Gastrointestinal integrated tube and preparation method thereof

Abstract

The invention belongs to the technical field of medical manufacturing, and particularly relates to a gastrointestinal integrated tube and a preparation method thereof. The tube body comprises a stomach tube section and an intestinal tube section, the stomach tube section is of a single-cavity structure, and the intestinal tube section is of a three-cavity structure. The preparation method comprises the following steps: (1) preparing raw materials: mixing the polyurethane base material with the antistatic agent and the antibacterial agent; (2) gradient extrusion molding: putting the functionalized polyurethane raw material into a double-screw extruder, and realizing the molding of an integrated pipe body by virtue of a multi-section hydraulic mold; (3) dynamic cavity number regulation and control: in the extrusion process, controlling a core mold switching system through a mechanical arm; and (4) post-treatment: performing water-cooling shaping and surface coating treatment on the pipe body of the integrated pipe. According to the core mold, the number of cavities is rapidly switched and adjusted, different clinical function requirements are met, the function expansibility and operation convenience are improved, the product size precision is high, the mechanical property is good, the product can bear external force and is durable, meanwhile, the good antistatic property, the good antibacterial property, the good lubricating property and the good biocompatibility are achieved, and the core mold is particularly suitable for fine treatment scenes such as the pediatric department.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical manufacturing, and particularly relates to a gastrointestinal integrated tube and a preparation method thereof. Background Art

[0002] In the field of medical devices, polyurethane gastrointestinal integrated tubes are widely used in gastrointestinal drainage, drug administration, and nutritional delivery as common devices in the treatment of gastrointestinal diseases and nutritional support. However, there are many problems to be solved urgently in the current traditional polyurethane gastrointestinal integrated tubes and their preparation methods.

[0003] The physiological structures of the human gastrointestinal tract vary significantly among individuals due to factors such as age, body type, and disease conditions. For example, the gastrointestinal tract of children is more slender than that of adults, requiring smaller and more precise diameters of gastrointestinal tubes. In actual use, if the diameter of a gastrointestinal integrated tube with a fixed diameter is too large, it is likely to cause damage to the gastrointestinal mucosa of the patient during insertion, increasing the patient's pain and possibly causing complications such as inflammation; if the diameter is too small, it cannot ensure sufficient drainage, drug administration, or nutritional delivery flow, seriously affecting the treatment effect. The diameters of existing polyurethane gastrointestinal integrated tubes are usually fixed and cannot meet the diverse needs of different patients.

[0004] Currently, the number of lumens of most gastrointestinal integrated tubes on the market is fixed. In actual medical procedures, multiple operations often need to be carried out simultaneously. For example, for certain gastrointestinal diseases, gastric juice drainage, drug perfusion, and nutritional substance delivery may need to be carried out simultaneously. A single-lumen tube obviously cannot achieve these functions simultaneously. Even for some multi-lumen tubes, the number of lumens is preset and unchangeable, and cannot be flexibly adjusted according to the actual situation during the treatment process. For example, in the intensive care unit, for patients with complex and changeable conditions, a single-lumen tube may be sufficient for simple drainage at the initial stage of treatment, but as the condition develops, more lumens may be needed to achieve multiple functions. Gastrointestinal integrated tubes with a fixed number of lumens cannot meet this dynamic change requirement, restricting their effectiveness and adaptability in clinical applications.

[0005] The traditional polyurethane gastrointestinal integrated tube preparation process mainly relies on fixed molds. Once the mold is determined, the diameter and number of cavities of the gastrointestinal tube produced are fixed. If products with different diameters or cavities are to be produced, the entire set of molds must be replaced, which not only greatly increases the production cost and prolongs the production cycle, but also makes it impossible to achieve changes in the diameter and number of cavities on the same tube body. Taking the extrusion molding process as an example, the polyurethane material is extruded through a fixed mold mouth to form a tube body. If the tube diameter is to be changed, it is necessary to replace the mold with a different caliber. Each mold change requires debugging and calibration, which consumes a lot of manpower, material resources and time. The method of changing the diameter of the gastrointestinal tube by secondary processing often damages the original structure of the tube body, resulting in uneven wall thickness of the tube body. For example, when the formed gastrointestinal tube is mechanically expanded or reduced, it is very easy to make the tube wall locally thinner or thicker, thereby affecting the strength and flexibility of the tube body. During use, such a tube body with uneven tube wall may have problems such as rupture or distortion, which reduces the reliability and safety of the product. Secondary processing is more difficult to change the number of cavities. It is difficult to accurately form multiple uniform, independent and well-functioning cavities on the tube body. It may also cause liquid cross-linking between cavities, causing liquids with different functions to interfere with each other, seriously affecting the normal use of the gastrointestinal tube.

[0006] In summary, the existing polyurethane gastrointestinal integrated tube and its preparation process have many drawbacks and cannot meet the increasingly complex and diverse clinical needs. The development of a new process preparation method that can achieve variable diameter and variable cavity number and ensure stable and reliable tube performance has important clinical significance and market demand. Summary of the invention

[0007] The purpose of the present invention is to provide a gastrointestinal integrated tube and a preparation method thereof.

[0008] In order to achieve the above object, the present invention provides the following technical solutions: A gastrointestinal integrated tube, with an outer diameter of 8mm for the gastric tube section, a single-lumen structure, and an outer diameter of 4mm for the intestinal tube section, a three-lumen structure, and the outer diameter of the tube body and the number of lumens transition through a gradient section whose length accounts for ≥60%; the wall thickness of the gradient section linearly decreases from 1.0mm±0.1mm to 0.5mm±0.1mm, and the wall thickness gradient change rate is ≤0.1mm / cm; the three lumens include a drainage cavity, a drug administration cavity and a nutrition cavity, and the cross-sectional area ratio of the three lumens is drainage cavity: drug administration cavity: nutrition cavity=1:(0.6-0.8):(1.2-1.5), and the wall thickness between lumens is 0.3mm±0.05mm; the dynamic friction coefficient of the tube surface is ≤0.1.

[0009] Furthermore, the surface of the pipe body of the tapered section is provided with a spiral micro-protrusion structure, the protrusion height is 50μm - 100μm, the spiral pitch is 1mm - 2mm, and the surface of the micro-protrusion is covered with a heparin-silicone oil composite coating, and the coating thickness is 10% - 15% of the protrusion height.

[0010] Furthermore, the spiral angle of the spiral micro-protrusion is 30° - 45°, and the spiral direction is consistent with the axial stretching direction of the pipe body of the integrated tube.

[0011] A preparation method of a gastrointestinal integrated tube includes the following steps: (1) Raw material preparation: Mix the polyurethane substrate with an antistatic agent and an antibacterial agent; wherein the antistatic agent accounts for 0.5% - 3% of the total weight of the functionalized polyurethane raw materials, and the antibacterial agent accounts for 1% - 3% of the total weight of the functionalized polyurethane raw materials; mix at a stirring speed of 1200rpm - 1800rpm for not less than 30 minutes at a temperature of 25℃ - 40℃ to obtain the functionalized polyurethane raw materials; (2) Gradient extrusion molding: Put the functionalized polyurethane raw materials obtained in step (1) into a twin-screw extruder, and use a multi-stage hydraulic die to form the pipe body of the integrated tube. The multi-stage hydraulic die adjusts the inner diameter in real time so that the diameter of the pipe body of the integrated tube can gradually change continuously from 8mm to 4mm, and a transition section with a taper angle in the range of 15° - 30° is provided between adjacent hydraulic die sections, and the length of the transition section is 1.5 times - 3 times the change in the diameter of the pipe body of the integrated tube; (3) Dynamic cavity number regulation: During the extrusion process, through the manipulator to control the mandrel switching system, it is possible to complete the switching operation of the single-cavity, double-cavity, triple-cavity or quadruple-cavity mandrel according to the change in the diameter of the pipe body of the integrated tube within 0.5 seconds, and the cavity spacing tolerance ≤ 0.1mm after the switching is completed; (4) Post-treatment: Carry out water cooling and shaping and surface coating treatment on the pipe body of the integrated tube. During the water cooling process, the temperature is gradually decreased from 25℃ to 10℃ at a rate of 2℃ / min, and the heparin-silicone oil composite layer is applied to the surface coating by plasma spraying technology, the spraying pressure is 0.2MPa - 0.5MPa, and the coating thickness is 5μm - 15μm.

[0012] Furthermore, the antistatic agent in step (1) is a quaternary ammonium salt compound, and the antibacterial agent is silver ion nanoparticles coated with polyethylene glycol, and the particle size is 20nm - 50nm.

[0013] Furthermore, the rule of the mandrel switching system in step (3) is: when the diameter of the pipe body of the integrated tube ≥ 6mm, it is switched to a single cavity; when the diameter of the pipe body of the integrated tube is 4mm - 6mm, it is switched to a double cavity or a triple cavity; when the diameter of the pipe body of the integrated tube ≤ 4mm, it is switched to a triple cavity or a quadruple cavity; the cross-section of the cavity is quasi-elliptical, and the ratio of the major axis to the minor axis is 1.2:1 - 1.5:1.

[0014] Further, during the water-cooling shaping process described in step (4), the circulating flow rate of the cooling water is 10 L / min - 15 L / min, and the ratio of the axial stretching rate to the cooling rate of the integrated tube body is 1: (0.8 - 1.2). When the ratio is 1:1, the axial shrinkage rate of the tube body ≤ 2%.

[0015] Further, the gradual change rate of the cavity number switching is 0.8 cavity / mm - 1.2 cavity / mm, and it is synchronized with the change rate of the diameter of the integrated tube body.

[0016] The beneficial effects of the present invention are as follows: (1) Improvement of material properties: By adding specific antistatic agents and antibacterial agents to the polyurethane substrate and optimizing the mixing conditions, the tube body is endowed with stable antistatic and high-efficiency antibacterial properties, enhancing the hygienic safety and durability.

[0017] (2) Strong structural adaptability: The multi-stage hydraulic die realizes a smooth gradual change in the pipe diameter, avoiding structural defects and better adapting to the physiological structure of the gastrointestinal tract; the core die quickly switches to adjust the cavity number, precisely meeting different clinical functional requirements and improving the functional expandability and operation convenience.

[0018] (3) Good post-treatment effect: The gradient water-cooling shaping eliminates internal stress, improving the physical properties and dimensional stability; the heparin-silicone oil composite coating is plasma-sprayed, enhancing the lubricity and biocompatibility, reducing the insertion injury and rejection reaction.

[0019] (4) Excellent product performance: The product has high dimensional accuracy and good mechanical properties, can withstand external forces and is durable. At the same time, it has good antistatic, antibacterial, lubricating and biocompatible properties, and is especially suitable for refined treatment scenarios such as pediatrics, providing high-quality treatment solutions. Description of the Drawings

[0020] Figure 1 A schematic structural diagram of a gastrointestinal integrated tube. Detailed Embodiments

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention; obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the protection scope of the present invention. Embodiment 1

[0022] (I) Raw material preparation 1. Select a polyurethane substrate as the base material. The antistatic agent is cetyltrimethylammonium bromide, accounting for 3% of the total weight of the functionalized polyurethane raw materials. The antibacterial agent is silver ion nanoparticles coated with polyethylene glycol, with a particle size of 30 nm, accounting for 2% of the total weight of the functionalized polyurethane raw materials.

[0023] 2. Place the polyurethane substrate, antistatic agent, and antibacterial agent in a stirring device and mix them at a stirring speed of 1500 rpm for 40 minutes at a temperature of 30 °C to obtain the functionalized polyurethane raw materials, ensuring that each component is evenly dispersed.

[0024] (II) Gradient extrusion molding 1. Put the obtained functionalized polyurethane raw materials into a twin-screw extruder. Use a multi-stage hydraulic die to form the body of the integrated tube. The multi-stage hydraulic die adjusts the inner diameter in real time, so that the diameter of the integrated tube body gradually changes continuously from 8 mm to 4 mm.

[0025] 2. Set a transition section with a cone angle of 25° between adjacent hydraulic die sections, and the length of the transition section is 8 mm.

[0026] (III) Dynamic cavity number regulation 1. During the extrusion process, control the mandrel switching system through a robotic arm. The rules of the mandrel switching system are as follows: when the diameter of the integrated tube body ≥ 6 mm, switch to a single cavity; when the tube body diameter is between 4 mm - 6 mm, switch to a three-cavity; the gradual change rate of the cavity number is 1.0 cavity / mm, and it is synchronized with the change rate of the integrated tube body diameter, and the mandrel switching operation can be completed within 0.5 seconds. After the switching is completed, the cavity spacing tolerance is 0.08 mm.

[0027] 2. The cross-section of the cavity is quasi-elliptical, and the ratio of the major axis to the minor axis is 1.3:1.

[0028] (IV) Post-treatment 1. Carry out water cooling and shaping on the integrated tube body. During the water cooling process, cool down from 25 °C to 10 °C at a rate of 2 °C / min. The set water circulation flow rate of the cooling water is 12 L / min, and the ratio of the axial stretching rate of the integrated tube body to the cooling rate is 1:1. Under these conditions, the axial shrinkage rate of the tube body is 1.8%.

[0029] 2. Surface coating treatment: The surface coating is applied with a heparin-silicone oil composite layer by plasma spraying technology. The spraying pressure is 0.3 MPa, and the coating thickness is 12 μm. The surface of the tube body in the transition section is provided with a spiral micro-protrusion structure. The protrusion height is 80 μm, the spiral pitch is 1.5 mm, and the surface of the micro-protrusion is covered with a heparin-silicone oil composite coating, and the coating thickness is 15% of the protrusion height. The spiral angle of the spiral micro-protrusion is 40°, and the spiral direction is consistent with the axial stretching direction of the integrated tube body.

[0030] (V) Performance indicators 1. Coefficient of kinetic friction: Measured by the ASTM D1894 standard test method, the coefficient of kinetic friction is 0.08, indicating that the surface of the tube body is extremely smooth and has little friction on tissues when moving in the body.

[0031] 2. Antibacterial rate: Using the standard antibacterial test method, the antibacterial rate against Escherichia coli reaches 99.3% in 24 hours, effectively inhibiting bacterial growth and reducing the risk of infection.

[0032] 3. Tensile strength: Measured by a material tensile testing machine, the tensile strength of the tapered section is 28 MPa, indicating that the tube body has high strength at the diameter-changing part and is not easily broken.

[0033] 4. Drainage flow rate: Simulating the clinical drainage scenario, the drainage flow rate of the intestinal tube section is measured to be 82 mL / min, which can meet the normal drainage requirements.

[0034] 5. Cavity spacing tolerance: Detected by a high-precision measuring instrument, the cavity spacing tolerance is 0.08 mm, ensuring the position accuracy between cavities and facilitating the normal realization of various functions. Example 2

[0035] (I) Raw material preparation 1. The antistatic agent is selected as dodecyl dimethyl benzyl ammonium chloride, accounting for 0.5% of the total weight of the functionalized polyurethane raw materials. The antibacterial agent is still silver ion nanoparticles coated with polyethylene glycol, with a particle size of 30 nm and a proportion of 2%.

[0036] 2. Mix at a stirring speed of 1200 rpm for 30 minutes at 25°C to obtain the functionalized polyurethane raw materials.

[0037] (II) Gradient extrusion molding 1. A multi-stage hydraulic mold makes the diameter of the integrated tube body gradually change from 8 mm to 4 mm continuously.

[0038] 2. The cone angle of the transition section between adjacent hydraulic mold sections is 15°, and the length of the transition section is 12 mm.

[0039] (III) Dynamic cavity number regulation 1. The rules of the core mold switching system are the same as those in Example 1. The gradual change rate of cavity number switching is 0.8 cavity / mm, synchronized with the tube body diameter change rate, and the switching is completed within 0.5 seconds. The cavity spacing tolerance ≤ 0.1 mm.

[0040] 2. The cross-section of the cavity is quasi-elliptical, and the ratio of the major axis to the minor axis is 1.2:1.

[0041] (IV) Post-treatment 1. Water cooling and shaping: Cool from 25°C to 10°C at a rate of 2°C / min, with a cooling water circulation flow rate of 10 L / min. The ratio of the axial stretching rate to the cooling rate of the integrated tube body is 1:0.8, and the axial shrinkage rate of the tube body is 2.1%.

[0042] 2. Surface coating treatment: Plasma spray a heparin-silicone oil composite layer with a spraying pressure of 0.2 MPa and a coating thickness of 5 μm. On the surface of the tube body in the transition section, there is a spiral micro-protrusion structure with a protrusion height of 50 μm, a spiral pitch of 1 mm, the surface coating thickness of the micro-protrusion is 10% of the protrusion height, and the spiral angle is 30°, with the spiral direction being the same as the axial stretching direction.

[0043] (V) Performance indicators 1. Coefficient of kinetic friction: 0.09, and the surface still maintains good lubricity.

[0044] 2. Antibacterial rate: 98.5%, with good antibacterial performance.

[0045] 3. Tensile strength: 25 MPa, meeting the strength requirements of the tube body.

[0046] 4. Drainage flow rate: 78 mL / min, which can meet the basic drainage function.

[0047] Comparative Example 1 (I) Raw material preparation 1. The antistatic agent selects tetrabutylammonium bromide among quaternary ammonium salt compounds, accounting for 4% of the total weight of the functionalized polyurethane raw materials, and no antibacterial agent is added.

[0048] 2. Mix at a stirring speed of 1800 rpm at 40°C for 30 minutes.

[0049] (II) Gradient extrusion molding Same as Example 1, a multi-stage hydraulic mold is used to continuously vary the diameter of the integrated tube body from 8 mm to 4 mm, and the transition cone angle between adjacent hydraulic mold segments is 25°, with a length of 8 mm.

[0050] (III) Dynamic cavity number regulation Same as Example 1, the core mold switching system is regular, the cavity number switching gradual speed is 1.0 cavity / mm, and the switching is completed within 0.5 seconds. The cavity spacing tolerance is 0.08 mm, and the cross-section of the cavity is approximately elliptical, with the ratio of the major axis to the minor axis being 1.3:1.

[0051] (IV) Post-treatment Same as Example 1, water cooling and shaping: Cool from 25°C to 10°C at a rate of 2°C / min, with a cooling water circulation flow rate of 12 L / min. The ratio of the axial stretching rate to the cooling rate of the integrated tube body is 1:1, and the surface coating treatment parameters are the same.

[0052] (V) Performance indicators 1. Coefficient of kinetic friction: 0.15. Due to the antistatic agent exceeding the scope, electrostatic adsorption of particles occurs, resulting in an increase in the friction coefficient.

[0053] 2. Antibacterial rate: 72.0%. Due to the absence of an antibacterial agent, the antibacterial performance has decreased significantly.

[0054] 3. Tensile strength: 22 MPa, which is lower than that of Example 1.

[0055] 4. Drainage flow rate: 50 mL / min. The drainage function is affected.

[0056] Comparative Example 2 (I) Raw material preparation Same as Example 1. Cetyltrimethylammonium bromide as the antistatic agent accounts for 3%, and silver ion nanoparticles coated with polyethylene glycol (particle size 30 nm) as the antibacterial agent account for 2%. Mix at a stirring speed of 1500 rpm at 30 °C for 40 minutes.

[0057] (II) Gradient extrusion molding 1. The multi-stage hydraulic die makes the diameter of the integrated pipe body gradually change from 8 mm to 4 mm continuously.

[0058] 2. The taper angle of the transition section between adjacent hydraulic die segments is 40°, and the length is 4 mm.

[0059] (III) Dynamic cavity number regulation The cavity number is not switched synchronously, and it is a single cavity throughout the process.

[0060] (IV) Post-treatment Same as Example 1. The water cooling setting and surface coating treatment parameters are the same.

[0061] (V) Performance indicators 1. Coefficient of kinetic friction: 0.12, slightly higher than that of Example 1.

[0062] 2. Antibacterial rate: 97.0%. The antibacterial performance is less affected.

[0063] 3. Tensile strength: 18 MPa. Due to the too large taper angle of the transition section, cracks appear and the strength decreases.

[0064] 4. Drainage flow rate: 45 mL / min. The drainage efficiency is low.

[0065] For the comparison of each performance index between the examples and the comparative examples, see Table 1.

[0066] Table 1

[0067] The above are only the preferred specific embodiments of the present invention; however, the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, making equivalent substitutions or changes according to the technical solution of the present invention and its improved conceptions, shall be covered by the protection scope of the present invention.

Claims

1. A gastrointestinal integrated tube, characterized in that: The integrated tube body includes a gastric tube section and an intestinal tube section. The gastric tube section has an outer diameter of 8mm and a single-cavity structure. The intestinal tube section has an outer diameter of 4mm and a three-cavity structure. The outer diameter of the tube body and the number of cavities are transitioned through a gradient section whose length accounts for ≥60%; the wall thickness of the gradient section decreases linearly from 1.0mm±0.1mm to 0.5mm±0.1mm, and the wall thickness gradient change rate is ≤0.1mm / cm; the three cavities include a drainage cavity, a drug administration cavity and a nutrition cavity, and the cross-sectional area ratio of the three cavities is drainage cavity: drug administration cavity: nutrition cavity = 1:(0.6-0.8):(1.2-1.5), and the wall thickness between cavities is 0.3mm±0.05mm; the dynamic friction coefficient of the tube body surface is ≤0.

1.

2. The gastrointestinal integrated tube according to claim 1, characterized in that: The tube body surface of the gradient section is provided with a spiral micro-protrusion structure, the protrusion height is 50μm-100μm, the spiral pitch is 1mm-2mm, and the micro-protrusion surface is covered with a heparin-silicone oil composite coating, and the coating thickness is 10%-15% of the protrusion height.

3. The gastrointestinal integrated tube according to claim 2, characterized in that: The helical angle of the spiral micro-protrusion is 30°-45°, and the helical direction is consistent with the axial stretching direction of the integrated tube body.

4. A method for preparing a gastrointestinal integrated tube, characterized in that: The following steps are involved: (1) Raw material preparation: a polyurethane substrate is mixed with an antistatic agent and an antibacterial agent; wherein the antistatic agent accounts for 0.5%-3% of the total weight of the functionalized polyurethane raw material, and the antibacterial agent accounts for 1%-3% of the total weight of the functionalized polyurethane raw material; the mixture is mixed at a stirring speed of 1200 rpm-1800 rpm and a temperature of 25°C-40°C for not less than 30 minutes to obtain a functionalized polyurethane raw material; (2) Gradient extrusion molding: the functionalized polyurethane raw material obtained in step (1) is fed into a twin-screw extruder, and the one-piece tube body is molded by means of a multi-section hydraulic mold, wherein the multi-section hydraulic mold adjusts the inner diameter in real time so that the diameter of the one-piece tube body can be continuously and gradually changed from 8 mm to 4 mm, and a transition section with a taper angle in the range of 15°-30° is provided between adjacent hydraulic mold sections, and the length of the transition section is 1.5 to 3 times the change in the diameter of the one-piece tube body; (3) Dynamic cavity number control: During the extrusion process, the mandrel switching system is controlled by a robotic arm, which can complete the switching operation of the single-cavity, double-cavity, triple-cavity or quad-cavity mandrel according to the change of the diameter of the integrated tube body within 0.5 seconds. After the switching is completed, the cavity spacing tolerance is ≤0.1mm; (4) Post-treatment: The integrated tube body is subjected to water cooling and surface coating treatment. The water cooling process is gradually cooled from 25°C to 10°C at a rate of 2°C / min. The surface coating is applied with a heparin-silicone oil composite layer using plasma spraying technology. The spraying pressure is 0.2MPa-0.5MPa, and the coating thickness is 5μm-15μm.

5. The method for preparing the gastrointestinal integrated tube according to claim 4, characterized in that: The antistatic agent in step (1) is a quaternary ammonium salt compound, and the antibacterial agent is polyethylene glycol-coated silver ion nanoparticles with a particle size of 20nm-50nm.

6. The method for preparing the gastrointestinal integrated tube according to claim 4, characterized in that: The core mold switching system rules of step (3) are as follows: when the diameter of the one-piece tube body is ≥6mm, it is switched to a single cavity; when the diameter of the one-piece tube body is 4mm-6mm, it is switched to a double cavity or a triple cavity; when the diameter of the one-piece tube body is ≤4mm, it is switched to a triple cavity or a quadruple cavity; the cross section of the cavity is elliptical, and the ratio of the major axis to the minor axis is 1.2:1-1.5:

1.

7. The method for preparing the gastrointestinal integrated tube according to claim 4, characterized in that: During the water cooling and shaping process in step (4), the cooling water circulation flow rate is 10L / min-15L / min, and the ratio of the axial stretching rate of the one-piece tube body to the cooling rate is 1:(0.8-1.2), and when the ratio is 1:1, the axial shrinkage rate of the tube body is ≤2%.

8. The method for preparing the gastrointestinal integrated tube according to claim 6, characterized in that: The gradual rate of switching the number of cavities is 0.8 cavities / mm-1.2 cavities / mm, and is synchronized with the change rate of the diameter of the integrated tube body.

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