Preparation method of low-permeability braided artificial blood vessels

Abstract

This invention provides a method for preparing low-permeability woven artificial blood vessels. The method involves twisting polyester filaments with absorbent fibers to form a composite fiber, then coating its surface with a collagen solution and drying it. The composite fiber is used as the weft yarn, and the warp and weft yarns are interwoven through a weaving process to form the artificial blood vessel. The prepared artificial blood vessel is then immersed in deionized water, followed by post-treatments such as pressure application, shaping, and drying. After absorbing water, the weft yarn expands; after pressure treatment, the weft yarn is compressed and deformed into a flat shape to fill the fabric gaps; simultaneously, during water absorption, the collagen solution generates viscosity, causing the warp and weft yarns to adhere tightly upon contact. This physical processing improves the water absorption of the artificial blood vessel, reduces its blood permeability, and effectively solves the problems of high permeability and bleeding caused by loose fabric structure in existing textile-based artificial blood vessels.

Description

Technical Field

[0001] This invention relates to the field of textile biomaterials technology, and in particular to a method for preparing low-permeability woven artificial blood vessels. Background Technology

[0002] Currently, treatments for vascular diseases mainly include implantation of tissue-engineered vascular grafts, stent placement, surgical bypass surgery, angioplasty, and implantation of non-biodegradable catheters. However, currently fabricated artificial blood vessels suffer from insufficient biocompatibility, high bleeding rates, and high manufacturing costs, making the development of artificial blood vessels with practical application value essential. To address these issues, research on various types of artificial blood vessels is ongoing, with textile-based artificial blood vessels showing promising results in both research and practical applications.

[0003] In the prior art, patent application number 202020169010.9, published on September 29, 2020, entitled "A Composite Artificial Blood Vessel," discloses a method for preparing a composite artificial blood vessel. This method involves using electrospinning to place a first nanofiber layer of collagen and lactocaprolactone copolymer as the inner layer, and then casting a second nanofiber layer of lactocaprolactone into the outer layer using a mold to prepare the artificial blood vessel. However, the artificial blood vessel prepared by electrospinning requires high-voltage electrostatics, resulting in low production efficiency. Furthermore, both the inner and outer layers of the double-layered tubular artificial blood vessel have microporous structures, which can easily cause bleeding and are not conducive to clinical application.

[0004] Additionally, application number 202111404414.7, published on March 11, 2022, entitled "A Coating Method for Braided Artificial Blood Vessels and the Artificial Blood Vessel," describes a method where a braided preform is first degreased, then coated to obtain a coated braided preform; a texture is then created on the coated preform, followed by another coating treatment to finally obtain a coated artificial blood vessel. While this method can produce artificial blood vessels that meet usage requirements, its manufacturing process is complex and inefficient. Furthermore, the multi-layer coating process cannot guarantee that the pores of the artificial blood vessel are suitable for cell growth, thus making it unsuitable for large-scale use.

[0005] In view of this, it is necessary to design a method for preparing low-permeability braided artificial blood vessels to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing low-permeability braided artificial blood vessels.

[0007] To achieve the above-mentioned objectives, this invention provides a method for preparing a low-permeability braided artificial blood vessel, comprising the following steps:

[0008] S1. After arranging the absorbent fibers in parallel on both sides of the polyester filament, the fibers are twisted. The mass ratio of the polyester filament to the absorbent fibers is (1:0.1)-(1:0.5), the twist direction is Z twist or S twist, and the twist degree is 100-500 twists / m, thus obtaining the composite fiber.

[0009] S2. Add collagen to distilled water and stir at 200-800 r / min at 20-60℃ for 18-24 hours. Let it stand for 10 hours to remove bubbles, and a uniform collagen solution will be obtained.

[0010] S3. After immersing the composite fiber obtained in step S1 into the collagen solution, remove it and uniformly coat the surface of the composite fiber with the collagen solution. Then, dry the composite fiber at 80°C for 1-3 hours to form a coating on the surface of the composite fiber. The thickness of the coating is 0.1-10 μm and the content of the coating is 1-10% of the weight of the composite fiber.

[0011] S4. The composite fiber obtained in step S1 is used as weft yarn and woven in a dry environment. The weaving equipment used in this process is a shuttle loom, the warp yarn is polyester, the warp yarn is hooked with a reed hook and pulled out from the reed eye, and then the warp yarn is introduced into the reed teeth with a reed inserter. The warp yarn and the weft yarn are woven together to form a tubular fabric, and the woven artificial blood vessel can be obtained.

[0012] S5. The braided artificial blood vessel obtained in step S4 is subjected to post-processing. The post-processing steps are as follows: first, the braided artificial blood vessel is soaked in distilled water for 5-10 minutes to allow the composite fibers to expand; then, a pressure of 0.5-1 MPa is applied to both sides of the wall of the braided artificial blood vessel for 10-60 seconds; next, it is heated and shaped at 100-120°C for 20-60 minutes; finally, it is dried at 80°C for 1-3 hours to obtain the low-permeability braided artificial blood vessel.

[0013] Preferably, in step S1, the absorbent fiber is one of alginate fiber, cellulose-based superabsorbent fiber, or polyvinyl alcohol-based superabsorbent fiber.

[0014] Preferably, in step S1, the composite fiber has a diameter of 60-200D and a number of filaments of 20-150.

[0015] Preferably, in step S2, the collagen is one of fish collagen, porcine collagen, or bovine collagen, the molecular weight of the collagen is 10,000 to 100,000, and the mass fraction of the collagen protein solution is 5% to 20%.

[0016] Preferably, in step S4, the polyester warp yarn in the woven artificial blood vessel has a thickness of 60-300D and a number of 20-100 filaments.

[0017] Preferably, in step S4, the fabric weave structure of the artificial blood vessel is one of plain weave, twill weave, or satin weave.

[0018] Preferably, in step S4, the warp density of the braided artificial blood vessel is 100-600 threads / 5cm, and the weft density of the braided artificial blood vessel is 100-600 threads / 5cm.

[0019] Preferably, in step S4, the inner diameter of the braided artificial blood vessel is 6-40 mm, and the wall thickness of the braided artificial blood vessel is 0.5-2 mm.

[0020] The beneficial effects of this invention are:

[0021] 1. The method for preparing low-permeability woven artificial blood vessels provided by this invention involves twisting polyester filaments and absorbent fibers into composite fibers, then forming a collagen solution coating on the surface and drying it. The composite fibers are used as weft yarns, and the warp and weft yarns are interwoven through a weaving process to form the artificial blood vessel. The prepared artificial blood vessel is immersed in deionized water, followed by post-treatments such as pressure application, shaping, and drying. After absorbing water, the weft yarns expand; after pressure treatment, the weft yarns are compressed and deformed into a flat shape to fill the gaps; simultaneously, during the water absorption process, the collagen solution generates viscosity, making the warp and weft yarns adhere more firmly after contact. Through physical processing, the water absorption of the artificial blood vessel is improved, and the blood permeability of the artificial blood vessel is reduced, effectively solving the problems of high permeability and bleeding caused by the loose structure of the vascular fabric in existing textile-type artificial blood vessels. In the above process, artificial blood vessels that are suitable for cell growth and adhesion, have good elasticity, have a tight tissue structure, and have anticoagulant and anti-bleeding effects can also be prepared by adjusting parameters such as the thickness of the composite fiber, the concentration of the coating, the inner diameter of the artificial blood vessel, and the thickness of the blood vessel wall.

[0022] 2. The method for preparing low-permeability woven artificial blood vessels provided by the present invention, by combining polyester with fibers that have water absorption and swelling properties as weft yarns, can endow the artificial blood vessels with water absorption properties, thereby timely absorbing the blood that seeps out of the blood vessels when bleeding occurs; at the same time, collagen has good bioactivity, and coating the surface of the composite fiber with collagen solution is beneficial to improving its biocompatibility, promoting cell migration, proliferation and differentiation on blood vessels, and after the post-processing process, the coating is evenly embedded in the fabric gaps, making the warp and weft yarns more tightly bonded, enhancing the internal fabric structure of the artificial blood vessels, which is beneficial to the further processing of the artificial blood vessels. Attached Figure Description

[0023] Figure 1A schematic diagram illustrating the preparation process of the low-permeability braided artificial blood vessel provided by the present invention;

[0024] Figure 2 A cross-sectional schematic diagram of the low-permeability braided artificial blood vessel provided by the present invention;

[0025] Figure 3 A schematic diagram of the low-permeability braided artificial blood vessel structure provided by the present invention;

[0026] The attached figures are labeled as follows:

[0027] 1. Warp yarn; 2. Weft yarn. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0030] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0031] Please see Figures 1 to 3 As shown, the present invention proposes a method for preparing a low-permeability braided artificial blood vessel, which includes the following steps:

[0032] S1. Preparation of composite fibers:

[0033] After the absorbent fibers are arranged in parallel on both sides of the polyester filament, they are twisted. The mass ratio of the polyester filament to the absorbent fibers is (1:0.1)-(1:0.5). The two fibers are twisted in the direction of Z twist or S twist, and the twist is 100-500 twists / m, thus obtaining the composite fiber.

[0034] S2. Preparation of collagen solution:

[0035] Add collagen to distilled water and stir at 200-800 r / min at 20-60℃ for 18-24 h. Let it stand for 10 h to remove bubbles, and you will get a homogeneous collagen solution.

[0036] S3, Composite Fiber Coating Treatment:

[0037] After immersing the composite fiber in a collagen solution, remove it and uniformly coat the surface of the composite fiber with the collagen solution. The coating thickness is 0.1-10 μm, and the coating content is 1-10% of the weight of the composite fiber. After completing the above steps, dry the composite fiber at 80°C for 1-3 hours.

[0038] S4. Preparation of braided artificial blood vessels:

[0039] The composite fiber obtained in step S1 is used as weft yarn 2 and woven in a dry environment. The weaving equipment used in this process is a shuttle loom, and the warp yarn 1 is polyester. The warp yarn 1 is hooked with a reed hook and pulled out from the reed eye. Then, the warp yarn 1 is introduced into the reed teeth with a reed inserter. The warp yarn 1 and the weft yarn 2 are woven together to form a tubular fabric, and the woven artificial blood vessel can be obtained.

[0040] S5. Preparation of low-permeability braided artificial blood vessels:

[0041] The braided artificial blood vessel obtained in step S4 is then subjected to post-processing. The post-processing steps are as follows: first, the braided artificial blood vessel is soaked in distilled water for 5-10 minutes to allow the composite fibers to expand; then, a pressure of 0.5-1 MPa is applied to both sides of the wall of the braided artificial blood vessel for 10-60 seconds; next, it is heated and shaped at 100-120℃ for 20-60 minutes; finally, it is dried at 80℃ for 1-3 hours to obtain the low-permeability braided artificial blood vessel.

[0042] Preferably, in step S2, the collagen source is one of fish collagen, porcine collagen, or bovine collagen, with a collagen molecular weight of 10,000 to 100,000 and a collagen protein solution mass fraction of 5-20%, which improves the wetting and adhesive properties of the weft yarn 2, thereby enhancing the bonding force between the warp yarn 1 and the weft yarn 2 in the fabric.

[0043] Preferably, in step S1, the absorbent fiber is one of alginate fiber, cellulose-based superabsorbent fiber, or polyvinyl alcohol-based superabsorbent fiber, with a composite fiber thickness of 60-200D and 20-150 filaments. Alginate fiber can absorb water rapidly and its water absorption ratio is adjustable, with a maximum water absorption ratio of up to 100 times its own weight; cellulose-based superabsorbent fiber contains a large number of hydroxyl groups, resulting in strong water absorption and a fast absorption rate; polyvinyl alcohol-based superabsorbent fiber is obtained by grafting and modifying hydrophilic polyvinyl alcohol containing multiple hydroxyl groups to obtain a fiber with a high water absorption ratio; using polyester and superabsorbent fiber composite as weft yarn 2 improves the problem of poor water absorption in artificial blood vessel fabrics and enhances the anti-bleeding ability of artificial blood vessels. Furthermore, all three types of fibers are biodegradable materials.

[0044] Preferably, in step S4, the material of the warp yarn 1 in the artificial blood vessel is polyester; the polyester of the warp yarn 1 in the artificial blood vessel has a thickness of 60-300D, a single filament count of 20-100, and the fabric structure of the artificial blood vessel is one of plain weave, twill weave, or satin weave.

[0045] Preferably, in step S4, the warp density of the artificial blood vessel is 100-600 threads / 5cm, and the weft density is 100-600 threads / 5cm. When the warp and weft densities of the artificial blood vessel meet the above conditions, it can ensure that the fabric structure of the artificial blood vessel is tight while having the flexibility of the fabric, which is conducive to the growth and adhesion of cells in the blood vessel. If the warp and weft densities are less than 100 threads / 5cm, the fabric structure is not tight enough, which can easily lead to the wall of the artificial blood vessel being not tight enough, and can easily cause bleeding. If the warp and weft densities are greater than 600 threads / 5cm, the fabric structure is too tight, which can lead to the wall of the artificial blood vessel being too stiff and lacking flexibility, and is also not conducive to the growth and adhesion of vascular endothelial cells.

[0046] Preferably, in step S4, the inner diameter of the artificial blood vessel is 6-40 mm and the wall thickness is 0.5-2 mm. An artificial blood vessel with an inner diameter that meets the above conditions can ensure that the blood vessel has good compliance, and an artificial blood vessel with a wall thickness of 0.5-2 mm can ensure that the blood vessel has excellent elasticity and resistance to deformation.

[0047] The following specific embodiments further illustrate the preparation method of a low-permeability braided artificial blood vessel according to the present invention:

[0048] Example 1

[0049] This embodiment describes a method for preparing low-permeability braided artificial blood vessels, comprising the following steps:

[0050] S1. Preparation of composite fibers:

[0051] The absorbent fibers are arranged in parallel on both sides of the polyester filament and then twisted. The mass ratio of the polyester filament to the absorbent fibers is 1:0.1. The two fibers are twisted in a Z-twist direction with a twist of 300 twists / m to obtain the composite fiber.

[0052] S2. Preparation of collagen solution:

[0053] Collagen was added to distilled water and stirred at 500 r / min at 60°C for 10 h. After standing for 10 h to remove bubbles, a homogeneous collagen solution was obtained.

[0054] S3, Composite Fiber Coating Treatment:

[0055] After immersing the composite fiber in a collagen solution, remove it and uniformly coat the surface of the composite fiber with the collagen solution. The coating thickness is 1 μm and the coating content is 1% of the weight of the composite fiber. After completing the above steps, dry the composite fiber at 80°C for 1 hour.

[0056] S4. Preparation of braided artificial blood vessels:

[0057] The composite fiber obtained in step S1 is used as weft yarn 2 and woven in a dry environment. The weaving equipment used in this process is a shuttle loom, and the warp yarn 1 is polyester. The warp yarn 1 is hooked with a reed hook and pulled out from the reed eye. Then, the warp yarn 1 is introduced into the reed teeth with a reed inserter. The warp yarn 1 and the weft yarn 2 are woven together to form a tubular fabric, and the woven artificial blood vessel can be obtained.

[0058] S5. Preparation of low-permeability braided artificial blood vessels:

[0059] The braided artificial blood vessel obtained in step S4 is then subjected to post-processing. The post-processing steps are as follows: the woven artificial blood vessel is immersed in distilled water for 5 minutes to allow the composite fibers to expand; then, a pressure of 0.5 MPa is applied to both sides of the wall of the braided artificial blood vessel for 10 seconds; next, it is heated at 100°C for 60 minutes to set its shape; finally, the braided artificial blood vessel is dried at 80°C for 1-3 hours to obtain a low-permeability braided artificial blood vessel.

[0060] A schematic diagram of the artificial blood vessel structure obtained in this embodiment is shown below. Figure 3 As shown, the permeability of the prepared artificial blood vessel was tested according to ISO 7198:1998: Before testing, the blood vessel was soaked in deionized water. One end of the sample was connected to a water injection pump and secured with a rope to ensure the blood vessel was wrinkle-free. The other end of the blood vessel was folded and clamped to ensure that water passing through the artificial blood vessel would not leak out from the interface. Water was slowly injected into the artificial blood vessel using the water injection pump, ensuring the pressure gauge remained stable within the range of 16.0±0.3 kPa (120±2 mmHg). The amount of water leaking through the sample surface within 60±1 s was collected and measured. The prepared artificial blood vessel had a water permeability of 13.7 mL·cm³ at 16 kPa. -2 ·min -1 .

[0061] Examples 2 to 5

[0062] The only difference between Examples 2 to 5 and Example 1 is that the concentration of the coating solution is different in step S2. The other steps are basically the same as in Example 1 and will not be repeated here. The concentration settings of the coating solution in Examples 1 to 5 are shown in Table 1. Artificial blood vessels prepared from composite fibers coated with collagen solutions containing mass fractions of 15%, 10%, 12%, 18%, and 20% were all collected and measured within 60±1 seconds under a pressure range of 16.0±0.3 kPa (120±2 mmHg). The water permeability of the prepared artificial blood vessels at 16 kPa is shown in the table below.

[0063] Table 1 shows the mass fraction settings of the coating solutions in Examples 1 to 5 and the water permeability of the artificial blood vessels prepared under the corresponding conditions.

[0064] project Collagen solution concentration (%) <![CDATA[Water permeation amount (mL·cm -2 ·min -1 )]]> Example 1 15 13.7 Example 2 10 68.0 Example 3 12 51.0 Example 4 18 31.3 Example 5 20 53.0

[0065] Examples 6 to 8

[0066] The only difference between Examples 6 to 8 and Example 1 is that the inner diameter of the artificial blood vessel is different from that in Example 1. The other steps are basically the same as in Example 1 and will not be repeated here. The inner diameter settings of the artificial blood vessels in Examples 1 and 6 to 8 are shown in Table 2. The artificial blood vessels, coated with a composite fiber containing a collagen solution with a mass fraction of 15%, and with inner diameters of 6, 15, 30, and 40 mm, were all tested within a pressure range of 16.0 ± 0.3 kPa (120 ± 2 mmHg). The amount of water leaking through the sample surface within 60 ± 1 s was collected and measured. The water permeability of the prepared artificial blood vessels at 16 kPa is shown in the table below.

[0067] Table 2 shows the inner diameter settings of the artificial blood vessels in Examples 1 and 6 to 8, and the water permeability of the artificial blood vessels produced under the corresponding conditions.

[0068]

[0069]

[0070] Examples 9 to 11

[0071] The only difference between Examples 9 to 11 and Example 1 is the wall thickness of the artificial blood vessels. The other steps are basically the same as in Example 1 and will not be repeated here. The wall thickness settings for the artificial blood vessels in Examples 1 and 9 to 11 are shown in Table 3. The artificial blood vessels, coated with a composite fiber containing 15% collagen solution by mass, with wall thicknesses of 1.0, 0.5, 1.5, and 2 mm, were all tested within a pressure range of 16.0 ± 0.3 kPa (120 ± 2 mmHg). The amount of water leaking through the sample surface within 60 ± 1 s was collected and measured. The water permeability of the prepared artificial blood vessels at 16 kPa is shown in the table below.

[0072] Table 3 shows the wall thickness of the artificial blood vessels in Examples 1 and 9 to 11 and the water permeability of the artificial blood vessels prepared under the corresponding conditions.

[0073] project Wall thickness of artificial blood vessels (mm) <![CDATA[Water permeation amount (mL·cm -2 ·min -1 )]]> Example 1 1.0 13.7 Example 9 0.5 54.2 Example 10 1.5 23.0 Example 11 2.0 27.5

[0074] Examples 12 to 14

[0075] The only difference between Examples 12 to 14 and Example 1 is that the thickness of the composite fiber in step S1 and the thickness of the warp yarn in step S4 are different from those in Example 1. The other steps are basically the same as in Example 1 and will not be repeated here. The thickness settings of the composite fiber and warp yarn in Examples 1 and 12 to 14 are shown in Table 4. The composite fiber coated with a collagen solution containing 10% by mass has composite fiber densities of 100, 60, 150, and 200D, corresponding to warp yarn densities of 100, 60, 150, and 200D. The artificial blood vessels were prepared under a pressure range of 16.0 ± 0.3 kPa (120 ± 2 mmHg), and the amount of water leaking through the sample surface within 60 ± 1 s was collected and measured. The water permeability of the prepared artificial blood vessels at 16 kPa is shown in the table below. Table 4: Water permeability of the composite fiber and warp yarn settings and artificial blood vessels prepared under corresponding conditions in Examples 1 and 12 to 14.

[0076]

[0077] In summary, the low-permeability braided artificial blood vessel preparation method proposed in this invention involves twisting polyester filaments and absorbent fibers into composite fibers, then forming a collagen solution coating on the surface and drying it. The composite fibers are used as weft yarns, and the warp and weft yarns are interwoven through a weaving process to form the artificial blood vessel. The prepared artificial blood vessel is then immersed in deionized water, followed by post-treatments such as pressure application, shaping, and drying. After absorbing water, the weft yarns swell; after pressure treatment, the weft yarns are compressed and deformed into a flat shape to fill the gaps; simultaneously, during water absorption, the collagen solution generates viscosity, making the warp and weft yarns adhere more firmly upon contact. This physical processing improves the water absorption of the artificial blood vessel, reduces its blood permeability, and effectively solves the problems of high permeability and bleeding caused by loose fabric structure in existing textile-type artificial blood vessels. The post-treatment of the composite fibers not only facilitates the bonding between the coating and the composite fibers but also increases the surface area of ​​the functional fibers, which is beneficial for further bonding between the composite fibers as weft and warp yarns in the subsequent weaving of the artificial blood vessel. In the above process, artificial blood vessels that are suitable for cell growth and adhesion, have good elasticity, have a tight tissue structure, and have anticoagulant and anti-bleeding effects can also be prepared by adjusting parameters such as the thickness of the composite fiber, the concentration of the coating, the inner diameter of the artificial blood vessel, and the thickness of the blood vessel wall.

[0078] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a low-permeability braided artificial blood vessel, characterized in that, Includes the following steps: S1. After arranging the absorbent fibers in parallel on both sides of the polyester filament, the fibers are twisted. The mass ratio of the polyester filament to the absorbent fibers is (1:0.1)-(1:0.5), the twist direction is Z twist or S twist, and the twist degree is 100-500 twists / m, thus obtaining the composite fiber. S2. Add collagen to distilled water and stir at 200-800 r / min at 20-60℃ for 18-24 hours. Let it stand for 10 hours to remove bubbles, and a uniform collagen solution will be obtained. S3. After immersing the composite fiber obtained in step S1 into the collagen solution, remove it and uniformly coat the surface of the composite fiber with the collagen solution. Then, dry the composite fiber at 80°C for 1-3 hours to form a coating on the surface of the composite fiber. The thickness of the coating is 0.1-10 μm and the content of the coating is 1-10% of the weight of the composite fiber. S4. The composite fiber obtained in step S1 is used as weft yarn and woven in a dry environment. The weaving equipment used in this process is a shuttle loom, the warp yarn is polyester, the warp yarn is hooked with a reed hook and pulled out from the reed eye, and then the warp yarn is introduced into the reed teeth with a reed inserter. The warp yarn and the weft yarn are woven together to form a tubular fabric, and the woven artificial blood vessel can be obtained. S5. The braided artificial blood vessel obtained in step S4 is subjected to post-processing. The post-processing steps are as follows: first, the braided artificial blood vessel is soaked in distilled water for 5-10 minutes to allow the composite fibers to expand; then, a pressure of 0.5-1 MPa is applied to both sides of the wall of the braided artificial blood vessel for 10-60 seconds; next, it is heated and shaped at 100-120°C for 20-60 minutes; finally, it is dried at 80°C for 1-3 hours to obtain the low-permeability braided artificial blood vessel.

2. The method for preparing a low-permeability braided artificial blood vessel according to claim 1, characterized in that, In step S1, the absorbent fiber is one of alginate fiber, cellulose-based superabsorbent fiber, or polyvinyl alcohol-based superabsorbent fiber.

3. The method for preparing a low-permeability braided artificial blood vessel according to claim 1, characterized in that, In step S1, the composite fiber has a diameter of 60-200D and a number of filaments of 20-150.

4. The method for preparing a low-permeability braided artificial blood vessel according to claim 1, characterized in that, In step S2, the collagen is one of fish collagen, porcine collagen, or bovine collagen, the molecular weight of the collagen is 1-100,000, and the mass fraction of the collagen protein solution is 5-20%.

5. The method for preparing a low-permeability braided artificial blood vessel according to claim 1, characterized in that, In step S4, the polyester warp yarn in the woven artificial blood vessel has a thickness of 60-300D and a number of 20-100 filaments.

6. The method for preparing a low-permeability braided artificial blood vessel according to claim 1, characterized in that, In step S4, the fabric structure for weaving the artificial blood vessel is one of plain weave, twill weave, or satin weave.

7. The method for preparing a low-permeability braided artificial blood vessel according to claim 1, characterized in that, In step S4, the warp density of the braided artificial blood vessel is 100-600 threads / 5cm, and the weft density of the braided artificial blood vessel is 100-600 threads / 5cm.

8. The method for preparing a low-permeability braided artificial blood vessel according to claim 1, characterized in that, In step S4, the inner diameter of the braided artificial blood vessel is 6-40 mm, and the wall thickness of the braided artificial blood vessel is 0.5-2 mm.

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