An antimicrobial medical catheter gas-liquid co-assist forming mold and method

Abstract

The application discloses an antibacterial medical catheter gas-liquid co-assisted forming die and a method thereof. The die comprises a connecting pipe, a flow channel changing pipe, a machine head body, an extrusion outlet die and an outer die in sequence, and an extrusion channel is formed in the above structure units and is in communication with each other. Heating equipment and temperature sensing equipment are further installed. A melt flow dividing cone, a flow guide core rod body and a shaping rod body are sequentially assembled in the extrusion channel from left to right. An auxiliary gas mixing chamber and an inner auxiliary gas flow channel are formed between the melt flow dividing cone and the flow guide core rod body. The melt flow dividing cone is fixed by an inner auxiliary gas inlet bolt. A through gas inlet channel is arranged in the inner auxiliary gas inlet bolt. An inner auxiliary gas flow channel is arranged in the melt flow dividing cone. A powder metallurgy porous ring is arranged in the extrusion outlet die, and an outer liquid auxiliary liquid inlet bolt is inserted into the hollow. The gas-liquid co-assisted system is introduced to reduce the extrusion viscous resistance of the medical catheter, and the medical catheter is endowed with antibacterial properties and other functions, so that the die problem of high-quality extruded functional medical microcatheters is solved.

Description

Technical Field

[0001] This invention belongs to the field of antibacterial medical catheter preparation and processing technology, specifically relating to an antibacterial medical catheter gas-liquid co-assisted molding mold and method. Background Technology

[0002] Extrusion molding is characterized by high production efficiency and excellent continuity, and is widely used in the molding of medical catheters. Compared with traditional tubing extrusion dies, the processing of catheter extrusion dies is more complex due to the small flow channel size and complex structure. In the traditional extrusion molding process, when the polymer melt is extruded under the strong action of the extruder, it is not only prone to inlet effect, but also to defects such as extrusion swell, extrusion deformation, melt fracture, and tensile deformation. Furthermore, as medical catheters are used, medical accidents such as catheter infections are prone to occur, thus placing higher demands on the functionality of medical catheters.

[0003] To imbue medical catheters with antibacterial properties, passive and active antibacterial methods are commonly employed. Passive antibacterial properties are achieved by modifying the surface morphology or free energy through surface modification to prevent bacterial adhesion. Active antibacterial properties are achieved by using antibacterial agents to kill bacteria or inhibit bacterial reproduction. In other words, surface modification and treatment methods are used to imbue medical catheters with antibacterial properties. Traditional antibacterial layer preparation requires processes such as coating and curing with surface compounds to fix the antibacterial layer onto the surface of the medical catheter. This preparation method is complex, and the resulting thin film is unstable and prone to detachment, severely affecting the performance of the medical microtubules.

[0004] To successfully prepare medical catheters with antibacterial properties, the extrusion mold and method need to be redesigned to achieve co-extrusion molding of antibacterial nanomaterials and melt. This not only improves the extrusion quality of medical catheters and eliminates defects such as extrusion swell, but also ensures the formation of a stable antibacterial layer on the surface of the medical catheter, giving it self-antibacterial properties. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing antibacterial medical catheter extrusion molding dies and methods by proposing an antibacterial medical catheter gas-liquid co-assisted molding die and method. This antibacterial medical catheter gas-liquid co-assisted molding die and method changes horizontal extrusion to vertical extrusion and introduces a gas-liquid co-assisted system. While reducing the viscous resistance of medical catheter extrusion, it endows medical catheters with antibacterial and other functions, thus solving the mold problem of high-quality extrusion of functional medical catheters.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] An antibacterial medical catheter gas-liquid co-assisted forming mold includes a connecting pipe, a flow channel deflector, a die head, an extrusion die, and an outer die connected in sequence. These structural units are fixedly connected in pairs by fasteners, forming interconnected extrusion channels. A heating device for heating the melt and a temperature sensor for measuring the temperature during the extrusion process are installed on the forming mold.

[0008] The extrusion channel is equipped with a melt splitter cone, a guide mandrel, and a shaping mandrel from left to right. The melt splitter cone is installed in the internal channel of the die head, and the guide mandrel is installed in the internal channel of the extrusion die. The guide mandrel is fastened to the end of the melt splitter cone by a threaded connector. The guide mandrel has a cavity inside. One end of the shaping mandrel passes through the cavity and is fixedly connected to the melt splitter cone by a thread. The gaps between the melt splitter cone, the guide mandrel, the die head, and the extrusion die form a melt flow channel.

[0009] The gap between the melt splitting cone and the guide core rod forms an auxiliary gas mixing chamber and a gas flow channel. The melt splitting cone is fixed inside the head body by several sets of internal gas auxiliary inlet bolts. The internal gas auxiliary inlet bolts are provided with a through-flow inlet channel. The melt splitting cone is provided with an internal auxiliary gas flow channel. The inlet channel and the internal auxiliary gas flow channel are connected and finally converge into the auxiliary gas mixing chamber.

[0010] A powder metallurgical porous ring is installed inside the extrusion die, which is fixed inside the extrusion die by an outer die and fasteners. Several sets of external liquid auxiliary inlet bolts are inserted into the end of the extrusion die. The external liquid auxiliary inlet bolts pass through the outside of the extrusion die and communicate with its internal channel. The external liquid auxiliary inlet bolts, the extrusion die, the outer die, and the powder metallurgical porous ring form an auxiliary liquid mixing chamber. A through inlet channel is provided inside the external liquid auxiliary inlet bolts.

[0011] Preferably, the connecting pipe and the flow channel reversing pipe are perpendicular to each other, and the internal channels of the flow channel reversing pipe, the die head, the extrusion die, and the outer die are on the same horizontal line, so that the melt is extruded from a horizontal to a vertical direction. This structural arrangement allows the overall die to form a right-angle extrusion mode, which can further reduce the space of the overall equipment and make it more compact.

[0012] Preferably, through holes are made in the flow channel reversing pipe, the head body, and the melt diverting cone to form a gas recovery channel. Exhaust bolts are fastened to the flow channel reversing pipe to connect the gas recovery channel to an external gas recovery system for recovering auxiliary gas and nanoparticles.

[0013] Preferably, several groups of internal air-assisted air inlet bolts are evenly distributed around the die head body, and several external liquid-assisted liquid inlet bolts are evenly distributed around the extrusion die.

[0014] Preferably, the heating device includes a heating ring for the connecting pipe, a heating ring for the flow channel reversing pipe, a heating ring for the die head body, and a heating ring for the extrusion die, which are respectively wrapped around the connecting pipe, the flow channel reversing pipe, the die head body, and the extrusion die. The temperature sensing device includes a temperature sensor for the connecting pipe, a temperature sensor for the flow channel reversing pipe, a temperature sensor for the die head body, and a temperature sensor for the extrusion die, which are respectively embedded in the connecting pipe, the flow channel reversing pipe, the die head body, and the extrusion die.

[0015] Preferably, the heating rings of the connecting pipe, the flow channel reversing pipe, the die head, and the extrusion die are all symmetrical semi-ring structures, and the two halves of each heating ring are fastened together by screws; and through holes are provided at the temperature sensor positions to facilitate the installation of the corresponding temperature sensors.

[0016] This invention also discloses a gas-liquid co-assisted molding method for antibacterial medical microtubes using the above-mentioned mold as a molding mold, comprising the following steps:

[0017] Step 1: Raw material processing for extrusion: Use a constant temperature drying oven to dry the polymer elastomer and remove moisture;

[0018] Step 2, Auxiliary fluid preparation: Add antibacterial nanoparticles to the aerosol generator, and introduce gas at a certain flow rate and pressure to evenly disperse the antibacterial nanoparticles in the gas flow. Connect the gas to the internal gas-assisted air intake bolt. Mix the hydrophilic nanoparticles with the auxiliary liquid, and introduce the mixed liquid into the external liquid-assisted liquid intake bolt.

[0019] Step 3: Start the extruder: After adding the extrusion material, turn on the power to the extruder and at the same time turn on the heating equipment and temperature sensing equipment on the molding die. Use the heating equipment to heat each part to the set temperature in stages, and use the temperature sensing equipment to measure the temperature of each component in real time.

[0020] Step 4, Material Extrusion: The raw material is melted in the extruder to form a melt. Under the pushing action of the extrusion screw, it enters the forming die. After passing through the connecting pipe and the flow channel deflector, the extrusion direction changes from horizontal to vertical and enters the die head. Under the action of the melt diverting cone, it enters the flow channel. Then, under the action of the guide mandrel and the extrusion die, it forms a guide tube shape in the extrusion die. The melt reaches the gas-liquid co-assisted area. First, the gas containing antibacterial nanoparticles enters the internal auxiliary gas flow in the melt diverting cone through the air intake channel of the internal gas auxiliary intake bolt. The gas flows through the gas channel to the auxiliary gas mixing chamber. During the extrusion of the melt, an air cushion film layer is formed on the inner surface of the conduit, embedding antibacterial nanoparticles into the surface and interior of the conduit. Then, the auxiliary liquid containing hydrophilic nanoparticles enters the auxiliary liquid mixing chamber through the inlet channel of the external liquid inlet bolt. Through the permeation effect of the powder metallurgy porous ring, the auxiliary liquid is delivered to the outer surface of the melt, forming an auxiliary liquid layer. The nanoparticles are embedded into the interior of the melt surface. Then, under the combined action of the shaping rod and the external die, a conduit that meets the functional and dimensional requirements is extruded.

[0021] Step 5: Cooling and Shaping Process: After the microtube is extruded from the die, it passes through a cooling system to obtain a shaped medical catheter with antibacterial function.

[0022] Preferably, the airflow entering the internal gas-assisted intake bolt and the liquid entering the external liquid-assisted intake bolt can be adjusted to control the flow rate and pressure of the auxiliary fluid and form a stable auxiliary film layer.

[0023] Preferably, depending on the needs of medical catheter fabrication, different functional nanoparticles can be replaced to give the catheter different functions, and medical catheters with different size parameters can be fabricated by replacing extrusion dies and flow guide mandrels with different structural parameters.

[0024] Compared with the prior art, the beneficial effects of the present invention include:

[0025] Existing antibacterial medical catheter molding processes are complex and cumbersome, and the antibacterial layer formed on the surface is unstable. The antibacterial medical catheter extrusion die of this invention, combined with an auxiliary gas system, an auxiliary liquid system, and an exhaust system, can effectively fuse and embed antibacterial nanoparticles with the melt surface during the gas-liquid co-assisted extrusion molding of medical microtubes. This is achieved by using an auxiliary liquid to form a stable antibacterial layer on the surface and subsurface of the medical catheter, thus realizing the preparation of an antibacterial medical catheter.

[0026] This invention relates to a gas-liquid co-assisted molding die for antibacterial medical catheters. Through an external liquid-internal gas mode, a stable auxiliary film layer is formed between the surface of the medical catheter and the inner wall of the die during the extrusion process. This effectively reduces the adhesive resistance during melt extrusion, essentially eliminates extrusion swelling, and improves extrusion quality.

[0027] The mold of the present invention performs catheter forming and antibacterial surface functional layer forming simultaneously during catheter forming, avoiding the complex process of performing the surface functional layer after catheter preparation in the current technology and the possible contamination caused thereby, thus improving production efficiency. Moreover, the antibacterial material and the surface of the medical catheter form the antibacterial surface functional layer when the catheter is in the molten state, at which time the surface energy is high, the adsorption capacity is strong, and it is easy to form a strong and durable surface functional layer.

[0028] This invention employs a gas-liquid co-assisted mode, with external liquid and internal gas, which avoids the loss and waste of external nanoparticles. Furthermore, the internal gas is connected to an external gas recovery system through a gas recovery channel to recover the gas containing antibacterial nanoparticles, thereby reducing production costs and increasing the utilization rate of nanoparticles. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the gas-liquid co-assisted molding die structure for an antibacterial medical catheter according to the present invention;

[0030] Figure 2 yes Figure 1 Sectional views (a: AA section view; b: BB section view).

[0031] Illustration: 1-Flange; 2-Heating ring for connecting pipe; 3-Temperature sensor for connecting pipe; 4-Connecting pipe; 5-Flow channel deflector; 6-Stabilizing ring A; 7-Stabilizing ring B; 8-Heating ring for die head body; 9-Inner gas auxiliary air inlet bolt; 10-Guide mandrel body; 11-Die pressure ring fastening bolt; 12-Extrusion die; 13-Powder metallurgy porous ring; 14-Outer die fastening bolt; 15-Shaping rod body; 16-Outer die; 17 - Auxiliary liquid mixing chamber; 18- External liquid auxiliary inlet bolt; 19- Extrusion die heating ring; 20- Extrusion die temperature sensor; 21- Die pressure ring; 22- Auxiliary gas mixing chamber; 23- Die head body temperature sensor; 24- Melt splitter cone; 25- Die head body; 26- Retaining ring fastening bolt; 27- Flow channel reversing tube heating ring; 28- Flow channel reversing tube temperature sensor; 29- Gas recovery channel; 30- Exhaust bolt.

[0032] In the description of this invention, the terms “center,” “upper,” “lower,” “left,” “right,” “vertical,” “horizontal,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0033] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Detailed Implementation

[0034] The specific embodiments of the present invention are described in detail below with reference to the technical solutions and accompanying drawings.

[0035] like Figure 1 and Figure 2 As shown, an antibacterial medical catheter gas-liquid co-assisted forming mold includes a connecting pipe 4, a flow channel deflector 5, a die head 25, an extrusion die 12, and an outer die 16 connected in sequence, with interconnected extrusion channels formed within the above structural units. The connecting pipe 4 and the flow channel deflector 5 are perpendicular to each other, causing the molten raw material to be extruded from a horizontal to a vertical direction. The internal channels of the flow channel deflector 5, the die head 25, the extrusion die 12, and the outer die 16 are on the same horizontal line. The overall mold adopts a right-angle extrusion mode, which can further reduce the space of the overall equipment, making it more compact. Through the action of the venting system, the pressure uniformity of the inner and outer walls of the tube is maintained, further eliminating melt expansion and improving the forming quality of the medical microtube.

[0036] The connecting pipe 4 is a structure that connects the entire mold to the external single-screw extruder. The connecting pipe 4 is tightly connected to the die head body 25 of the mold through the flow channel reversing pipe 5, and the entire extrusion mold is connected to the outlet of the single-screw extruder through the flange 1. The connecting pipe 4 and the flow channel reversing pipe 5 are fixedly connected by threads. The flow channel reversing pipe 5 is fixedly connected to the die head body 25 through the retaining rings A6 and B7 under the action of the retaining ring fastening bolts 26. The extrusion die 12 is fastened to the die head body 25 under the combined action of the die pressure ring 21 and the die pressure ring fastening bolts 11.

[0037] Inside the extrusion channel, from top to bottom, are assembled a melt diverting cone 24, a guide mandrel 10, and a shaping mandrel 15. The melt diverting cone 24 is installed in the internal channel of the die head 25, and the guide mandrel 10 is installed in the internal channel of the extrusion die 12. The guide mandrel 10 is securely connected to the end of the melt diverting cone 24 via a threaded connector. The guide mandrel 10 has a cavity, and one end of the shaping mandrel 15 passes through the cavity and is fixedly connected to the melt diverting cone 24 via a thread. The gaps between the melt diverting cone 24, the guide mandrel 10, the die head 25, and the extrusion die 12 form a melt flow channel. The guide mandrel 10, the shaping mandrel 15, and the extrusion die 12 are all installed using detachable connectors, allowing for the replacement of different specifications and models according to different production requirements.

[0038] The gap between the melt diverting cone 24 and the guide core rod 10 forms an auxiliary gas mixing chamber 22 and an internal auxiliary gas flow channel. The auxiliary gas mixing chamber 22 is located in the area where the end of the melt diverting cone 24 connects to the guide core rod 10. The melt diverting cone 24 is fixed inside the head body 25 by several sets of internal auxiliary gas inlet bolts 9. The internal auxiliary gas inlet bolts 9 are connected to an external aerosol generator. A through-flow inlet channel is provided inside the internal auxiliary gas inlet bolts 9. An internal auxiliary gas flow channel is provided inside the melt diverting cone 24. The inlet channel and the internal auxiliary gas flow channel are connected and finally converge in the auxiliary gas mixing chamber 22. In practice, antibacterial nanoparticles are introduced into the aerosol generator to form a uniformly dispersed airflow containing antibacterial nanoparticles. The gas containing antibacterial nanoparticles enters the inner auxiliary gas flow channel in the melt diversion cone 24 through the air intake channel of the inner auxiliary gas intake bolt 9, and reaches the auxiliary gas mixing chamber 22. When the melt is extruded through the gas flow channel, an air cushion film layer is formed on the inner surface, and the antibacterial nanoparticles are embedded in the surface and interior of the melt, so that the conduit has antibacterial function.

[0039] A powder metallurgical porous ring 13 is installed inside the extrusion die 12, which is fixed inside the extrusion die 12 by an outer die 16 and outer die fastening bolts 14. Several sets of external liquid auxiliary inlet bolts 18 are inserted in a circumferential manner at the end of the extrusion die 12. The external liquid auxiliary inlet bolts 18 pass through the outside of the extrusion die 12 and communicate with its internal channel. The space where the external liquid auxiliary inlet bolts 18 and the inner cavity of the extrusion die 12 are connected is the auxiliary liquid mixing chamber 17. Specifically, the external liquid auxiliary inlet bolts 18, the extrusion die 12, the outer die 16, and the powder metallurgical porous ring 13 form the auxiliary liquid mixing chamber 17. The external liquid auxiliary inlet bolts 18 have a through-flow inlet channel, which is connected to the external liquid mixing chamber. After entering the flow channel from the air inlet, the auxiliary liquid undergoes vertical turning and flow inertia. The mixing chamber is used to mix the auxiliary fluid, making its flow field stable and uniform. In practice, hydrophilic nanoparticles are mixed with liquid in a liquid mixing chamber to form an auxiliary liquid. The auxiliary liquid containing hydrophilic nanoparticles is introduced into the auxiliary liquid mixing chamber 17 through the liquid inlet channel of the external liquid auxiliary inlet bolt 18. The auxiliary liquid is delivered to the outer surface of the melt through the permeation effect of the powder metallurgy porous ring 13 to form an auxiliary liquid layer. The nanoparticles are embedded in the interior of the melt surface to form a hydrophilic function.

[0040] Several internal gas-assisted air inlet bolts 9 (four in this embodiment) are evenly distributed on the die head 25, and several external liquid-assisted liquid inlet bolts 18 (four in this embodiment) are evenly distributed on the extrusion die 12. The auxiliary fluid has a multi-directional flow channel, which makes the flow field in the mixing chamber more uniform and obtains a stable auxiliary film layer. The function can be realized as needed, and different functional auxiliary gases and liquids can be replaced.

[0041] Through holes are made in the flow channel reversing tube 5, the head body 25, and the melt diversion cone 24 to form a gas recovery channel 29. The exhaust bolt 30 is fastened to the flow channel reversing tube 5, and the gas recovery channel 29 is connected to an external gas recovery system to recover and reuse the auxiliary gas and nanoparticles on the inner wall of the microtube.

[0042] To ensure the temperature of the melt during extrusion molding, heating devices for heating the melt and temperature sensors for measuring the temperature of each component during extrusion are installed on each unit structure of the molding die. The heating devices include connecting pipe heating rings 2, duct reversing pipe heating rings 27, die head body heating rings 8, and extrusion die heating rings 19, which are respectively wrapped around the connecting pipe 4, duct reversing pipe 5, die head body 25, and extrusion die 12. The temperature sensors include connecting pipe temperature sensors 3, duct reversing pipe temperature sensors 28, die head body temperature sensors 23, and extrusion die temperature sensors 20, which are respectively embedded in the connecting pipe 4, duct reversing pipe 5, die head body 25, and extrusion die 16. The connecting pipe heating rings 2, duct reversing pipe heating rings 27, die head body heating rings 8, and extrusion die heating rings 19 are all symmetrical semi-ring structures, with the two halves of each heating ring fastened together by screws. Through holes are provided at the temperature sensor locations to facilitate the installation of the corresponding temperature sensors.

[0043] An antibacterial medical microtube is extruded using the gas-liquid co-assisted molding die of the present invention, as illustrated in the following example:

[0044] Step 1, Raw material processing: Use a constant temperature drying oven to dry the polymer elastomer and remove moisture;

[0045] Step 2, preparation of auxiliary fluid: Add antibacterial nanoparticles to the aerosol generator, and introduce gas at a certain flow rate and pressure to uniformly disperse antibacterial nanoparticles in the airflow. Introduce the gas into the inner gas auxiliary inlet bolt (9) through the auxiliary gas generation system. Mix the hydrophilic nanoparticles with the auxiliary liquid in the liquid mixing chamber, and introduce the liquid containing hydrophilic nanoparticles into the outer liquid auxiliary inlet bolt through the auxiliary liquid system.

[0046] Step 3: Start the extruder: After adding the extrusion material, turn on the power to the extruder and use the heating ring to heat each part of the extrusion die to the set temperature in stages, and use the temperature sensor to measure the temperature of each component in real time.

[0047] Step 4, Material Extrusion: The melt is highly smelted in the extruder to form a melt. Under the pushing action of the extrusion screw, the melt passes through the connecting pipe and the flow channel deflector, and the extrusion direction changes from horizontal to vertical. It then enters the die head body and enters the flow channel under the action of the melt diverting cone. Then, under the action of the guide mandrel and the extrusion die, a guide tube is formed in the extrusion die. The melt reaches the gas-liquid co-assisted area, where the internal auxiliary gas and external auxiliary liquid form a stable auxiliary layer on the inner and outer surfaces of the melt. Under the combined action of the shaping rod and the outer die, a guide tube that meets the functional and dimensional requirements is extruded.

[0048] Step 5: Cooling and Shaping Process: After the microtube is extruded from the die, it passes through a cooling system to obtain a shaped medical catheter with antibacterial function;

[0049] Step 6: By adjusting the pressure valves and flow valves of the gas-assisted system, gas recovery system, and liquid-assisted system, the flow rate and pressure of the auxiliary fluid are controlled to form a stable auxiliary film layer;

[0050] Step 7: Depending on the requirements for the preparation of medical catheters, different functional nanoparticles can be replaced, giving the catheters different functions. Furthermore, medical catheters with different size parameters can be prepared by replacing extrusion dies and flow guide mandrels with different structural parameters.

Claims

1. An antimicrobial medical catheter gas-liquid co-assist forming mold characterized by: The forming mold includes a connecting pipe (4), a flow channel deflector pipe (5), a die head body (25), an extrusion die (12), and an outer die (16) connected in sequence. The structural units of the forming mold are fixedly connected in pairs by fasteners, and an extrusion channel is formed inside the mold. The forming mold is equipped with a heating device for heating the melt and a temperature sensing device for measuring the temperature during the extrusion process. The extrusion channel is assembled from left to right with a melt diverting cone (24), a guide mandrel (10), and a shaping rod (15). The melt diverting cone (24) is installed in the internal channel of the die head (25), and the guide mandrel (10) is installed in the internal channel of the extrusion die (12). The guide mandrel (10) is fastened to the end of the melt diverting cone (24) by a threaded connector. The guide mandrel (10) has a cavity inside. One end of the shaping rod (15) passes through the cavity and is fixedly connected to the melt diverting cone (24) by a thread. The gap between the melt diverting cone (24), the guide mandrel (10), the die head (25), and the extrusion die (12) forms a melt flow channel. The gap between the melt splitter cone (24) and the guide core rod (10) forms an auxiliary gas mixing chamber (22) and a gas flow channel. The melt splitter cone (24) is fixed inside the head body (25) by several sets of internal gas auxiliary inlet bolts (9). The internal gas auxiliary inlet bolts (9) are connected to the external aerosol generator. A through-flow inlet channel is provided inside the internal gas auxiliary inlet bolts (9). An internal auxiliary gas flow channel is provided inside the melt splitter cone (24). The inlet channel is connected to the internal auxiliary gas flow channel. The gas flows into the auxiliary gas mixing chamber (22) and is finally fed into the aerosol generator to form a gas flow with uniformly dispersed antibacterial nanoparticles. The gas containing antibacterial nanoparticles enters the inner auxiliary gas flow channel in the melt split cone (24) through the air intake channel of the inner auxiliary gas intake bolt (9) and arrives at the auxiliary gas mixing chamber (22). When the melt is extruded through the gas flow channel, an air cushion film layer is formed on the inner surface, and the antibacterial nanoparticles are embedded in the surface and interior of the melt, so that the conduit has antibacterial function. The extrusion die (12) is provided with a powder metallurgy porous ring (13), which is fixed in the extrusion die (12) by an outer die (16) and fasteners; several sets of external liquid auxiliary inlet bolts (18) are inserted into the end of the extrusion die (12). The external liquid auxiliary inlet bolts (18) pass through the outer wall of the extrusion die (12) and communicate with its internal channel. The external liquid auxiliary inlet bolts (18), the extrusion die (12), the outer die (16), and the powder metallurgy porous ring (13) form an auxiliary liquid mixing chamber (17). The external liquid auxiliary inlet bolts (18) are provided with a through inlet channel. The auxiliary liquid containing hydrophilic nanoparticles enters the auxiliary liquid mixing chamber (17) through the inlet channel of the external liquid auxiliary inlet bolts (18). The auxiliary liquid is delivered to the outer surface of the melt through the permeation effect of the powder metallurgy porous ring (13) to form an auxiliary liquid layer and embed the nanoparticles into the interior of the melt surface. The connecting pipe (4) is perpendicular to the flow channel reversing pipe (5). The internal channels of the flow channel reversing pipe (5), the die head (25), the extrusion die (12) and the outer die (16) are on the same horizontal line, so that the melt can be extruded in the vertical direction. The overall mold adopts the right angle extrusion mode.

2. The gas-liquid co-assist forming mold for an antibacterial medical catheter according to claim 1, characterized in that: Through holes are made in the flow channel reversing pipe (5), the head body (25), and the melt diversion cone (24) to form a gas recovery channel (29). The exhaust bolt (30) is fastened to the flow channel reversing pipe (5) to connect the gas recovery channel (29) to an external gas recovery system for recovering auxiliary gas and nanoparticles.

3. The gas-liquid co-assist forming mold for an antibacterial medical catheter according to claim 1, characterized in that: Several sets of internal air-assisted air intake bolts (9) are evenly distributed around the head body (25), and several external liquid-assisted liquid intake bolts (18) are evenly distributed around the extrusion die (12).

4. The antimicrobial medical catheter gas-liquid co-assist forming mold according to claim 1, characterized in that: The heating device includes a connecting pipe heating ring (2), a flow channel reversing pipe heating ring (27), a die head body heating ring (8), and an extrusion die heating ring (19) respectively wrapped around the connecting pipe (4), the flow channel reversing pipe (5), the die head body (25), and the extrusion die (12). The temperature sensing device includes a connecting pipe temperature sensor (3), a flow channel reversing pipe temperature sensor (28), a die head body temperature sensor (23), and an extrusion die temperature sensor (20) respectively embedded in the connecting pipe (4), the flow channel reversing pipe (5), the die head body (25), and the extrusion die (12).

5. The antimicrobial medical catheter gas-liquid co-assist forming mold according to claim 4, characterized in that: The heating rings of the connecting pipe (2), the flow channel reversing pipe (27), the head body (8), and the extrusion die (19) are all symmetrical semi-ring structures, and the two halves of each heating ring are fastened together by screws; and through holes are provided at the temperature sensor position.

6. A gas-liquid co-molding method for an antibacterial medical microtube using the mold according to any one of claims 1 to 5 as a molding mold, characterized by, The method includes the following steps: Step 1: Raw material processing for extrusion: Use a constant temperature drying oven to dry the polymer elastomer and remove moisture; Step two, auxiliary fluid preparation: the antibacterial nanoparticles are added into the aerosol generator, and a certain flow pressure gas is introduced to uniformly disperse the antibacterial nanoparticles in the gas flow, and the gas is connected to the inner gas auxiliary inlet bolt (9); the hydrophilic nanoparticles are mixed with the auxiliary liquid, and the mixed liquid is introduced into the outer liquid auxiliary inlet bolt (18); Step three, start the extruder: after adding the extrusion raw material, turn on the power of the extruder, and turn on the heating device and temperature sensing device on the forming mold at the same time, use the heating device to heat each part to the set temperature in stages, and measure the temperature of each part in real time through the temperature sensing device; Step four, material extrusion: the extrusion raw material is melted at high temperature in the extruder to form a melt, which enters the forming mold under the pushing action of the extrusion screw. The melt changes the extrusion direction from horizontal to vertical after passing through the connecting pipe (4) and the flow channel change pipe (5), and enters the head body (25). Under the action of the melt flow cone (24), it enters the flow channel, and then under the action of the flow guide core rod body (10) and the extrusion die (12), it forms a guide pipe shape in the extrusion die. The melt reaches the gas-liquid auxiliary area; the gas containing antibacterial nanoparticles enters the inner auxiliary gas flow channel in the melt flow cone (24) through the gas inlet channel of the inner gas auxiliary inlet bolt (9), reaches the auxiliary gas mixing chamber (22), and forms a gas cushion film layer on the inner surface of the guide pipe during melt extrusion through the gas flow channel, and embeds the antibacterial nanoparticles into the guide pipe surface and the inside; the auxiliary liquid containing hydrophilic nanoparticles enters the auxiliary liquid mixing chamber (17) through the liquid inlet channel of the outer liquid auxiliary inlet bolt (18), and is sent to the outer surface of the melt through the permeation action of the powder metallurgy porous ring (13) to form an auxiliary liquid layer, and embeds the nanoparticles into the melt surface and the inside, then under the joint action of the shaping rod body (15) and the outer die (16), the guide pipe meeting the functional requirements and size requirements is extruded; Step five, cooling and shaping treatment: after the micro-tube extrusion die, the cooling system is used to obtain the shaped medical guide pipe with antibacterial function.

Images