Twin-screw extruder for promoting blending of antibacterial and antifogging master batch

Abstract

The utility model discloses a double-screw extruder capable of promoting blending of antibacterial and antifogging master batches. The double-screw extruder comprises temperature control cylinders which are communicated with each other, the top of the temperature control machine barrel is communicated with a plurality of groups of blanking bins through a pipeline, and a metering conveying device is arranged on the pipeline; a heating device is arranged in the temperature control machine barrel; and the top of the temperature control machine barrel is communicated with a vacuumizing chamber. According to the utility model, a plurality of groups of temperature control machine barrels are matched with heating rods or heating plates to form a multi-section gradient heating conveying channel, and in the front section, resin is rapidly melted at high temperature and then is subjected to gradient cooling to be directionally sheared, stretched and blended with an antifogging agent and an antibacterial agent, so that the stability difference of materials can be effectively coordinated; according to the melting sequence, the blanking bin is matched with the liquid metering scale or the electric conveyor to sequentially and synchronously feed materials, so that the mixing consistency and the product performance are effectively improved; and the vacuumizing chamber discharges dissipated volatile matters and water vapor for multiple times, so that the problems of rough product surface and poor dispersion uniformity caused by residual bubbles are solved.

Description

Technical Field

[0001] This utility model relates to the field of screw extruder technology, specifically to a twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch. Background Technology

[0002] Antibacterial and antifogging masterbatch is a high-molecular-weight material additive with special functions. It is usually made from a variety of components, including antibacterial agents, antifogging agents, and carrier resins, through a special process. The antibacterial agent effectively inhibits the growth and reproduction of bacteria, molds, and other microorganisms, preventing problems such as odor, discoloration, and performance degradation on the surface of plastic films caused by microbial growth. The antifogging agent reduces the surface tension of the material, allowing water vapor to form a uniform water film on the surface instead of condensing into water droplets, reducing light refraction and reflection, and maintaining the clarity and transparency of the plastic film surface. Antibacterial and antifogging masterbatch has good dispersibility and stability in plastic films, and can be evenly distributed in the base materials of plastic products, giving the products excellent antibacterial and antifogging properties. It is widely used in food packaging, medical devices, automotive interiors, and bathroom products.

[0003] When preparing masterbatch, the existing screw extruder adopts a single heating zone synchronous feeding and continuous heating scheme. Due to the large difference in the melting points of materials, problems such as premature decomposition of low-melting-point materials, insufficient melting of high-temperature materials, degradation of additives, and residues of volatiles are prone to occur. In addition, since the feeding relies on manual feeding or single-point metering, there are synchronous injection errors, which lead to fluctuations in the blending ratio, resulting in rough surface of the extruded strip, poor dispersion uniformity, and low performance stability. Utility Model Content

[0004] The purpose of this invention is to provide a twin-screw extruder that promotes the blending of antibacterial and anti-fogging masterbatches in order to solve the above problems.

[0005] To achieve the above objectives, this utility model specifically adopts the following technical solution, including:

[0006] The interconnected temperature-controlled barrels form a multi-segment gradient heating and conveying channel;

[0007] The top of the temperature-controlled barrel is connected to multiple sets of feeding hoppers via pipelines. A metering and conveying device is installed on the pipelines connecting the temperature-controlled barrel to one or more sets of feeding hoppers. The metering and conveying device is used to synchronously convey raw materials.

[0008] One or more sets of the temperature-controlled barrels are equipped with heating devices inside, and the heating devices are used for gradient heating of the mixed materials;

[0009] The top of the temperature-controlled barrel is connected to multiple vacuum chambers via pipelines, and the vacuum chambers are used to extract gas.

[0010] As a further description of the above technical solution, the feeding bin includes a first feeding bin, a second feeding bin, and a third feeding bin arranged sequentially at the top of the temperature-controlled barrel, and the feeding bin is used to simultaneously feed masterbatch raw materials.

[0011] As a further description of the above technical solution, the metering and conveying device includes a liquid metering scale and an electric conveyor. The liquid metering scale is installed on the pipeline connecting the temperature-controlled cylinder and the second discharge bin, and the electric conveyor is installed on the pipeline connecting the temperature-controlled cylinder and the third discharge bin.

[0012] As a further description of the above technical solution, the heating device includes heating rods and heating plates. One or more sets of temperature-controlled barrels are equidistantly arranged with multiple sets of heating rods inside, and one or more sets of temperature-controlled barrels are provided with heating plates circumferentially arranged on the inner wall of the inner wall.

[0013] As a further description of the above technical solution, the vacuum chamber includes a primary vacuum chamber and a secondary vacuum chamber, and the vacuum chamber is used to extract volatiles and water vapor from inside the temperature control cylinder.

[0014] As a further description of the above technical solution, the primary vacuum chamber is located at the top of the temperature-controlled barrel on the side of the third feeding bin close to the second feeding bin, and the secondary vacuum chamber is located at the top of the temperature-controlled barrel on the side of the third feeding bin away from the second feeding bin.

[0015] As a further description of the above technical solution, the temperature-controlled barrel is provided with multiple sets of mixing devices. The mixing device includes a combined threaded block, a mixing and kneading threaded block, a kneading block, a conveying block, and a shearing block arranged sequentially on the twin screws. The combined threaded block and the mixing and kneading threaded block are arranged inside the temperature-controlled barrel that communicates with the second discharge bin. The kneading block, the conveying block, and the shearing block are arranged inside the temperature-controlled barrel that communicates with the third discharge bin.

[0016] As a further description of the above technical solution, a driving device is provided at one end of the temperature control cylinder. The driving device includes a gearbox, which is detachably connected to the temperature control cylinder through a spline connecting sleeve. The gearbox is rotatably connected to the motor unit through a gearbox and a coupling protector.

[0017] As a further description of the above technical solution, a discharge device is provided at the other end of the temperature-controlled barrel. The discharge device includes a screen changer, which is detachably connected to the temperature-controlled barrel. A heating coil is provided on the outside of the screen changer, and an extrusion die is provided outside the heating coil.

[0018] As a further description of the above technical solution, the temperature-controlled barrel and the drive device are detachably mounted on the frame.

[0019] The beneficial effects of this utility model are as follows:

[0020] 1. In this utility model, multiple sets of temperature-controlled barrels are combined with heating rods or heating plates to form a multi-stage gradient heating and conveying channel. After the resin is rapidly melted at high temperature in the front section, it is gradually cooled down and mixed with anti-fogging agent and antibacterial agent through directional shearing and stretching, which can effectively coordinate the differences in material stability.

[0021] 2. In this utility model, multiple sets of feeding hoppers are used in conjunction with liquid metering scales or electric conveyors to feed materials synchronously in sequence according to the melting order. The combined threaded block, mixing and kneading threaded block, kneading block, conveying block and shearing block arranged in sequence on the twin screw can forcibly disperse nanoparticles, which can effectively improve the mixing consistency and product performance.

[0022] 3. This utility model uses multiple vacuum chambers to repeatedly expel volatile substances and water vapor, solving the problem of rough product surface and poor dispersion uniformity caused by residual air bubbles.

[0023] To more clearly illustrate the structural features and functions of this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatches, according to this utility model. Figure 1 ;

[0025] Figure 2 This is a schematic diagram of the structure of a twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatches, according to this utility model. Figure 2 .

[0026] Figure label:

[0027] 1. Temperature-controlled barrel; 2. Feeding hopper; 21. First feeding hopper; 22. Second feeding hopper; 23. Third feeding hopper; 3. Metering and conveying device; 31. Liquid metering scale; 32. Electric conveyor; 4. Heating device; 41. Heating rod; 42. Heating plate; 5. Vacuum chamber; 51. Primary vacuum chamber; 52. Secondary vacuum chamber; 6. Mixing device; 61. Combined threaded block; 62. Mixing and kneading threaded block; 63. Kneading block; 64. Conveying block; 65. Shearing block; 7. Drive device; 71. Gearbox; 72. Spline connecting sleeve; 73. Gearbox; 74. Coupling protector; 75. Motor unit; 8. Discharge device; 81. Screen changer; 82. Heating coil; 83. Extrusion die; 9. Frame. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0029] like Figures 1-2 As shown, in one embodiment, a twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch includes: interconnected temperature-controlled barrels 1, with multiple sets of temperature-controlled barrels 1 forming a continuous and closed multi-segment gradient heating and conveying channel.

[0030] Understandably, multiple temperature-controlled barrels 1, together with heating rods 41 or heating plates 42, form multi-segment gradient heating and conveying channels, which can independently and precisely control the temperature to meet the process requirements at different stages: in the front section of the channel, the high-temperature environment can quickly heat the resin to a molten state, making it soften rapidly; in the middle and rear sections of the channel, in the gradually cooling environment, anti-fogging agents and antibacterial agents are precisely and synchronously added, and through the mixing device 6 inside the equipment, directional shear stretching blending is achieved, which can effectively coordinate the differences in material stability and ensure that the final product achieves a high degree of consistency and stability in performance.

[0031] Furthermore, the top of the temperature control cylinder 1 is connected to multiple sets of feeding bins 2 via pipelines, and the feeding bins 2 are arranged sequentially along the axial direction of the temperature control cylinder 1, including the first feeding bin 21, the second feeding bin 22 and the third feeding bin 23. Each bin adopts a conical bottom design, which can realize the precise and synchronous dispensing of resins (such as polypropylene resin, polyethylene resin, etc.), anti-fogging agents (such as glyceryl monostearate, sorbitan monooleate, etc.) and antibacterial agents (such as silver-based antibacterial agents, quaternary ammonium salt antibacterial agents, etc.).

[0032] It should be noted that a metering and conveying device 3 is installed on the pipeline connecting the temperature-controlled barrel 1 to one or more sets of feeding hoppers 2 for synchronously conveying raw materials. Specifically, the metering and conveying device 3 includes a liquid metering scale 31 and an electric conveyor 32. The liquid metering scale 31 is installed on the pipeline connecting the temperature-controlled barrel 1 to the second feeding hopper 2, while the electric conveyor 32 is installed on the pipeline connecting the temperature-controlled barrel 1 to the third feeding hopper 2.

[0033] It is understandable that the temperature-controlled feed cylinder is divided into sections sequentially from the feed inlet to the discharge outlet (e.g., ...). Figure 1 As shown, including zones 1-16, during processing, PP resin is fed sequentially and synchronously from multiple sets of feeding hoppers 2 in conjunction with liquid metering scales 31 or electric conveyors 32 according to the melting sequence: First, PP resin is injected from the first feeding hopper 2 into the temperature-controlled barrel 1 in zone 1 through a double-screw feeder (initial filling rate 65%-70%); then, liquid anti-fogging agent is injected from the second feeding hopper 2 into the temperature-controlled barrel 1 in zone 4 through the liquid metering scale 31 (accuracy ±0.3%) under side pressure, utilizing the negative pressure suction effect to instantly mix with the molten PP and avoid premature evaporation; finally, antibacterial agent is injected from the third feeding hopper 2 into the temperature-controlled barrel 1 in zone 7 through the electric conveyor 32 (integrated with a Coriolis flow meter and a ferroelectric pump, dynamically adjusting the amount of antibacterial agent injected, error <0.5%), i.e., the injection in the section with the lowest melt viscosity, thereby improving dispersion efficiency.

[0034] Please continue reading. Figures 1-2 In this embodiment, one or more temperature-controlled barrels 1 are equipped with heating devices 4 for gradient heating of the mixed materials.

[0035] Specifically, the heating device 4 includes heating rods 41 and heating plates 42. One or more sets of heating rods 41 are equidistantly arranged inside the temperature-controlled barrel 1 to form a longitudinal three-dimensional heating network. One or more sets of heating plates 42 are arranged around the inner wall of the temperature-controlled barrel 1 and are attached to the inner wall of the temperature-controlled barrel 1 by means of laser welding or other methods to form an annular heating cavity, which not only ensures efficient heat conduction but also effectively prevents the risk of leakage and ensures the safe operation of the equipment.

[0036] It should be explained in detail that the first half of the temperature control barrel 1 adopts an eight-segment independent temperature control scheme, with the temperature gradient of each zone set at 120 / 150 / 180 / 200 / 210 / 195 / 185 / 170℃, precisely matching the processing characteristics of different materials: when flowing through zones 1-3, the temperature is rapidly increased by heating rod 41 (power density 4W / cm2) to match the resin melting rate with the twin-screw conveying capacity. The heating plate 42 in zones 4-8 maintains the temperature precisely (maintained at ±1℃ by PID control module). Through precise temperature maintenance at 195℃, the risk of decomposition of anti-fogging agent in high-temperature environments above 200℃ is effectively avoided, and the contradiction between resin melting and the thermal stability of anti-fogging agent is coordinated.

[0037] Furthermore, the top of the temperature control cylinder 1 is connected to multiple sets of vacuum chambers 5 via pipelines, which are used to efficiently extract volatiles and water vapor generated during material processing.

[0038] It should be explained in detail that the vacuum chamber 5 includes a primary vacuum chamber 51 and a secondary vacuum chamber 52. Specifically, the primary vacuum chamber 51 is located at the top of the temperature-controlled barrel 1 on the side of the third feeding hopper 2 closest to the second feeding hopper 2, corresponding to the mixing stage after the anti-fogging agent is added (maintaining a stable vacuum of -0.08 MPa), and can effectively capture and remove the generated large molecular volatiles (such as incompletely polymerized monomers, oligomers, etc.); correspondingly, the secondary vacuum chamber 52 is located at the top of the temperature-controlled barrel 1 on the side of the third feeding hopper 2 furthest from the second feeding hopper 2, corresponding to the mixing stage after the antibacterial agent is added (maintaining a stable vacuum of -0.095 MPa), and can effectively extract and remove residual small molecular impurities (such as trace decomposition products, water vapor, and other low-boiling-point compounds that may be generated by the anti-fogging agent at high temperatures).

[0039] Understandably, multiple vacuum chambers repeatedly expel volatiles and moisture, eliminating the risk of bubbles caused by residual volatiles and effectively preventing roughness defects on the product surface caused by bubble rupture. At the same time, it ensures that additives such as anti-fogging agents and antibacterial agents are uniformly dispersed at the nanoscale in the resin matrix, significantly improving the appearance quality and performance stability of the final product.

[0040] Please continue reading. Figures 1-2 In this embodiment, the temperature-controlled barrel 1 is equipped with multiple mixing devices 6. Each mixing device 6 includes a combined threaded block 61, a mixing and kneading threaded block 62, a kneading block 63, a conveying block 64, and a shearing block 65, which are sequentially arranged on a twin screw. Specifically, the combined threaded block 61 and the mixing and kneading threaded block 62 are located inside the temperature-controlled barrel 1, which communicates with the second discharge bin 2, while the kneading block 63, the conveying block 64, and the shearing block 65 are located inside the temperature-controlled barrel 1, which communicates with the third discharge bin 2.

[0041] It should be explained in detail that the combined threaded block 61 has alternating forward and reverse threads (lead ratio 1:2) to form a high shear zone (shear rate 1500g). The extreme flow field environment can effectively break up the micron-sized agglomerates formed by the antibacterial agent, so that the nanoparticles are uniformly dispersed at their original particle size. The mixing and kneading threaded block 62 can generate a tensile flow field (60° staggered kneading disc), and a convergent-expanding flow channel structure is formed between adjacent discs. Under the action of interfacial tension, the antifogging agent is uniformly coated on the PP resin matrix as microdroplets (particle size <10μm), while the antibacterial agent nanoparticles are oriented.

[0042] Understandably, the combined threaded block 61, mixing and kneading threaded block 62, kneading block 63, conveying block 64 and shearing block 65 arranged sequentially on the twin screw can forcibly disperse nanoparticles, allowing the material to undergo a complete processing process of "conveying-dispersion-mixing-homogenization-stabilization", effectively improving mixing consistency and product performance.

[0043] Please continue reading. Figures 1-2 In this embodiment, a drive device 7 is provided at one end of the temperature control cylinder 1. The drive device 7 includes a gearbox 71. The gearbox 71 is detachably connected to the temperature control cylinder 1 through a spline connecting sleeve 72. The gearbox 71 is rotatably connected to the motor assembly 75 through a gearbox 73 and a coupling protector 74.

[0044] For example, the motor unit 75 uses an AC motor (power 250kW) to independently control the rotation of the twin screws (speed 60-600r / min), and adjusts the torque in real time through a frequency converter to match changes in resin melt viscosity, thus avoiding speed fluctuations caused by single motor overload; the coupling protector 74 integrates a torque limiter (threshold 800N·m) and a load monitoring module, which can quickly (within 0.1s) cut off power when the screws are blocked or the load changes suddenly, preventing overload of the gearbox 71 and the twin screws. Damage; the high-torque gearbox 71 adopts a three-stage reduction torque distribution (using a combination of planetary gears and helical gears, with a speed ratio of 24:1, increasing the output torque to 4500 N·m), and distributes it to the twin screws to achieve differential rotation (speed difference ratio 1:1.2), enhancing the shearing and dispersion effect; the spline connecting sleeve 72 adopts a thermal expansion compensation scheme, namely an involute spline (module 3, pressure angle 30°, allowing screw axial float of +5mm), to compensate for the thermal expansion difference between the temperature control barrel 1 and the twin screws, and avoid the twin screws from jamming.

[0045] Furthermore, a discharge device 8 is provided at the other end of the temperature-controlled barrel 1. The discharge device 8 includes a screen changer 81, which is detachably connected to the temperature-controlled barrel 1. A heating coil 82 is provided on the outside of the screen changer 81, and an extrusion die 83 is provided on the outside of the heating coil 82.

[0046] For example, a filter screen (400 mesh) is installed in the screen changer 81 for filtration. The material passing through the filter screen is heated by the high-frequency heating coil 82 and then extruded into long strip products from the holes (16 5m holes) of the extrusion die 83 for granulation.

[0047] Working principle: The temperature-controlled barrel 1 and the drive unit 7 are detachably mounted on the frame 9. The motor unit 75 at one end of the frame 9 is connected to the coupling protector 74 by a keyway. The coupling protector 74 is connected to the high-torque gearbox 71 by a spline. After the motor speed is reduced from 1450 r / min to 60-600 r / min, the output spline shaft of the gearbox 71 is connected to the two main screws of the extruder through the spline connecting sleeve 72 to drive the main screws to rotate. Then, the resin, anti-fogging agent and antibacterial agent are accurately metered and delivered to the temperature-controlled barrel of the extruder by the feeding bins 2 designed in different positions. During this process, the multi-stage temperature-controlled barrel of the extruder is heated and kept warm by the heating rod 41 or heating plate 42 according to the temperature gradient. The resin, anti-fogging agent and antibacterial agent entering the hopper are then heated and kept warm. The material undergoes rapid melting and shearing mixing. During the melting process, the twin screws rotate at 350 r / min to push the material. The combined threaded block 61, mixing and kneading threaded block 62, kneading block 63, conveying block 64, and shearing block 65 on the twin screws mix, knead, and shear the material, completing the twin screw melt blending extrusion process. This allows the antibacterial agent and anti-fogging agent to be fully mixed and dispersed with the resin, effectively reducing the dispersion particle size of the antibacterial agent and the decomposition rate of the anti-fogging agent. The moisture generated during the material melting and the volatiles generated during mixing are extracted and discharged through multiple vacuum chambers 5. Impurities or large particles in the material are filtered through a 400-mesh filter installed in the screen changer 81. The material that passes through the filter is then heated by a high-frequency heating coil 82 and extruded into long strips through 16 5 μm holes in the extrusion die 83 for granulation.

[0048] The table below shows the performance indicators of the granules produced by the twin-screw extruder that promotes the blending of antibacterial and anti-fogging masterbatches according to this application.

[0049] Table 1 - Overview of Performance Indicators of Granulated Products

[0050] index Traditional equipment Equipment in this application Antibacterial agent dispersion particle size 2-5um 0.3-1um Thermal decomposition rate of antifogging agent ≥12％ ≤5％ Masterbatch transparency ≤78％ ≥82％ Volatile residue ≤0.8％ ≤0.2％

[0051] Through the above technical solutions, this application achieves nanoscale dispersion of antibacterial agents (particle size less than 1 μm), low-loss blending of antifogging agents (thermal decomposition rate < 5%), significantly improves the transparency of masterbatch (transparency ≥ 82%) and reduces the residual amount of volatiles (residual amount ≤ 0.2%).

[0052] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatches, characterized in that, include: The interconnected temperature-controlled barrels form a multi-segment gradient heating and conveying channel; The top of the temperature-controlled barrel is connected to multiple sets of feeding hoppers via pipelines. A metering and conveying device is installed on the pipelines connecting the temperature-controlled barrel to one or more sets of feeding hoppers. The metering and conveying device is used to synchronously convey raw materials. One or more sets of the temperature-controlled barrels are equipped with heating devices inside, and the heating devices are used for gradient heating of the mixed materials; The top of the temperature-controlled barrel is connected to multiple vacuum chambers via pipelines, and the vacuum chambers are used to extract gas.

2. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 1, characterized in that, The feeding hopper includes a first feeding hopper, a second feeding hopper, and a third feeding hopper, which are sequentially arranged on the top of the temperature control cylinder. The feeding hopper is used to simultaneously feed the masterbatch raw materials.

3. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 2, characterized in that, The metering and conveying device includes a liquid metering scale and an electric conveyor. The liquid metering scale is installed on the pipeline connecting the temperature-controlled cylinder and the second discharge bin, and the electric conveyor is installed on the pipeline connecting the temperature-controlled cylinder and the third discharge bin.

4. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 1, characterized in that, The heating device includes heating rods and heating plates. One or more sets of heating rods are equidistantly arranged inside the temperature-controlled barrel, and one or more sets of heating plates are arranged around the inner wall of the temperature-controlled barrel.

5. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 1, characterized in that, The vacuum chamber includes a primary vacuum chamber and a secondary vacuum chamber, which is used to extract volatiles and water vapor from inside the temperature control cylinder.

6. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 5, characterized in that, The primary vacuum chamber is located at the top of the temperature-controlled barrel on the side of the third feeding hopper closest to the second feeding hopper, and the secondary vacuum chamber is located at the top of the temperature-controlled barrel on the side of the third feeding hopper furthest from the second feeding hopper.

7. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 1, characterized in that, The temperature-controlled barrel is equipped with multiple mixing devices. Each mixing device includes a combined threaded block, a mixing and kneading threaded block, a kneading block, a conveying block, and a shearing block arranged sequentially on a twin screw. The combined threaded block and the mixing and kneading threaded block are located inside the temperature-controlled barrel, which is connected to the second discharge bin. The kneading block, the conveying block, and the shearing block are located inside the temperature-controlled barrel, which is connected to the third discharge bin.

8. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 1, characterized in that, The temperature control cylinder is equipped with a drive device at one end. The drive device includes a gearbox, which is detachably connected to the temperature control cylinder via a spline connecting sleeve. The gearbox is rotatably connected to the motor unit via a gearbox and a coupling protector.

9. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 8, characterized in that, The other end of the temperature-controlled barrel is provided with a discharge device, which includes a screen changer. The screen changer is detachably connected to the temperature-controlled barrel. A heating coil is provided on the outside of the screen changer, and an extrusion die is provided outside the heating coil.

10. The twin-screw extruder for promoting the blending of antibacterial and anti-fogging masterbatch according to claim 8, characterized in that, The temperature-controlled barrel and the drive device are detachably mounted on the frame.

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