High-conductivity sensor connecting strip material and continuous extrusion process thereof

Abstract

The invention relates to the technical field of conductive material manufacturing, in particular to a high-conductivity sensor connecting strip material and a continuous extrusion process thereof. 3.3 to 4.5 parts of pretreated copper powder; 5.5 to 6.5 parts of conductive filler; 1.1 to 1.4 parts of an antioxidant; 2.8 to 3.5 parts of a dispersant; 3.9 to 5 parts of a coupling agent; wherein the resin matrix is prepared from an ethylene-vinyl acetate copolymer, an acrylonitrile-styrene-acrylate terpolymer and polybutylene terephthalate, the pretreated copper powder is obtained after copper powder is subjected to ball milling, and the conductive filler is obtained by mixing graphene oxide, carbon fibers and few-layer molybdenum disulfide. The sensor connecting strip material with high conductivity and high tensile strength is obtained by uniformly mixing the raw materials at a high speed, putting the mixture into a double-screw extruder, performing extrusion molding through a mold and performing cooling shaping, and has a wide application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of conductive material manufacturing, in particular to a high-conductivity sensor connecting strip material and a continuous extrusion process thereof. Background Art

[0002] A sensor is a device that detects and senses external signals, physical conditions, or chemical compositions, and converts this information into electrical signals or other desired output formats to meet the requirements of information transmission, processing, storage, display, recording, and control. Like human senses, it is the primary link in automatic detection and control.

[0003] In terms of their operating principles, sensors convert signals based on various physical, chemical, and biological effects. Examples include temperature sensors that utilize the thermoelectric effect and magnetic sensors that utilize the Hall effect. They typically consist of a sensitive element, a conversion element, a measurement circuit, and an auxiliary power supply. In terms of applications, sensors are widely used in a wide range of fields, including industrial production, space exploration, ocean exploration, environmental protection, resource surveys, medical diagnosis, bioengineering, and even cultural heritage preservation. For example, in automobiles, there are temperature and pressure sensors for monitoring engine operating conditions, and collision sensors for safety systems. In smart homes, there are light and humidity sensors that sense the environment and implement automatic control.

[0004] The sensor connector strip is a component used to connect the sensor to other devices or components to achieve signal transmission and mechanical fixation. The choice of its material has a significant impact on the performance, reliability and service life of the sensor. Therefore, its high conductivity is very important for the sensor.

[0005] In the prior art, research on the conductivity of sensor connecting strip materials is relatively common, but its mechanical properties such as tensile strength need to be further improved.

[0006] Therefore, according to the above-mentioned related technologies, it is urgent to develop highly conductive sensor connecting strip materials and continuous extrusion processes thereof. Summary of the Invention

[0007] In view of this, the purpose of the present invention is to propose a highly conductive sensor connecting strip material and a continuous extrusion process thereof, so as to solve the problems of poor conductivity and low tensile strength of the connecting strip material in the prior art.

[0008] Based on the above objectives, the present invention provides a highly conductive sensor connecting strip material and a continuous extrusion process thereof.

[0009] High conductivity sensor connecting strip material, including the following raw materials in parts by weight:

[0010] Resin matrix 60-66 parts; pretreated copper powder 3.3-4.5 parts; conductive filler 5.5-6.5 parts; antioxidant 1.1-1.4 parts; dispersant 2.8-3.5 parts; coupling agent 3.9-5 parts;

[0011] The resin matrix is ​​obtained by mixing ethylene-vinyl acetate copolymer, acrylonitrile-styrene-acrylate terpolymer and polybutylene terephthalate in a mass ratio of 2-4.2:1.4-3.5:5-7;

[0012] The pretreated copper powder is prepared by ball milling copper powder and a composite lubricant;

[0013] The particle size of the pretreated copper powder is 1-6 μm;

[0014] The composite lubricant is obtained by mixing stearic acid and nano-molybdenum disulfide freeze-dried powder in a mass ratio of 23-28:5.5-7.2;

[0015] The conductive filler is obtained by mixing graphene oxide, carbon fiber and few-layer molybdenum disulfide in a mass ratio of 8-11.3:5-7:2.2-3.5.

[0016] Preferably, the preparation method of the few-layer molybdenum disulfide is as follows:

[0017] Molybdenum disulfide was added to a 95% by mass ethanol solution, stirred evenly, and poured into a jet cavitation device. The parameters were set to obtain a suspension, which was then dried at 75-85°C to obtain a few-layer molybdenum disulfide.

[0018] Preferably, the molybdenum disulfide and ethanol solution are used in a ratio of 1-1.5 g: 100-150 mL;

[0019] The pressure in the parameters is 150000-170000 KPa, and the temperature of the circulating cooling water bath is 8-13°C.

[0020] Preferably, the preparation method of the nano molybdenum disulfide freeze-dried powder is as follows:

[0021] Step A1. Sodium dodecylbenzenesulfonate was added to deionized water and ultrasonically dispersed until completely dissolved to obtain a mixed solution A; sodium molybdate and thiourea were added to deionized water and ultrasonically dispersed to obtain mixed solutions B and C;

[0022] Step A2. Mixture B and mixture C were added to mixture A in sequence, stirred evenly, and the pH of the solution was adjusted to 2-3 with hydrochloric acid. The mixture was then placed in a 50 mL polytetrafluoroethylene-lined autoclave, sealed, and placed in a constant temperature oven for heat treatment. After the reaction, the mixture was cooled to room temperature and washed with ethanol to obtain a nano-molybdenum disulfide precursor solution.

[0023] Step A3. Place the nano-molybdenum disulfide precursor solution in a culture dish and freeze it in a freeze dryer at -50°C for 30-40 minutes to obtain nano-molybdenum disulfide freeze-dried powder.

[0024] Preferably, the ratio of sodium dodecylbenzenesulfonate to deionized water in step A1 is 3.5-5 g: 20-30 mL;

[0025] The usage ratio of sodium molybdate and deionized water in step A2 is 0.42-0.5 g:5 mL.

[0026] Preferably, the ratio of thiourea to deionized water in step A2 is 0.28-0.38 g:5 mL;

[0027] The volume ratio of the mixed solution B, mixed solution C and mixed solution A is 20-25:5-5.5:5-5.5; the temperature during the heat treatment is 175-188° C. and the time is 22-24 hours.

[0028] Preferably, the preparation method of the graphene oxide is as follows:

[0029] Graphite powder and concentrated sulfuric acid were added to a beaker, mixed and stirred in an ice bath for 22-24 hours, and then potassium permanganate and deionized water were added while stirring. After stirring evenly, 30% by mass hydrogen peroxide was added, and the mixture was allowed to stand for 24 hours before centrifugation and washing. The mixture was then added to 10% by mass hydrochloric acid and stirred for 10-15 minutes. After centrifugation and washing, the mixture was dialyzed for 48 hours to obtain graphene oxide.

[0030] The usage ratio of the graphite powder, concentrated sulfuric acid, potassium permanganate, deionized water, hydrogen peroxide and hydrochloric acid is 24-28 g: 380-430 mL: 25-30 g: 800-850 mL: 400-500 mL: 500-550 mL.

[0031] Preferably, the preparation method of the pretreated copper powder is as follows:

[0032] Under a nitrogen atmosphere, tungsten steel balls, copper powder and composite lubricant are sequentially added to a ball milling jar, and the ball mill is started to perform ball milling. After the ball milling operation is completed, the pretreated copper powder is filtered to obtain the pretreated copper powder;

[0033] The mass ratio of the tungsten steel ball, copper powder and composite lubricant is 27-33:1-1.4:0.1-0.14.

[0034] Preferably, the antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate;

[0035] The dispersant is obtained by mixing isopropyl tristearate titanate and stearic acid in a mass ratio of 5-8:2.4-4.5;

[0036] The coupling agent is γ-methacryloxypropyltrimethoxysilane.

[0037] The continuous extrusion process of the highly conductive sensor connector strip material comprises the following steps:

[0038] Step S1. Add a conductive filler, a coupling agent, a pretreated copper powder, an antioxidant, and a dispersant to the resin matrix, place it in a high-speed mixer, and continue to mix thoroughly at a temperature of 100-110°C and a speed of 1300-1500 r / min for 15-25 minutes to obtain a mixture 1;

[0039] Step S2. Place the mixed material 1 in a twin-screw extruder and set the temperature to: 160-170°C in zone 1, 170-180°C in zone 2, 180-190°C in zone 3, 190-200°C in zone 4, and 200-210°C in zone 5, with a screw speed of 200-300 r / min. Then, the mixed material 1 is extruded through a mold and cooled in a cooling water tank to obtain a connecting strip material.

[0040] Beneficial effects of the present invention:

[0041] The present invention provides a highly conductive sensor connecting strip material and a continuous extrusion process thereof. The present invention comprises the following steps: a resin matrix, pretreated copper powder, conductive filler, antioxidant, dispersant, and coupling agent are mixed at high speed, placed in a twin-screw extruder, and then extruded through a die, cooled, and shaped to obtain a connecting strip material having high conductivity and high tensile strength.

[0042] Among them, the resin matrix is ​​prepared from ethylene-vinyl acetate copolymer, acrylonitrile-styrene-acrylate terpolymer and polybutylene terephthalate. By mixing the three resin materials, the mechanical properties of the matrix material, such as tensile strength, are further improved; and in the conductive filler, the two-dimensional structure of a few-layer molybdenum disulfide can form a dense network with carbon fiber and graphene oxide, which can not only enhance the overall conductivity of the connecting strip material, but also relieve stress concentration, thereby improving the mechanical properties of the material; in the pretreated copper powder, the lubricant obtained by mixing stearic acid and nano-molybdenum disulfide freeze-dried powder can effectively inhibit the oxidation of copper powder and improve the dispersibility of copper powder while improving the ball milling efficiency. Compared with the existing technology, it has broad application prospects. DETAILED DESCRIPTION

[0043] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0044] The sources and properties of some of the raw materials used in the present invention are as follows:

[0045] Molybdenum disulfide was purchased from Wuhan Chujiang Haoyu Chemical Technology Development Co., Ltd.; sodium molybdate was purchased from Jinan Jinhao Chemical Co., Ltd.; thiourea was purchased from Jinan Century Tongda Chemical Co., Ltd.; graphite powder was purchased from Dongguan Jiecheng Graphite Products Co., Ltd.; and copper powder was purchased from Shijiazhuang Jingyuan Powder Materials Co., Ltd.

[0046] Example 1: A continuous extrusion process for a highly conductive sensor connecting strip material, comprising the following steps:

[0047] S1. Add 1 g of molybdenum disulfide to 100 mL of 95% ethanol solution, stir thoroughly, and pour into a jet cavitation device with the following parameters: pressure of 150,000 kPa and circulating cooling water bath temperature of 8°C. The resulting suspension was then dried at 75°C to obtain a few-layer molybdenum disulfide.

[0048] S2. 3.5 g of sodium dodecylbenzenesulfonate was added to 20 mL of deionized water and ultrasonically dispersed until completely dissolved to obtain a mixed solution A; 0.42 g of sodium molybdate and 0.28 g of thiourea were added to 5 mL of deionized water and ultrasonically dispersed to obtain mixed solutions B and C;

[0049] S3. 20-25mL of mixed solution B and 5mL of mixed solution C were successively added to 5mL of mixed solution A, stirred evenly, and the pH of the solution was adjusted to 2 with hydrochloric acid, and then placed in a polytetrafluoroethylene-lined autoclave containing 50mL, sealed, and placed in a constant temperature oven at 175 ° C for 22h. After the reaction, the mixture was cooled to room temperature and washed with ethanol to obtain a nano-molybdenum disulfide precursor solution;

[0050] S4. The nano-molybdenum disulfide precursor solution was placed in a culture dish and placed on a -50°C freeze dryer for 30 minutes to obtain a freeze-dried powder of nano-molybdenum disulfide;

[0051] S5. 24 g of graphite powder and 380 mL of concentrated sulfuric acid were added to a beaker and stirred in an ice bath for 22 h. 25 g of potassium permanganate and 800 mL of deionized water were then added while stirring. After stirring, 400 mL of 500 mL of 30% hydrogen peroxide was added, and the mixture was allowed to stand for 24 h before centrifugation and washing. The mixture was then added to 10% hydrochloric acid and stirred for 10 min. The mixture was centrifuged, washed, and dialyzed for 48 h to obtain graphene oxide.

[0052] S6. 23 g of stearic acid and 5.5 g of freeze-dried nano-molybdenum disulfide powder were mixed to obtain a composite lubricant; under a nitrogen atmosphere, 27 g of tungsten steel balls, 1 g of copper powder, and 0.1 g of the composite lubricant were added to a ball mill, and the ball mill was started for ball milling. After the ball milling operation was completed, the pretreated copper powder was filtered;

[0053] S7. 8g of graphene oxide, 5g of carbon fiber and 2.2g of a few-layer molybdenum disulfide were mixed to obtain a conductive filler; 2g of ethylene-vinyl acetate copolymer, 1.4g of acrylonitrile-styrene-acrylate terpolymer and 5g of polybutylene terephthalate were mixed to obtain a resin matrix;

[0054] S8. To 60g of the resin matrix was added 5.5g of a conductive filler, 3.9g of a coupling agent, 3.3g of pretreated copper powder, 1.1g of an antioxidant and 2.8g of a dispersant, and placed in a high-speed mixer at a temperature of 100°C and a speed of 1300r / min and continued to mix thoroughly for 15min to obtain a mixture 1;

[0055] S9. Mixture 1 is placed in a twin-screw extruder and the temperatures are set to: 160°C in zone 1, 170°C in zone 2, 180°C in zone 3, 190°C in zone 4, and 200°C in zone 5. The screw speed is 200 r / min. The mixture is then extruded through a mold and cooled in a cooling water tank to obtain a connecting strip material.

[0056] Example 2: A continuous extrusion process for a highly conductive sensor connecting strip material, comprising the following steps:

[0057] S1. Add 1.1 g of molybdenum disulfide to 110 mL of 95% ethanol solution, stir well, and pour into a jet cavitation device with the following parameters: pressure of 150,000 kPa and circulating cooling water bath temperature of 9°C. The resulting suspension was then dried at 77°C to obtain a few-layer molybdenum disulfide.

[0058] S2. 4 g of sodium dodecylbenzenesulfonate was added to 22 mL of deionized water and ultrasonically dispersed until completely dissolved to obtain a mixed solution A; 0.44 g of sodium molybdate and 0.3 g of thiourea were added to 5 mL of deionized water and ultrasonically dispersed to obtain mixed solutions B and C;

[0059] S3. 22 mL of mixed solution B and 5.1 mL of mixed solution C were successively added to 5.1 mL of mixed solution A, stirred evenly, and the pH of the solution was adjusted to 2 with hydrochloric acid, then placed in a polytetrafluoroethylene-lined autoclave containing 50 mL, sealed, and placed in a constant temperature oven at 178 ° C for 23 h. After the reaction, the mixture was cooled to room temperature and washed with ethanol to obtain a nano-molybdenum disulfide precursor solution;

[0060] S4. The nano-molybdenum disulfide precursor solution was placed in a culture dish and placed on a -50°C freeze dryer for 32 minutes to obtain a freeze-dried powder of nano-molybdenum disulfide;

[0061] S5. 25 g of graphite powder and 390 mL of concentrated sulfuric acid were added to a beaker and stirred in an ice bath for 23 h. 26 g of potassium permanganate and 810 mL of deionized water were then added while stirring. After stirring, 420 mL of 510 mL of 30% hydrogen peroxide was added and allowed to stand for 24 h. The mixture was then centrifuged and washed. The mixture was then added to 10% hydrochloric acid and stirred for 11 min. The mixture was centrifuged and washed and then dialyzed for 48 h to obtain graphene oxide.

[0062] S6. Under a nitrogen atmosphere, 28 g of tungsten steel balls, 1.1 g of copper powder, and 0.11 g of a composite lubricant were added to a ball mill, and the ball mill was started for milling. After the milling operation was completed, the pretreated copper powder was filtered;

[0063] S7. 24 g of stearic acid and 5.8 g of freeze-dried nano-molybdenum disulfide powder were mixed to obtain a composite lubricant; 8.5 g of graphene oxide, 5.5 g of carbon fiber and 2.5 g of few-layer molybdenum disulfide were mixed to obtain a conductive filler; 2.5 g of ethylene-vinyl acetate copolymer, 1.8 g of acrylonitrile-styrene-acrylate terpolymer and 5.5 g of polybutylene terephthalate were mixed to obtain a resin matrix;

[0064] S8. To 62g of the resin matrix was added 5.8g of a conductive filler, 4.2g of a coupling agent, 3.7g of pretreated copper powder, 1.2g of an antioxidant, and 3g of a dispersant, and placed in a high-speed mixer at a temperature of 103°C and a speed of 1400r / min and continued to mix thoroughly for 17min to obtain a mixture 1;

[0065] S9. Mixture 1 is placed in a twin-screw extruder and the temperatures are set to: 162°C in zone 1, 172°C in zone 2, 182°C in zone 3, 192°C in zone 4, and 202°C in zone 5. The screw speed is 220 r / min. Mixture 1 is then extruded through a mold and cooled in a cooling water tank to obtain a connecting strip material.

[0066] Example 3: A continuous extrusion process for a highly conductive sensor connecting strip material, comprising the following steps:

[0067] S1. Add 1.3 g of molybdenum disulfide to 120 mL of 95% ethanol solution, stir well, and pour into a jet cavitation device with the following parameters: pressure of 160,000 kPa and circulating cooling water bath temperature of 10°C. The resulting suspension was then dried at 80°C to obtain a few-layer molybdenum disulfide.

[0068] S2. 4.5 g of sodium dodecylbenzenesulfonate was added to 25 mL of deionized water and ultrasonically dispersed until completely dissolved to obtain a mixed solution A; 0.45 g of sodium molybdate and 0.32 g of thiourea were added to 5 mL of deionized water and ultrasonically dispersed to obtain mixed solutions B and C;

[0069] S3. 22 mL of mixed solution B and 5.2 mL of mixed solution C were successively added to 5.2 mL of mixed solution A, stirred evenly, and the pH of the solution was adjusted to 3 with hydrochloric acid, then placed in a polytetrafluoroethylene-lined autoclave containing 50 mL, sealed, and placed in a constant temperature oven at 182 ° C for 23 h. After the reaction, the mixture was cooled to room temperature and washed with ethanol to obtain a nano-molybdenum disulfide precursor solution;

[0070] S4. The nano-molybdenum disulfide precursor solution was placed in a culture dish and placed on a -50°C freeze dryer for 35 minutes to obtain a freeze-dried powder of nano-molybdenum disulfide;

[0071] S5. 25 g of graphite powder and 400 mL of concentrated sulfuric acid were added to a beaker and stirred in an ice bath for 22-24 h. 27 g of potassium permanganate and 820 mL of deionized water were then added while stirring. After stirring, 450 mL of 520 mL of 30% hydrogen peroxide was added, and the mixture was allowed to stand for 24 h, centrifuged, washed, and then added to 10% hydrochloric acid, stirred for 12 min, centrifuged, washed, and dialyzed for 48 h to obtain graphene oxide.

[0072] S6. Under a nitrogen atmosphere, 30 g of tungsten steel ball, 1.2 g of copper powder and 0.12 g of composite lubricant were added to the ball mill jar, and the ball mill was started for ball milling. After the ball milling operation was completed, the pretreated copper powder was filtered;

[0073] S7. 25 g of stearic acid and 6.5 g of freeze-dried nano-molybdenum disulfide powder were mixed to obtain a composite lubricant; 9 g of graphene oxide, 6 g of carbon fiber and 2.8 g of few-layer molybdenum disulfide were mixed to obtain a conductive filler; 3 g of ethylene-vinyl acetate copolymer, 2.5 g of acrylonitrile-styrene-acrylate terpolymer and 6 g of polybutylene terephthalate were mixed to obtain a resin matrix;

[0074] S8. To 64g of the resin matrix was added 6g of conductive filler, 4.5g of coupling agent, 3.8g of pretreated copper powder, 1.3g of antioxidant and 3.3g of dispersant, placed in a high-speed mixer at a temperature of 105 ° C and continued to mix thoroughly at a speed of 1400r / min for 20min to obtain a mixture 1;

[0075] S9. Mixture 1 is placed in a twin-screw extruder and the temperatures are set to: 165°C in zone 1, 175°C in zone 2, 185°C in zone 3, 195°C in zone 4, and 205°C in zone 5. The screw speed is 250 r / min. Mixture 1 is then extruded through a mold and cooled in a cooling water tank to obtain a connecting strip material.

[0076] Example 4: A continuous extrusion process for a highly conductive sensor connecting strip material, comprising the following steps:

[0077] S1. Add 1.4 g of molybdenum disulfide to 140 mL of 95% ethanol solution, stir well, and pour into a jet cavitation device with the following parameters: pressure of 160,000 kPa and circulating cooling water bath temperature of 12°C. The resulting suspension was then dried at 83°C to obtain a few-layer molybdenum disulfide.

[0078] S2. 4.7 g of sodium dodecylbenzenesulfonate was added to 28 mL of deionized water and ultrasonically dispersed until completely dissolved to obtain a mixed solution A; 0.48 g of sodium molybdate and 0.35 g of thiourea were added to 5 mL of deionized water and ultrasonically dispersed to obtain mixed solutions B and C;

[0079] S3. 24 mL of mixed solution B and 5.4 mL of mixed solution C were successively added to 5.4 mL of mixed solution A, stirred evenly, and the pH of the solution was adjusted to 3 with hydrochloric acid, then placed in a polytetrafluoroethylene-lined autoclave containing 50 mL, sealed, and placed in a constant temperature oven at 185 ° C for 24 h. After the reaction, the mixture was cooled to room temperature and washed with ethanol to obtain a nano-molybdenum disulfide precursor solution;

[0080] S4. The nano-molybdenum disulfide precursor solution was placed in a culture dish and placed on a -50°C freeze dryer for 38 minutes to obtain a freeze-dried powder of nano-molybdenum disulfide;

[0081] S5. 27 g of graphite powder and 420 mL of concentrated sulfuric acid were added to a beaker and stirred in an ice bath for 24 h. 29 g of potassium permanganate and 840 mL of deionized water were then added while stirring. 470 mL of 540 mL of 30% hydrogen peroxide was added after stirring, and the mixture was allowed to stand for 24 h before centrifugation and washing. The mixture was then added to 10% hydrochloric acid and stirred for 14 min. The mixture was centrifuged, washed, and dialyzed for 48 h to obtain graphene oxide.

[0082] S6. Under a nitrogen atmosphere, 32 g of tungsten steel ball, 1.3 g of copper powder and 0.13 g of composite lubricant were added to the ball mill jar, and the ball mill was started for ball milling. After the ball milling operation was completed, the pretreated copper powder was filtered;

[0083] S7. 26 g of stearic acid and 6.5 g of freeze-dried nano-molybdenum disulfide powder were mixed to obtain a composite lubricant; 10.2 g of graphene oxide, 6.5 g of carbon fiber and 3.1 g of few-layer molybdenum disulfide were mixed to obtain a conductive filler; 3.7 g of ethylene-vinyl acetate copolymer, 3 g of acrylonitrile-styrene-acrylate terpolymer and 6.5 g of polybutylene terephthalate were mixed to obtain a resin matrix;

[0084] S8. To 65g of the resin matrix was added 6.2g of a conductive filler, 4.8g of a coupling agent, 4.2g of pretreated copper powder, 1.3g of an antioxidant, and 3.2g of a dispersant, and placed in a high-speed mixer at a temperature of 108°C and a speed of 1400r / min and continued to mix thoroughly for 23min to obtain a mixture 1;

[0085] S9. Mixture 1 is placed in a twin-screw extruder and the temperatures are set to: 168°C in zone 1, 178°C in zone 2, 188°C in zone 3, 198°C in zone 4, and 208°C in zone 5. The screw speed is 280 r / min. Mixture 1 is then extruded through a mold and cooled in a cooling water tank to obtain a connecting strip material.

[0086] Example 5: A continuous extrusion process for a highly conductive sensor connecting strip material, comprising the following steps:

[0087] S1. Add 1.5 g of molybdenum disulfide to 150 mL of 95% ethanol solution, stir well, and pour into a jet cavitation device with the following parameters: pressure of 170,000 kPa and circulating cooling water bath temperature of 13°C. The resulting suspension was then dried at 85°C to obtain a few-layer molybdenum disulfide.

[0088] S2. 5 g of sodium dodecylbenzenesulfonate was added to 30 mL of deionized water and ultrasonically dispersed until completely dissolved to obtain a mixed solution A; 0.5 g of sodium molybdate and 0.38 g of thiourea were added to 5 mL of deionized water and ultrasonically dispersed to obtain mixed solutions B and C;

[0089] S3. 25 mL of mixed solution B and 5.5 mL of mixed solution C were successively added to 5.5 mL of mixed solution A, stirred evenly, and the pH of the solution was adjusted to 3 with hydrochloric acid, then placed in a polytetrafluoroethylene-lined autoclave containing 50 mL, sealed, and placed in a constant temperature oven at 188 ° C for 24 h. After the reaction, the mixture was cooled to room temperature and washed with ethanol to obtain a nano-molybdenum disulfide precursor solution;

[0090] S4. The nano-molybdenum disulfide precursor solution was placed in a culture dish and placed on a -50°C freeze dryer for 40 minutes to obtain a freeze-dried powder of nano-molybdenum disulfide;

[0091] S5. 28 g of graphite powder and 430 mL of concentrated sulfuric acid were added to a beaker and stirred in an ice bath for 24 h. 30 g of potassium permanganate and 850 mL of deionized water were then added while stirring. After stirring, 500 mL of 30% hydrogen peroxide was added, and the mixture was allowed to stand for 24 h before centrifugation and washing. The mixture was then added to 10% hydrochloric acid and stirred for 15 min. The mixture was centrifuged, washed, and dialyzed for 48 h to obtain graphene oxide.

[0092] S6. Under a nitrogen atmosphere, 33 g of tungsten steel ball, 1.4 g of copper powder and 0.14 g of composite lubricant were added to the ball mill jar, and the ball mill was started for ball milling. After the ball milling operation was completed, the pretreated copper powder was filtered;

[0093] S7. 28 g of stearic acid and 7.2 g of freeze-dried nano-molybdenum disulfide powder were mixed to obtain a composite lubricant; 11.3 g of graphene oxide, 7 g of carbon fiber and 3.5 g of few-layer molybdenum disulfide were mixed to obtain a conductive filler; 4.2 g of ethylene-vinyl acetate copolymer, 3.5 g of acrylonitrile-styrene-acrylate terpolymer and 7 g of polybutylene terephthalate were mixed to obtain a resin matrix;

[0094] S8. To 66g of the resin matrix was added 6.5g of a conductive filler, 5g of a coupling agent, 4.5g of pretreated copper powder, 1.4g of an antioxidant and 3.5g of a dispersant, placed in a high-speed mixer at a temperature of 110°C and continued to mix thoroughly at a speed of 1500r / min for 25min to obtain a mixture 1;

[0095] S9. Mixture 1 is placed in a twin-screw extruder and the temperatures are set to: 170°C in zone 1, 180°C in zone 2, 190°C in zone 3, 200°C in zone 4, and 210°C in zone 5. The screw speed is 300 r / min. The mixture is then extruded through a mold and cooled in a cooling water tank to obtain a connecting strip material.

[0096] Comparative Example 1:

[0097] Compared with Example 1, this comparative example did not add a few layers of molybdenum disulfide during the preparation of the conductive filler. The remaining steps and parameters were the same and will not be repeated in this comparative example. Finally, a sensor connecting strip material was obtained.

[0098] Comparative Example 2:

[0099] Compared with Example 1, this comparative example did not add nano-molybdenum disulfide freeze-dried powder during the preparation of the composite lubricant. The remaining steps and parameters were the same and will not be repeated in this comparative example. Finally, a sensor connecting strip material was obtained.

[0100] Comparative Example 3:

[0101] Compared with Example 1, this comparative example only replaces "graphene oxide" with "graphene", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, a sensor connecting strip material is obtained.

[0102] Comparative Example 4:

[0103] Compared with Example 1, this comparative example only replaces "few-layer molybdenum disulfide" with "molybdenum disulfide", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, the sensor connecting strip material is obtained.

[0104] Comparative Example 5:

[0105] Compared with Example 1, this comparative example only replaces the "pretreated copper powder" with "copper powder", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, the sensor connecting strip material is obtained.

[0106] Performance testing:

[0107] Conductivity: The resistance test was performed on the connecting strip materials prepared in Examples 1 to 5 and Comparative Examples 1 to 5. The greater the resistance value, the lower the conductivity of the connecting strip material.

[0108] Tensile strength: Tensile tests were performed on the connecting strip materials prepared in Examples 1 to 5 and Comparative Examples 1 to 5, respectively.

[0109] Table 1

[0110] project Resistance value / Ω Tensile strength / MPa Example 1 22.5 38.2 Example 2 23.2 39.4 Example 3 25.1 40.2 Example 4 24.9 40.7 Example 5 23.5 38.5 Comparative Example 1 28.7 30.6 Comparative Example 2 27.4 32.5 Comparative Example 3 26.2 34.2 Comparative Example 4 26.5 34.8 Comparative Example 5 27.8 35.1

[0111] Data Analysis:

[0112] As can be seen from Table 1, the sensor connector material prepared by the present invention has improved tensile strength and higher conductivity. This may be due to the resin matrix prepared from ethylene-vinyl acetate copolymer, acrylonitrile-styrene-acrylate terpolymer, and polybutylene terephthalate. The combination of these three resin materials further improves the tensile strength and other mechanical properties of the matrix material. In the conductive filler, the two-dimensional structure of the few-layer molybdenum disulfide can form a dense network with the carbon fiber and graphene oxide, which not only enhances the overall conductivity of the connector material but also relieves stress concentration, thereby improving the material's mechanical properties. In the pretreated copper powder, the lubricant prepared by mixing stearic acid and freeze-dried nano-molybdenum disulfide powder not only improves ball milling efficiency, but also effectively inhibits copper powder oxidation and improves its dispersibility. Compared with existing technologies, this lubricant has broad application prospects.

[0113] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Within the scope of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0114] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. Highly conductive sensor connecting strip material, characterized in that: Including the following raw materials by weight: Resin matrix 60-66 parts; pretreated copper powder 3.3-4.5 parts; conductive filler 5.5-6.5 parts; antioxidant 1.1-1.4 parts; dispersant 2.8-3.5 parts; coupling agent 3.9-5 parts; The resin matrix is ​​obtained by mixing ethylene-vinyl acetate copolymer, acrylonitrile-styrene-acrylate terpolymer and polybutylene terephthalate in a mass ratio of 2-4.2:1.4-3.5:5-7; The pretreated copper powder is prepared by ball milling copper powder and a composite lubricant; The particle size of the pretreated copper powder is 1-6 μm; The composite lubricant is obtained by mixing stearic acid and nano-molybdenum disulfide freeze-dried powder in a mass ratio of 23-28:5.5-7.2; The conductive filler is obtained by mixing graphene oxide, carbon fiber and few-layer molybdenum disulfide in a mass ratio of 8-11.3:5-7:2.2-3.

5.

2. The highly conductive sensor connecting strip material according to claim 1, characterized in that: The preparation method of the few-layer molybdenum disulfide is as follows: Molybdenum disulfide was added to a 95% by mass ethanol solution, stirred evenly, and poured into a jet cavitation device. The parameters were set to obtain a suspension, which was then dried at 75-85°C to obtain a few-layer molybdenum disulfide.

3. The high-conductivity sensor connecting strip material according to claim 2, characterized in that: The molybdenum disulfide and ethanol solution are used in a ratio of 1-1.5 g: 100-150 mL; The pressure in the parameters is 150000-170000 KPa, and the temperature of the circulating cooling water bath is 8-13°C.

4. The highly conductive sensor connecting strip material according to claim 1, wherein: The preparation method of the nano molybdenum disulfide freeze-dried powder is as follows: Step A1. Sodium dodecylbenzenesulfonate was added to deionized water and ultrasonically dispersed until completely dissolved to obtain a mixed solution A; sodium molybdate and thiourea were added to deionized water and ultrasonically dispersed to obtain mixed solutions B and C; Step A2. Mixture B and mixture C were added to mixture A in sequence, stirred evenly, and the pH of the solution was adjusted to 2-3 with hydrochloric acid. The mixture was then placed in a 50 mL polytetrafluoroethylene-lined autoclave, sealed, and placed in a constant temperature oven for heat treatment. After the reaction, the mixture was cooled to room temperature and washed with ethanol to obtain a nano-molybdenum disulfide precursor solution. Step A3. Place the nano-molybdenum disulfide precursor solution in a culture dish and freeze it in a freeze dryer at -50°C for 30-40 minutes to obtain nano-molybdenum disulfide freeze-dried powder.

5. The highly conductive sensor connecting strip material according to claim 4, characterized in that: The ratio of sodium dodecylbenzenesulfonate and deionized water in step A1 is 3.5-5 g: 20-30 mL; The usage ratio of sodium molybdate and deionized water in step A2 is 0.42-0.5 g:5 mL.

6. The highly conductive sensor connecting strip material according to claim 4, characterized in that: The ratio of thiourea to deionized water in step A2 is 0.28-0.38 g:5 mL; The volume ratio of the mixed solution B, mixed solution C and mixed solution A is 20-25:5-5.5:5-5.5; the temperature during the heat treatment is 175-188° C. and the time is 22-24 hours.

7. The highly conductive sensor connecting strip material according to claim 1, wherein: The preparation method of the graphene oxide is as follows: Graphite powder and concentrated sulfuric acid were added to a beaker, mixed and stirred in an ice bath for 22-24 hours, and then potassium permanganate and deionized water were added while stirring. After stirring evenly, 30% by mass hydrogen peroxide was added, and the mixture was allowed to stand for 24 hours before centrifugation and washing. The mixture was then added to 10% by mass hydrochloric acid and stirred for 10-15 minutes. After centrifugation and washing, the mixture was dialyzed for 48 hours to obtain graphene oxide. The usage ratio of the graphite powder, concentrated sulfuric acid, potassium permanganate, deionized water, hydrogen peroxide and hydrochloric acid is 24-28 g: 380-430 mL: 25-30 g: 800-850 mL: 400-500 mL: 500-550 mL.

8. The highly conductive sensor connecting strip material according to claim 1, wherein: The preparation method of the pretreated copper powder is as follows: Under a nitrogen atmosphere, tungsten steel balls, copper powder and composite lubricant are sequentially added to a ball milling jar, and the ball mill is started to perform ball milling. After the ball milling operation is completed, the pretreated copper powder is filtered to obtain the pretreated copper powder; The mass ratio of the tungsten steel ball, copper powder and composite lubricant is 27-33:1-1.4:0.1-0.

14.

9. The highly conductive sensor connecting strip material according to claim 1, wherein: The antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; The dispersant is obtained by mixing isopropyl tristearate titanate and stearic acid in a mass ratio of 5-8:2.4-4.5; The coupling agent is γ-methacryloxypropyltrimethoxysilane.

10. The continuous extrusion process of the high-conductivity sensor connecting strip material according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step S1. Add a conductive filler, a coupling agent, a pretreated copper powder, an antioxidant, and a dispersant to the resin matrix, place it in a high-speed mixer, and continue to mix thoroughly at a temperature of 100-110°C and a speed of 1300-1500 r / min for 15-25 minutes to obtain a mixture 1; Step S2. Place the mixed material 1 in a twin-screw extruder and set the temperature to: 160-170°C in zone 1, 170-180°C in zone 2, 180-190°C in zone 3, 190-200°C in zone 4, and 200-210°C in zone 5, with a screw speed of 200-300 r / min. Then, the mixed material 1 is extruded through a mold and cooled in a cooling water tank to obtain a connecting strip material.