Solid-phase post-polymerization device for bio-based polyamide

Abstract

The utility model discloses a solid-phase post-polymerization device for bio-based polyamide. The solid-phase post-polymerization device comprises a kettle body, a supporting structure and a rotary driving structure, a reaction chamber for solid-phase polymerization of bio-based polyamide is arranged inside the kettle body; the supporting structure is supported below the kettle body so that the lower part of the kettle body is suspended; the supporting structure is rotationally connected with the kettle body; the rotary driving structure is connected with the kettle body and drives the kettle body to rotate relative to the supporting structure; the kettle body further comprises a temperature control system for controlling the temperature in the reaction chamber, a vacuum system for controlling the pressure in the reaction chamber and a sampling device, the reaction temperature in the reaction chamber is 5-40 DEG C below the melting point temperature of the bio-based polyamide, and the sampling device comprises a flow guide pipe communicated with the inside and the outside of the kettle body and multi-stage control valves connected in series along the flow guide pipe. The reaction kettle has the advantages that the problems of adhesion of high-viscosity fluid to the inner wall of the kettle body and stirring are solved, a material sample can be obtained in real time for testing, and PDI of bio-based polyamide is reduced.

Description

Technical Field

[0001] This utility model relates to the field of bio-based polyamide technology, and in particular to a solid-phase post-polymerization apparatus for bio-based polyamides. Background Technology

[0002] Polyamide (PA) is a class of polymers containing -CO-NH- repeating units. It possesses excellent mechanical properties, wear resistance, heat resistance, corrosion resistance, dyeing properties, and good biocompatibility, and is widely used in biomedicine, electronic devices, and automotive interiors. Typically, the monomers used to prepare polyamides are chemically synthesized from downstream products of petroleum cracking.

[0003] Currently, bio-based polyamides have received strong support and development from the government and enterprises due to their advantages of being green, environmentally friendly, and using renewable raw materials. The raw materials for synthesizing polyamides are mainly diacids and diamines, and preparation methods include melt polymerization, solution polymerization, interfacial polymerization, and solid-state polymerization. Commonly used bio-based diacids include 1,4-succinic acid, itaconic acid, 2,5-furandicarboxylic acid, 1,6-adipic acid, and dimer acids, while commonly used bio-based diamines include 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, and 1,10-decanediamine, often obtained through bacterial or microbial fermentation. However, the prepared bio-based polyamides generally suffer from a wide molecular weight distribution, which directly affects the melt viscosity and flowability during spinning, easily clogging the spinneret and reducing the physical properties of bio-based islanded microfibers. Therefore, adopting appropriate methods to reduce the molecular weight distribution index (PDI) of bio-based polyamides is crucial for the spinning process and physical properties of bio-based islanded microfibers. Utility Model Content

[0004] This invention provides a solid-phase post-polymerization apparatus for bio-based polyamides, which avoids the problems of high-viscosity fluids adhering to the inner wall of the reactor and stirring, and can obtain material samples for testing in real time, thereby reducing the PDI of bio-based polyamides.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A solid-phase post-polymerization apparatus for bio-based polyamides includes a vessel body, a support structure, and a rotary drive structure. The vessel body contains a reaction chamber for solid-phase polymerization of bio-based polyamides. The support structure is positioned below the vessel body, allowing it to be suspended in the air, and is rotatably connected to the vessel body. The rotary drive structure is connected to the vessel body and drives the vessel body to rotate relative to the support structure. The vessel body also includes a temperature control system for controlling the internal temperature of the reaction chamber, a vacuum system for controlling the internal pressure of the reaction chamber, and a sampling device. The reaction temperature within the reaction chamber is 5 to 40 degrees Celsius below the melting point of the bio-based polyamide. The sampling device includes a guide pipe connecting the inside and outside of the vessel body and a multi-stage control valve connected in series along the guide pipe.

[0007] The reaction temperature of the solid-phase post-polymerization apparatus is selected to be 5-40℃ below the melting point of bio-based polyamide. Compared with melt polymerization reactions above the melting point, this effectively suppresses the thermal decomposition process and side reactions, and avoids problems such as high-viscosity fluid adhering to the inner wall of the reactor and stirring issues. The alternating control of multi-stage control valves allows for the real-time and multiple acquisition of solid-phase post-polymerization samples for subsequent testing without disrupting the original experimental vacuum and temperature conditions, thus reducing the PDI of bio-based polyamide.

[0008] Preferably, the multi-stage control valve includes at least a first control valve and a second control valve spaced apart, with a spacing of 5-15 cm between them. By opening the first control valve and keeping the second control valve closed, the reaction sample enters the guide tube between the first and second control valves. Closing the first control valve and opening the second control valve allows for the acquisition of the reaction sample for subsequent testing. By alternating the use of the control valves, solid-phase post-polymerization samples can be obtained multiple times in real time for subsequent testing without disrupting the original experimental vacuum and temperature conditions.

[0009] Preferably, the temperature control system includes a heating device, a temperature sensing device, and a temperature controller. The heating device includes an electromagnetic induction coil wound circumferentially around the outer wall of the vessel. The temperature sensing device includes a temperature sensor disposed within the reaction chamber. The temperature controller is electrically connected to the temperature sensor. The electromagnetic induction coil generates a magnetic field that heats the vessel; the coil itself does not generate heat. The temperature controller, temperature sensor, and heating device form a closed-loop temperature control system, achieving reliable temperature control within the vessel.

[0010] Preferably, the heating device also includes a heat insulation layer covering the outside of the electromagnetic induction coil, which heats the temperature inside the reaction chamber to the reaction temperature. The heat insulation layer improves the thermal efficiency inside the reactor, reaching over 90%, effectively reducing heat and energy loss.

[0011] Preferably, the temperature controller includes a temperature coupler and a temperature control panel, which are electrically connected. The temperature control panel is programmed to perform gradient temperature increases based on the characteristics of the sample. The temperature control system has a programmed gradient temperature control function, which can ensure uniform heating of bio-based polyamide powder or granular samples and prevent localized overheating of the sample.

[0012] Preferably, the vacuum system includes a pressure control path connecting to the reaction chamber. This pressure control path includes a main pressure control path, a pressure boosting branch, and a pressure relief branch. The pressure boosting and pressure relief branches are connected in parallel to the main pressure control path. The main pressure control path is connected to the vessel body and equipped with a pressure detector. The pressure relief branch is equipped with a pressure relief control valve, and the pressure boosting branch is equipped with a pressure boosting control valve and a vacuum pump. The vacuum system reliably regulates the internal pressure of the vessel body through the pressure boosting branch formed by the vacuum pump and the pressure boosting control valve, and the pressure relief branch containing the pressure relief control valve.

[0013] Preferably, the vacuum system and the temperature controller are located at opposite ends of the vessel's axial direction. This creates a counterweight, ensuring the stability of the vessel's rotation.

[0014] Preferably, a feed cover and a discharge cover are provided on opposite sides of the vessel body. When the feed cover is opened, the material enters the reaction chamber, and the discharge cover is equipped with a guide pipe. The feed cover and discharge cover are provided on opposite sides of the vessel body, which can serve as a counterweight to further improve the stability of the vessel body's rotation.

[0015] Preferably, the rotary drive structure includes a drive motor and a gearbox, with the drive motor, gearbox, and vessel body connected by a transmission. This enables reliable rotation of the vessel body, and the rotation speed can be easily controlled via the gearbox.

[0016] Preferably, the support structure includes a first support and a second support spaced apart, with a rotating shaft fixed at both ends of the vessel body. A rotation drive structure drives the rotating shaft, which rotatably connects the first support and the second support to support the vessel body. This allows for the rotatable support of the vessel body, avoiding interference from components such as multi-stage control valves and vacuum pumps relative to the ground.

[0017] The beneficial effects of the above solution will be described in detail with reference to the accompanying drawings and the following embodiments. Attached Figure Description

[0018] Figure 1 This is a front view of a solid-phase post-polymerization apparatus for bio-based polyamides according to one embodiment of the present invention.

[0019] Figure 2 This is a front cross-sectional view of the vessel in a solid-phase post-polymerization apparatus for bio-based polyamides according to another embodiment of this utility model.

[0020] In the diagram: 1. Drive motor; 2. Gearbox; 3-1. First support; 3-2. Second support; 4. Temperature coupler; 5-1. Feeding vessel cover; 5-2. Discharge vessel cover; 6. Pressure detector; 7-1. Pressure boosting control valve; 7-2. Pressure relief control valve; 7-3. First control valve; 7-4. Second control valve; 8. Sealing shaft; 9. Vacuum pump; 10. Vessel body; 11. Guide pipe; 12. Temperature control panel; 13. Rotating shaft; 14. Electromagnetic induction coil; 15. Thermal insulation layer. Detailed Implementation

[0021] like Figures 1 to 2 As shown, one embodiment of this utility model discloses a solid-state post-polymerization apparatus for bio-based polyamides, comprising a vessel body 10, a support structure, and a rotary drive structure. The vessel body 10 has a reaction chamber inside for solid-state polymerization of bio-based polyamides. The support structure is supported below the vessel body 10 so that the vessel body is suspended in the air below, and the support structure is rotatably connected to the vessel body 10. The rotary drive structure is connected to the vessel body 10 and drives the vessel body 10 to rotate relative to the support structure. The vessel body 10 also includes a temperature control system for controlling the internal temperature of the reaction chamber, a vacuum system for controlling the internal pressure of the reaction chamber, and a sampling device. The reaction temperature inside the reaction chamber is 5 to 40 degrees below the melting point of the bio-based polyamide. The sampling device includes a guide pipe 11 connecting the inside and outside of the vessel body 10 and a multi-stage control valve connected in series along the guide pipe 11.

[0022] In this application, the reaction chamber within the reactor is used for the solid-state post-polymerization of bio-based polyamide. A supporting structure suspends the reactor body, which is rotatably mounted on this structure. A rotational drive mechanism provides rotational power to the reactor via a motor and other transmission components. To ensure reliable polymerization, a temperature control system and a vacuum system are used to stably control the temperature and pressure within the reactor. During polymerization, the temperature within the reaction chamber is controlled at 4 to 40 degrees Celsius below the melting point of the bio-based polyamide. Compared to typical melt polymerization reactions above the melting point, this effectively suppresses thermal decomposition and side reactions, avoiding the adhesion of high-viscosity fluid to the reactor wall and the problems associated with stirring. Alternating control of multi-stage valves allows for the real-time and multiple acquisition of post-polymerized solid-state samples for subsequent testing without disrupting the original experimental vacuum and temperature conditions, thus reducing the PDI (particulate density index) of the bio-based polyamide.

[0023] One embodiment of this utility model discloses a solid-state post-polymerization device for bio-based polyamides, comprising a vessel body 10, a support structure, and a rotary drive structure. The vessel body 10 has a reaction chamber inside for solid-state polymerization of bio-based polyamides. The support structure is positioned below the vessel body 10, allowing it to be suspended in the air, and is rotatably connected to the vessel body 10. The rotary drive structure is connected to the vessel body 10 and drives the vessel body 10 to rotate relative to the support structure. The rotary drive structure includes a drive motor 1 and a reduction gearbox 2, which are connected to the vessel body via a transmission mechanism. This ensures reliable rotation of the vessel body, and the rotation speed is easily controlled by the reduction gearbox 2. The support structure includes a first support 3-1 and a second support 3-2 spaced apart. Coaxial rotating shafts 13 are fixed at both ends of the vessel body 10. The rotary drive structure drives the rotating shafts 13, which are rotatably connected to the first support 3-1 and the second support 3-2 via bearings to support the vessel body 10. This allows for the rotatable installation of the vessel body, preventing interference from components such as multi-stage control valves and vacuum pumps relative to the ground that could affect the rotation of the vessel body.

[0024] The vessel body 10 also includes a temperature control system for controlling the internal temperature of the reaction chamber, a vacuum system for controlling the internal pressure of the reaction chamber, and a sampling device. The reaction temperature inside the reaction chamber is 5 to 40 degrees below the melting point of the bio-based polyamide. The sampling device includes a guide pipe 11 connecting the inside and outside of the vessel body 10 and a multi-stage control valve connected in series along the guide pipe 11.

[0025] The multi-stage control valve includes a first control valve 7-3 and a second control valve 7-4 spaced apart, with a spacing of 5-15 cm between the first control valve 7-3 and the second control valve 7-4.

[0026] The temperature control system includes a heating device, a temperature sensing device, and a temperature controller. The heating device includes an electromagnetic induction coil 14 wound circumferentially around the outer wall of the vessel and a thermal insulation layer 15 covering the electromagnetic induction coil 14. The heating device heats the temperature inside the reaction chamber to the reaction temperature. The thermal insulation layer 15 improves the thermal efficiency inside the vessel, reaching over 90%, effectively reducing heat and energy loss and minimizing the risk of burns from external high temperatures. The temperature sensing device includes a temperature sensor installed inside the reaction chamber, and the temperature controller is electrically connected to the temperature sensor. The electromagnetic induction coil 14 generates a magnetic field that heats the vessel 10; the coil itself does not heat up. The temperature controller, temperature sensor, and heating device form a closed-loop temperature control system, achieving reliable temperature control inside the vessel 10.

[0027] The temperature controller includes a temperature coupler 4 and a temperature control panel 12, which are electrically connected. The temperature control panel 12 is programmed to perform gradient temperature increases based on the characteristics of the sample. The temperature control system has a programmed gradient temperature control function, which can ensure that the bio-based polyamide powder or granular sample is heated evenly and prevent local overheating of the sample.

[0028] The vacuum system includes a pressure control path connecting to the reaction chamber. This path comprises a main pressure control path, a pressure boosting branch, and a pressure relief branch. The pressure boosting and pressure relief branches are connected in parallel to the main pressure control path. The main pressure control path connects to the vessel body and is equipped with a pressure detector 6. The pressure relief branch is equipped with a pressure relief control valve 7-2, and the pressure boosting branch is equipped with a pressure boosting control valve 7-1 and a vacuum pump 9. A sealing shaft 8 is installed between the pressure boosting control valve 7-1 and the vacuum pump 9. The vacuum system reliably regulates the internal pressure of the vessel body through the pressure boosting branch formed by the vacuum pump 9 and the pressure boosting control valve 7-1, and the pressure relief branch containing the pressure relief control valve 7-2.

[0029] Figure 1 In the reactor body 10, a temperature coupler 4 and a temperature control panel 12 are located at the upper left corner, connected together. A pressure detector 6 is located at the upper right corner, with a pressure relief control valve 7-2 to its right. A pressure boosting control valve 7-1 bypasses the pressure detector 6 and the pressure relief control valve 7-2, with a sealing shaft 8 and a vacuum pump 9 to its right. A feed cover 5-1 is located on the upper side of the reactor body between the temperature controller and the vacuum system. Feed is introduced into the reaction chamber when the feed cover is opened.

[0030] A discharge cover 5-2 is provided on the lower side of the vessel body 10, while the feed cover 5-1 and the discharge cover 5-2 are located on opposite sides of the vessel body 10. They can serve as counterweights to improve the stability of the vessel body 10's rotation.

[0031] The guide tube 11 passes through the discharge vessel cover 5-2, and the diameter of the guide tube 11 below the vessel body is 10-50mm. Below the guide tube 11 are a first control valve 7-3 and a second control valve 7-4, with a spacing of 5-15cm between them, used to place the sample. Opening the first control valve 7-3 allows the reaction sample to enter the guide tube between the first control valve 7-3 and the second control valve 7-4. Closing the first control valve 7-3 and opening the second control valve 7-4, by alternating the use of the control valves, allows for real-time acquisition of the reaction sample for subsequent testing without disrupting the original experimental vacuum and temperature conditions.

[0032] It should be noted that, due to the integrated design of the discharge vessel cover, guide pipe, first control valve, and second control valve, the moment of inertia on this side is greater than that on the side where the feed vessel cover is located. Therefore, when the vessel body 10 is not in operation, the discharge vessel cover corresponds to the lower side of the vessel body, and the feed vessel cover corresponds to the upper side of the vessel body. Figure 1 The state of the vessel 10 shown is the state when the vessel 10 is not in operation.

[0033] The method of using this utility model is as follows: Close the pressure boosting control valve 7-1, the pressure relief control valve 7-2, the first control valve 7-3, and the second control valve 7-4. Add bio-based polyamide into the reactor body 10 through the feed lid 5-1, and close the lid 5-1. Open the pressure boosting control valve 7-1, start the vacuum pump 9, and after reaching the required vacuum level for the reaction, set the temperature control panel 12. Turn on the drive motor 1, and use the reduction gearbox 2 to control the rotation speed of the reactor body 10. When the temperature stabilizes, the solid-phase post-polymerization reaction begins. When sampling at different reaction times, stop the rotation of the reactor body 10, with the discharge lid 5-2 at its lowest point, open the first control valve 7-3, and allow the sample to pass through the guide pipe 11 via the first control valve 7-3. After closing the first control valve 7-3, open the second control valve 7-4 to obtain the solid-phase post-polymerization sample for subsequent testing. When the solid-phase polymerization reaction is complete, stop rotating the reactor body 10, and position the discharge reactor lid 5-2 at its lowest point. After the reactor body 10 cools to room temperature, close the pressure boosting control valve 7-1 and the vacuum pump 9, and open the pressure relief control valve 7-2 to release pressure. After pressure relief is complete, close the pressure relief control valve 7-2. Finally, open the first control valve 7-3 and the second control valve 7-4 to remove the solid-phase polymerized product.

[0034] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A solid-phase post-polymerization apparatus for bio-based polyamides, characterized in that, Includes the vessel body, support structure, and rotary drive structure; The reactor body is equipped with a reaction chamber inside for solid-phase polymerization of bio-based polyamide; The support structure is positioned below the vessel body so that the vessel body is suspended in the air below, and the support structure is rotatably connected to the vessel body. The rotary drive structure is connected to the vessel body and drives the vessel body to rotate relative to the support structure. The vessel also includes a temperature control system for controlling the internal temperature of the reaction chamber, a vacuum system for controlling the internal pressure of the reaction chamber, and a sampling device. The reaction temperature inside the reaction chamber is 5 to 40 degrees below the melting point of the bio-based polyamide. The sampling device includes a guide pipe connecting the inside and outside of the vessel and a multi-stage control valve connected in series along the guide pipe. The temperature control system includes a heating device, a temperature sensing device, and a temperature controller. The heating device includes an electromagnetic induction coil wound circumferentially on the outer wall of the vessel. The temperature sensing device includes a temperature sensor installed inside the reaction chamber. The temperature controller is electrically connected to the temperature sensor. The vacuum system includes a pressure control path connecting the reaction chamber. The pressure control path includes a main pressure control path, a pressure boosting branch, and a pressure relief branch. The pressure boosting branch and the pressure relief branch are connected in parallel to the main pressure control path. The main pressure control path is connected to the vessel and is equipped with a pressure detector. The pressure relief branch is equipped with a pressure relief control valve, and the pressure boosting branch is equipped with a pressure boosting control valve and a vacuum pump.

2. A solid-state post-polymerization apparatus for bio-based polyamides according to claim 1, characterized in that, The multi-stage control valve includes at least a first control valve and a second control valve spaced apart, with the interval between the first control valve and the second control valve being 5-15 cm.

3. The solid-phase post-polymerization apparatus for bio-based polyamides according to claim 1, characterized in that, The heating device also includes a heat insulation layer covering the outside of the electromagnetic induction coil, and the heating device heats the temperature inside the reaction chamber to the reaction temperature.

4. The solid-phase post-polymerization apparatus for bio-based polyamides according to claim 1, characterized in that, The temperature controller includes a temperature coupler and a temperature control panel, which are electrically connected. The temperature control panel sets a program to perform gradient heating according to the characteristics of the sample.

5. A solid-state post-polymerization apparatus for bio-based polyamides according to claim 1, characterized in that, The vacuum system and temperature controller are located at opposite ends of the vessel body along its axial direction.

6. A solid-state post-polymerization apparatus for bio-based polyamides according to any one of claims 1 to 5, characterized in that, The reactor body is provided with a feed cover and a discharge cover on opposite sides. When the feed cover is opened, the material is fed into the reaction chamber, and the discharge cover is provided with a guide pipe.

7. A solid-state post-polymerization apparatus for bio-based polyamides according to any one of claims 1 to 5, characterized in that, The rotary drive structure includes a drive motor and a gearbox, and the drive motor, gearbox and vessel body are connected by a transmission.

8. A solid-state post-polymerization apparatus for bio-based polyamides according to any one of claims 1 to 5, characterized in that, The support structure includes a first support and a second support spaced apart. A rotating shaft is fixed at both ends of the vessel body along its axial direction. A rotation drive structure drives the rotating shaft, and the rotating shaft rotatably connects the first support and the second support to support the vessel body.

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