Ceramic wire capable of being sintered at low temperature and preparation method thereof

Abstract

The invention discloses a low-temperature sintering ceramic wire and a preparation method thereof, the low-temperature sintering ceramic wire comprises a conductor, a first insulating layer and a second insulating layer, the first insulating layer and the second insulating layer sequentially wrap the surface of the conductor, the first insulating layer is located between the conductor and the second insulating layer, and the second insulating layer is located between the conductor and the second insulating layer. The first insulating layer and the second insulating layer are subjected to a double-layer co-extrusion process to obtain the low-temperature sintered ceramic wire; the double-layer co-extrusion insulating layer comprises a LiMgPO4-based ceramic layer and a silicon rubber layer which are arranged from inside to outside; the preparation method of the ceramic layer comprises the following steps: S1, weighing 15 parts of lithium carbonate, 20 parts of magnesium oxide and 60 parts of ammonium dihydrogen phosphate, respectively adding the materials into a cosolvent, and carrying out ball milling for 24 hours; and drying the mixed powder at the temperature of 80 DEG C, and calcining at the temperature of 900 DEG C for 4 hours to obtain LiMgPO4 powder. According to the invention, the LiMgPO4-based ceramic is added in the first insulating layer, so that the ceramic wire capable of being sintered at low temperature has better anti-aging and high-temperature-resistant effects, is insulated, waterproof and anti-permeation, is particularly suitable for being used in outdoor high-temperature and low-temperature environments, can ensure the safety in use and prolong the service life, and can be prevented from being damaged even in an external severe environment. And long-term use and no deformation can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of electric wires, in particular to a ceramic electric wire capable of being sintered at a low temperature and a preparation method thereof. Background Art

[0002] Low-temperature sintered ceramic wire refers to the wire produced by applying low-temperature sintered ceramic polymer materials composed of low-temperature sintered ceramic materials and polymer materials to insulation and sheath. It has the characteristics of good electrical insulation performance, high temperature resistance, corrosion resistance, etc. Low-temperature sintered ceramic polymer materials are a new type of composite polymer material that can be vitrified below 1100°C. It maintains all the characteristics of ordinary insulation at room temperature and is converted into inorganic ceramic materials when encountering high temperatures. This material has the advantages of insulation, heat insulation, fire insulation, earthquake resistance, and low thermal weight loss. In the event of a fire, the "ceramicized" hard shell can play a good role in flame retardancy, fire resistance, fire prevention, and fire insulation, effectively ensuring the smooth flow of the line. The vitrification temperature of existing ceramic wires mostly exceeds 1100°C, which leads to the fact that when the combustion temperature is low, the internal structure of the ceramic body transformed from ceramic silicone rubber is loose, the vitrification strength is not high, and it is difficult to protect the copper conductor inside the wire and cable. In order to solve this problem, we have proposed a low-temperature sintered ceramic wire.

[0003] The present invention is proposed in view of the above problems. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a ceramic wire that can be sintered at a low temperature and a preparation method thereof, so as to solve the problems mentioned in the background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions.

[0006] The present invention provides a low-temperature sinterable ceramic wire and a preparation method thereof, comprising a conductor, a first insulating layer and a second insulating layer, wherein the first insulating layer and a sheath are sequentially wrapped around the surface of the conductor, the first insulating layer is located between the conductor and the second insulating layer, and the first insulating layer and the second insulating layer are subjected to a double-layer co-extrusion process to obtain a low-temperature sintered ceramic wire.

[0007] A method for preparing a ceramic wire that can be sintered at a low temperature comprises the following steps:

[0008] S1, weighing 15 parts of lithium carbonate, 25 parts of magnesium oxide, and 60 parts of ammonium dihydrogen phosphate, respectively adding them to a co-solvent, and ball milling for 24 hours; the mixed powder is dried at 80°C, and then calcined at 900°C for 4 hours to obtain LiMgPO4 powder;

[0009] S2, after the silicone rubber is heated until it is completely melted, it is placed in an open mill, and LiMgPO4 powder, calcium titanate, potassium molybdate, nano-silicon dioxide, hydroxy silicone oil, and a coupling agent are added in sequence, and the mixture is mixed by friction and heating of the roller surface to obtain a mixed rubber;

[0010] S3, adding a vulcanizing agent to the obtained mixed rubber for vulcanization to obtain a ceramic silicone rubber vulcanizate that can be sintered at a low temperature, the vulcanization temperature condition is 150-180° C., the first vulcanization time is 15-20 minutes, and the second vulcanization time is 1-2 hours;

[0011] S4. The ceramic silicone rubber vulcanizate that can be sintered at low temperature is pressed at 15 MPa and 150-200° C. for 30-90 min to prepare low-temperature sintered ceramic silicone rubber.

[0012] Preferably, the silicone rubber is one or more of ethylene propylene rubber, methyl phenyl vinyl silicone rubber, dimethyl silicone rubber, and methyl vinyl silicone rubber.

[0013] Preferably, the vulcanizing agent is one of benzoyl peroxide, quinone oxime compounds, polysulfide polymers, ethyl formate, and maleimide derivatives.

[0014] Preferably, the low-temperature sintering temperature of the low-temperature sinterable ceramic silicone rubber is 300-500°C.

[0015] Preferably, the first insulating layer comprises the following components: 60-80 parts of silicone rubber, 15-25 parts of nano-silicon dioxide, 0.5-1 parts of cosolvent, 3-8 parts of coupling agent, 2-4 parts of vulcanizer, 5-10 parts of hydroxy silicone oil, 25-45 parts of LiMgPO4 powder, 10-15 parts of calcium titanate, and 20-40 parts of potassium molybdate.

[0016] Preferably, the first insulating layer comprises the following components: 65-75 parts of silicone rubber, 18-22 parts of nano-silicon dioxide, 0.7-0.9 parts of cosolvent, 5-7 parts of coupling agent, 3-4 parts of vulcanizer, 6-8 parts of hydroxy silicone oil, 20-35 parts of LiMgPO4 powder, 8-15 parts of calcium titanate, and 20-25 parts of potassium molybdate.

[0017] Preferably, the first insulating layer comprises the following components: 70 parts of silicone rubber, 20 parts of nano-silicon dioxide, 0.8 parts of cosolvent, 6 parts of coupling agent, 3.5 parts of vulcanizer, 7 parts of hydroxy silicone oil, 25 parts of LiMgPO4 powder, 15 parts of calcium titanate, and 25 parts of potassium molybdate.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The ceramic layer gradually formed on the surface of ceramic silicone rubber during the sintering process will play a role in heat insulation. The sintering temperature is mostly over 1100℃. In the event of a small fire, the silicone rubber cannot be completely vitrified, resulting in too low strength of the ceramic body to protect the internal copper wire. Therefore, a ceramic silicone rubber material that can be sintered at low temperature was designed and prepared, in which LiMgPO4, calcium titanate, and potassium molybdate reacted eutectically in the presence of a cosolvent and a coupling agent to generate a new microcrystalline phase, so that the ceramic silicone rubber can form a hard and dense ceramic layer at 300-500℃;

[0020] LiMgPO4-based ceramics are a new material system that can be applied to low-temperature co-fired ceramic technology due to their low inherent sintering temperature, high quality factor, low dielectric constant and bulk density, and good chemical compatibility with Ag. The first insulating layer containing LiMgPO4-based ceramics has better anti-aging and high-temperature resistance, and is waterproof and resistant to penetration. It is particularly suitable for cables used in outdoor high and low temperature environments. It can ensure safety during use and extend the service life. Even in harsh external environments, it can be used for a long time without deformation. It has a solid texture and strong protection against external electromagnetic interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a cross-sectional view of a ceramic wire that can be sintered at a low temperature according to the present invention;

[0022] Figure 2 The present invention is a flowchart of the steps of preparing a low temperature sinterable ceramic wire.

[0023] In the figure: 1, conductor; 2, first insulating layer; 3, second insulating layer. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0025] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0026] like Figure 1-2As shown, a low-temperature sinterable ceramic wire and a preparation method thereof, comprising a conductor 1, a first insulating layer 2 and a second insulating layer 3, wherein the first insulating layer 2 and the sheath 3 are sequentially wrapped on the surface of the conductor, the first insulating layer 2 is located between the conductor 1 and the second insulating layer 3, and the first insulating layer 2 and the second insulating layer 3 are subjected to a double-layer co-extrusion process to obtain a low-temperature sintered ceramic wire;

[0027] Double-layer co-extrusion technology is a production process that extrude two layers of plastic materials simultaneously through two extruders, and compound the two layers of extruded plastic materials together through a special die head; double-layer co-extrusion technology can comprehensively utilize the characteristics of two different plastic materials. By customizing different extruders and molds, the two plastic materials are extruded and compounded, so that the performance of the composite product is better than that of a single material.

[0028] A method for preparing a ceramic wire that can be sintered at a low temperature comprises the following steps:

[0029] S1, weighing 15 parts of lithium carbonate, 25 parts of magnesium oxide, and 60 parts of ammonium dihydrogen phosphate, respectively adding them to a co-solvent, and ball milling for 24 hours; the mixed powder is dried at 80°C, and then calcined at 900°C for 4 hours to obtain LiMgPO4 powder;

[0030] S2, after the silicone rubber is heated until it is completely melted, it is placed in an open mill, and LiMgPO4 powder, calcium titanate, potassium molybdate, nano-silicon dioxide, hydroxy silicone oil, and a coupling agent are added in sequence, and the mixture is mixed by friction and heating of the roller surface to obtain a mixed rubber;

[0031] S3, adding a vulcanizing agent to the obtained mixed rubber for vulcanization to obtain a ceramic silicone rubber vulcanizate that can be sintered at a low temperature, the vulcanization temperature condition is 150-180° C., the first vulcanization time is 15-20 minutes, and the second vulcanization time is 1-2 hours;

[0032] S4. The ceramic silicone rubber vulcanizate that can be sintered at low temperature is pressed at 15 MPa and 150-200° C. for 30-90 min to prepare low-temperature sintered ceramic silicone rubber.

[0033] The silicone rubber is one or more of ethylene propylene rubber, methyl phenyl vinyl silicone rubber, dimethyl silicone rubber, and methyl vinyl silicone rubber, and preferably methyl phenyl vinyl silicone rubber.

[0034] The vulcanizing agent is one of benzoyl peroxide, quinone oxime compound, polysulfide polymer, ethyl formate, and maleimide derivative, preferably polysulfide polymer.

[0035] The low-temperature sintering temperature of the low-temperature sinterable ceramic silicone rubber is below 300-500°C.

[0036] The first insulating layer 2 includes the following components: 60-80 parts of silicone rubber, 15-25 parts of nano silicon dioxide, 0.5-1 parts of cosolvent, 3-8 parts of coupling agent, 2-4 parts of vulcanizer, 5-10 parts of hydroxy silicone oil, 25-40 parts of LiMgPO4 powder, 10-15 parts of calcium titanate, and 20-40 parts of potassium molybdate.

[0037] In another embodiment, the first insulating layer 2 includes the following components: 65-75 parts of silicone rubber, 18-22 parts of nano-silicon dioxide, 0.7-0.9 parts of cosolvent, 5-7 parts of coupling agent, 3-4 parts of vulcanizer, 6-8 parts of hydroxy silicone oil, 20-35 parts of LiMgPO4 powder, 8-15 parts of calcium titanate, and 20-25 parts of potassium molybdate.

[0038] In another embodiment, the first insulating layer 2 includes the following components: 70 parts of silicone rubber, 20 parts of nano-silicon dioxide, 0.8 parts of cosolvent, 6 parts of coupling agent, 3.5 parts of vulcanizer, 7 parts of hydroxy silicone oil, 25 parts of LiMgPO4 powder, 15 parts of calcium titanate, and 25 parts of potassium molybdate.

[0039] In summary: the ceramic layer gradually formed on the surface of ceramic silicone rubber during the sintering process will play a role in heat insulation. The sintering temperature is mostly over 1100℃. In the event of a small fire, the silicone rubber cannot be completely vitrified, resulting in too low strength of the ceramic body to protect the internal copper wire. Therefore, a ceramic silicone rubber material that can be sintered at low temperature was designed and prepared, in which LiMgPO4, calcium titanate, and potassium molybdate reacted eutectically in the presence of a cosolvent and a coupling agent to generate a new microcrystalline phase, so that the ceramic silicone rubber can form a hard and dense ceramic layer at 300-500℃;

[0040] LiMgPO4-based ceramics are a new material system that can be applied to low-temperature co-fired ceramic technology due to their low inherent sintering temperature, high quality factor, low dielectric constant and bulk density, and good chemical compatibility with Ag. The first insulating layer 2 containing LiMgPO4-based ceramics has better anti-aging and high-temperature resistance, and is waterproof and resistant to penetration. It is particularly suitable for cables to be used in outdoor high and low temperature environments, and can ensure safety during use and extend the service life. Even in harsh external environments, it can be used for a long time without deformation, has a solid texture, and has a strong protective effect against external electromagnetic interference.

[0041] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A ceramic wire capable of being sintered at low temperature, characterized in that: The invention comprises a conductor (1), a first insulating layer (2) and a second insulating layer (3), wherein the first insulating layer (2) and the second insulating layer (3) are sequentially wrapped around the surface of the conductor, the first insulating layer (2) is located between the conductor (1) and the second insulating layer (3), and the first insulating layer (2) and the second insulating layer (3) are subjected to a double-layer co-extrusion process to obtain a low-temperature sintered ceramic wire.

2. A method for preparing the low temperature sinterable ceramic wire according to claim 1, characterized in that: The first insulating layer comprises the following preparation steps: S1, weighing 15 parts of lithium carbonate, 25 parts of magnesium oxide, and 60 parts of ammonium dihydrogen phosphate, respectively adding them to a co-solvent, and ball milling for 24 hours; the mixed powder is dried at 80°C, and then calcined at 900°C for 4 hours to obtain LiMgPO4 powder; S2, after the silicone rubber is heated until it is completely melted, it is placed in an open mill, and LiMgPO4 powder, calcium titanate, potassium molybdate, nano-silicon dioxide, hydroxy silicone oil, and a coupling agent are added in sequence, and the mixture is mixed by friction and heating of the roller surface to obtain a mixed rubber; S3, adding a vulcanizing agent to the obtained mixed rubber for vulcanization to obtain a ceramic silicone rubber vulcanizate that can be sintered at a low temperature, the vulcanization temperature condition is 150-180° C., the first vulcanization time is 15-20 minutes, and the second vulcanization time is 1-2 hours; S4. The ceramic silicone rubber vulcanizate that can be sintered at low temperature is pressed at 15 MPa and 150-200° C. for 30-90 min to prepare low-temperature sintered ceramic silicone rubber.

3. The low temperature sinterable ceramic wire according to claim 1, characterized in that: The material used for the second insulating layer is one or more of ethylene propylene rubber, methyl phenyl vinyl silicone rubber, dimethyl silicone rubber, and methyl vinyl silicone rubber.

4. A low temperature sinterable ceramic wire and a method for preparing the same according to claim 2, characterized in that: The silicone rubber is one or more of ethylene propylene rubber, methyl phenyl vinyl silicone rubber, dimethyl silicone rubber, and methyl vinyl silicone rubber.

5. The low temperature sinterable ceramic wire and the preparation method thereof according to claim 2, characterized in that: The vulcanizing agent is one of benzoyl peroxide, quinone oxime compound, polysulfide polymer, ethyl formate, and maleimide derivative.

6. A low temperature sinterable ceramic wire and a method for preparing the same according to claim 2, characterized in that: The low-temperature sintering temperature of the ceramic silicone rubber capable of low-temperature sintering is 300-500°C.

7. The low temperature sinterable ceramic wire according to claim 1, characterized in that: The first insulating layer comprises the following components: 60-80 parts of silicone rubber, 15-25 parts of nano silicon dioxide, 0.5-1 parts of cosolvent, 3-8 parts of coupling agent, 2-4 parts of vulcanizer, 5-10 parts of hydroxy silicone oil, 25-45 parts of LiMgPO4 powder, 10-15 parts of calcium titanate, and 20-40 parts of potassium molybdate.

8. The low temperature sinterable ceramic wire according to claim 1, characterized in that: The first insulating layer comprises the following components: 65-75 parts of silicone rubber, 18-22 parts of nano silicon dioxide, 0.7-0.9 parts of cosolvent, 5-7 parts of coupling agent, 3-4 parts of vulcanizer, 6-8 parts of hydroxy silicone oil, 20-35 parts of LiMgPO4 powder, 8-15 parts of calcium titanate, and 20-25 parts of potassium molybdate.

9. The low temperature sinterable ceramic wire according to claim 1, characterized in that: The first insulating layer includes the following components: 70 parts of silicone rubber, 20 parts of nano-silicon dioxide, 0.8 parts of cosolvent, 6 parts of coupling agent, 3.5 parts of vulcanizer, 7 parts of hydroxy silicone oil, 25 parts of LiMgPO4 powder, 15 parts of calcium titanate, and 25 parts of potassium molybdate.

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