Paper-wrapped flat copper wires and preparation method therefor

Abstract

The present invention belongs to the technical field of paper-wrapped flat copper wires. Provided are paper-wrapped flat copper wires and a preparation process therefor. The surface of aramid insulation paper is activated by using plasma method surface modification and combining sodium nitrite and an active oxygen gas, thereby significantly improving the surface energy of the aramid insulation paper, such that the interface bonding force between the aramid insulation paper and a metal conduit is significantly improved, and the prepared paper-wrapped flat copper wires have higher stability. By coating the surface of the aramid insulation paper with a layer of a mixed solution of silicon dioxide, silicon carbide and a rare earth oxide, the mechanical strength and oxidation resistance of the aramid insulation paper are further improved, and the service life of the prepared paper-wrapped flat copper wires is prolonged. By means of hot pressing, the acting force between aramid cellulose chains is enhanced, the combination is tighter, and the linear density is increased, such that the tearing index and tensile index of the aramid insulation paper are significantly improved.

Description

Paper-wrapped copper flat wire and preparation method thereof TECHNICAL FIELD

[0001] The present application belongs to the technical field of paper-wrapped copper flat wire and relates to a paper-wrapped copper flat wire and a preparation method thereof. BACKGROUND

[0002] The paper-wrapped copper flat wire process is a common wire and cable manufacturing process, mainly used in the fields of household appliances, communication equipment, electrical equipment, etc. This process has the characteristics of simple manufacturing process, good insulation performance, excellent electrical conductivity, etc., and has been widely used in many fields. In the field of communication equipment, paper-wrapped copper flat wire is usually used for the manufacture of telephone lines, network lines and other transmission lines to ensure stable signal transmission. In addition, it is also widely used in the fields of construction, transportation and aerospace.

[0003] The outer layer of the paper-wrapped copper flat wire is usually wrapped with insulating paper. This insulating paper has good insulation performance and high-temperature resistance, which can ensure the stable electrical performance of the copper flat wire during use and prevent current leakage or short circuit and other problems. At the same time, the insulating paper can also provide additional mechanical protection to enhance the durability and reliability of the copper flat wire. However, single-layer insulating paper is prone to wear and tear during use, resulting in a short service life of the paper-wrapped copper flat wire. In order to solve the above problems, the insulating paper is modified to improve its wear resistance and insulation. SUMMARY

[0004] The purpose of the present application is to provide a paper-wrapped copper flat wire and a preparation method thereof, which has good wear resistance and high insulation.

[0005] The purpose of the present application can be achieved by the following technical solutions:

[0006] A paper-wrapped copper flat wire comprises an inner layer of metal copper conductor and an outer layer of modified aramid insulation paper. The preparation process of the modified aramid insulation paper is as follows,

[0007] S1: Place the aramid insulation paper in a nitrogen atmosphere at room temperature and normal pressure, and treat the surface with plasma generated by a 400W power source for 120s;

[0008] S2: Uniformly coat the aramid insulation paper treated by plasma with sodium nitrite with a mass concentration of 10%, and after 20 minutes, wash it with deionized water and blow it with active oxygen gas at 60°C at a flow rate of 10m / s for 2h to dry the surface of the aramid insulation paper;

[0009] S3: Mix silicon dioxide, silicon carbide and rare earth oxides in a mass ratio of 1:1:1, uniformly mix them, and then grind them in a ball mill at a speed of 300r / min for 2h to obtain a mixture;

[0010] S4: dispersing the mixture in deionized water to obtain a mixed solution with a mass concentration of 30%, and performing ultrasonic treatment on the mixed solution for 1 h to obtain a uniformly dispersed mixed solution;

[0011] S5: uniformly spraying the mixed solution obtained in S4 on the aramid insulation paper obtained in S2, and performing drying treatment by laser irradiation;

[0012] S6: hot-pressing the aramid insulation paper obtained in S5 at 70°C under a pressure of 500-700 N for 200-300 s, and then standing for 12 h to obtain the modified aramid insulation paper layer.

[0013] Further, the spraying parameters of the solution in S5 are a spraying distance of 80 mm and a spraying rate of 60 mm / s.

[0014] Further, the rare earth oxide in S3 is one or more of cerium oxide, lanthanum oxide, and praseodymium oxide.

[0015] Further, the particle size of the powder obtained by grinding in S3 is 300-400 mesh.

[0016] Further, the laser irradiation parameters in S5 are a laser power of 250 W, a temperature of 80°C, and an irradiation time of 30 min.

[0017] Further, the thickness of the modified aramid insulation paper layer obtained in S6 is 0.8-1.2 mm.

[0018] A preparation method of a paper-covered copper flat wire, the preparation process of the paper-covered copper flat wire being as follows,

[0019] S71: drawing a metal copper wire through a flat die on a drawing equipment, and then calendering the drawn wire through a calendering die on the drawing equipment to obtain a copper flat wire;

[0020] S72: transferring the drawn and calendered copper flat wire into an annealing furnace, and annealing the copper flat wire at a speed of 150 m / min under a nitrogen atmosphere;

[0021] S73: using an ultrasonic cleaning machine to ultrasonically clean the annealed copper flat wire to obtain a clean copper flat wire;

[0022] S74: using nitrogen gas at 50°C to blow the copper flat wire at a flow rate of 8 m / s to obtain a surface-dry and clean copper flat wire;

[0023] S75: coating the modified aramid insulation paper layer on the outside of the copper flat wire to obtain a final product of a paper-covered copper flat wire.

[0024] Further, the thickness of the copper flat wire obtained in S71 is 2.7 mm.

[0025] The application first processes the surface of aramid insulation paper by plasma, and active ions in the plasma can bombard the surface of aramid, so that the surface structure is finely adjusted, thereby improving the interfacial bonding strength of the insulation paper, and the optimized surface performance helps to enhance the compatibility of the insulation paper with other materials, and improve the stability and reliability of the overall system.

[0026] Then, the surface of the aramid insulation paper is activated by sodium nitrite and active oxygen gas, the activation treatment can enhance the bonding force between fibers, improve the tensile strength and tear strength of the insulation paper, and at the same time maintain good thermal stability, the sodium nitrite treatment can significantly improve the surface energy of the aramid insulation paper, the improvement of the surface energy helps to enhance the adhesion of the insulation paper with other materials; sodium nitrite reacts with the surface of aramid fiber to introduce new functional groups, which can increase the reactivity of the surface of the insulation paper, and the surface energy of the aramid insulation paper is further activated by active oxygen gas, so that the interfacial bonding force between the aramid insulation paper and the metal conduit is significantly improved, and the prepared paper-wrapped copper flat wire has higher stability; the activation treatment can also improve the wettability and coatability of the aramid insulation paper, which makes the insulation paper more easily achieve uniform coverage and close fit when coated with other materials.

[0027] The application coats a mixed solution of silicon dioxide, silicon carbide and rare earth oxide on the surface of the aramid insulation paper after activation treatment, further improving the mechanical strength of the aramid insulation paper, silicon carbide as a high-hardness material can effectively enhance the structure of the aramid insulation paper, making its surface more hard and not easy to be worn; the addition of rare earth oxide can effectively improve the insulation performance of the aramid insulation paper and promote material compounding, so that the combination of silicon dioxide, silicon carbide and aramid insulation paper is more compact; the rare earth oxide also has certain antioxidant and anti-aging properties, which can delay the aging process of the aramid insulation paper during use, prolonging the service life of the prepared paper-wrapped copper flat wire.

[0028] The application strengthens the force between aramid cellulose chains by hot pressing, so that the combination is more compact and the linear density increases, thereby significantly improving the tear index and tensile index of the aramid insulation paper.

[0029] The beneficial effects of the application are as follows:

[0030] This invention utilizes plasma surface modification combined with the activation of aramid insulating paper surface using sodium nitrite and reactive oxygen species. This significantly enhances the surface energy of the aramid insulating paper, thereby significantly improving the interfacial bonding force between the aramid insulating paper and the metal conduit, resulting in higher stability of the prepared paper-wrapped copper flat wire. Furthermore, by coating the aramid insulating paper surface with a mixed solution of silicon dioxide, silicon carbide, and rare earth oxides, this invention further improves the mechanical strength and oxidation resistance of the aramid insulating paper, extending the service life of the prepared paper-wrapped copper flat wire. Finally, through hot pressing, this invention strengthens the interaction forces between aramid cellulose chains, resulting in tighter bonding and increased linear density, thus significantly improving the tear index and tensile index of the aramid insulating paper. Detailed Implementation

[0031] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with embodiments, is provided below.

[0032] Example 1

[0033] The preparation process of the modified aramid insulating paper layer is as follows.

[0034] S1: Place the aramid insulating paper at room temperature and pressure, and in a nitrogen atmosphere, perform plasma surface treatment for 120 seconds using a 400W power supply.

[0035] S2: Apply 10% sodium nitrite evenly to the aramid insulating paper that has undergone plasma surface treatment. After leaving it for 10 minutes, wash it with deionized water and then blow it with active oxygen gas at 60°C at a flow rate of 10 m / s for 2 hours to dry the surface of the aramid insulating paper.

[0036] S3: Mix silicon dioxide, silicon carbide and lanthanum oxide in a mass ratio of 1:1:1. After mixing evenly, grind the mixture in a ball mill at a speed of 300 r / min for 2 hours to obtain a mixture.

[0037] S4: Disperse the mixture in deionized water to obtain a mixed solution with a mass concentration of 30%. Sonicate the mixed solution for 1 hour to obtain a uniformly dispersed mixed solution.

[0038] S5: The mixed solution prepared in S4 is uniformly sprayed onto the surface of the aramid insulating paper prepared in S2 at a spraying distance of 80mm and a spraying speed of 60mm / s. The paper is then dried by laser irradiation with a laser power of 250W, a temperature of 80℃, and an irradiation time of 30min.

[0039] S6: The aramid insulation paper prepared in S5 is hot-pressed at 70 DEG C, the pressure is 500N, the hot-pressing time is 300s, and the hot-pressed paper is placed for 12h to obtain the modified aramid insulation paper layer.

[0040] The preparation process of the paper-covered copper flat wire is as follows,

[0041] S71: The metal copper wire is drawn through a flat die on a drawing equipment, and then is calendered through a calendering die on the drawing equipment to obtain a copper flat wire;

[0042] S72: The copper flat wire drawn and calendered is transferred into an annealing furnace, and is annealed at a speed of 150 m / min under a nitrogen atmosphere;

[0043] S73: The annealed copper flat wire is ultrasonically cleaned by using an ultrasonic cleaning machine to obtain a clean copper flat wire;

[0044] S74: The copper flat wire is blown with nitrogen gas at a flow rate of 8 m / s and a temperature of 50 DEG C to obtain a surface-dried and clean copper flat wire;

[0045] S75: The modified aramid insulation paper layer is wrapped around the copper flat wire to obtain a final product of paper-covered copper flat wire.

[0046] In S6 of Example 2, the pressure is 700N, the hot-pressing time is 200s, and the other conditions are the same as those in Example 1.

[0047] In Comparative Example 1, the aramid insulation paper is not subjected to the S1 plasma surface treatment, and the other conditions are the same as those in Example 1.

[0048] In Comparative Example 2, the aramid insulation paper is not subjected to the S2 surface activation treatment, and the other conditions are the same as those in Example 1.

[0049] In Comparative Example 3, the aramid insulation paper is not subjected to the S5 surface mixed solution coating treatment, and the other conditions are the same as those in Example 1.

[0050] In Comparative Example 4, the aramid insulation paper is not subjected to the S6 hot-pressing treatment, and the other conditions are the same as those in Example 1.

[0051] The paper-covered copper flat wire prepared is subjected to mechanical strength test according to GB / T 6109.2-2008, and the specific test method is as follows,

[0052] The test sample is installed on a tensile testing machine, and the installation direction of the sample is ensured to be consistent with the tensile direction;

[0053] The tensile speed is set to 2mm / s, the tensile force is set to 200N, and the tensile time is set to 20s;

[0054] The tensile condition is recorded and the tensile strength of the sample is analyzed.

[0055] The paper-wrapped copper flat wire prepared is tested for bending modulus according to GB / T 9341-2008, the paper-wrapped copper flat wire sample is fixed on the clamp of a bending tester, to ensure that the sample does not slide or shift during the test, a constant bending force is applied to the sample by the testing equipment, so that the sample is bent and deformed.

[0056] The conductivity of the test sample is tested according to GB / T 17650.2-2021 standard, and the lower the conductivity, the better the insulation.

[0057] The experimental results of the examples and comparative examples are as follows,

[0058]

[0059] From the experimental results, it can be seen that the modification of aramid insulation paper effectively improves the mechanical strength and insulation of the prepared product paper-wrapped copper flat wire, and example 1 is the best embodiment.

[0060] When the application is used:

[0061] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content without departing from the scope of the technical solution of the present application, and any equivalent embodiments with equivalent changes and modifications are still within the scope of the present application.

Claims

1. A paper-insulated copper flat wire, comprising an inner layer of metallic copper conductor and an outer layer of modified aramid insulating paper, characterized in that, The preparation process of the modified aramid insulating paper layer is as follows. S1: Place the aramid insulating paper at room temperature and pressure, and in a nitrogen atmosphere, perform plasma surface treatment for 120 seconds using a 400W power supply. S2: Apply 10% sodium nitrite evenly to the aramid insulating paper that has undergone plasma surface treatment. After leaving it for 10 minutes, wash it with deionized water and then blow it with active oxygen gas at 60°C at a flow rate of 10 m / s for 2 hours to dry the surface of the aramid insulating paper. S3: Mix silicon dioxide, silicon carbide and rare earth oxides in a mass ratio of 1:1:

1. After mixing evenly, grind them in a ball mill at a speed of 300 r / min for 2 hours to obtain a mixture. S4: Disperse the mixture in deionized water to obtain a mixed solution with a mass concentration of 30%. Sonicate the mixed solution for 1 hour to obtain a uniformly dispersed mixed solution. S5: The mixed solution obtained in S4 is uniformly sprayed onto the surface of the aramid insulating paper obtained in S2, and then dried by laser irradiation. S6: The aramid insulating paper obtained in S5 is hot-pressed at 70°C with a pressure of 500-700N for 200-300s. After hot pressing, it is left to stand for 12h to obtain the modified aramid insulating paper layer.

2. The paper-wrapped copper flat wire according to claim 1, characterized in that, The spraying parameters for the solution in S5 are a spraying distance of 80 mm and a spraying rate of 60 mm / s.

3. The paper-wrapped copper flat wire according to claim 1, characterized in that, The rare earth oxide in S3 is one or more of cerium oxide, lanthanum oxide, and praseodymium oxide.

4. The paper-wrapped copper flat wire according to claim 1, characterized in that, The powder obtained by grinding in S3 has a particle size of 300~400 mesh.

5. The paper-wrapped copper flat wire according to claim 1, characterized in that, The laser irradiation parameters in S5 are: laser power 250W, temperature 80℃, and irradiation time 30min.

6. The paper-wrapped copper flat wire according to claim 1, characterized in that, The thickness of the modified aramid insulating paper layer obtained by S6 is 0.8~1.2mm.

7. A method for preparing paper-insulated copper flat wire, based on the paper-insulated copper flat wire according to any one of claims 1 to 6, characterized in that, The paper-insulated copper flat wire preparation process is as follows. S71: The copper wire is drawn into wires by a flat die on a wire drawing machine, and then rolled into flat copper wires by a rolling die on the wire drawing machine. S72: The copper flat wire that has been drawn and rolled is transferred into the annealing furnace and annealed at a speed of 150 m / min under a nitrogen atmosphere. S73: The annealed copper flat wire is ultrasonically cleaned using an ultrasonic cleaner to obtain clean copper flat wire. S74: Use nitrogen gas at 50℃ at a flow rate of 8m / s to purge the copper flat wire to obtain a dry and clean copper flat wire. S75: The modified aramid insulating paper layer is wrapped around the copper flat wire to obtain the final product, paper-wrapped copper flat wire.

8. The method for preparing paper-covered copper flat wire according to claim 7, characterized in that, The thickness of the copper flat wire obtained in S71 is 2.7 mm.

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