, the improvement effect compared to using only one type of 3,4-dihydroxyphenylpropionic acid or thiopropionamide is weaker. Furthermore, if the dosages of both 3,4-dihydroxyphenylpropionic acid and thiopropionamide are low, there is no significant improvement in the antioxidant performance of the organically coated copper powder. In this invention, when using oleic acid as the main coating agent for organic matter, in addition to 3,4-dihydroxyphenylpropionic acid and thiopropionamide, sulfosuccinic acid can also be added. The dosage of sulfosuccinic acid does not need to be very high to further improve the antioxidant performance of the obtained organically coated copper powder.
[0061] This invention uses copper powder coated with organic material prepared in the examples and comparative examples to form a composite material. The volume resistivity of the composite material is tested. The organic-coated copper powder is mixed uniformly with E51 epoxy resin and triethanolamine curing agent at a mass ratio of 8:1:1, and then coated onto the surface of a substrate to form a 1mm thick composite material. This material is cut into 15mm × 15mm pieces, and the volume resistivity is measured using a four-probe tester. Copper powder without organic coating is added as a blank group. The results are as follows: Figure 4As shown, S1 is Example 1, S2 is Example 2, S3 is Example 3, S4 is Example 4, S5 is Example 5, S6 is Example 6, S7 is Example 7, D1 is Comparative Example 1, D2 is Comparative Example 2, D3 is Comparative Example 3, D4 is Comparative Example 4, D5 is Comparative Example 5, and B is the blank group. This invention uses an evaporation-condensation method to prepare copper powder. In this method, plasma heating is used to prepare ultrafine copper powder with a particle size of 0.2-5 μm, sphericity >95%, copper powder purity >99%, oxygen content of 0.19%, and carbon content of 0.04%. Then, the ultrafine copper powder is immersed in an organic solution for coating treatment to prepare organic-coated copper powder. The organic matter in the organic solution includes at least one of oleic acid, lauric acid, and stearic acid, and also includes 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide. This invention uses at least one of oleic acid, lauric acid, and stearic acid... A coated ultrafine copper powder exhibits better conductivity than uncoated ultrafine copper powder. In this invention, when using oleic acid for coating, 3,4-dihydroxyphenylpropionic acid and thiopropionamide can be added to prepare organically coated copper powder, resulting in better conductivity within a specific dosage range. However, if the dosage of 3,4-dihydroxyphenylpropionic acid or thiopropionamide is low, the improvement effect compared to using only one of them is weaker. Furthermore, if the dosages of both 3,4-dihydroxyphenylpropionic acid and thiopropionamide are low, there is no significant improvement in the conductivity of the organically coated copper powder. In this invention, when using oleic acid as the main coating agent, in addition to 3,4-dihydroxyphenylpropionic acid and thiopropionamide, sulfosuccinic acid can also be added. The dosage of sulfosuccinic acid does not need to be very high to further improve the conductivity of the obtained organically coated copper powder.
[0062] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention.
[0063] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.
Claims
1. A method for preparing organically coated copper powder, comprising: Organically coated copper powder is prepared by adding ultrafine copper powder to an organic solution. The organic solution contains organic matter, including at least one of oleic acid, lauric acid and stearic acid, and the content of organic matter in the organic solution is 0.1-10 mM.
2. The method for preparing organic-coated copper powder according to claim 1, characterized in that: The organic compound also includes 3,4-dihydroxyphenylpropionic acid and / or thiopropionamide.
3. The method for preparing organic-coated copper powder according to claim 2, characterized in that: The mass ratio of oleic acid to 3,4-dihydroxyphenylpropionic acid is 1:1-10; or the mass ratio of oleic acid to thiopropionamide is 1:0.5-3.
4. The method for preparing organic-coated copper powder according to claim 1, characterized in that: The organic solution also contains a solvent, which includes at least one of ethanol, propanol and propylene glycol.
5. The method for preparing organic-coated copper powder according to claim 1, characterized in that: The sphericity of the ultrafine copper powder is >95%; or, the purity of the ultrafine copper powder is >99%; or, the oxygen content of the ultrafine copper powder is 0.05-2%; or, the carbon content of the ultrafine copper powder is 0.02-0.5%.
6. The method for preparing organic-coated copper powder according to claim 1, characterized in that: The particle size of the ultrafine copper powder is 0.1-12 μm.
7. The method for preparing organic-coated copper powder according to claim 1, characterized in that: The ultrafine copper powder was prepared by evaporation and condensation.
8. The method for preparing organic-coated copper powder according to claim 1, characterized in that: The amount of ultrafine copper powder used is 10-25 wt% of the organic solution.
9. The method for preparing organic-coated copper powder according to claim 1, characterized in that: The organic solution is a mixture of organic matter and ethanol.
10. Organic copper-coated powder prepared by any of the methods described in claims 1-9.