Device and method for preparing carbon nanotube master batch

Abstract

The invention discloses a carbon nanotube master batch preparation device, and relates to the field of carbon nanotube production, the carbon nanotube master batch preparation device comprises a shell and a screw rod arranged in the shell, the screw rod is internally provided with a U-shaped channel, and the screw rod is sleeved with a transition piece; a U-shaped channel is arranged in the transition piece, a partition plate is arranged in the transition piece, the partition plate divides the internal space of the transition piece into a first cavity and a second cavity, the two ends of the U-shaped channel are communicated with the first cavity and the second cavity respectively, an inlet is formed in the first cavity, and an outlet is formed in the second cavity. According to the preparation device of the carbon nanotube master batch provided by the invention, in the operation process of the screw, the cooling medium is injected into the U-shaped channel through the inlet and the first cavity and then is discharged from the second cavity and the outlet, so that a cycle is completed, the screw is cooled from the inside, and the service life of the screw is prolonged. Therefore, local overheating of the screw can be avoided as much as possible.

Description

Technical Field

[0001] This invention relates to the field of carbon nanotube production, and more specifically to an apparatus and method for preparing carbon nanotube masterbatch. Background Technology

[0002] As is generally known, carbon nanotube plastic masterbatch is prepared by dispersing carbon nanotubes in thermoplastic resin. The resulting carbon nanotube plastic particles are typically added to plastics to create conductive or electrostatic materials, serving as an intermediate material in composite and functional materials. In the field of conductive plastics, carbon nanotubes offer the following advantages over carbon black: 1. Less impact on impact strength; 2. Superior conductivity; 3. Better appearance of the finished product. The production process of its masterbatch requires the use of a twin-screw extruder to extrude the mixed dispersion.

[0003] For example, the Chinese patent document with authorization announcement number CN108084627B, announcement date of 2021-02-19, titled "HIPS-based conductive masterbatch based on carbon nanotube and graphene composite system and its preparation method", firstly, carbon nanotubes and graphene are uniformly dispersed in volatile inert solvents and treated with an ultrasonic treatment device for 1 hour. Then, the treated dispersion is stirred with the material in a high-speed mixer according to the ratio. After mixing with a compatibilizer in a certain ratio at room temperature, it is melt-extruded through a twin-screw extruder to prepare a conductive masterbatch.

[0004] The shortcoming of the existing technology is that when the screw extrudes the material, the traditional twin-screw extruder only controls the temperature through the outer wall of the barrel. However, during the operation of the screw, heat is generated due to the shearing process with the material, which can easily lead to local high temperature. Obviously, local high temperature will affect the mechanical properties of the masterbatch. Summary of the Invention

[0005] The purpose of this invention is to provide an apparatus and method for preparing carbon nanotube masterbatches to overcome the above-mentioned shortcomings in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A device for preparing carbon nanotube masterbatch includes a shell and a screw disposed inside the shell. The screw has a U-shaped channel inside and a transition piece sleeved on the screw. The transition member has a partition inside, which divides the internal space of the transition member into a first cavity and a second cavity. The two ends of the U-shaped channel are respectively connected to the first cavity and the second cavity. The first cavity has an inlet and the second cavity has an outlet. The cooling medium enters the U-shaped channel through the inlet and the first cavity, and then exits from the second cavity and the outlet.

[0007] In the aforementioned apparatus for preparing carbon nanotube masterbatch, there are two U-shaped channels.

[0008] The aforementioned apparatus for preparing carbon nanotube masterbatch includes a screw comprising a main shaft and a cylindrical section disposed on the main shaft, wherein a limiting structure is provided between the cylindrical section and the main shaft to prevent relative rotation between the two.

[0009] In the above-mentioned apparatus for preparing carbon nanotube masterbatch, a convex ring is provided on the cylindrical section, and an elastic element is provided between the convex ring and the shell.

[0010] The above-mentioned apparatus for preparing carbon nanotube masterbatch includes a limiting groove on the shell and a limiting block adapted to the limiting groove on the cylindrical section, wherein the limiting block is slidably connected to the limiting groove.

[0011] In the above-mentioned apparatus for preparing carbon nanotube masterbatch, an adjusting member is slidably disposed on the transition member, and both the inlet and the outlet are located on the movement stroke of the adjusting member; It also includes a power assembly for driving the movement of the adjusting member.

[0012] The above-mentioned apparatus for preparing carbon nanotube masterbatch includes an adjusting member comprising a first sealing ring slidably disposed in the first cavity and a second sealing ring slidably disposed in the second cavity, wherein a first connecting rod is provided between the first sealing ring and the second sealing ring.

[0013] The aforementioned apparatus for preparing carbon nanotube masterbatch includes a power component comprising a transmission ring, a second connecting rod disposed between the transmission ring and the first sealing ring, and the transmission ring being rotatably connected to the convex ring.

[0014] In the aforementioned apparatus for preparing carbon nanotube masterbatch, the screw is provided with an exhaust groove.

[0015] A method for preparing carbon nanotube masterbatch, based on the above-mentioned apparatus for preparing carbon nanotube masterbatch, includes the following steps: S1, preparing activated carbon nanotubes; S2, premixing; S3, granulation.

[0016] In the above technical solution, the present invention provides a carbon nanotube masterbatch preparation device in which, during the operation of the screw, a cooling medium is injected into the U-shaped channel through the inlet and the first cavity, and then discharged from the second cavity and the outlet, thus completing a cycle to cool the screw from the inside, thereby minimizing the possibility of local overheating of the screw. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a schematic diagram of the overall external structure provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the internal structure provided in an embodiment of the present invention; Figure 3 This is a cross-sectional structural diagram provided for an embodiment of the present invention; Figure 4 This is a partial structural schematic diagram provided for another embodiment of the present invention; Figure 5 This is a partial cross-sectional view of the screw structure provided in another embodiment of the present invention; Figure 6 This is a partial cross-sectional view of the screw structure provided in another embodiment of the present invention; Figure 7 This is a schematic diagram of the connection structure between the first sealing ring and the second sealing ring provided in another embodiment of the present invention; Figure 8 for Figure 5 Enlarged schematic diagram of the local structure at point a; Figure 9 for Figure 6 A magnified schematic diagram of the local structure at point A in the middle.

[0019] Explanation of reference numerals in the attached figures: 1. Shell; 2. Screw; 201. Feeding and mixing section; 202. Melting section; 203. Extrusion section; 3. U-shaped channel; 4. Transition component; 5. Partition plate; 6. First cavity; 7. Second cavity; 8. Inlet; 9. Outlet; 10. Main shaft; 11. Cylindrical section; 12. Convex ring; 13. Elastic component; 14. Rotating part; 15. Telescopic groove; 16. Limiting groove; 17. Limiting block; 18. First sealing ring; 19. Second sealing ring; 20. First connecting rod; 21. Transmission ring; 22. Second connecting rod; 23. Exhaust groove; 24. Connecting hole; 25. Conical area; 26. Main channel; 27. First channel; 28. Second channel; 29. ​​Baffle plate; 30. Transmission block; 31. Transmission rope; 32. Mounting groove. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0021] In the description of this invention, it should be understood that, Figure 6 The position of the inlet 8 relative to the outlet 9 is above, and vice versa. The terms "center", "longitudinal", "lateral", "length", "width", "degree", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0022] Reference Figure 1-3 This invention provides an apparatus for preparing carbon nanotube masterbatches, comprising a housing 1 and a screw 2 disposed inside the housing 1. A U-shaped channel 3 is disposed inside the screw 2, and a transition member 4 is sleeved on the screw 2. A partition 5 is disposed inside the transition member 4, dividing the internal space of the transition member 4 into a first cavity 6 and a second cavity 7. The two ends of the U-shaped channel 3 are respectively connected to the first cavity 6 and the second cavity 7. An inlet 8 is disposed on the first cavity 6, and an outlet 9 is disposed on the second cavity 7. Cooling medium enters the U-shaped channel 3 through the inlet 8 and the first cavity 6, and then exits from the second cavity 7 and the outlet 9.

[0023] Specifically, the shell 1 has a cylindrical structure and is equipped with heating structures such as electric heating wires. A feed inlet is located at the top. Two screws 2 are rotatably mounted inside the shell 1, arranged side-by-side and meshing with each other. Based on the shape and position of the threads on the screws 2, they are divided into a feeding and mixing section 201, a melting section 202, and an extrusion section 203. During material extrusion, a drive motor drives the two screws 2 to rotate synchronously and in opposite directions. Material is then added from the feed inlet at the top of the shell 1 to the middle position of the two feeding and mixing sections 201. Under the action of the rotating screws 2, the material moves along the axial direction of the shell 1. Under the extrusion action of the two screws 2, the material is sheared. The mixed material enters the melting section 202 for further processing, and then is extruded through the end of the extrusion section 203. This completes the entire extrusion process of the material. This is existing technology and will not be elaborated further. One of the core innovations of this invention is that a U-shaped channel 3 is provided inside the screw 2, and the U-shaped channel 3 is arranged along the length of the screw 2. Both ends of the U-shaped channel 3 are located on the outer circumferential surface of the screw 2. The transition piece 4 is a cylindrical structure sleeved on the outside of the screw 2 and located outside the shell 1. It can be fixed to the extruder body by bolts or other structures. The transition piece 4 is rotatably and sealed to the screw 2, and its internal space forms an annular cavity structure with the screw 2. The partition plate 5 is circular and is located in the middle of the transition piece 4, thus dividing the transition piece 4 into two annular cavities, namely the first cavity 6 and the second cavity 7. The inlet 8 communicates with the internal space of the first cavity 6, and the outlet 9 communicates with the internal space of the second cavity 7. The cooling medium is preferably cold air. The purpose of this arrangement is that during the operation of the screw 2, the cooling medium is sent into the first cavity 6 through the inlet 8 and fills the first cavity 6. During this period, the cooling medium enters the U-shaped channel 3 through one of the openings. Since the U-shaped channel 3 rotates synchronously with the screw 2, the position of the opening of the U-shaped channel 3 is uncertain. In this application, the first cavity 6 is annular, which can encompass the entire rotation stroke of the opening of the U-shaped channel 3. This ensures that during the rotation of the screw 2, a cooling medium will always enter the interior of the U-shaped channel 3 to achieve a continuous supply of cooling medium. Then, the cooling medium is discharged from the second cavity 7 and the outlet 9, thus completing a cycle to cool the screw 2 from the inside. This can minimize the possibility of local overheating of the screw 2. Furthermore, since the outlet 9 and the inlet 8 are located at the same end of the screw 2, the installation difficulty of the cooling structure can be reduced.

[0024] Preferably, there are two U-shaped channels 3 in a single screw 2. The two U-shaped channels 3 are arranged vertically inside the screw 2, that is, one U-shaped channel 3 is arranged horizontally and the other U-shaped channel 3 is arranged vertically, and the ends of the two U-shaped channels 3 are staggered. Cooling medium is injected into the two U-shaped channels 3 at the same time to increase the cooling area of ​​the screw 2, thereby improving the cooling effect of the screw 2.

[0025] Because the feeding mixing section 201 and melting section 202 of screw 2 shear the material and are accompanied by cavitation, the feeding mixing section 201 and melting section 202 of screw 2 are more prone to damage than the extrusion section 203. To specifically replace the feeding mixing section 201 and melting section 202 of screw 2, refer to... Figure 4 In another embodiment of the present invention, the screw 2 includes a main shaft 10 and a cylindrical section 11 disposed on the main shaft 10, and a limiting structure for preventing relative rotation between the cylindrical section 11 and the main shaft 10 is provided. Specifically, the cylindrical section 11 is sleeved on the outside of the main shaft 10. When installing the cylindrical section 11, first, the cylindrical section 11 is sleeved on the main shaft 10, and the position of the cylindrical section 11 can be fixed by bolts or other structures. Then, the transition piece 4 and other structures are installed on the main shaft 10. The feeding mixing section 201 and the melting section 202 are placed on the cylindrical section 11, and the extrusion section 203 is placed on the main shaft 10. The limiting structure can be a pin and pin hole structure set in the radial direction of the cylindrical section 11 and the main shaft 10, so that the main shaft 10 and the cylindrical section 11 can rotate synchronously. The purpose of this setting is that when the feeding mixing section 201 and the melting section 202 are damaged, the transition piece 4 is first removed from the main shaft 10, and then the cylindrical section 11 is removed from the main shaft 10. A new cylindrical section 11 is then installed on the main shaft 10, so as to achieve targeted replacement of the feeding mixing section 201 and the melting section 202 of the screw 2.

[0026] As an alternative to the bolt-fixed cylindrical section 11, preferably, a protruding ring 12 is provided on the cylindrical section 11, and an elastic element 13 is provided between the protruding ring 12 and the housing 1. Specifically, a rotating part 14 is rotatably provided on the housing 1, and a limiting structure is provided between the rotating part 14 and the housing 1 to prevent them from separating. A convex ring 12 is provided on one end of the cylindrical section 11 located outside the housing 1. The elastic element 13 is preferably a spring, one end of which is fixed to the convex ring 12 and the other end of which is fixed to the rotating part 14. A telescopic groove 15 is provided inside the main shaft 10. The end of the cylindrical section 11 away from the transition member 4 is inserted into the telescopic groove 15. An inclined surface is provided at the position where the cylindrical section 11 connects to the extrusion section 203 for material transition. The material at this position can move along the axial direction of the housing 1 under the pushing action of the material behind. The pin hole is a long strip structure provided along the length direction of the main shaft 10. The pin is fixed to the cylindrical section 11 so that when the cylindrical section 11 moves axially, the pin can slide a certain distance in the pin hole. The function of this arrangement is to... When the screw 2 rotates normally, the elastic force of the elastic element 13 keeps the cylindrical section 11 away from the transition element 4. When the rotation speed of the screw 2 increases, that is, the amount of material added from the feed inlet increases, which will increase the load on the screw 2 during the conveying process. When the reaction force of the material on the cylindrical section 11 is greater than the elastic force of the elastic element 13, the cylindrical section 11 moves towards the transition element 4 and stores force on the elastic element 13. The benefits of this are that the axial movement of the cylindrical section 11 can play a buffering role to protect the cylindrical section 11. On the other hand, when the axial movement distance between the two cylindrical sections 11 is inconsistent, the thread gap between the two cylindrical sections 11 can change. That is, when the thread gap becomes smaller, the threads on the two cylindrical sections 11 will have a squeezing effect on the material to improve the material dispersion effect.

[0027] Furthermore, the housing 1 is provided with a limiting groove 16, and the cylindrical section 11 is provided with a limiting block 17 adapted to the limiting groove 16. The limiting block 17 is slidably connected to the limiting groove 16. Specifically, the limiting groove 16 is provided on the inner circumferential surface of the rotating part 14 and has an elongated structure. The limiting block 17 is a protruding structure provided on the outer circumferential surface of the cylindrical section 11, and the length of the limiting groove 16 is 0.5cm-1cm longer than the length of the limiting block 17. The purpose of this arrangement is that when the screw 2 is normally conveying materials, the end of the limiting block 17 and the limiting groove 16 away from the transition piece 4 is in contact. When the cylindrical section 11 moves axially, it will drive the limiting block 17 to slide inside the limiting groove 16. When the limiting block 17 abuts against the side wall of the other end of the limiting groove 16, the maximum axial movement distance of the cylindrical section 11 is achieved. This distance is between 0.5cm and 1cm, thereby realizing the axial limitation of the cylindrical section 11.

[0028] Reference Figure 5 as well as Figure 8 In another embodiment of the present invention, an adjusting member is slidably disposed on the transition member 4, and the inlet 8 and the outlet 9 are both located on the movement stroke of the adjusting member; it also includes a power component for driving the adjusting member to move. The adjusting member includes a first sealing ring 18 slidably disposed in the first cavity 6 and a second sealing ring 19 slidably disposed in the second cavity 7, and a first connecting rod 20 is disposed between the first sealing ring 18 and the second sealing ring 19. Specifically, in order to facilitate the simultaneous adjustment of the positions of the two sealing rings, the first sealing ring 18 and the second sealing ring 19 are connected by the first connecting rod 20, and the first connecting rod 20 is slidably and sealingly connected to the partition 5. The power component can be an existing reciprocating drive component such as an electric push rod. The purpose of this arrangement is that when the screw 2 rotates normally, the power component places a part of the first sealing ring 18 at the position of the inlet 8 and a part of the second sealing ring 19 at the position of the outlet 9. At this time, the injection and discharge speeds of the cooling medium are not at their maximum values, that is, the cooling effect is not at its maximum value. When the speed sensor detects an increase in the rotation speed of screw 2, which means the material conveying speed is increasing, the local high temperature phenomenon of screw 2 will become more severe. At this time, the adjustment component is controlled by the power component to move horizontally. This causes the first sealing ring 18 to move away from the inlet 8, and the second sealing ring 19 to move away from the outlet 9 at the same time, thereby fully opening the inlet 8 and the outlet 9. This allows the injection and discharge speeds of the cooling medium to be at their maximum values, thereby improving the cooling effect of screw 2. In this way, the cooling effect of the U-shaped channel 3 on screw 2 is actively adjusted based on the rotation speed of screw 2.

[0029] As an alternative to the aforementioned electric push rod control adjustment component for horizontal movement, preferably, the power assembly includes a transmission ring 21, with a second connecting rod 22 disposed between the transmission ring 21 and the first sealing ring 18, and the transmission ring 21 rotatably connected to the convex ring 12. Specifically, a second connecting rod 22 is disposed on the first sealing ring 18, penetrating the side wall of the transition member 4, and the transmission ring 21 is fixed to the end of the second connecting rod 22 and coaxially arranged with the adjustment component, cylindrical section 11, and other structures. A limiting mechanism, such as a limit ring, is provided between the transmission ring 21 and the convex ring 12 to prevent axial movement between them. This arrangement ensures that when the rotational speed of the screw 2 increases, the reaction force on the cylindrical section 11 increases, causing the cylindrical section 11 to move towards the transition member 4, and causing the convex ring 12 and the transmission ring 21 to move synchronously. Under the transmission action of rod 22 and the first connecting rod 20, the first sealing ring 18 will passively move away from the inlet 8, and the second sealing ring 19 will passively move away from the outlet 9, so that the injection and discharge speed of the cooling medium is at its maximum value. In this way, the cooling effect of the U-shaped channel 3 on the screw 2 is passively adjusted based on the rotation speed of the screw 2. Conversely, when the rotation speed of the screw 2 returns to normal, and when the reaction force of the material on the screw 2 is less than the elastic force of the elastic element 13, the elastic force of the elastic element 13 is released, so as to drive the adjusting element to move in the opposite direction for reset.

[0030] It should be noted that carbon nanotubes easily adsorb air during the mixing process, and gas is generated when the polymer melts. Residual gas can cause defects such as bubbles and shrinkage cavities in the masterbatch. To solve these problems, refer to... Figure 6-7 as well as Figure 9 In another embodiment of the present invention, the screw 2 is provided with an exhaust groove 23. Specifically, the exhaust groove 23 is opened on the outer peripheral surface of the main shaft 10, and there should be no less than one. The cylindrical section 11 is also provided with a connecting hole 24 adapted to the exhaust groove 23. The length of the opening of the exhaust groove 23 is greater than the horizontal movement distance of the cylindrical section 11, and the connecting hole 24 is located away from the feed inlet. A filter screen or other blocking structure can be provided at the position of the connecting hole 24 to prevent material from entering. The purpose of this arrangement is that during the extrusion process of the extruder, the gas generated during the melting process will be discharged from the position of the exhaust groove 23, thereby minimizing the occurrence of defects such as bubbles and shrinkage cavities in the masterbatch.

[0031] Furthermore, the U-shaped channel 3 has a tapered structure at one end near the outlet 9, and a tapered region 25 is provided on the main shaft 10. The exhaust groove 23 includes a main channel 26 and a first channel 27 and a second channel 28 connected to the main channel 26. The opening end of the first channel 27 is located on the outer circumferential surface of the main shaft 10. The second channel 28 is connected to the tapered region 25. A baffle 29 is rotatably provided inside the exhaust groove 23 by a torsion spring (not shown). A transmission block 30 is slidably provided on the main shaft 10. A transmission rope 31 is provided between the transmission block 30 and the baffle 29. The transmission block 30 is located on the movement stroke of the transmission ring 21. Specifically, the opening of the tapered structure, i.e., the U-shaped channel 3, is smaller than its central size. The tapered region 25 is fitted outside the opening of the U-shaped channel 3. The first channel 27 is arranged radially along the main shaft 10, and the second channel 28 is arranged axially along the main shaft 10. The baffle 29 is rotatably positioned at the connection between the first channel 27 and the second channel 28 via a torsion spring. It has a first position that blocks the first channel 27 and a second position that blocks the second channel 28. The transmission rope 31 is preferably made of a metal material with low ductility. A through hole is opened inside the main shaft 10 for transmission. Rope 31 connects baffle 29 and transmission block 30 through a through hole. A mounting groove 32 is provided on the outer surface of the main shaft 10. The transmission block 30 is slidably disposed within the mounting groove 32, and the two cannot be disengaged. This arrangement ensures that when the screw 2 rotates normally, to prevent heat loss from the inside of the housing 1, baffle 29 is in a second position under the action of the torsion spring, blocking the second channel 28. Gas in the main channel 26 will slowly exit through the first channel 27. As the rotational speed of the screw 2 increases, the amount of gas generated inside the housing 1 also increases, causing… The cylindrical section 11 moves axially under force, thereby driving the transmission ring 21 to move synchronously. During this process, the transmission ring 21 comes into contact with the transmission block 30, causing the transmission block 30 to slide horizontally inside the mounting groove 32. The transmission rope 31 pulls the baffle 29 to rotate, switching the baffle 29 from the second position to the first position and storing force on the torsion spring. At this time, the first channel 27 is blocked, and the second channel 28 is opened. The gas in the main channel 26 enters the second channel 28. Since the second channel 28 is connected to the conical region 25, and since the cooling medium passes quickly through the conical region 25, from... This creates a pressure difference between the conical region 25 and the second channel 28. As a result, the flowing cooling medium has a suction effect on the gas inside the second channel 28, which can accelerate the gas discharge and also accelerate the heat discharge inside the housing 1. When the speed of the screw 2 returns to normal, the transmission ring 21 moves in the opposite direction and moves away from the transmission block 30. At this time, the spring force of the torsion spring is released to drive the baffle 29 to rotate in the opposite direction, thereby passively switching the baffle 29 from the first position to the second position. During this process, the transmission block 30 is pulled in the opposite direction by the transmission rope 31 to reset.

[0032] Another embodiment of the present invention provides a method for preparing carbon nanotube masterbatch, which is based on the above-mentioned apparatus for preparing carbon nanotube masterbatch, and includes the following steps: S1, preparing activated carbon nanotubes by dissolving a dispersant (one or a mixture of two or more of the following: sodium dodecylbenzenesulfonate, polyvinylpyrrolidone, polyvinyl alcohol, xanthan gum, sodium dodecyl sulfate, polyethylene glycol octylphenyl ether, sodium carboxymethyl cellulose, dihexadecanophosphate, gum arabic, hexadecyltrimethylammonium bromide, alkylphenol ethylene oxide condensate emulsifier, hexadecyltrimethylammonium bromide, and polyvinylidene fluoride) in a solvent (water, N,N-dimethylformamide, N-methylpyrrolidone, n-butanol, chloroform, and anhydrous ethanol). A dispersant solution is obtained by mixing PE polymer matrix material, activated carbon nanotubes, dispersant, and coupling agent (one or a mixture of two of titanate coupling agents and silane coupling agents) in a mixture of acetone, petroleum ether, ethyl acetate, and butyl acetate. The dispersant solution is then sprayed into carbon nanotubes under high pressure and mixed at high speed to obtain activated carbon nanotubes. S2, Premixing: PE polymer matrix material, activated carbon nanotubes, dispersant, and coupling agent (one or a mixture of two of titanate coupling agents and silane coupling agents) are mixed. S3, Granulation: The material is extruded from a twin-screw extruder and granulated, wherein the screw speed of the twin-screw extruder is 100~1000 r / min, the extrusion temperature is 300-150℃, and the die temperature is 150~250℃.

[0033] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An apparatus for preparing carbon nanotube masterbatch, comprising a shell and a screw disposed inside the shell, characterized in that, The screw has a U-shaped channel inside and a transition piece is sleeved on the screw; The transition piece is provided with a partition, which divides the internal space of the transition piece into a first cavity and a second cavity. The two ends of the U-shaped channel are respectively connected to the first cavity and the second cavity. The first cavity is provided with an inlet, and the second cavity is provided with an outlet. The cooling medium enters the U-shaped channel through the inlet and the first cavity, and then exits from the second cavity and the outlet. The screw includes a main shaft and a cylindrical section disposed on the main shaft, and a limiting structure is provided between the cylindrical section and the main shaft to prevent relative rotation between the two. A protruding ring is provided on the cylindrical section, and an elastic element is provided between the protruding ring and the shell; A rotating part is rotatably provided on the housing, and a limiting structure is provided between the rotating part and the housing to prevent them from separating from each other. A convex ring is provided on one end of the cylindrical section located outside the housing. One end of the elastic element is fixed to the convex ring, and the other end is fixed to the rotating part. A telescopic groove is provided inside the main shaft, and the end of the cylindrical section away from the transition piece is inserted into the telescopic groove. An adjusting member is slidably disposed on the transition member, and both the inlet and the outlet are located on the movement stroke of the adjusting member; It also includes a power assembly for driving the movement of the adjusting member; The adjusting component includes a first sealing ring slidably disposed in the first cavity and a second sealing ring slidably disposed in the second cavity, and a first connecting rod is provided between the first sealing ring and the second sealing ring; The power assembly includes a transmission ring, and a second connecting rod is provided between the transmission ring and the first sealing ring. The transmission ring is rotatably connected to the convex ring.

2. The apparatus for preparing carbon nanotube masterbatch according to claim 1, characterized in that, There are two U-shaped channels.

3. The apparatus for preparing carbon nanotube masterbatch according to claim 1, characterized in that, The housing is provided with a limiting groove, and the cylindrical section is provided with a limiting block adapted to the limiting groove. The limiting block is slidably connected to the limiting groove.

4. The apparatus for preparing carbon nanotube masterbatch according to claim 1, characterized in that, The screw is provided with an exhaust groove.

5. A method for preparing carbon nanotube masterbatch, based on the apparatus for preparing carbon nanotube masterbatch according to any one of claims 1-4, characterized in that, Includes the following steps: S1, Preparation of activated carbon nanotubes; S2, Premixing; S3, Granulation.

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