Medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape and preparation method thereof

Abstract

The invention relates to the technical field of fiber modification, in particular to a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape and a preparation method thereof.The preparation method includes the steps that continuous fibers are subjected to desizing treatment and then immersed in a sizing agent to be subjected to dipping treatment, and after drying, cooling and rolling are conducted to obtain active fibers for standby application; the sizing resin in the sizing agent is a polyether-ether-ketone-imine polymer PEEKI, carrying out adsorption treatment on the active fibers in a PAEK pre-impregnation liquid, and after pre-impregnation, extrusion and shaping, cutting and rolling to obtain the medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape. The polyether-ether-ketone imine polymer is used as a main material of the sizing agent, the surface activity of fibers is improved, the binding force of the fibers and a matrix is enhanced, and the obtained unidirectional prepreg tape has good mechanical properties and is suitable for the fields of medical implants and the like.

Description

Technical Field

[0001] The invention relates to the technical field of fiber modification, and in particular to a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape and a preparation method thereof. Background Art

[0002] Advanced resin-based composite materials have the advantages of high specific strength, high specific modulus, strong designability, corrosion resistance, and easy overall molding. They are widely used in aerospace, transportation, energy, communications and other fields. Among them, thermoplastic resin-based composite materials have unique performance advantages such as high toughness, fatigue resistance, long-term storage, fast molding speed, repeatable processing and easy recycling. As a typical representative, polyaryletherketone (PAEK) is a fully aromatic semi-crystalline thermoplastic engineering plastic. Its molecular chain contains rigid benzene rings, flexible ether bonds and carbonyl groups, with a regular structure, good mechanical properties, chemical corrosion resistance, fatigue resistance and significant thermal stability. In recent years, due to the outstanding properties of continuous fiber reinforced PAEK thermoplastic composites such as high stiffness, high thermal stability, chemical corrosion resistance, wear resistance, and biocompatibility, it is expected to become a structural material and implantable orthopedic material, replacing metal or thermosetting composite materials with mature processes, and is widely used in aerospace, medical, rail transportation and other fields.

[0003] For resin-based composite materials, only high-quality interface performance can effectively exert the mechanical strength of carbon fiber, thereby obtaining a series of excellent properties. An effective interface sizing agent is an important way of reconciliation, an important medium for realizing the interaction between carbon fiber and resin matrix, and a link for load transfer between carbon fiber and resin matrix. It can achieve close bonding through similar compatibility, physical and chemical reactions, and induced crystallization, thereby improving the interface performance of composite materials.

[0004] However, due to the rigidity, non-polarity and high viscosity of PAEK molecular chains in the molten state, when used as a composite matrix, it has poor wettability and weak bonding to fibers, especially carbon fibers and aramid fibers with extremely low surface activity. The surface shows that their interlaminar shear strength (ILSS) and bending strength are low. When subjected to a moment perpendicular to the panel, the material is prone to delamination or other forms of damage and destruction. The fiber surface needs to be modified to solve the problem of poor bonding and improve the interlaminar shear strength and other properties of the composite material. It is known that activation modification is to introduce active groups on the fiber surface, create and increase the number of chemical bonds between the fiber and the polymer matrix, and improve the interfacial bonding strength and shear strength of the composite material through interaction forces. Sizing modification is to attach a thin layer of polymer to the fiber surface through a solution or emulsion coating, and use its ability to interact strongly with both the fiber and the matrix at the same time to enhance the strength of the connection between the two.

[0005] Existing activation technologies include electrodeposition treatment, strong acid treatment and ozone treatment. Considering the generation of as many active groups as possible, such as hydroxyl and carboxyl groups, on the fiber surface, and as many grooves as possible to increase the contact area with the matrix, thereby improving the mechanical strength of the composite material; however, the activation process of these methods will greatly reduce the strength of the fiber monofilaments, and at the same time have a greater impact on the environment, and can only be carried out in the laboratory and cannot be used industrially. Existing activation technologies include microwave ultrasonic co-treatment, microwave radiation and ultraviolet irradiation. The strength of the fiber monofilaments is greatly damaged, and the degree of damage is difficult to control. At the same time, these methods can only be carried out in the laboratory and cannot be used industrially. The reaction rate of reactive sizing agents (surface grafting, coupling agents, etc.) is low, and they need to be used together with the previous activation technologies. Coating sizing agents such as PEI, PI, PAA, SPEEK, etc., all create chemical bonds and hydrogen bonds between the fiber and the resin, and rely on weaker van der Waals forces to improve the wettability of the matrix to the fiber, but the effect of improving the interface interaction is limited. Summary of the invention

[0006] In order to solve the above technical problems, a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape and a preparation method thereof are provided. The present invention uses polyetheretherketoneimine polymer (PEEKI) as the main material of the sizing agent to enhance the bonding force between the fiber and the matrix, and the obtained unidirectional prepreg tape has good mechanical properties.

[0007] In order to achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] A method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape comprises the following steps:

[0009] S1, the continuous fiber is desized and then immersed in a sizing agent, dried, cooled and rolled up to obtain active fiber for standby use;

[0010] The sizing resin in the sizing agent is a polyetheretherketoneimine polymer, which is abbreviated as PEEKI and has the following chemical structure:

[0011]

[0012] S2, subjecting the active fibers to adsorption treatment in a PAEK prepreg solution, and after prepreg extrusion and shaping, cutting and rolling are performed to obtain a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape.

[0013] Furthermore, the number average molecular weight of the polyetheretherketimine polymer is in the range of 22,000 g / mol-56,000 g / mol, and the PDI is in the range of 2.2-2.8.

[0014] Furthermore, the sizing agent comprises the following materials in 100% by weight: 15%-60% polyetheretherketoneimine polymer, 3%-10% hydroxylated carbon nanotubes, 3%-15% hydroxyapatite, 1%-3% surfactant, 0.5%-1% lubricant, and the balance is organic solvent.

[0015] Furthermore, the surfactant is selected from one or more of sodium dodecyl sulfate, perfluorooctanoic acid or its esters; the lubricant is selected from one or more of silicone powder, stearic acid, zinc stearate, magnesium stearate, and calcium stearate; the organic solvent is selected from one or more of tetrahydrofuran (THF), acetone (AC), ethyl acetate, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), and N-methylpyrrolidone (NMP).

[0016] Furthermore, the polyetheretherketoneimine polymer is prepared by polycondensation reaction of N-(bis(4-fluorophenyl)methylene)aniline and hydroquinone, which specifically comprises the following steps:

[0017] At room temperature, N-(bis(4-fluorophenyl)methylene)aniline, hydroquinone, salt-forming agent, cyclopentane, and water-carrying agent are added in sequence, and stirred and heated to reflux for 80-100 minutes at a temperature of 120-150°C and high-purity nitrogen. The water generated in the reaction process will be removed during the reflux reaction; the temperature is continued to rise to 160-220°C for polymerization, and the polymerization reaction is continued for 4-8 hours under continuous stirring; then the temperature is lowered to 90-100°C while continuously stirring to obtain a viscous mixed liquid, which is cooled, poured into a poor solvent for precipitation, washed, filtered, and dried to obtain the product polyetheretherketoneimine polymer. The chemical structures of PEEKI and PAEK are highly similar, and the two are extremely compatible; the active imine group is embedded in the main chain of the PEEK molecule through the N-(bis(4-fluorophenyl)methylene)aniline monomer to improve the surface activity of the PAEK resin.

[0018] Preferably, the salt-forming agent is anhydrous sodium carbonate and / or anhydrous potassium carbonate;

[0019] The water-carrying agent is selected from one of benzene, toluene, xylene and ethylbenzene;

[0020] The poor solvent is selected from one or more of methanol, ethanol and pure water;

[0021] The molar ratio of the N-(bis(4-fluorophenyl)methylene)aniline to the hydroquinone is 1-1.2:1;

[0022] The amount of the salt-forming agent is 1-1.2 times the molar amount of the hydroquinone;

[0023] The total weight of the hydroquinone and the N-(bis(4-fluorophenyl)methylene)aniline is 25%-35% of the weight of the sulfolane;

[0024] The dosage of the water-carrying agent is 15%-30% of the weight of the sulfolane.

[0025] Furthermore, the PAEK prepreg solution includes the following materials in 100% by weight: PAEK 50%-70%, graphene oxide 5%-15%, hydroxyapatite 5%-15%, barium sulfate 5%-15%, surfactant 1%-5%, and the balance is deionized water.

[0026] Further, the surfactant is selected from one or more of fatty alcohol polyoxyethylene ether, sodium lauryl sulfate, and perfluorooctanoate;

[0027] The PAEK is selected from one or more of polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyetherketone (PEK), and polyetheretherketoneketone (PEEKK);

[0028] The continuous fiber is selected from one of high-strength carbon fiber, glass fiber and basalt fiber.

[0029] Furthermore, step S1 is completed in a sizing treatment device; and step S2 is completed in a prepreg-molding device.

[0030] Preferably, the sizing treatment equipment is sequentially connected according to the material processing direction: a first yarn placing frame, a first high-temperature drying channel, a sizing tank, a second high-temperature drying channel, and a first yarn collecting frame;

[0031] The first yarn unwinding frame and the first yarn rewinding frame use multiple bundles of the continuous fiber yarn to unwind and rewind simultaneously, and pass through multiple tension rollers at different heights to unfold each bundle of yarn and evenly adjust the surface tension, and the unwinding and rewinding speeds are controlled to be 1m / min-5m / min;

[0032] The first high-temperature drying tunnel is a semi-enclosed drying tunnel high-temperature sintering furnace, with openings at both ends for easy access of fibers, and heating on the upper and lower surfaces. A three-stage sintering furnace is provided, and the original thermosetting sizing agent on the fiber surface can be effectively removed by high-temperature decomposition and keeping the fiber in a high-temperature environment for 5-10 minutes; the three-stage temperature settings of the three-stage sintering furnace are as follows: the temperature of the first stage sintering furnace is set at 200°C-240°C, which is conducive to preheating of the fiber, and the original sizing agent begins to decompose and volatilize in small amounts; the temperature of the second stage sintering furnace is set at 280°C-320°C, which can decompose the original sizing agent in large quantities. De-volatilization; The temperature of the third section sintering furnace is set at 380℃-410℃. By increasing the temperature, the original sizing agent remaining on the fiber surface is further removed. At the same time, the length of the drying tunnel is significantly shortened compared to the other two sections. Shortening the high temperature time is conducive to inhibiting the oxidation reaction on the fiber surface and reducing the adverse effects on the fiber strength. These thermosetting sizing agents are necessary processes for fiber production. Otherwise, fuzz will be generated when the fiber is wound, and the fiber will be broken in severe cases, affecting the mechanical strength. If this type of sizing agent is not removed, it will affect the effect and quality of the composite with PAEK. Because this type of sizing agent will decompose and form gas tar volatilization in the high temperature environment of composite molding, it will hinder the wetting connection between the PAEK melt and the fiber and form shrinkage holes, reducing the mechanical strength of the strip;

[0033] A high-pressure suction fan is provided above the three-stage sintering furnace. The power of the high-pressure suction fan is 6kw, which can generate a pressure difference suction of 0.5-2KPa, and can timely and effectively discharge the decomposed volatiles. Under appropriate processing temperature and negative pressure environment, it is beneficial to improve the desizing effect and inhibit the oxidation damage of the fiber surface, and reduce the impact on the fiber strength;

[0034] The sizing agent is placed in the sizing tank, and the continuous fiber treated by the first high-temperature drying channel is immersed in the sizing agent for immersion treatment. The immersion time is controlled to be 5-10 minutes, so that a layer of sizing agent can be attached to the surface of the fiber monofilament, and the fiber monofilament and PAEK resin can be fully grasped in the subsequent pre-impregnation process, playing a bridge role; at the same time, 1-3 spiral stirring rollers are arranged in the sizing tank, and the continuous fiber is stirred evenly during the impregnation process, so as to ensure that solid materials such as hydroxyapatite in the sizing agent will not settle, thereby improving the fiber immersion adsorption quality;

[0035] The second high-temperature drying tunnel is a semi-enclosed drying tunnel high-temperature sintering furnace, the temperature of which is set at 120°C-160°C and the treatment time is 1-3 minutes, which can effectively remove moisture, organic solvents and other substances in the fiber material.

[0036] Preferably, the prepreg-molding equipment is sequentially connected according to the material processing direction: a second yarn unwinding frame, a yarn spreading roller group, a prepreg liquid tank, a third high-temperature drying tunnel, an impregnation and shaping mold, an online thickness measuring instrument, a cutting machine, and a second winding frame;

[0037] The second yarn unwinding frame adopts two sets of back-to-back structure design and single-row structure layout. Each spindle position is equipped with a servo tension control system. Through the control of the tension roller, multiple bundles can be uniformly transported forward at the same time, and a yarn collecting surface is formed to unwind the fiber yarn in parallel.

[0038] The yarn spreading roller group is composed of a plurality of yarn spreading rollers of different heights, and each bundle of fiber yarn is spread out and evenly arranged into a plane under the resonance effect of the vibration roller combination;

[0039] The PAEK pre-dip liquid is placed in the pre-dip liquid tank, and the PAEK pre-dip liquid is introduced into the pre-dip liquid tank through a mixing high-pressure pump tank. A spiral stirring roller and an online concentration measuring instrument are arranged in the pre-dip liquid tank. The prepreg of polyaryletherketone (PAEK) is placed in a tank, and the active fiber absorbs a large amount of polyaryletherketone (PAEK) slurry through immersion and adsorption. At the same time, a plurality of rollers of different heights are arranged in the tank, and the immersion and adsorption time of the prepreg and the residual amount of the prepreg on the active fiber are increased by the roller conveying of the active fiber, so as to control the content of PAEK resin in the unidirectional prepreg tape to a certain extent; 1-3 spiral stirring rollers are arranged in the tank, and the prepreg is evenly stirred during the immersion of the continuous fiber to ensure that the solid materials such as PAEK resin, hydroxyapatite (HA) powder, and barium sulfate powder in the prepreg do not settle, so as to improve the immersion and adsorption quality of the continuous fiber; the concentration in the prepreg tank is measured by an online concentration measuring instrument, and when the concentration decreases, new prepreg is injected into the prepreg tank through a mixing high-pressure pump tank to increase the concentration in the prepreg tank;

[0040] The third high-temperature drying tunnel is a semi-enclosed drying tunnel type high-temperature sintering furnace, with openings at both ends for easy access of fibers, and heating on both the upper and lower surfaces. A two-stage sintering furnace is provided, and the two-stage temperatures of the two-stage sintering furnace are set as follows: the first stage temperature is set at 120°C-150°C, which can quickly remove the moisture adsorbed in the fibers; the second stage temperature is set at 280°C-340°C, which can preheat the PAEK resin in the fibers;

[0041] The impregnation and shaping mold includes a wave-shaped impregnation section and a shaping extrusion section according to the processing direction. The upper and lower templates are used, and the spacing between the upper and lower templates is controlled by a cylinder to control the thickness of the product; the temperature of the wave-shaped impregnation section is set to 380°C-410°C, and the preheated fiber entering the mold is heated again to make the PAEK resin into a high-fluidity melt. Under the upper and lower extrusion action of the wave-shaped die teeth, the active fiber strip is impregnated with PAEK resin, hydroxyapatite (HA) powder, and barium sulfate powder, and the monofilament fiber is wrapped; the shaping extrusion section realizes the shaping and cooling of the product through three-stage stepped temperature settings, and the three-stage stepped temperature settings are 330°C-350°C, 260°C-290°C, and 130°C-160°C according to the processing direction, wherein the 260°C-290°C section allows the PAEK resin to crystallize quickly at this temperature, thereby improving the mechanical strength of the product;

[0042] The online thickness measuring instrument can accurately measure the thickness of the strip after impregnation and shaping to verify the spacing between templates and reflect the uniformity of the prepreg resin;

[0043] The cutting machine can cut and remove abnormal parts on both sides of the prepreg tape, and can also cut the prepreg tape transversely;

[0044] The second winding frame adopts a single-arm structure and is equipped with 4 winding shafts, which can perform fast and smooth winding switching of multiple rolls; at the same time, it is equipped with a tension correction device, which can achieve uniform and stable winding and winding.

[0045] Another aspect of the present invention provides a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape obtained by the above preparation method, comprising the following materials in 100% by weight: PAEK 35%-45%, hydroxyapatite 3.5%-4.5%, hydroxylated carbon nanotubes 0.5%-1.5%, graphene oxide 0.5%-1.5%, barium sulfate 6%-10%, and the balance being active fibers;

[0046] The active fibers are obtained by desizing continuous fibers and then resizing them. The sizing agent used for resizing includes the following materials in a 100% weight percentage: 15%-60% polyetheretherketoneimine polymer, 3%-10% hydroxylated carbon nanotubes, 3%-15% hydroxyapatite, 1%-3% surfactant, 0.5%-1% lubricant, and the balance is organic solvent; the sizing rate of the sizing agent is in the range of 5wt%-30wt%.

[0047] Beneficial technical effects:

[0048] The present invention adopts polyetheretherketoneimine polymer as the main material of the thermoplastic sizing agent, and embeds active imine groups on the main chain of PEEK molecules to improve the surface activity of the fiber and enhance the bonding force between the fiber and the matrix;

[0049] At the same time, special fiber sizing treatment equipment is used to effectively remove the original sizing agent remaining on the fiber surface, and at the same time, a layer of attached wrapping layer is formed on the surface of the fiber monofilament, which improves the connection strength between the fiber and the PAEK resin; through the two processes of sizing and pre-impregnation, functional materials such as hydroxyapatite and barium sulfate are efficiently and accurately wrapped in the interface between the fiber and the PAEK resin, which improves the medical biocompatibility and radiographic effect of the continuous fiber reinforced PAEK unidirectional prepreg tape; the use of special sizing treatment equipment and special pre-impregnation-molding equipment realizes efficient processing of fiber materials and precise control of prepreg tapes, improving production efficiency and product quality;

[0050] The unidirectional prepreg tape prepared by the method of the present invention has excellent mechanical properties, with a tensile strength of more than 3000 MPa, a bending strength of more than 2800 MPa, a compressive strength of more than 1500 MPa, an interlaminar shear strength of more than 130 MPa, and a longitudinal and transverse shear strength of 150 MPa. The improvement of these properties makes the material more suitable for use in the fields of medical implants.

[0051] The method of the invention avoids the problems of great environmental impact and difficulty in industrialization in the prior art, improves the preparation efficiency of the main material of the thermoplastic sizing agent, and reduces resource waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a structural schematic diagram of sizing processing equipment;

[0053] Figure 2 It is a schematic diagram of the structure of the prepreg-molding equipment. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present invention will be described clearly and completely below in combination with the embodiments of the present invention and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. All other embodiments obtained by ordinary technicians in this field without creative work based on the embodiments of the present invention are within the scope of protection of the present invention.

[0055] Unless otherwise specifically stated, the numerical value set forth in these embodiments does not limit the scope of the present invention. The technology and method known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology and method should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values.

[0056] In addition, it should be noted that the use of terms such as "first" and "second" to limit each component is only for the convenience of distinguishing the components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0057] The experimental methods in the following examples without specifying specific conditions are usually measured in accordance with national standards; if there is no corresponding national standard, the method is carried out in accordance with the general standard requirements or general methods.

[0058] Preparation Example 1

[0059] The present invention is the preparation of polyetheretherketoneimine polymer PEEKI, which has the following chemical structure:

[0060]

[0061] The product is prepared by polycondensation reaction of N-(bis(4-fluorophenyl)methylene)aniline (CAS: 109997-74-2) and hydroquinone, which specifically comprises the following steps:

[0062] At room temperature, N-(bis(4-fluorophenyl)methylene)aniline (C 19 H 12 NF2, represented by "nitrogen-containing raw material" in Table 1 below), hydroquinone, anhydrous sodium carbonate, cyclopentane, and p-xylene are stirred and heated to reflux for 80-100 minutes at a temperature of 120-150°C and high-purity nitrogen, and the water generated in the reaction process will be removed during the reflux reaction; the temperature is continued to be raised to 160-220°C for polymerization, and the polymerization reaction is continued for 4-8 hours under continuous stirring; then the temperature is lowered to 90-100°C while continuously stirring to obtain a viscous mixed solution, which is cooled and poured into a mixed solution of methanol and water (the volume ratio of methanol to water is 1:2) to precipitate a polymer, and the polymer is washed alternately with hot pure water for multiple times, and then filtered and dried to obtain the product polyetheretherketoneimine polymer PEEKI. The specific reaction conditions are shown in Table 1 below.

[0063] Table 1 Polyetheretherketoneimine polymer reaction conditions

[0064]

[0065] Preparation Example 2

[0066] This case is the configuration of sizing agent, and the formula is shown in Table 2 below.

[0067] Table 2 Sizing agent formula

[0068]

[0069] Preparation Example 3

[0070] This case is the configuration of PAEK prepreg, and the formula is shown in Table 3 below.

[0071] Table 3 PAEK prepreg formula

[0072]

[0073]

[0074] Example 1

[0075] A method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape comprises the following steps:

[0076] S1, continuous carbon fiber (model SYT55S) enters the sizing treatment equipment for desizing treatment and then immerses in the sizing agent ① for impregnation treatment, and then cools and rolls up after drying to obtain active fiber for standby use;

[0077] The sizing treatment equipment is as follows Figure 1 As shown, according to the material processing direction, the following are connected in sequence: a first yarn placing frame, a first high-temperature drying channel, a sizing trough, a second high-temperature drying channel, and a first yarn collecting frame;

[0078] The first yarn unwinding frame and the first yarn rewinding frame use multiple bundles of the continuous fiber yarn to unwind and rewind simultaneously, and pass through multiple tension rollers at different heights to unfold each bundle of yarn and evenly adjust the surface tension, and the unwinding and rewinding speed is controlled to be 2m / min;

[0079] The first high-temperature drying tunnel is a semi-enclosed drying tunnel type high-temperature sintering furnace, with openings at both ends for easy access of fibers, and heating on the upper and lower surfaces. A three-stage sintering furnace is provided, and the three-stage temperatures of the three-stage sintering furnace are set as follows: the temperature of the first stage sintering furnace is set to 200°C (the drying tunnel length of the sintering furnace is 900mm), which is conducive to preheating of the fibers, and the original sizing agent begins to decompose and volatilize in small amounts; the temperature of the second stage sintering furnace is set to 300°C (the drying tunnel length of the sintering furnace is 1500mm), which can decompose and volatilize the original sizing agent in large quantities; the temperature of the third stage sintering furnace is set to 410°C (the drying tunnel length of the sintering furnace is 500mm), and the original sizing agent remaining on the fiber surface is removed by increasing the temperature. The agent is further removed cleanly, and the length of the drying tunnel is significantly shortened compared with the other two sections. Shortening the high temperature time is conducive to inhibiting the oxidation reaction on the fiber surface and reducing the adverse effect on the fiber strength. The overall high temperature decomposition treatment time is within the range of 5-10 minutes, which can effectively remove the original thermosetting sizing agent on the fiber surface; a high-pressure suction fan is provided above the three-stage sintering furnace. The power of the high-pressure suction fan is 6kw, which can generate a pressure difference suction of at least 0.5KPa, and the decomposed volatiles are discharged in a timely and effective manner. Under appropriate treatment temperature and negative pressure environment, it is conducive to improving the desizing treatment effect and inhibiting the oxidation damage of the fiber surface, and reducing the impact on the fiber strength;

[0080] The sizing agent ① is placed in the sizing tank, and the continuous fibers treated by the first high-temperature drying channel are immersed in the sizing agent ① for immersion treatment, and the immersion time is controlled within the range of 5-10 minutes; at the same time, three spiral stirring rollers are arranged in the sizing tank to uniformly stir the continuous fibers during the immersion process;

[0081] The second high-temperature drying tunnel is a semi-enclosed drying tunnel high-temperature sintering furnace, the temperature is set to 150°C, and the processing time is 1-3 minutes;

[0082] Taking the processing of 10kg of continuous carbon fiber as an example, after the first high-temperature drying channel in step S1, 9kg of desizing fiber is obtained, and then after sizing and drying, 9.65kg of active fiber is obtained;

[0083] S2, subjecting the active fibers to adsorption treatment through a prepreg-molding device, and after prepreg extrusion and shaping, cutting and rolling to obtain a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape;

[0084] The prepreg-molding equipment is as follows Figure 2 As shown, the following are connected in sequence according to the material processing direction: a second yarn unwinding frame, a yarn spreading roller group, a prepreg tank, a third high-temperature drying tunnel, an impregnation and shaping mold, an online thickness measuring instrument, a cutting machine, and a second winding frame;

[0085] The second unwinding frame adopts two sets of back-to-back structure design and single-row structure layout. Each spindle position is equipped with a servo tension control system. Through the control of the tension roller, multiple bundles can be uniformly transported forward at the same time, and a yarn collecting surface is formed to unwind the fiber yarn in parallel. The yarn unwinding rate and winding rate are the same as those of the first unwinding frame mentioned above.

[0086] The yarn spreading roller group is composed of a plurality of yarn spreading rollers of different heights, and each bundle of fiber yarn is spread out and evenly arranged into a plane under the resonance effect of the vibration roller combination;

[0087] A PAEK prepreg liquid α is placed in the prepreg liquid tank, and the PAEK prepreg liquid α is introduced into the prepreg liquid tank through a mixing high-pressure pump tank, and two spiral stirring rollers and an online concentration measuring instrument are arranged in the prepreg liquid tank;

[0088] The third high-temperature drying tunnel is a semi-enclosed drying tunnel type high-temperature sintering furnace, with openings at both ends for easy access of fibers, and heating on both the upper and lower surfaces. A two-stage sintering furnace is provided, and the two-stage temperatures of the two-stage sintering furnace are set as follows: the temperature of the first-stage sintering furnace is set at 135°C, which can quickly remove the moisture adsorbed in the fibers; the temperature of the second-stage sintering furnace is set at 320°C, which can preheat the PEEK resin in the fibers;

[0089] The impregnation and shaping mold includes a wave-shaped impregnation section and a shaping extrusion section according to the processing direction. The upper and lower templates are used, and the spacing between the upper and lower templates is controlled by a cylinder to control the thickness of the product; the temperature of the wave-shaped impregnation section is set to 400°C, and the preheated fiber entering the mold is heated again to make the PEEK resin into a high-fluidity melt. Under the upper and lower extrusion action of the wave-shaped die teeth, the active fiber strip is impregnated with PEEK resin, HA powder, and barium sulfate powder, and the monofilament fiber is wrapped; the shaping extrusion section realizes the shaping and cooling of the product through three-stage stepped temperature settings, and the three-stage stepped temperature settings are 350°C, 290°C, and 160°C according to the processing direction;

[0090] The online thickness measuring instrument accurately measures the thickness of the strip after infiltration and shaping;

[0091] The cutting machine cuts and removes abnormal parts on both sides of the prepreg tape, and also cuts the prepreg tape transversely;

[0092] The second winding frame adopts a single-arm structure and is equipped with 4 winding shafts, which can quickly and smoothly switch between multiple rolls; at the same time, it is equipped with a tension correction device, which can wind and rewind evenly and smoothly;

[0093] The final medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape (thickness 0.10 mm) includes the following materials in 100% weight percentage: PEEK 26%, hydroxyapatite 1.7%, hydroxylated carbon nanotubes 0.6%, graphene oxide 0.6%, barium sulfate 4%, and the balance is active fiber.

[0094] Example 2

[0095] A method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape comprises the following steps:

[0096] S1, continuous carbon fiber (model HF40) enters the sizing treatment equipment for desizing treatment and then immerses in the sizing agent ② for impregnation treatment, and then cools and rolls up after drying to obtain active fiber for standby use;

[0097] The sizing treatment equipment is the same as that in Example 1, and the parameters are as follows:

[0098] The unwinding and winding speeds of the first unwinding frame and the first winding frame are controlled to be 1 m / min;

[0099] The three-stage temperature settings of the three-stage sintering furnace of the first high-temperature drying tunnel are as follows: the temperature of the first stage sintering furnace is set to 220°C (the drying tunnel length of the sintering furnace is 900mm), the temperature of the second stage sintering furnace is set to 280°C (the drying tunnel length of the sintering furnace is 1500mm), and the temperature of the third stage sintering furnace is set to 380°C (the drying tunnel length of the sintering furnace is 700mm);

[0100] The sizing agent② is placed in the sizing tank;

[0101] The temperature of the second high temperature drying channel is set to 140°C;

[0102] Taking the processing of 10kg of continuous carbon fiber as an example, after the first high-temperature drying in step S1, 7.5kg of desizing fiber is obtained, and then after sizing and drying, 9.56kg of active fiber is obtained;

[0103] S2, subjecting the active fibers to adsorption treatment through a prepreg-molding device, and after prepreg extrusion and shaping, cutting and rolling to obtain a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape;

[0104] The prepreg-molding equipment is the same as that in Example 1, except that:

[0105] The yarn unwinding speed and winding speed are the same as those of the first unwinding frame mentioned above;

[0106] The PAEK prepreg liquid β is placed in the prepreg liquid tank;

[0107] The second stage temperature of the second stage sintering furnace of the third high temperature drying tunnel is set as follows: the first stage sintering furnace temperature is set to 140°C, and the second stage sintering furnace temperature is set to 300°C;

[0108] The temperature of the wave-shaped infiltration section in the infiltration and shaping mold is set to 395°C, and the three-stage stepped temperature settings of the subsequent shaping extrusion section are 330°C, 280°C, and 150°C according to the processing direction;

[0109] The final medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape has a thickness of 0.12 mm and includes the following materials in 100% weight percentage: PEEK 29%, hydroxyapatite 3.1%, hydroxylated carbon nanotubes 0.9%, graphene oxide 0.8%, barium sulfate 6%, and the balance is active fiber.

[0110] Example 3

[0111] A method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape comprises the following steps:

[0112] S1, continuous carbon fiber (model T800-12K) enters the sizing treatment equipment for desizing treatment and then is immersed in the sizing agent ③ for impregnation treatment, dried and cooled and rolled up to obtain active fiber for standby use;

[0113] The sizing treatment equipment is the same as that in Example 1, and the parameters are as follows:

[0114] The unwinding and winding speeds of the first unwinding frame and the first winding frame are controlled to be 1.4 m / min;

[0115] The three-stage temperature settings of the three-stage sintering furnace of the first high-temperature drying tunnel are as follows: the temperature of the first stage sintering furnace is set to 240°C (the drying tunnel length of the sintering furnace is 800mm), the temperature of the second stage sintering furnace is set to 320°C (the drying tunnel length of the sintering furnace is 1400mm), and the temperature of the third stage sintering furnace is set to 400°C (the drying tunnel length of the sintering furnace is 700mm);

[0116] The sizing agent is placed in the sizing tank③;

[0117] The temperature of the second high temperature drying channel is set to 160°C;

[0118] Taking the processing of 10 kg of continuous carbon fiber as an example, after the first high-temperature drying in step S1, 8.4 kg of desizing fiber is obtained, and then after sizing, 9.62 kg of active fiber is obtained;

[0119] S2, subjecting the active fibers to adsorption treatment through a prepreg-molding device, and after prepreg extrusion and shaping, cutting and rolling to obtain a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape;

[0120] The prepreg-molding equipment is the same as that in Example 1, except that:

[0121] The yarn unwinding speed and winding speed are the same as those of the first unwinding frame mentioned above;

[0122] PAEK prepreg liquid γ is placed in the prepreg liquid tank;

[0123] The second stage temperature of the second stage sintering furnace of the third high temperature drying tunnel is set as follows: the temperature of the first stage sintering furnace is set to 150° C., and the temperature of the second stage sintering furnace is set to 340° C.;

[0124] The temperature of the wave-shaped infiltration section in the infiltration and shaping mold is set to 410°C, and the three-stage stepped temperature settings of the subsequent shaping and extrusion section are 340°C, 270°C, and 140°C respectively according to the processing direction;

[0125] The final medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape has a thickness of 0.15 mm and includes the following materials in 100% weight percentage: PEEK 30%, hydroxyapatite 4%, hydroxylated carbon nanotubes 1%, graphene oxide 1%, barium sulfate 8%, and the balance is active fiber.

[0126] Comparative Example 1

[0127] The preparation process of the medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape in this case is the same as that in Example 3, except that the main resin PEEKI-Ⅰ in the sizing agent ① is replaced with PEI (US Sabic PEI 2200HF).

[0128] Comparative Example 2

[0129] The preparation process of the medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape in this case is the same as that in Example 3, except that the main resin PEEKI-Ⅰ in the sizing agent ① is replaced by TPI (Jilin Gaoqi YGM200 series).

[0130] Comparative Example 3

[0131] The preparation process of the medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape in this case is the same as that in Example 3, except that the main resin PEEKI-Ⅰ in the sizing agent ① is replaced with PES (Ultrason E2010 of BASF, Germany).

[0132] The above materials were tested for performance and the results are shown in Table 4.

[0133] Table 4 Material properties

[0134]

[0135] From Table 1, we can see that

[0136] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape, characterized in that: The steps include: S1, the continuous fiber is desized and then immersed in a sizing agent, dried, cooled and rolled up to obtain active fiber for standby use; The sizing resin in the sizing agent is a polyetheretherketoneimine polymer having the following chemical structure: S2, subjecting the active fibers to adsorption treatment in a PAEK prepreg solution, and after prepreg extrusion and shaping, cutting and rolling are performed to obtain a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape.

2. The method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape according to claim 1, characterized in that: The number average molecular weight of the polyetheretherketoneimine polymer is in the range of 22,000 g / mol-56,000 g / mol, and the PDI is in the range of 2.2-2.

8.

3. The method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape according to claim 2, characterized in that: The sizing agent comprises the following materials in 100% by weight: 15%-60% of polyetheretherketoneimine polymer, 3%-10% of hydroxylated carbon nanotubes, 3%-15% of hydroxyapatite, 1%-3% of surfactant, 0.5%-1% of lubricant, and the balance is organic solvent.

4. The method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape according to claim 3, characterized in that: The surfactant is selected from one or more of sodium dodecyl sulfate, perfluorooctanoic acid or its esters; the lubricant is selected from one or more of silicone powder, stearic acid, zinc stearate, magnesium stearate, and calcium stearate; the organic solvent is selected from one or more of tetrahydrofuran, acetone, ethyl acetate, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

5. The method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape according to any one of claims 1 to 4, characterized in that: The polyetheretherketoneimine polymer is prepared by polycondensation reaction of N-(bis(4-fluorophenyl)methylene)aniline and hydroquinone, which specifically comprises the following steps: At room temperature, N-(bis(4-fluorophenyl)methylene)aniline, hydroquinone, salt-forming agent, cyclopentane and water-carrying agent are added in sequence, and the mixture is stirred, heated and refluxed at a temperature of 120-150° C. and in high-purity nitrogen for 80-100 minutes. The water generated in the reaction process will be removed during the reflux reaction. The mixture is heated to 160-220° C. for polymerization reaction, and the polymerization reaction is continued for 4-8 hours under continuous stirring. The mixture is then cooled to 90-100° C. and continuously stirred to obtain a viscous mixed liquid, which is then cooled, poured into a poor solvent for precipitation, washed, filtered and dried to obtain a product, polyetheretherketoneimine polymer.

6. The method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape according to claim 5, characterized in that: The salt-forming agent is anhydrous sodium carbonate and / or anhydrous potassium carbonate; The water-carrying agent is selected from one of benzene, toluene, xylene and ethylbenzene; The poor solvent is selected from one or more of methanol, ethanol and pure water; The molar ratio of the N-(bis(4-fluorophenyl)methylene)aniline to the hydroquinone is 1-1.2:1; The amount of the salt-forming agent is 1-1.2 times the molar amount of the hydroquinone; The total weight of the hydroquinone and the N-(bis(4-fluorophenyl)methylene)aniline is 25%-35% of the weight of the sulfolane; The dosage of the water-carrying agent is 15%-30% of the weight of the sulfolane.

7. A method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape according to any one of claims 1 to 4, characterized in that: The PAEK pre-dip solution includes the following materials in 100% by weight: 50%-70% PAEK, 5%-15% graphene oxide, 5%-15% hydroxyapatite, 5%-15% barium sulfate, 1%-5% surfactant, and the balance is deionized water.

8. The method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape according to claim 7, characterized in that: The surfactant is selected from one or more of fatty alcohol polyoxyethylene ether, sodium lauryl sulfate, and perfluorooctanoate; The PAEK is selected from one or more of polyetheretherketone, polyetherketoneketone, polyetherketone, and polyetheretherketoneketone; The continuous fiber is selected from one of high-strength carbon fiber, glass fiber and basalt fiber.

9. The method for preparing a medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape according to any one of claims 1 to 4, characterized in that: Step S1 is completed in a sizing treatment device, which is sequentially connected according to the material processing direction and is provided with: a first yarn placing frame, a first high-temperature drying channel, a sizing trough, a second high-temperature drying channel, and a first yarn collecting frame; The first yarn unwinding frame and the first yarn rewinding frame have unwinding and rewinding speeds controlled to be 1m / min-5m / min; The first high-temperature drying tunnel is a semi-enclosed drying tunnel type high-temperature sintering furnace, with openings at both ends for easy fiber entry and exit, and upper and lower surfaces are heated. A three-stage sintering furnace is provided, and the three-stage temperatures of the three-stage sintering furnace are set as follows: the temperature of the first stage sintering furnace is set to 200°C-240°C, the temperature of the second stage sintering furnace is set to 280°C-320°C, and the temperature of the third stage sintering furnace is set to 380°C-410°C; a high-pressure suction fan is provided above the three-stage sintering furnace, and the power of the high-pressure suction fan is 6kw, generating a pressure difference suction force of 0.5-2KPa; The sizing agent is placed in the sizing tank, and the continuous fibers treated by the first high-temperature drying channel are immersed in the sizing agent for immersion treatment, and the immersion time is controlled to be 5-10 minutes. At the same time, 1-3 spiral stirring rollers are arranged in the sizing tank; The second high-temperature drying tunnel is a semi-enclosed drying tunnel high-temperature sintering furnace, the temperature is set at 120°C-160°C, and the treatment time is 1-3 minutes; Step S2 is completed in a prepreg-molding device, which is sequentially connected according to the material processing direction and is equipped with: a second yarn unwinding frame, a yarn spreading roller group, a prepreg liquid tank, a third high-temperature drying tunnel, an impregnation and shaping mold, an online thickness measuring instrument, a cutting machine, and a second winding frame; The PAEK prepreg is placed in the prepreg tank, and the PAEK prepreg is introduced into the prepreg tank through a mixing high-pressure pump tank. A spiral stirring roller and an online concentration measuring instrument are arranged in the prepreg tank, and 1-3 spiral stirring rollers are arranged in the tank; The third high-temperature drying tunnel is a semi-enclosed drying tunnel type high-temperature sintering furnace, with openings at both ends for easy access of fibers, heating on both the upper and lower sides, and a two-stage sintering furnace. The two-stage temperatures of the two-stage sintering furnace are set as follows: the first stage temperature is set at 120°C-150°C, and the second stage temperature is set at 280°C-340°C; The infiltration and shaping mold includes a wave-shaped infiltration section and a shaping extrusion section according to the processing direction. The upper and lower templates are used, and the spacing between the upper and lower templates is controlled by a cylinder to control the thickness of the product; the temperature of the wave-shaped infiltration section is set to 380°C-410°C; the shaping extrusion section realizes the shaping and cooling of the product through three-stage stepped temperature settings, and the three-stage stepped temperature settings are 330°C-350°C, 260°C-290°C, and 130°C-160°C according to the processing direction.

10. The medical high-strength continuous fiber reinforced PAEK unidirectional prepreg tape obtained by the preparation method according to any one of claims 1 to 9, characterized in that: The invention comprises the following materials in an amount of 100% by weight: 35%-45% of PAEK, 3.5%-4.5% of hydroxyapatite, 0.5%-1.5% of hydroxylated carbon nanotubes, 0.5%-1.5% of graphene oxide, 6%-10% of barium sulfate, and the balance is active fiber; The active fibers are obtained by desizing continuous fibers and then resizing them. The sizing agent used for resizing includes the following materials in a 100% weight percentage: 15%-60% polyetheretherketoneimine polymer, 3%-10% hydroxylated carbon nanotubes, 3%-15% hydroxyapatite, 1%-3% surfactant, 0.5%-1% lubricant, and the balance is organic solvent; the sizing rate of the sizing agent is in the range of 5wt%-30wt%.

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