A method for preparing a surface-graded porous structure

Abstract

The application discloses a preparation method of a surface gradientized porous structure and belongs to the technical field of polyether ether ketone processing. Under high-temperature conditions, continuous carbon fiber reinforced polyether ether ketone composite wire is sequentially laid on the surface of a base body according to a certain rule, the arrangement density or spacing of the wire is adjusted through gradient adjustment, the size of the pore structure is adjusted, a multilayer gradient net-shaped pore structure with inner dense and outer sparse, large pore layer thickness and pore size range and high pore wall strength is obtained, and the base body, the wire and the wire are tightly fused into an integrated whole through molten polyether ether ketone. The preparation process is simple, and the multilayer gradient net-shaped pore structure can be formed at one time without the use of a porogen, a foaming agent and a chemical etchant, and the like, so that complicated cleaning treatment procedures in the later stage are avoided.

Description

Technical Field

[0001] This invention relates to the field of polyetheretherketone (PEEK) processing technology, and more specifically, to a method for preparing a surface-gradient porous structure. Background Technology

[0002] In existing technologies, porous polyetheretherketone (PEEK) is prepared using wet chemical methods and hot pressing methods. The hot pressing method incorporates inorganic salt particles into the PEEK surface, followed by solution dissolution of the inorganic salt particles, thereby forming a porous structure on the PEEK material surface. The wet chemical method involves immersing the PEEK material in an 80%–100% sulfuric acid aqueous solution at room temperature for 0.5–9 minutes, followed by immersion in a cleaning agent at 0°C–100°C in water, ethanol, dimethyl sulfoxide, ethylene glycol, a water / ethanol mixed solvent, a water / dimethyl sulfoxide mixed solvent, or a 37–83% sulfuric acid aqueous solution for 10 minutes, resulting in a polyetheretherketone resin with a porous surface structure.

[0003] 1. In the traditional hot pressing method, the pore-forming agent used in the preparation process needs to be completely precipitated and dried, which takes a long time, consumes a lot of energy, and there is a possibility of incomplete removal.

[0004] 2. Porous structures prepared by chemical methods have limited porous layer thickness and small pore size, making it difficult to achieve micron- or even millimeter-scale pore structures, which is not conducive to the ingrowth of bone tissue, blood vessels, etc. Summary of the Invention

[0005] To address the problems existing in the aforementioned background technology, this invention proposes a method for preparing a surface-gradient porous structure. The preparation process is simple, can be completed in one step, and does not require the use of pore-forming agents, foaming agents, or chemical etchants, thus avoiding complex subsequent cleaning procedures.

[0006] The technical solution of this invention is implemented as follows:

[0007] A method for preparing a surface gradient porous structure specifically includes the following steps:

[0008] Under high temperature conditions, continuous carbon fiber reinforced polyether ether ketone composite filaments are laid layer by layer on the surface of the matrix according to a certain pattern. The pore structure size is adjusted by gradient adjustment of the filament arrangement density or spacing, resulting in a multi-layer gradient mesh pore structure with dense inner and sparse outer pores, a large range of pore layer thickness and pore size, and high pore wall strength. The matrix and filaments, as well as the filaments themselves, are tightly fused together by molten polyether ether ketone.

[0009] Furthermore, the carbon fiber reinforced polyetheretherketone composite filament includes polyetheretherketone resin and multiple continuous carbon fiber monofilaments; the polyetheretherketone resin is wrapped around the outside of the continuous carbon fiber monofilaments.

[0010] Furthermore, the diameter of the continuous carbon fiber reinforced polyether ether ketone composite filament is 0.05 mm to 1.2 mm.

[0011] Furthermore, continuous carbon fiber reinforced polyether ether ketone composite filaments are laid on the matrix surface in multiple directions, with the corresponding number of layers for each direction, until the target thickness is achieved, and the number of arrangement directions is ≥2.

[0012] Furthermore, when changing the direction of the layup or carrying out a new round of layup, the density of the filament arrangement is reduced and the spacing between the filaments is increased, thereby obtaining a gradient porous structure with a denser interior and a sparser exterior.

[0013] Furthermore, the filament laying temperature is 350℃ to 400℃.

[0014] Furthermore, the matrix material is polyetheretherketone or carbon fiber reinforced polyetheretherketone composite material.

[0015] Furthermore, the total thickness of the porous structure layer on the outer side of the matrix is ​​0.3 mm to 6 mm.

[0016] Furthermore, the diameter of the outermost hole in the gradient mesh structure ranges from 0.05 mm to 2 mm.

[0017] Compared with the prior art, the advantages of the present invention are as follows:

[0018] 1. This technology can prepare pore structures with large pore thickness and large pore size (micrometer to millimeter), and the pore size distribution is uniform with good pore connectivity, making it more suitable for bone ingrowth;

[0019] 2. The pore walls are made of carbon fiber reinforced polyether ether ketone composite material, which has higher mechanical strength than pure polyether ether ketone, has better load-bearing capacity, and is not easily cracked or damaged.

[0020] 3. The preparation process is simple and can be formed in one step without the need for pore-forming agents, foaming agents and chemical etchants, thus avoiding complicated cleaning processes in the later stage.

[0021] 4. This technology is highly operable and process controllable. It is not only easy to obtain pore layers of different sizes and thicknesses, but also to obtain a gradient distribution of porous structures by adjusting the density of the wire arrangement. Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0023] This invention relates to a method for preparing a gradient porous structure on the surface of a polyetheretherketone (PEEK)-based material. Continuous carbon fiber reinforced PEEK composite filaments are laid layer by layer onto the surface of a PEEK matrix material according to a specific pattern. The pore size is adjusted by gradient-adjusting the filament arrangement density or spacing, resulting in a multi-layered gradient mesh structure with a denser inner layer and a sparser outer layer, a wide range of pore thickness and diameter, and high pore wall strength. The filament laying is performed at high temperature, and the matrix and filaments, as well as the filaments themselves, are tightly fused together by molten PEEK.

[0024] Furthermore, the continuous carbon fiber reinforced polyetheretherketone composite filament is composed of several continuous carbon fiber monofilaments and polyetheretherketone resin covering the monofilaments.

[0025] Furthermore, the diameter of the continuous carbon fiber reinforced polyetheretherketone composite filament is 0.05 mm to 1.2 mm.

[0026] Furthermore, continuous carbon fiber reinforced polyether ether ketone composite filaments are laid on the matrix surface in a certain direction. After the first layer is laid, the operation is repeated to lay a layers in total. Then, layer b is laid in the second direction, layer c is laid in the third direction, and so on, to complete the first round of laying. Then, the laying process is repeated until the target thickness is achieved, and the number of orientation directions is ≥2.

[0027] Furthermore, when changing the direction of the layup or carrying out a new round of layup, the density of the filament arrangement is reduced and the spacing between the filaments is increased, thereby obtaining a gradient porous structure with a denser interior and a sparser exterior.

[0028] Furthermore, the thickness of the porous structure layer on the surface is 0.3 mm to 6 mm, preferably 0.5 mm to 3 mm.

[0029] Furthermore, the diameter of the outermost hole in the porous structure ranges from 0.05 mm to 2 mm.

[0030] Furthermore, the filament laying temperature is 350℃~400℃.

[0031] Furthermore, the matrix is ​​pure polyetheretherketone or carbon fiber reinforced polyetheretherketone composite material, or a resin material with properties similar to polyetheretherketone.

[0032] The following examples further illustrate this:

[0033] Example 1: A gradient porous structure was prepared on the surface of a polyetheretherketone material.

[0034] Continuous carbon fiber reinforced polyetheretherketone (PEEK) composite filaments with a diameter of 1.2 mm were laid on the surface of PEEK material at 0°. Then, the filament laying direction was changed, the filament density was reduced, and the filament spacing was increased. One layer was then laid at 90°. After the first round of laying, a second round of laying began, with one layer laid at 0° while increasing the filament spacing, followed by another layer laid at 90° while continuing to increase the filament spacing. After the second round of laying, another layer was laid at 0° while increasing the filament spacing. The final product was a porous structure layer with a thickness of 6 mm and an outermost pore size of 2 mm. The filament laying temperature was 400℃. The matrix and filaments, as well as the filaments themselves, were tightly fused together by the high-temperature molten PEEK, completing the preparation of the gradient porous structure on the PEEK surface.

[0035] Example 2: A gradient porous structure was prepared on the surface of a short carbon fiber reinforced polyether ether ketone material.

[0036] Continuous carbon fiber reinforced polyetheretherketone (PEEK) composite filaments with a diameter of 0.6 mm were laid on the surface of short carbon fiber reinforced PEEK material at 0°. After one layer was laid, the filament laying direction was changed to 45°, and another layer was laid. After the first round of laying, a second round of laying began, repeating the operation of the first round, but with a reduced filament density and increased filament spacing. After the second round of laying, another layer was laid at 0°, with the filament spacing increased again. After the second round of laying, a porous structure layer with a thickness of 3 mm and an outermost pore size of 1 mm was obtained. The filament laying temperature was 390℃. The matrix and filaments, as well as the filaments themselves, were tightly fused together by the high-temperature molten PEEK, completing the preparation of the gradient porous structure on the surface of the short carbon fiber reinforced PEEK material.

[0037] Example 3: A gradient porous structure was prepared on the surface of a continuous carbon fiber reinforced polyetheretherketone material.

[0038] Continuous carbon fiber reinforced polyetheretherketone (PEEK) composite filaments with a diameter of 0.05 mm were laid on the surface of the continuous carbon fiber reinforced PEEK material at 0°. This process was repeated for two layers. Then, the filament laying direction was changed, the filament density was reduced, and the filament spacing was increased. Two layers were laid at 90°. After the first round of laying, the second round began, with two layers laid at 0° while increasing the filament spacing. Then, two layers were laid at 90° while continuing to increase the filament spacing. After the second round, two more layers were laid at 0° while increasing the filament spacing. This resulted in a porous structure layer with a thickness of 0.5 mm and an outermost pore size of 0.05 mm. The filament laying temperature was 360℃. The matrix and filaments, as well as the filaments themselves, were tightly fused together by the high-temperature molten PEEK, completing the preparation of the gradient porous structure on the surface of the continuous carbon fiber reinforced PEEK material.

[0039] Example 4: A gradient porous structure was prepared on the surface of a polyetheretherketone material.

[0040] Continuous carbon fiber reinforced polyetheretherketone (PEEK) composite filaments with a diameter of 0.1 mm were laid on the surface of the PEEK material at 0°. This process was repeated for two layers. Then, the filament laying direction was changed to 90°, and two more layers were laid at 45°, completing the first round of laying. The second round of laying followed the same procedure as the first, but with a reduced filament density and increased filament spacing. After the second round, a third round of laying began, continuing to increase the filament spacing. Two layers were laid at 0°, followed by two more at 90°, resulting in a porous structure layer with a thickness of 2 mm and an outermost pore size of 0.5 mm. The filament laying temperature was 370℃. The matrix and filaments, as well as the filaments themselves, were tightly fused together by the high-temperature molten PEEK, completing the preparation of the graded porous structure on the PEEK surface.

[0041] The above description is merely an embodiment of the present invention, but the present invention is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit and principles of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A method for preparing a surface-gradient porous structure, characterized in that, Specifically, the process includes the following: Under high temperature conditions, continuous carbon fiber reinforced polyether ether ketone composite filaments are laid layer by layer on the surface of the matrix according to a certain rule, and the pore structure size is adjusted by gradient adjustment of the filament arrangement density or spacing, resulting in a multi-layer gradient network pore structure with dense inner and sparse outer pores, a large range of pore layer thickness and pore size, and high pore wall strength. The matrix and filaments, as well as the filaments themselves, are tightly fused together by molten polyether ether ketone. The carbon fiber reinforced polyetheretherketone composite filament includes polyetheretherketone resin and multiple continuous carbon fiber monofilaments; the polyetheretherketone resin is wrapped around the outside of the continuous carbon fiber monofilaments; Continuous carbon fiber reinforced polyether ether ketone composite filaments are laid on the matrix surface in multiple directions, with the corresponding number of layers for each direction laid until the target thickness is achieved, and the number of arrangement directions is ≥2. When changing the direction of the layup or making a new round of layup, the density of the filament arrangement is reduced and the spacing between the filaments is increased, thereby obtaining a gradient porous structure that is dense inside and sparse outside. The temperature for laying the filament is 350℃ to 400℃.

2. The method for preparing a surface-gradient porous structure according to claim 1, characterized in that, The diameter of the continuous carbon fiber reinforced polyether ether ketone composite filament is 0.05 mm to 1.2 mm.

3. The method for preparing a surface-gradient porous structure according to claim 1, characterized in that, The matrix material is polyetheretherketone or carbon fiber reinforced polyetheretherketone composite material.

4. The method for preparing a surface-gradient porous structure according to claim 1, characterized in that, The total thickness of the porous structure layer on the outer side of the matrix is ​​0.3mm to 6mm.

5. The method for preparing a surface-gradient porous structure according to claim 1, characterized in that, The diameter of the outermost hole in the gradient mesh structure ranges from 0.05 mm to 2 mm.