A prosthetic heart valve composite and method of making the same

Abstract

The application provides an artificial heart valve composite material and a preparation method thereof. The composite material can be prepared by the following steps: firstly, preparing a thermoplastic polymer film on a low-barrier smooth substrate; and then using the clamping effect of the polymer film on the fabric; or firstly, forming a thermoplastic polymer film on the surface of the fabric; and then using a good solvent of the thermoplastic polymer film to partially dissolve the thermoplastic polymer film; under the fixing effect of the low-barrier smooth substrate, the polymer film is solidified again, and the polymer film and the fabric are combined, so that the artificial heart valve composite material is finally prepared. By using the preparation method provided by the application, the prepared composite material has a smooth and uniform surface, the fabric and the polymer layer are combined tightly, and there is no obvious interface.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an artificial heart valve composite material and its preparation method. Background Technology

[0002] Textile-based artificial heart valves, manufactured using textile technology, offer numerous advantages. They allow for precise control over the composition, thickness, and structure of the stent material to optimize the interventional process and adjust the final geometry and biomechanical properties of the product. Therefore, they have broad application prospects in surgical valves, transcatheter valves, valved conduits, and tissue-engineered valves. Current research on textile-based artificial heart valve leaflets typically uses pure fabrics or fabric-based composites composed of polymer fibers / yarns. However, pure fabrics suffer from leakage, structural deformation, and surface roughness that can lead to thrombosis. Composite materials, obtained by combining polymers, reduce leakage, improve structural stability, and reduce surface roughness, offering advantages over pure fabrics in blood-use environments. However, the inherent texture of the fabric surface makes it difficult to ensure uniform polymer layer thickness during polymer modification, potentially trapping blood substances and increasing the risk of thrombosis or calcification during use.

[0003] Currently, the molding method for fabric-based composite materials generally involves impregnating the fabric with polymers under heating and pressure or in solvents, thereby achieving polymer penetration into the fabric. However, for medical-grade composite materials, heating and pressure may have adverse effects on the polymer or the fabric.

[0004] In view of this, it is necessary to design an improved artificial heart valve composite material and its preparation method to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide an artificial heart valve composite material and its preparation method.

[0006] To achieve the above-mentioned objectives, in one aspect, the present invention provides an artificial heart valve composite material, comprising:

[0007] Fabrics;

[0008] Two thermoplastic polymer films are respectively disposed on both sides of the fabric and tightly bonded to the surface of the fabric. The thickness of the thermoplastic polymer film is 5-1000 μm; the surface roughness of the composite material is <200 nm.

[0009] On the other hand, the present invention also provides a method for preparing the above-mentioned artificial heart valve composite material, comprising the following steps:

[0010] A thermoplastic polymer film is formed on the surface of a substrate with low barrier properties and a smooth surface. A wet fabric is placed between two substrates with thermoplastic polymer films, so that the thermoplastic polymer film is bonded to the fabric. After the whole is dried, the fabric bonded to the thermoplastic polymer film is separated from the substrate, thus obtaining the artificial heart valve composite material.

[0011] Preferably, the thermoplastic polymer film is formed by curing a thermoplastic polymer solution on the substrate, wherein the mass-volume fraction of the thermoplastic polymer solution is 10-25 w / v.

[0012] Preferably, the solute of the thermoplastic polymer solution is one or more of polyurethane, polycarbonate-polyurethane copolymer, polysiloxane-polyurethane copolymer, and styrene / isobutylene copolymer, and the solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

[0013] Preferably, the surface roughness Ra of the substrate is <200 nm, and its material is one or more of polyethylene, polypropylene, and silicone; the oxygen permeability of the substrate is 1000-10000 cm⁻¹. 3 / (m 2 • 24h • 0.1MPa) or the water vapor transmission rate of the substrate is 1-20 g / (m 2 •24h).

[0014] Preferably, the moistened fabric is obtained by fully impregnating the fabric with a first solvent, wherein the first solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

[0015] Preferably, the fabric has a thickness of 10-1000 μm and is made of one or more of polyester, polyethylene, polypropylene, polyamide, and polyvinyl chloride.

[0016] Furthermore, the above-mentioned artificial heart valve composite material can also be prepared by the following method, including the following steps:

[0017] A thermoplastic composite material is provided, the thermoplastic composite material comprising a fabric having thermoplastic polymer films on both sides; the preparation method of the thermoplastic composite material comprises immersing the fabric in a thermoplastic polymer solution, and then removing and drying it to form a thermoplastic polymer film on the surface of the fabric.

[0018] A first solvent is coated on a substrate with low barrier properties and a smooth surface, and a thermoplastic composite material is laid flat on the substrate so that the thermoplastic polymer film on one side of the fabric is wetted by the first solvent.

[0019] Then, a second solvent is coated on the surface of the thermoplastic polymer film on the other side of the fabric. Another substrate with low barrier properties and a smooth surface is placed on the fabric surface. The two substrates are squeezed to make the thermoplastic composite material adhere tightly to the substrate. After the whole is dried, the treated thermoplastic composite material is separated from the substrate to obtain the artificial heart valve composite material.

[0020] The first solvent and the second solvent are capable of dissolving the thermoplastic polymer film.

[0021] Preferably, the thermoplastic polymer solution has a mass-volume fraction of 10-25 w / v%, and the solute of the polymer solution is one or more of polyurethane, polycarbonate-polyurethane copolymer, polysiloxane-polyurethane copolymer, and styrene / isobutylene copolymer, and the solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

[0022] Preferably, the first solvent and / or the second solvent are independently selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

[0023] The beneficial effects of this invention are:

[0024] 1. The method for preparing artificial heart valve composite material provided by this invention involves first preparing a thermoplastic polymer film on a smooth substrate with low barrier properties, and then using the clamping effect of the polymer film on the fabric to achieve the shaping process of the polymer film on the fabric surface. In this process, the surface properties of the substrate can be fully utilized, giving the composite material a smooth surface. Secondly, after wetting the fabric with a solvent, the polymer film on the fabric surface is modified. The solvent can partially dissolve the polymer film, allowing the polymer to penetrate into the fabric, forming a "bridge" between the two polymer films and achieving the composite of the fabric and the polymer film. This process eliminates the need for pretreatment of the fabric, reducing the impact on the fabric's own properties during preparation and ensuring that the composite material retains the fabric's inherent softness and other properties, thus giving the composite material excellent performance. By wetting the fabric before compositing it with the polymer film, the fabric can be fully spread out, and the fabric and polymer film can be in full contact, facilitating the composite between the polymer film and the fabric, ensuring that the fabric remains flat in the composite material, and improving the overall integrity of the composite material.

[0025] 2. The method for preparing the artificial heart valve composite material provided by this invention involves first forming a thermoplastic polymer film on the surface of a fabric, then partially dissolving the thermoplastic polymer film using a good solvent. Under the fixation of a smooth substrate with low barrier properties, the polymer film is then cured again, simultaneously achieving the composite of the polymer film and the fabric. The final product is a composite material with a uniform and flat surface and no obvious interface (contact interface between the polymer film and the fabric). In the above technical solution, the fixation effect of the substrate and the negative pressure generated during the solvent evaporation process in the polymer film facilitate the curing of the polymer film. Therefore, this process can be achieved at a relatively low temperature, avoiding damage to the properties of the polymer layer and the fabric during polymer molding. Furthermore, the fabric and polymer film, after being extruded using the substrate, can better maintain a flat state during the subsequent drying process, ensuring that the final composite material has a flat and uniform surface. Attached Figure Description

[0026] Figure 1 This is a cross-sectional view of the composite material obtained in Example 1 of the present invention;

[0027] Figure 2 Here is a surface SEM image of the composite material obtained in Example 1 of this invention;

[0028] Figure 3 This is a cross-sectional view of the composite material obtained in Example 4 of the present invention;

[0029] Figure 4 Here is a surface SEM image of the composite material obtained in Example 4 of this invention;

[0030] Figure 5 Here is a surface SEM image of the composite material prepared in Comparative Example 1 of this invention;

[0031] Figure 6 This is a cross-sectional view of the composite material obtained in Comparative Example 2 of the present invention. Detailed Implementation

[0032] 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.

[0033] 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.

[0034] 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.

[0035] This invention provides an artificial heart valve composite material, comprising:

[0036] Fabrics;

[0037] Two thermoplastic polymer films are respectively disposed on both sides of the fabric and tightly bonded to the surface of the fabric. The thickness of the thermoplastic polymer film is 5-1000μm, and the surface roughness of the composite material is <200nm.

[0038] In particular, the present invention also provides a method for preparing the above-mentioned artificial heart valve composite material, comprising the following steps:

[0039] A thermoplastic polymer film is formed on the surface of a substrate with low barrier properties and a smooth surface. A wet fabric is placed between two substrates with thermoplastic polymer films, so that the thermoplastic polymer film and the fabric are bonded together. After the whole is dried, the fabric bonded to the thermoplastic polymer film is separated from the substrate, thus obtaining the composite material.

[0040] In the above technical solution, a polymer film is first prepared on a smooth substrate, and then partially dissolved and transferred to the fabric to prepare a polymer layer on the fabric surface. The side of the polymer film in contact with the substrate obtained by the above method retains the smooth and flat surface characteristics of the substrate surface, ensuring that the final composite material has a smooth, flat, and uniform thickness. Secondly, after wetting the fabric, the polymer film on the fabric surface is shaped, omitting the pretreatment step of the fabric and avoiding the impact of the pretreatment process on the fabric's permeability, softness, and other properties. Therefore, the composite material can well retain the softness of the fabric, giving it excellent performance (e.g., opening and closing properties). By utilizing the dissolution effect of the solvent attached to the fabric on the polymer film and the extrusion effect of the substrate on the fabric, the polymer on the fabric surface is modified. The polymer produced by the dissolution of the polymer film will penetrate into the fabric, forming a "connecting bridge" between the two polymer films, enhancing the connection between the two polymer films and improving the overall integrity of the composite material.

[0041] In one embodiment of the present invention, the wetted fabric is obtained by fully immersing the fabric in a first solvent, wherein the first solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

[0042] In the above technical solution, by immersing the fabric in the solvent, not only can the fabric be easily flattened, ensuring that the fabric remains flat during the modification process, but the solvent on the fabric can also partially dissolve the polymer film and facilitate the dissolved polymer to enter the fabric interior, so that there is no obvious interface between the fabric and the polymer layer in the composite material, ensuring the overall stability of the composite material.

[0043] In one embodiment of the present invention, the second solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

[0044] In one embodiment of the present invention, the polymer film is formed by curing a thermoplastic polymer solution on a substrate. The thermoplastic polymer solution has a mass-volume fraction of 10-25 w / v, and the solute is one or more of polyurethane, polycarbonate-polyurethane copolymer, polysiloxane-polyurethane copolymer, and styrene / isobutylene copolymer. The solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

[0045] As one embodiment of the present invention, the polymer film is formed by means of, but not limited to, spraying, blade coating, dip coating, spin coating, and roll coating.

[0046] Furthermore, the composite material can also be prepared by providing a thermoplastic composite material, which includes a fabric with thermoplastic polymer films on both sides;

[0047] The method for preparing thermoplastic composite materials includes immersing a fabric in a thermoplastic polymer solution, removing it and drying it to form a thermoplastic polymer film on the fabric surface; then, coating a first solvent onto a substrate with low barrier properties and a smooth surface, and laying the thermoplastic composite material flat on the substrate so that the thermoplastic polymer film on one side of the fabric is wetted by the first solvent; then, coating the surface of the thermoplastic polymer film on the other side of the fabric with a second solvent, and then placing another substrate with low barrier properties and a smooth surface on the fabric surface, pressing the two substrates to make the thermoplastic composite material adhere tightly to the substrates, drying the whole thing, and then separating the treated thermoplastic composite material from the substrates to obtain the composite material.

[0048] The preparation method proposed in this invention involves forming a polymer film, partially dissolving it, and then curing it under the pressure of a substrate. This process effectively avoids air bubbles between the fabric and the polymer film. Furthermore, as the solvent in the polymer film evaporates, a certain amount of negative pressure is generated. Combined with the pressure from the substrate, this facilitates the curing process. Therefore, this process can be achieved at a relatively low temperature, avoiding damage to the properties of the polymer layer and the fabric during polymer modification. Secondly, the fabric and polymer film after being extruded by the substrate can better maintain a flat state during the subsequent drying process, ensuring that the final composite material has a smooth and uniform surface.

[0049] In one embodiment of the present invention, the surface roughness Ra of the substrate is <200 nm, and the oxygen permeability of the substrate is 1000-10000 cm⁻¹. 3 / (m 2 • 24h • 0.1MPa) or the water vapor transmission rate of the substrate is 1-20 g / (m 2 •24h), its material is one or more of polyethylene, polypropylene, and silicone, and it is used in the form of release paper or silicone pad. By selecting a material with a smooth surface and low barrier properties as the substrate, it is not only beneficial for the polymer solution to form a polymer film on the substrate surface, but also to avoid the separation of the fabric from the polymer layer during the subsequent separation of the polymer-modified fabric from the substrate, thus avoiding affecting the integrity of the composite material.

[0050] In one embodiment of the present invention, the material of the fabric is one or more of polyester, polyethylene, polypropylene, polyamide and polyvinyl chloride, the weave structure is one of woven, knitted or nonwoven, the texture structure is plain weave, twill weave, satin weave, etc., and the thickness is 10-1000μm.

[0051] The artificial heart valve composite material and its preparation method proposed in this invention will be further explained below with reference to specific embodiments:

[0052] Example 1

[0053] This embodiment prepares an artificial heart valve composite material. The preparation method includes the following steps:

[0054] A polyurethane dry film with a thickness of approximately 30 μm was prepared on polyethylene release paper using a 20 w / v polyurethane / N,N-dimethylacetamide solution. A 40 μm thick polyethylene woven fabric (plain weave) was fully impregnated with N,N-dimethylacetamide, then sandwiched between two sheets of release paper. Excess solvent was squeezed out, allowing the polyurethane film to bond with the fabric. After drying, the release paper and the fabric bonded to the polyurethane film were separated to obtain the composite material. The cross-sectional view of the composite material prepared in this embodiment is shown below. Figure 1As shown in the figure, the fabric and polymer layers in the material are tightly bonded together, and there is no obvious interface between them; the overall planar surface SEM image is shown below. Figure 2 As shown in the figure, the surface of the composite material is smooth.

[0055] Example 2

[0056] This embodiment prepares an artificial heart valve composite material. The preparation method includes the following steps:

[0057] A polyurethane dry film with a thickness of approximately 50 μm was prepared on release paper (polyethylene material) using a polyurethane / N,N-dimethylacetamide solution with a mass-volume fraction of 15 w / v. A polyethylene woven fabric with a thickness of 50 μm (plain weave structure) was fully impregnated in dimethyl sulfoxide, removed, sandwiched between two release papers, and excess solvent was squeezed out to bond the polyurethane film with the fabric. After drying, the release paper and the fabric bonded to the polyurethane film were separated to obtain the composite material.

[0058] Example 3

[0059] This embodiment prepares an artificial heart valve composite material. The preparation method includes the following steps:

[0060] A polystyrene dry film with a thickness of approximately 100 μm was prepared on a silicone pad using a polystyrene / dichloromethane solution with a mass-volume fraction of 20 w / v. A 30 μm thick polyester nonwoven fabric (with a plain weave structure) was fully impregnated in dichloromethane, removed, and sandwiched between two silicone pads. Excess solvent was squeezed out, and the polystyrene film and nonwoven fabric bonded together. After drying, the silicone pads and the nonwoven fabric bonded to the polystyrene film were separated to obtain the composite material.

[0061] Example 4

[0062] This embodiment prepares an artificial heart valve composite material. The preparation method includes the following steps:

[0063] A 40 μm thick polyethylene woven fabric was immersed in a 20 w / v polyurethane / N,N-dimethylformamide solution, dried, and cured to obtain a thermoplastic composite material. This thermoplastic composite material is a polyethylene fabric with polyurethane films on both sides. A certain amount of N,N-dimethylformamide was dropped onto release paper (polypropylene), and the above thermoplastic composite material was flatly attached to it. Excess solvent was drained, making the polyurethane film on one side of the thermoplastic composite material adhere tightly to the release paper. Next, a certain amount of N,N-dimethylformamide was dropped onto the surface of the polyurethane film on the other side of the thermoplastic composite material. Another piece of release paper was taken and flatly attached to it, and excess solvent was drained, making the polyurethane film on the other side of the thermoplastic composite material adhere tightly to the release paper. The entire assembly was thoroughly dried, and after removing the release paper, the shaped thermoplastic composite material was obtained. The cross-sectional view of the thermoplastic composite material obtained in this embodiment is shown below. Figure 3 As shown in the figure, the fabric and polymer layers in the material are tightly bonded together, with no obvious interface between them. The thickness of the polymer layer does not change significantly along the extension direction of the thermoplastic composite material, and the thickness of the polymer layer is uniform. The overall planar surface SEM image is shown below. Figure 4 As shown in the figure, the surface of the composite material is smooth.

[0064] Comparative Example 1

[0065] A 40 μm thick polyethylene woven fabric was immersed in a 20 w / v polyurethane / N,N-dimethylformamide solution, dried, and cured to obtain a thermoplastic composite material. This thermoplastic composite material is a polyethylene fabric with polyurethane films on both sides. The surface SEM image of the composite material obtained in Comparative Example 1 is shown below. Figure 5 As shown, the surface of the composite material retains the texture structure of the fabric.

[0066] Comparative Example 2

[0067] The preparation method of Comparative Example 2 is as follows: A polymer solution is coated onto cellophane. When the solution is semi-dry (not flowing), a dry fabric is sandwiched between two pieces of cellophane containing the polymer solution. After drying and curing, the composite material is obtained. The process parameters are the same as in Example 1 and will not be repeated here. A cross-sectional view of the composite material obtained in Comparative Example 2 is shown below. Figure 6 As shown in the figure, the composite material cracks during use, and there is a clear interface between the fabric and the polymer. This is because when the dry fabric comes into contact with the semi-dry polymer solution, the polymer solution does not penetrate into the fabric. The fabric and the polymer are only bonded by the pressure of the two sheets of cellophane, and the bonding force between them is limited.

[0068] Table 1 shows a comparison of the properties of the composite materials obtained in Examples 1-4 and Comparative Examples 1-2. As can be seen from the table, compared to bare fabric (unmodified fabric), the composite materials obtained in Examples 1-4 exhibit significantly reduced surface roughness and a smoother surface; the softness is also improved, indicating increased stability of the fabric structure. Compared to Comparative Examples 1-2, the composite materials obtained in Examples 1-4 have a smoother surface and a more stable structure. This is because both polymer penetration into the fabric and surface smoothing modification are indispensable. In Examples 1-3, polymer penetration into the fabric is achieved during the polymer film-fabric composite process, and surface smoothing modification is performed using a substrate during the composite process. In Example 4, polymer penetration into the fabric is ensured during the preparation of the thermoplastic composite material, and then the dissolution properties of the polymer on the fabric surface are utilized in conjunction with the substrate to achieve surface smoothing modification.

[0069] Table 1. Performance comparison of composite materials obtained in Examples 1-4 and Comparative Examples 1-2

[0070] project Average surface roughness (nm) Average softness (mN) Unfinished fabric 2310 25 Example 1 120 94 Example 2 132 105 Example 3 116 78 Example 4 119 90 Comparative Example 1 1867 68 Comparative Example 2 165 63

[0071] 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 composite material for artificial heart valves, characterized in that, include: Fabrics; Two thermoplastic polymer films are respectively disposed on both sides of the fabric and tightly bonded to the surface of the fabric. The thickness of the thermoplastic polymer film is 5-1000 μm; the surface roughness of the composite material is <200 nm.

2. A method for preparing the artificial heart valve composite material as described in claim 1, characterized in that, Includes the following steps: A thermoplastic polymer film is formed on the surface of a substrate with low barrier properties and a smooth surface. A wet fabric is placed between two substrates with thermoplastic polymer films, so that the thermoplastic polymer film is bonded to the fabric. After the whole is dried, the fabric bonded to the thermoplastic polymer film is separated from the substrate, thus obtaining the artificial heart valve composite material.

3. The preparation method according to claim 2, characterized in that, The thermoplastic polymer film is formed by curing a thermoplastic polymer solution on the substrate, wherein the mass-volume fraction of the thermoplastic polymer solution is 10-25 w / v.

4. The preparation method according to claim 3, characterized in that, The solute of the thermoplastic polymer solution is one or more of polyurethane, polycarbonate-polyurethane copolymer, polysiloxane-polyurethane copolymer, and styrene / isobutylene copolymer, and the solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

5. The preparation method according to claim 2 or 3, characterized in that, The substrate has a surface roughness Ra < 200 nm and is made of one or more of polyethylene, polypropylene, and silicone; the oxygen permeability of the substrate is 1000-10000 cm⁻¹. 3 / (m 2 • 24h • 0.1MPa) or the water vapor transmission rate of the substrate is 1-20 g / (m 2 •24h).

6. The preparation method according to claim 2, characterized in that, The moistened fabric is obtained by fully impregnating the fabric with a first solvent, wherein the first solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

7. The preparation method according to claim 6, characterized in that, The fabric has a thickness of 10-1000μm and is made of one or more of polyester, polyethylene, polypropylene, polyamide and polyvinyl chloride.

8. A method for preparing the artificial heart valve composite material as described in claim 1, characterized in that, Includes the following steps: A thermoplastic composite material is provided, the thermoplastic composite material comprising a fabric having thermoplastic polymer films on both sides; the preparation method of the thermoplastic composite material comprises immersing the fabric in a thermoplastic polymer solution, and then removing and drying it to form a thermoplastic polymer film on the surface of the fabric. A first solvent is coated on a substrate with low barrier properties and a smooth surface, and a thermoplastic composite material is laid flat on the substrate so that the thermoplastic polymer film on one side of the fabric is wetted by the first solvent. Then, a second solvent is coated on the surface of the thermoplastic polymer film on the other side of the fabric. Another substrate with low barrier properties and a smooth surface is placed on the fabric surface. The two substrates are squeezed to make the thermoplastic composite material adhere tightly to the substrate. After the whole is dried, the treated thermoplastic composite material is separated from the substrate to obtain the artificial heart valve composite material. The first solvent and the second solvent are capable of dissolving the thermoplastic polymer film.

9. The preparation method according to claim 8, characterized in that, The thermoplastic polymer solution has a mass-volume fraction of 10-25 w / v, and the solute of the polymer solution is one or more of polyurethane, polycarbonate-polyurethane copolymer, polysiloxane-polyurethane copolymer, and styrene / isobutylene copolymer, and the solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

10. The preparation method according to claim 8, characterized in that, The first solvent and / or the second solvent are independently selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, chloroform, dichloromethane, hexafluoroisopropanol, and dioxolane.

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