A mixing device and mixing system, mixing method for high viscosity resin polymer

Abstract

The application discloses a mixing device and mixing system for high-viscosity resin polymer and a mixing method. The mixing device comprises a mixing cavity and a stirring assembly arranged in the mixing cavity. The stirring assembly comprises a mixing shaft arranged in the center of the mixing cavity. The surface of the mixing shaft is provided with a plurality of mixing column teeth with high length-diameter ratios. The inner surface of the mixing cavity is fixedly provided with a plurality of mixing rod nails with high length-diameter ratios. The mixing column teeth and the mixing rod nails are arranged in a staggered mode. The outer side of the mixing cavity is provided with a first temperature control assembly. The mixing shaft is provided with a second temperature control assembly. The mixing column teeth with high length-diameter ratios and the mixing rod nails with high length-diameter ratios are used together. The shearing action of the two is utilized. The accurate temperature control of the first temperature control assembly and the second temperature control assembly can meet the high-speed and high-shear mixing requirements of the high-viscosity resin polymer, and the resin polymer with uniform mixing can be obtained.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials, and particularly relates to a mixing device, mixing system and mixing method for polymer materials. Background Technology

[0002] In the field of polymer materials, the molecular structures of different polymers endow materials with different properties. However, in practical applications, especially in specialized fields, materials are required to possess a variety of composite properties and appearance characteristics, such as color, reflectivity, electrical conductivity, thermal conductivity, dielectric properties, and heat resistance. This makes polymer doping and mixing through physical or chemical methods an indispensable material modification technique. Traditional doping and mixing of polymers with blends typically involves in-situ polymerization of polymers or stirring and shear dispersion mixing in reaction vessels or reactors. During production, achieving uniform dispersion and mixing of high-viscosity materials or modified substances is almost impossible. Inhomogeneous mixing can affect the performance or appearance uniformity of subsequent products, and for functional products, it may cause localized functional deficiencies, leading to product failure.

[0003] Furthermore, when using in-situ polymerization or reactor stirring, modified materials may adhere to the inner walls of the polymerization reactor or mixer, or remain in dead corners. For resin systems producing mixtures of different types of modified substances, incomplete cleaning or localized residues in the polymerization reactor or mixer may cause varying degrees of mixing between different types of resins, resulting in performance differences. Moreover, for reactive materials, the presence of modified materials in the polymerization reactor or mixer may cause problems such as gelation and clumping, affecting the quality of the final product. Thorough cleaning of the polymerization reactor and mixer usually requires a complete shutdown of the production line, incurring significant manpower and cleaning material costs, all of which indirectly increase product costs and affect the product's market competitiveness. For industries with high quality requirements or high fixed asset investment, cost control is even more difficult.

[0004] Currently, existing polymer mixing reaction devices all employ screw or helical blade mandrels, such as the patent with publication number CN115770537A, which uses a helical blade inner mandrel. Due to the large blade area and high resistance, this design only allows for low-speed shear mixing and is suitable for mixing low-speed, low-viscosity polymer resins, making it unsuitable for the uniform mixing of high-viscosity materials. Furthermore, the low shear rate and the large contact area between the material and the helical blades may cause reactive materials to adhere to or remain on the helical blades, leading to gelation or residue buildup. Additionally, although this patent uses a heat exchange jacket over the reaction tube to heat the material inside, it is not suitable for high-speed shear mixing because high-speed shear mixing would raise the temperature inside the reaction tube and make heat dissipation difficult, resulting in inconsistent temperature uniformity within the reaction tube. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies and defects mentioned in the background art above, and to provide a mixing device, mixing system and mixing method for high viscosity resin polymers. The mixing device, mixing system and mixing method can realize high-speed instantaneous mixing of high viscosity resin polymers, realize uniform mixing of materials in a uniform temperature field, and reduce the residue of materials in the mixing chamber.

[0006] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows:

[0007] A mixing device for high-viscosity resin polymers includes a mixing chamber and a stirring assembly located within the mixing chamber. The stirring assembly includes a mixing shaft disposed at the center of the mixing chamber, the surface of the mixing shaft being provided with a plurality of mixing column teeth with a high aspect ratio, and a plurality of mixing rods with a high aspect ratio being fixed on the inner surface of the mixing chamber. The mixing column teeth and mixing rods are arranged in a staggered manner. A first temperature control assembly for controlling the temperature inside the mixing chamber is provided on the outside of the mixing chamber, and a second temperature control assembly for reducing the temperature inside the mixing chamber and removing heat is provided on the mixing shaft.

[0008] In this invention, a high aspect ratio mixing column tooth and a high aspect ratio mixing rod are used together. By utilizing the shearing action of the two, and combined with the precise temperature control of the first and second temperature control components, the high-speed, high-shear mixing requirements of high-viscosity resin polymers can be met, resulting in a uniformly mixed resin polymer.

[0009] In the above-mentioned mixing device, preferably, the cross-sectional diameter of the mixing column teeth is 1-20 mm (the diameter is the minimum circumscribed circle diameter of the irregular cross-section), more preferably, the cross-sectional diameter is 4-8 mm, and the length-to-diameter ratio is 3-50, more preferably, the ratio is 5-10; the cross-sectional diameter of the mixing rods is 1-20 mm (the diameter is the minimum circumscribed circle diameter of the irregular cross-section), more preferably, the cross-sectional diameter is 4-8 mm, and the length-to-diameter ratio is 3-50, more preferably, the ratio is 5-10. Controlling the cross-sectional diameter and length-to-diameter ratio of the mixing column teeth and mixing rods within the above-mentioned range is beneficial for meeting the requirements of high-speed shear mixing of highly viscous materials.

[0010] In the aforementioned mixing device, preferably, the surface of the mixing column teeth has a reverse inclined surface for providing a reverse thrust to the material opposite to the material flow direction, and the surface of the mixing rod has a forward inclined surface for providing a forward thrust to the material in the same direction as the material flow direction. The adjacent mixing column teeth and mixing rod form a flow channel during high-speed mixing through opposing shearing inclined surfaces. During high-speed rotation, the reverse inclined surface can generate a reverse thrust around the mixing column teeth, forming convection with the overall material flow direction, which can prolong the residence time of the material between the mixing column teeth and enhance the mixing effect. The mixing rod has an arc-shaped inclined surface opposite to that of the mixing column teeth, whose main function is to form opposing shear with the mixing column teeth, allowing the material to generate a vortex-like effect between the two inclined surfaces (i.e., between the flow channels), increasing the mixing effect. The specific shape of the two arc-shaped inclined surfaces and the streamline state of the inclined surfaces can be simulated according to fluid mechanics to optimize the streamline shape suitable for specific materials, satisfying both the mixing effect and optimizing resistance.

[0011] In the above-mentioned mixing device, preferably, the gap between the end of the mixing column teeth and the inner wall of the mixing chamber is 0.1-5 mm, more preferably, the gap is 1-1.5 mm; the gap between the end of the mixing rod and the outer wall of the mixing shaft is 0.1-5 mm, more preferably, the gap is 1-1.5 mm; the gap between the mixing column teeth and the mixing rod is 0.1-5 mm, more preferably, the gap is 1-1.5 mm. The mixing device of the present invention mainly achieves material mixing through shearing. The gap between the mixing column teeth and the mixing rod cannot be controlled too large; otherwise, the shearing action between the mixing column teeth and the mixing rod will be relatively weak, making it difficult to achieve a uniform mixing effect. If the gap between the mixing column teeth and the mixing rod is too small, it will lead to excessive shearing, which will obstruct material flow and increase the resistance of the mixing shaft. Furthermore, for equipment machining accuracy, a very small gap will require very high machining precision, making equipment manufacturing more difficult. The gap between the end of the mixing column teeth and the inner wall of the mixing chamber, and the gap between the end of the mixing rod and the outer wall of the mixing shaft, cannot be too far; otherwise, the shearing action will be weak, and adhesion will be more likely to occur.

[0012] In the above-mentioned mixing device, preferably, the first temperature control component includes a first temperature control jacket disposed on the outer wall of the mixing chamber, the outer wall of the mixing chamber is provided with spiral guide vanes, and the first temperature control jacket is connected to a first temperature control medium inlet and a first temperature control medium outlet; the second temperature control component includes a second cooling cavity disposed inside the mixing shaft, the second cooling cavity is connected to a second cooling medium inlet and a second cooling medium outlet; a temperature probe is provided at the outlet end of the mixing chamber, and the temperature probe is signal-interlocked with the first temperature control component and the second temperature control component. The outer wall of the mixing chamber is provided with a flow channel in the form of spiral guide vanes, which provides a directional flow channel for the temperature control medium and increases the heat exchange area, thereby improving the heat exchange and temperature control effect of the material. The temperature probe can be one of a resistance temperature detector (RTD) or a thermocouple, more preferably a thermocouple temperature probe, and can be used in a jacketed or direct contact form with the material to monitor the material temperature.

[0013] This invention employs two sets of temperature control components, making it particularly suitable for the high-speed shear mixing requirements of high-viscosity materials. Under high shear conditions, the temperature inside the mixing chamber is generally high and difficult to dissipate, making conventional jacket-type heat exchangers insufficient to meet the requirements for a uniform temperature field. For high-speed shear mixing of high-viscosity materials, the first temperature control jacket primarily controls the temperature of the material to ensure it remains at the target temperature, maintaining a certain viscosity and flowability. The second temperature control component mainly functions to cool the material, removing the heat generated during high-speed mixing and providing a relatively stable temperature environment for the material, especially reactive materials. Specifically, this invention addresses the issue of high-viscosity materials generating heat during high-speed mixing, leading to a rise in material temperature. A second cooling cavity is incorporated inside the mixing shaft to facilitate temperature control. Because the material temperature at the center of the mixing chamber is difficult to dissipate due to its distance from the outer wall, especially in exothermic reactions, the high temperature in the center can lead to rapid gelation, which is detrimental to uniform mixing. Therefore, it is not advisable to place the second temperature control component, which serves a cooling function, on the outer wall of the mixing chamber. In a more preferred embodiment, the temperature probe is signal-interlocked with the first temperature control component and the second temperature control component. The first temperature control component and the second temperature control component can adjust the inflow rate of the medium in the first temperature control component and the second temperature control component according to the feedback data of the temperature probe, so as to ensure the uniformity of the temperature field.

[0014] In the aforementioned mixing device, preferably, the inner wall of the mixing chamber, the surface of the mixing shaft, the mixing column teeth, and the surface of the mixing rod are all mirror-polished and have a hardened plating layer. By implementing mirror polishing and a chrome-plated hardened layer, combined with the centrifugal force and high shear effect generated by the high-speed mixing shaft, the material residue within the mixing chamber, as in the prior art, can be minimized, achieving self-cleaning of the mixing chamber and other components. More preferably, all parts in contact with the material are mirror-polished and have a chrome-plated hardened layer.

[0015] Preferably, in the above-mentioned mixing device, the mixing chamber is provided with a main material injection pipe and a modified material injection pipe. The outlet of the modified material injection pipe is provided with an injection lock-up check valve to prevent material backflow. Multiple main material injection pipes and modified material injection pipes are arranged at different axial positions and radial angles along the mixing chamber. The end of the mixing chamber is provided with a material discharge pipe, which can be a bent pipe or a straight pipe. The above-mentioned material injection pipes can adopt threaded sealing or O-ring sealing. The material injection pipes can be provided with different injection ports along different radial angles of the mixing chamber. Unused injection ports are sealed with plugs to facilitate material feeding when multiple mixing devices are connected in series / parallel, and at different installation devices and installation angles. For modified material injection pipes, the mixing / reaction time of the material can be adjusted by selecting different injection nozzles; for the same material, multi-point dispersed injection can also be selected to prevent the problem of reduced mixing effect that may occur when injecting at a single point. At the same time, the injection nozzle adopts a one-way valve structure, which can effectively prevent the formation of reactive gel at the injection nozzle due to the high concentration of reactive material at the injection nozzle position, which would cause the injection nozzle to be blocked and affect the long-term stable operation of the production line.

[0016] In the aforementioned mixing device, preferably, a drive assembly for providing driving force is connected to the mixing shaft. The drive assembly includes a motor and a reducer. The reducer is one of a gear type, worm gear type, planetary type, cycloidal pin type, or RV reducer. The connection between the reducer and the mixing shaft is either direct drive or belt drive. The motor is either a frequency converter or a servo motor. More preferably, the drive assembly consists of a servo motor providing a speed of 500-2000 rpm and a precision reducer, with the mixing shaft and the precision reducer directly connected. The precision reducer can provide the high torque and precise speed control required for mixing high-viscosity materials. The direct connection between the reducer and the mixing shaft improves torque transmission efficiency and speed accuracy. The servo motor is an explosion-proof servo motor, and closed-loop speed control is implemented to ensure speed accuracy.

[0017] In the aforementioned mixing device, preferably, the mixing shaft and the mixing chamber are connected by a mechanical seal assembly, and a rotary joint is provided at the outer end of the mixing shaft. The mechanical seal assembly connection may include a dynamic / static sealing friction pair, a friction pair clamping device, and a friction pair cooling device; more preferably, the mechanical seal assembly uses a hard silicon carbide friction pair, which can effectively reduce the fine powder contaminants generated by friction during high-speed operation; the mechanical seal assembly itself is also equipped with an oil bath cooling system, which can prevent excessive temperature from occurring during high-speed operation, leading to seal failure; the mechanical seal uses packing compression combined with a thrust spring to ensure that the sealing ring still has a tight and efficient seal under high pressure in the mixing chamber. The rotary joint is one of a mechanical seal, hydraulic seal, or gap seal rotary joint that provides the medium inlet and outlet of the second cooling cavity and provides a sealing function, and more preferably a mechanical seal type rotary joint.

[0018] As a general technical concept, the present invention also provides a mixing system for high viscosity resin polymers, comprising a plurality of the above-described mixing devices connected in series, wherein the mixing devices are installed horizontally, obliquely, or vertically.

[0019] As a general technical concept, the present invention also provides a mixing method for the above-mentioned mixing system, employing two mixing devices connected in series for the uniform mixing of polyimide resin, doped filler, and catalyst. In the first mixing device, the polyimide resin and doped filler are first mixed at high speed at 1500 rpm to premix and disperse the doped filler and polyimide resin. In the first mixing device, the temperature inside the mixing chamber is maintained at 6-8°C by a first temperature control component and a second temperature control component to prevent the resin viscosity from being too high and affecting the mixing effect. Then, the mixed material is fed into the second mixing device, and the catalyst is simultaneously fed in for high-speed mixing at 1800 rpm. In the second mixing device, the temperature inside the mixing chamber is maintained at -5 to -10°C by a first temperature control component and a second temperature control component to ensure that the catalyst can be uniformly mixed with the resin while preventing the catalyst from rapidly reacting and forming gel in the mixing chamber at low temperature, thus affecting the uniformity of the cast film. The material discharged from the second mixing device is extruded from the casting die to obtain a chemically imide polyimide film doped with functional filler.

[0020] As a general technical concept, the present invention also provides a mixing system for high viscosity resin polymers, comprising a plurality of the above-described mixing devices, wherein the plurality of mixing devices are connected in series or parallel, and the mixing devices are installed horizontally, obliquely, or vertically.

[0021] As a general technical concept, the present invention also provides a mixing method for the above-mentioned mixing system, employing two mixing devices connected in parallel and then in series with one mixing device for the uniform mixing of polyimide resin, matting filler, color paste, and catalyst. The two parallel mixing devices are respectively used for high-speed mixing of polyimide resin and color paste, and polyimide resin and matting filler at 1500 rpm. Separate mixing can effectively avoid the degradation of the stability of the color paste solution caused by mixing the matting agent dispersion and the color paste, which would lead to color paste agglomeration and product inhomogeneity. In the two parallel mixing devices, through the first The temperature control components maintain the temperature inside the mixing chamber at 6-8℃. The materials from the two parallel mixing devices are combined into the mixing device connected in series with them. At the same time, the catalyst is input for high-speed mixing at 1800 rpm. In the series mixing device, the temperature inside the mixing chamber is maintained at -5 to -10℃ by the first and second temperature control components. This allows the catalyst to be mixed evenly with the resin while preventing the catalyst from reacting rapidly in the mixing chamber to form a gel, which would affect the uniformity of the cast film. The material discharged from the series mixing device is extruded from the casting die to obtain a colored matte polyimide film.

[0022] In this invention, the outlet of the mixing device for high-viscosity resin polymers can be directly connected to the mechanical die, or multiple mixing devices can be connected in series / parallel and then connected to the mechanical die.

[0023] The mixing device of the present invention is preferably installed in a horizontal manner to prevent uneven sedimentation of the modified material with a higher specific gravity during high-speed mixing.

[0024] The viscosity of the high-viscosity resin of the present invention can be 1000-5000P, and the resin type can be epoxy resin, polyurethane, PET under high temperature, PP and polyimide prepolymer resin and other polymer resins.

[0025] The mixing device for high-viscosity resin polymers of the present invention has the following main working process: A motor provides hybrid power and controls the mixing speed. After being reduced in speed by a reducer, the motor transmits power to the mixing shaft. The main material is transported into the mixing chamber through the main material injection pipe, and the modified material is transported into the mixing chamber through the modified material injection pipe. Under the stirring and mixing of the mixing shaft, and under the shearing force provided by the mixing column teeth and mixing rods, the materials are mixed. Finally, the mixture is discharged through the material discharge pipe at the end of the mixing chamber. Throughout the process, the driving force for the material flow comes from a high-pressure pump at the front end of the equipment, such as a melt pump, hydraulic diaphragm pump, plunger pump, screw pump, etc.

[0026] The mixing device for high-viscosity resin polymers of the present invention is mainly suitable for rapid / instantaneous mixing and modification of high-viscosity polymers and modified substances (including functional fillers, color masterbatches, catalysts, chemical modifiers, etc.) in the terminal pipeline. Because the device has a high rotation speed, it can provide strong shear force to the polymer and modified substances to achieve the purpose of dispersion and uniform mixing. Especially for most high-viscosity, non-Newtonian fluids, high-speed shearing can produce a shear thinning effect, which significantly reduces the viscosity of the polymer, which is beneficial for mixing and dispersing modified substances.

[0027] To meet the requirements of rapid / instantaneous mixing modification of high-viscosity resins, this invention provides mixing rods at the material contact points on the inner wall of the mixing chamber to provide shearing action to the material. Several groups of mixing rods can be arranged on the inner wall of the mixing chamber according to the different physical properties of the material, evenly distributed along the circumference of the inner wall. The cross-sectional diameter of the mixing rods ranges from 1-20 mm, more preferably 4-8 mm, with an aspect ratio of 3-50, and even more preferably 5-10, to meet the requirements of shear dispersion. Simultaneously, this invention provides mixing teeth on the outer surface of the mixing shaft that cooperate with the mixing rods in the mixing chamber to generate shearing action on the material. Several groups of mixing teeth can be arranged on the outer surface of the mixing shaft according to the different physical properties of the material, corresponding to the mixing rods. The cross-sectional diameter of the mixing teeth ranges from 1-20 mm, more preferably 4-8 mm, with an aspect ratio of 3-50, and even more preferably 5-10, to meet the requirements of shear dispersion. The gap between the mixing column teeth and the mixing rods can be set to different values ​​according to the material characteristics, such as 0.1-5mm, and more preferably, the gap is 1-1.5mm. Compared with conventional spiral blades, the mixing rods and mixing column teeth have a smaller contact area with the material and less resistance, which is beneficial to the high-speed mixing of the mixing shaft.

[0028] Meanwhile, since the mixing rods and mixing teeth have a smaller contact area with the material compared to conventional spiral blades, and all contact points with the material (such as the inner wall of the mixing chamber; the outer surfaces of the mixing shaft, mixing rods and mixing teeth, etc.) are mirror polished and have a chrome-plated hardening layer, combined with the centrifugal force brought about by the high speed of the mixing shaft, the material residue in the mixing chamber can be avoided as much as possible, thus achieving self-cleaning of the mixing chamber and other components.

[0029] Compared with the prior art, the advantages of the present invention are as follows:

[0030] 1. The mixing device for high-viscosity resin polymers of the present invention uses mixing rods in the mixing chamber and mixing teeth on the mixing shaft. Strong shear force is generated between the mixing rods and the mixing teeth, which is beneficial to the penetration and interweaving of high-viscosity resin and dopants. Furthermore, for non-Newtonian fluid resins, high rotation speed can produce a shear thinning effect, reduce the apparent viscosity of the resin, and greatly improve the mixing effect of the material.

[0031] 2. The mixing device for high-viscosity resin polymers of the present invention, by setting a first temperature control component and a second temperature control component on the mixing chamber and the mixing shaft respectively, can, on the one hand, remove the heat generated during the shear dispersion process and stabilize the temperature rise of the material and the equipment; on the other hand, by setting different medium temperatures, it can provide a stable temperature environment for the mixing and reaction of the material, ensuring the consistency and controllability of the final product material.

[0032] 3. The mixing device and system for high-viscosity resin polymers of the present invention can be arranged in a vertical, inclined, or horizontal modular stacking manner. It can be used individually or in multi-stage series or parallel configurations to adapt to different resin doping and mixing methods, thus having a wider range of applications and adapting to different types of mixing conditions. For example, for reactive material doping and mixing, the resin and modifier can be first mixed at high speed in the upstream device, and then the reactive or catalytic material can be injected into the downstream mixing device. After high-speed mixing and reaction, the mixture is discharged from the outlet and extruded through a mechanical die. For materials requiring different mixing times, the mixing time can be adjusted by the number of series stages or the barrel length. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is an overall structural diagram of the mixing device for high-viscosity resin polymers according to the present invention.

[0035] Figure 2 This is an assembly diagram of the mixing chamber and mixing shaft in the mixing device for high-viscosity resin polymers of the present invention.

[0036] Figure 3 This is a structural diagram of the mixing shaft and mixing column teeth of the mixing device for high viscosity resin polymers according to the present invention.

[0037] Figure 4 This is a structural diagram of the mixing chamber and mixing rod of the mixing device for high-viscosity resin polymers according to the present invention.

[0038] Figure 5 This is a schematic diagram showing the engagement of the mixing column teeth and mixing rods in the mixing device for high-viscosity resin polymers according to the present invention.

[0039] Figure 6 This is a process flow diagram of the mixing apparatus for high-viscosity resin polymers according to the present invention.

[0040] Figure 7 The diagram shows the structure of the mixing device for high-viscosity resin polymers of the present invention in multiple series and series-parallel configurations (a in the diagram is two series, horizontal configuration; b in the diagram is three series-parallel, horizontal configuration; c in the diagram is two series, vertical configuration; d in the diagram is three series-parallel, vertical configuration).

[0041] Legend

[0042] 1. Material discharge pipe; 2. Mixing shaft; 201. Mixing column teeth; 2011. Reverse inclined plane; 3. Mixing chamber; 301. Mixing rod; 3011. Forward inclined plane; 302. Spiral guide vane; 4. First temperature-controlled medium inlet; 5. First temperature-controlled jacket; 6. First temperature-controlled medium outlet; 7. Second cooling cavity; 8. Second cooling medium inlet; 9. Second cooling medium outlet; 10. Main material injection pipe; 11. Servo motor; 12. Precision reducer; 13. Mechanical seal assembly; 14. Rotary joint; 15. Guide channel; 16. Modified material injection pipe. Detailed Implementation

[0043] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0044] It should be noted that when a component is described as being "fixed to, attached to, connected to or connected to" another component, it can be directly fixed to, attached to, connected to or connected to the other component, or it can be indirectly fixed to, attached to, connected to or connected to the other component through other intermediate connectors.

[0045] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0046] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0047] Example 1:

[0048] like Figures 1-5 As shown, the mixing device for high viscosity resin polymers in this embodiment includes a mixing chamber 3 and a stirring assembly located inside the mixing chamber 3. The stirring assembly includes a mixing shaft 2 located at the center of the mixing chamber 3. The surface of the mixing shaft 2 is provided with a plurality of mixing column teeth 201 with a high aspect ratio. The inner surface of the mixing chamber 3 is fixed with a plurality of mixing rods 301 with a high aspect ratio. The mixing column teeth 201 and the mixing rods 301 are staggered. A first temperature control assembly for controlling the temperature inside the mixing chamber 3 is provided outside the mixing chamber 3. A second temperature control assembly for reducing the temperature inside the mixing chamber 3 and removing heat is provided on the mixing shaft 2.

[0049] like Figures 3-5 As shown, in this embodiment, the cross-sectional diameter of the mixing column tooth 201 is 1-20 mm, and the length-to-diameter ratio is 3-50; the cross-sectional diameter of the mixing rod 301 is 1-20 mm, and the length-to-diameter ratio is 3-50. The surface of the mixing column tooth 201 has a reverse inclined surface 2011 for providing a reverse thrust to the material opposite to the material flow direction, and the surface of the mixing rod 301 has a forward inclined surface 3011 for providing a forward thrust to the material in the same direction as the material flow. Adjacent mixing column teeth 201 and mixing rod 301 form a guide channel 15 for high-speed mixing and stirring through the relatively arranged shearing inclined surfaces. The gap between the end of the mixing column tooth 201 and the inner wall of the mixing chamber 3 is 1-1.5 mm; the gap between the end of the mixing rod 301 and the outer wall of the mixing shaft 2 is 1-1.5 mm; the gap between the mixing column tooth 201 and the mixing rod 301 is 1-1.5 mm.

[0050] In this embodiment, the first temperature control component includes a first temperature control jacket 5 disposed on the outer wall of the mixing chamber 3, and a spiral guide vane 302 disposed on the outer wall of the mixing chamber 3. The first temperature control jacket 5 is connected to a first temperature control medium inlet 4 and a first temperature control medium outlet 6. The second temperature control component includes a second cooling cavity 7 disposed inside the mixing shaft 2, and a second cooling medium inlet 8 and a second cooling medium outlet 9 are connected to the second cooling cavity 7. A temperature probe is disposed at the outlet end of the mixing chamber 3, and the temperature probe is signal-interlocked with the first temperature control component and the second temperature control component.

[0051] In this embodiment, the inner wall of the mixing chamber 3, the surface of the mixing shaft 2, the mixing column teeth 201 and the surface of the mixing rod 301 are all mirror polished and have a hardened coating to make the surface roughness Ra 0.05.

[0052] In this embodiment, the mixing chamber 3 is provided with a main material injection pipe 10 and a modified material injection pipe 16. The outlet of the modified material injection pipe 16 is provided with an injection lock-up check valve to prevent material backflow. Multiple main material injection pipes 10 and modified material injection pipes 16 are provided at different axial positions and different radial angles along the mixing chamber 3. The end of the mixing chamber 3 is provided with a material discharge pipe 1, which is a bent pipe or a straight pipe.

[0053] In this embodiment, a drive assembly for providing driving force is connected to the hybrid shaft 2. The drive assembly consists of a servo motor 11 and a precision reducer 12 that provide a speed of 1000-2000 rpm. The hybrid shaft 2 and the precision reducer 12 are directly connected.

[0054] In this embodiment, the mixing shaft 2 and the mixing chamber 3 are connected by a mechanical seal assembly 13, and a rotary joint 14 is provided at the outer end of the mixing shaft 2.

[0055] More specifically, in normal use, the mixing device for high-viscosity resin polymers in this embodiment is powered by a servo motor 11, which also controls the mixing speed. The servo motor 11, after being reduced in speed by a precision reducer 12, transmits power to the mixing shaft 2, causing it to rotate at high speed and possess a strong torque capable of resisting material shear forces. The main material is then transported into the mixing chamber 3 through the main material injection pipe 10. Generally, one or more main material injection pipes 10 are provided to accommodate the instantaneous and continuous mixing of multiple main materials. The mixing chamber 3 has a first temperature control jacket 5 on its exterior for temperature control. Inside the mixing chamber 3 are mixing rods 301 (such as fixed pins) that provide shearing action. The diameter of the mixing rods 301 can be 4mm, and the length-to-diameter ratio can be 6, used to form a high-speed mixing mechanism with the mixing pins 201 on the mixing shaft 2. The mixing shaft 201 has a shearing action, with a diameter of 4mm and a length-to-diameter ratio of 6. The mixing shaft 2 has a second cooling cavity 7 inside to control the temperature of the mixing shaft 2. The mechanical seal assembly 13 provides material sealing at the shaft end during the rotation of the mixing shaft 2. During high-speed rotation, dopants, reactive materials, or catalytic materials are injected from the modified material injection pipe 16 and mixed with the main material at high speed and continuously. Finally, the materials are discharged from the internal mirror-polished and chrome-plated material discharge pipe 1. The material discharge pipe 1 can be directly connected to the rear forming die device. After continuous mixing, the materials can be directly processed to obtain the desired product shape. During normal operation, the temperature of the materials can be monitored by the temperature probe on the mixing chamber 3 and associated with the first and second temperature control components for closed-loop temperature control, which can effectively control the temperature of the materials.

[0056] like Figure 7As shown, the mixing system for high-viscosity resin polymers in this embodiment includes multiple mixing devices as described above, which are connected in series and are installed horizontally, obliquely, or vertically.

[0057] The mixing method of the above-mentioned mixing system employs two mixing devices connected in series for the uniform mixing of polyimide resin, doped filler, and catalyst. In the first mixing device, the polyimide resin is first mixed with the doped filler at high speed to premix and disperse the doped filler and polyimide resin. In the first mixing device, the temperature inside the mixing chamber 3 is maintained at 6-8°C by the first and second temperature control components. Then, the mixed material is fed into the second mixing device, and the catalyst is simultaneously fed in for high-speed mixing. In the second mixing device, the temperature inside the mixing chamber 3 is maintained at -5 to -10°C by the first and second temperature control components. The material discharged from the second mixing device is extruded from the casting die to obtain a chemically imide polyimide film doped with functional filler.

[0058] like Figure 7 As shown, the mixing system for high-viscosity resin polymers in this embodiment includes multiple mixing devices as described above, which are connected in series and parallel, and are installed horizontally, obliquely, or vertically.

[0059] The mixing method of the above-mentioned mixing system adopts a configuration of two mixing devices connected in parallel and then connected in series with a mixing device for uniform mixing of polyimide resin, matte filler, color paste, and catalyst. The two parallel mixing devices are used to perform high-speed mixing of polyimide resin and color paste, and polyimide resin and matte filler, respectively. In the two parallel mixing devices, the temperature inside the mixing chamber 3 is maintained at 6-8°C by the first and second temperature control components. The materials from the two parallel mixing devices are combined into the mixing device connected in series with them, and the catalyst is simultaneously input for high-speed mixing. In the mixing device connected in series, the temperature inside the mixing chamber 3 is maintained at -5 to -10°C by the first and second temperature control components. The material discharged from the mixing device connected in series is extruded from the casting die to obtain a colored matte polyimide film.

[0060] The mixing system of this embodiment can be arranged in a vertical or horizontal modular stacking manner, and can be configured in multi-stage series or series-parallel configurations to adapt to different resin doping and mixing methods. For reactive material doping and mixing, the resin and the modified material can be mixed at high speed in the upstream unit, and then the reactive or catalytic material can be injected into the downstream mixing unit. After high-speed mixing and reaction, the mixture is discharged from the outlet and extruded through a mechanical die. Alternatively, for materials requiring different mixing times, the mixing time can be adjusted by the number of series stages or the barrel length to adapt to different types of mixing conditions.

[0061] The mixing system for high-viscosity resin polymers used in this embodiment employs a two-stage tandem assembly to mix the resin of the corona-resistant polyimide film with corona-resistant fillers and a chemical imidization catalyst, such as... Figure 6 As shown, the specific implementation is as follows: PMDA, ODA, and PDA are used in a DMAc solvent for prepolymerization to produce polyimide precursor resin. The viscosity of the polyimide resin is controlled, and it is pumped into the mixing chamber 3 from the main material injection pipe 10 of the first-stage mixing device via a metering pump. Additionally, nano-Al2O3 modified slurry is injected into the mixing chamber 3 from two different angles of the modified material injection pipe 16 of the first-stage mixing device via a metering pump. The resin to modified slurry ratio is controlled at 10:3. High-speed mixing is performed under a set rotation speed. The first temperature control jacket 5 of the mixing chamber 3 and the second cooling cavity 7 of the mixing shaft 2 are respectively... The material is independently temperature-controlled using a refrigerant at 7°C. After mixing, the material enters the second-stage mixing device through the material discharge pipe 1. In the modified material injection pipe 16 of the second-stage mixing device, the chemical imide catalyst is injected at three different angles using a metering pump. The ratio of resin to chemical imide catalyst is controlled at 10:4. The mixing speed is also controlled. The first temperature control jacket 5 of the mixing chamber 3 and the second cooling cavity 7 of the mixing shaft 2 are independently temperature-controlled using a refrigerant at -5°C. Finally, the material enters the polyimide casting die from the material discharge pipe 1 for casting and film formation. After drying and imidization, a corona-resistant polyimide film is obtained.

[0062] In this embodiment, the viscosity of the polyimide precursor resin is 5000P, the rotation speed of the first-stage mixing device is 1500rpm, and the diameter of the mixing column teeth 201 and the mixing rods 301 in the first-stage mixing device is 4mm, with an aspect ratio of 6; the rotation speed of the second-stage mixing device is 1800rpm, and the diameter of the mixing column teeth 201 and the mixing rods 301 in the second-stage mixing device is 4mm, with an aspect ratio of 6; finally, a corona-resistant polyimide film is obtained through a casting die and casting equipment.

[0063] Example 2:

[0064] Compared to Example 1, in the first-stage mixing device, the length-to-diameter ratio of the mixing column teeth 201 and the mixing rod nail 301 is 4; in the second-stage mixing device, the length-to-diameter ratio of the mixing column teeth 201 and the mixing rod nail 301 is 4, and other conditions are the same as in Example 1.

[0065] Example 3:

[0066] Compared to Example 1, the viscosity of the polyimide precursor resin was 1000P, and other conditions were the same as in Example 1.

[0067] Example 4:

[0068] Compared to Example 2, the viscosity of the polyimide precursor resin was 1000P, and other conditions were the same as in Example 2.

[0069] Comparative Example 1:

[0070] Compared to Example 1, the rotation speed of the first-stage mixing device is 100 rpm, the rotation speed of the second-stage mixing device is 150 rpm, and other conditions are the same as in Example 1.

[0071] Comparative Example 2:

[0072] Compared to Example 1, the rotation speed of the first-stage mixing device is 100 rpm, and the length-to-diameter ratio of the mixing column teeth 201 and the mixing rods 301 in the first-stage mixing device is 4; the rotation speed of the second-stage mixing device is 150 rpm, and the length-to-diameter ratio of the mixing column teeth 201 and the mixing rods 301 in the second-stage mixing device is 4, and other conditions are the same as in Example 1.

[0073] Comparative Example 3:

[0074] Compared to Comparative Example 1, the viscosity of the polyimide precursor resin was 1000P, and other conditions were the same as those in Comparative Example 1.

[0075] Comparative Example 4:

[0076] Compared to Comparative Example 2, the viscosity of the polyimide precursor resin was 1000P, and other conditions were the same as those in Comparative Example 1.

[0077] Comparative Example 5:

[0078] Compared to Example 1, the hybrid cylindrical teeth 201 and the hybrid rod nail 301 adopt a cylindrical shape, while other conditions are the same as in Example 1.

[0079] Comparative Example 6:

[0080] Compared to Example 1, the mixing shaft 2 is not equipped with a second temperature control component for reducing the temperature inside the mixing chamber 3 and removing heat, while other conditions are the same as in Example 1.

[0081] Comparative Example 7:

[0082] Compared to Example 1, the surface roughness Ra of the inner wall of the mixing chamber 3, the surface of the mixing shaft 2, the mixing column teeth 201 and the mixing rod nail 301 is 2.3, and other conditions are the same as in Example 1.

[0083] Comparative Example 8:

[0084] Compared to Example 1, the surface roughness Ra of the inner wall of the mixing chamber 3, the surface of the mixing shaft 2, the mixing column teeth 201 and the mixing rod 301 is 2.3. The mixing column teeth 201 and the mixing rod 301 adopt a cylindrical shape. Other conditions are the same as in Example 1.

[0085] Comparative Example 9:

[0086] Compared to Example 1, no mixing rod 301 is provided in the mixing chamber 3, and other conditions are the same as in Example 1.

[0087] Comparative Example 10:

[0088] Compared to Example 1, no mixing rod 301 is provided in the mixing chamber 3, and no second temperature control component is provided on the mixing shaft 2 to reduce the temperature inside the mixing chamber 3 and remove heat. Other conditions are the same as in Example 1.

[0089] Tables 1-3 show the performance data of the above embodiments and comparative examples. For uneven mixing, fillers generally exhibit agglomeration, which leads to filler agglomeration defects in the final film product. Therefore, this index is used to evaluate the uniformity of filler mixing. Gel defects are mainly caused by insufficient shearing, resulting in gel material residue on the surfaces of the mixing pins 201 and 301. When the gel grows to a certain size, it will detach due to shearing, forming a gel point curve on the film surface. Therefore, this is also an indicator for evaluating the self-cleaning effect of the mixing pins 301.

[0090] Table 1: Density of agglomeration and gelation defects in Examples 1-4 and Comparative Examples 1-4

[0091]

[0092] Table 2: Density of Agglomeration Defects and Gel Defects in Comparative Examples 5, 7, and 8

[0093]

[0094] Table 3: Density of Agglomeration Defects and Gel Defects in Comparative Examples 6, 9, and 10

[0095]

[0096] Evaluation of the embodiments and comparative examples:

[0097] As shown in Table 1, for different resin viscosities of 5000P and 1000P, Examples 1 and Comparative Example 3 showed the best filler mixing effect, anti-gelling effect, and self-cleaning effect. Both viscosities achieved good mixing effect. However, the slurry mixing effect and catalyst mixing effect were poor at low speed. By selecting mixing column teeth 201 and mixing rod nails 301 with an aspect ratio of 6, the slurry and catalyst mixing effect was better than that with an aspect ratio of 4 due to their large shearing effect.

[0098] As can be seen from the data in Table 2, mirror polishing of the mixing chamber 3 and the mixing shaft 2 (including the mixing column teeth 201 and the mixing rod nails 301) can effectively avoid residual resin gel on the surface. However, whether or not polishing is performed has little difference in the uniformity of slurry mixing.

[0099] As can be seen from the data in Table 3, installing the mixing rod 301 inside the mixing chamber 3 can effectively improve the uniformity of mixing of slurry and resin, and controlling the temperature of the mixing shaft 2 at a constant -5℃ can effectively prevent local temperature accumulation in the mixing shaft 2, which would cause the reactive materials to quickly form gel on the surface.

Claims

1. A method suitable for the production of polyimide film by the chemical imidization method, characterized in that, The method uses a single mixing system for imidization of polyimide resin, the mixing system includes two mixing devices, the two mixing devices are connected in series, and the mixing devices are installed in a horizontal, inclined or vertical manner; The mixing system is used for uniform mixing of polyimide resin, doping fillers and catalysts, in the first mixing device, the polyimide resin is first mixed with the doping fillers at a high speed to pre-mix and disperse the doping fillers and the polyimide resin, in the first mixing device, the temperature in the mixing cavity (3) is maintained at 6-8℃ by the first temperature control assembly and the second temperature control assembly; then the mixed material is input into the second mixing device, and the catalyst is input at the same time for high-speed mixing, in the second mixing device, the temperature in the mixing cavity (3) is maintained at -5~-10℃ by the first temperature control assembly and the second temperature control assembly; the material discharged from the second mixing device is extruded from a casting die to obtain a chemical imine method polyimide film doped with functional fillers; The mixing device includes a mixing cavity (3) and a stirring assembly located in the mixing cavity (3), the stirring assembly includes a mixing shaft (2) arranged at the center of the mixing cavity (3), a plurality of high-length-diameter-ratio mixing column teeth (201) are arranged on the surface of the mixing shaft (2), a plurality of high-length-diameter-ratio mixing rod nails (301) are fixedly arranged on the inner surface of the mixing cavity (3), the mixing column teeth (201) and the mixing rod nails (301) are arranged in a staggered manner, a first temperature control assembly for controlling the temperature in the mixing cavity (3) is arranged on the outside of the mixing cavity (3), and a second temperature control assembly for reducing the temperature in the mixing cavity (3) and removing heat is arranged on the mixing shaft (2); The surface of the mixing column tooth (201) is provided with a reverse arc inclined surface (2011) for providing a reverse thrust opposite to the flow direction of the material, and the surface of the mixing rod nail (301) is provided with a forward arc inclined surface (3011) for providing a forward thrust in the same direction as the flow direction of the material; the mixing column tooth (201) and the mixing rod nail (301) arranged adjacent to each other form a flow guide channel (15) during high-speed mixing and stirring through the oppositely arranged shearing inclined surfaces.

2. The method of claim 1, wherein, The cross-sectional diameter of the mixing column tooth (201) is 1-20mm, and the ratio of the length to the diameter is 3-50; the cross-sectional diameter of the mixing rod nail (301) is 1-20mm, and the ratio of the length to the diameter is 3-50.

3. The method of claim 1, wherein, The gap between the end of the mixing column tooth (201) and the inner wall of the mixing cavity (3) is 0.1-5mm, the gap between the end of the mixing rod nail (301) and the outer wall of the mixing shaft (2) is 0.1-5mm, and the gap between the mixing column tooth (201) and the mixing rod nail (301) is 0.1-5mm.

4. The method of claim 1, wherein, The first temperature control assembly comprises a first temperature control jacket (5) arranged on the outer wall surface of the mixing cavity (3), the outer wall surface of the mixing cavity (3) is provided with a spiral flow guide vane (302), and the first temperature control jacket (5) is connected with a first temperature control medium inlet (4) and a first temperature control medium outlet (6); the second temperature control assembly comprises a second cooling cavity (7) arranged in the mixing shaft (2), and the second cooling cavity (7) is connected with a second cooling medium inlet (8) and a second cooling medium outlet (9); the outlet end of the mixing cavity (3) is provided with a temperature probe, and the temperature probe is signal interlocked with the first temperature control assembly and the second temperature control assembly.

5. The method of claim 1, wherein, The inner wall of the mixing cavity (3), the surface of the mixing shaft (2), the surface of the mixing column tooth (201) and the surface of the mixing rod spike (301) are mirror-polished, and a hard plating layer is arranged on the surfaces.

6. The method of claim 1, wherein, The mixing cavity (3) is provided with a main material injection pipe (10) and a modified material injection pipe (16), the outlet of the modified material injection pipe (16) is provided with an injection lock one-way valve for preventing material backflow, and the main material injection pipe (10) and the modified material injection pipe (16) are provided with a plurality of positions along the axial direction of the mixing cavity (3) and a plurality of angles along the radial direction; the end of the mixing cavity (3) is provided with a material discharge pipe (1), and the material discharge pipe (1) is a bent pipe or a straight pipe.

7. The method of claim 1, wherein, The mixing shaft (2) is connected with a driving assembly for providing driving force, the driving assembly is a servo motor (11) and a precision speed reducer (12) for providing a rotating speed of 500-2000 rpm, and the mixing shaft (2) is directly connected with the precision speed reducer (12).

8. A method for producing a polyimide film by a chemical imidization method, characterized by, The method uses a single mixing system to perform imidization treatment on the polyimide resin, the mixing system comprises a plurality of mixing devices, and the plurality of mixing devices are connected in series and in parallel, and the mixing devices are installed in a horizontal, inclined or vertical manner; The mixing system is used for uniformly mixing polyimide resin, matt filler, color paste and catalyst, two parallel mixing devices are respectively used for high-speed mixing of polyimide resin and color paste and polyimide resin and matt filler, in the two parallel mixing devices, the temperature in the mixing cavity (3) is maintained at 6-8℃ through the first temperature control assembly and the second temperature control assembly; the materials in the two parallel mixing devices are combined into a mixing device connected in series, and a catalyst is input for high-speed mixing, in the series-connected mixing device, the temperature in the mixing cavity (3) is maintained at -5~-10℃ through the first temperature control assembly and the second temperature control assembly; and the material discharged from the series-connected mixing device is extruded from a casting die to obtain a colored matte polyimide film. The mixing device comprises a mixing cavity (3) and a stirring assembly located in the mixing cavity (3), the stirring assembly comprises a mixing shaft (2) located in the center of the mixing cavity (3), the surface of the mixing shaft (2) is provided with a plurality of mixing column teeth (201) with high length-diameter ratio, the inner surface of the mixing cavity (3) is fixedly provided with a plurality of mixing rod pins (301) with high length-diameter ratio, the mixing column teeth (201) and the mixing rod pins (301) are arranged in a staggered manner, the outer side of the mixing cavity (3) is provided with a first temperature control assembly for controlling the temperature in the inner cavity of the mixing cavity (3), and the mixing shaft (2) is provided with a second temperature control assembly for reducing the temperature in the inner cavity of the mixing cavity (3) and carrying away heat. The surface of the mixing column tooth (201) is provided with a reverse arc slope (2011) for providing a reverse thrust opposite to the flow direction of the material, and the surface of the mixing rod pin (301) is provided with a positive arc slope (3011) for providing a positive thrust in the same direction as the flow direction of the material; the mixing column teeth (201) and the mixing rod pins (301) arranged adjacently form a flow guide channel (15) during high-speed mixing and stirring through the oppositely arranged shearing slopes.

9. The method of claim 8, wherein, The cross-sectional diameter of the mixing column tooth (201) is 1-20 mm, and the ratio of the length to the diameter is 3-50; the cross-sectional diameter of the mixing rod pin (301) is 1-20 mm, and the ratio of the length to the diameter is 3-50.

10. The method of claim 8, wherein, The gap between the end of the mixing column tooth (201) and the inner wall of the mixing cavity (3) is 0.1-5 mm, the gap between the end of the mixing rod pin (301) and the outer wall of the mixing shaft (2) is 0.1-5 mm, and the gap between the mixing column tooth (201) and the mixing rod pin (301) is 0.1-5 mm.

11. The method of claim 8, wherein, The first temperature control assembly comprises a first temperature control jacket (5) arranged on the outer wall surface of the mixing cavity (3), the outer wall surface of the mixing cavity (3) is provided with a spiral flow guide piece (302), the first temperature control jacket (5) is connected with a first temperature control medium inlet (4) and a first temperature control medium outlet (6); the second temperature control assembly comprises a second cooling cavity (7) arranged in the interior of the mixing shaft (2), the second cooling cavity (7) is connected with a second cooling medium inlet (8) and a second cooling medium outlet (9); the outlet end of the mixing cavity (3) is provided with a temperature probe, and the temperature probe is signal interlocked with the first temperature control assembly and the second temperature control assembly.

12. The method of claim 8, wherein, The inner wall of the mixing cavity (3), the surface of the mixing shaft (2), the surface of the mixing column tooth (201) and the surface of the mixing rod pin (301) are mirror-polished and provided with a hard plating layer.

13. The method of claim 8, wherein, The mixing cavity (3) is provided with a main material injection pipe (10) and a modified material injection pipe (16), the outlet of the modified material injection pipe (16) is provided with an injection lock one-way valve for preventing material backflow, the main material injection pipe (10) and the modified material injection pipe (16) are provided with multiple pipes at different axial positions and different radial angles of the mixing cavity (3); the end of the mixing cavity (3) is provided with a material discharge pipe (1), the material discharge pipe (1) is a bent pipe or a straight pipe.

14. The method of claim 8, wherein, The mixing shaft (2) is connected with a driving assembly for providing driving force, the driving assembly is a servo motor (11) and a precision speed reducer (12) for providing a rotating speed of 500-2000 rpm, and the mixing shaft (2) and the precision speed reducer (12) are directly connected.

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