Catheter liner comprising or consisting of polyaryletherketone

Abstract

The present invention relates to a liner for medical catheters, wherein the liner comprises or consists of polyaryletherketone, in particular in the form of polyether ether ketone or sulfonated polyether ether ketone. By forming the liner from polyaryletherketone, sliding properties comparable to PTFE can be provided in the interior of the liner.

Description

[0001] Catheter liner comprising or consisting of polyaryletherketone

[0002] Description

[0003] All documents cited in the present application are incorporated by reference in their entirety into the present disclosure.

[0004] The present invention relates to a liner for medical catheters, wherein the liner comprises or consists of polyaryletherketone.

[0005] State of the art:

[0006] A liner forms the innermost layer of the catheter tube in a medical catheter and must therefore meet various requirements during use. For example, the liner must be highly flexible and have low rigidity so that the catheter can be guided to a desired position in the body, which is usually achieved via blood vessels. Another relevant property for liners is the wall thickness, which should be as small as possible so that the catheter can have the largest possible inner lumen and a small outer diameter. Another important property for catheter liners is a low coefficient of friction of the material, as catheters are typically used to insert tools through the catheter tube or to transport fluids, where high frictional resistance is associated with obvious disadvantages.

[0007] Accordingly, materials and processes must be selected for the production of catheter liners that enable the above-mentioned properties to be realized.

[0008] Due to the now well-known problem of the high environmental stability of poly- or perfluorinated alkyl substances (PFAS), a ban on these substances is being discussed in the EU and the USA. PFAS, and in particular polytetrafluoroethylene (PTFE), are materials used in the manufacture of liners for medical catheters due to their properties and are currently irreplaceable. PTFE is used in this field primarily due to its excellent sliding properties and the softness of the plastic. Since no other material with comparable properties is known in this area, PTFE is difficult to replace for liner production based on the current state of the art.

[0009] EP 3 769 937 A1 discloses a process for producing catheter liners based on the use of polytetrafluoroethylene. Further prior art dealing with the use of perfluoropolymers, particularly in the form of tetrafluoroethylene-hexafluoropropylene copolymer, as liner material for catheters includes, for example, EP 0 530 201 B1.

[0010] Due to the environmental aspects that have become more relevant in recent years, possibilities are being sought to avoid the use of problematic poly- or perfluorinated alkyl substances (PFAS), in particular PTFE, in the production of liners for medical catheters and in liners for medical catheters, although with regard to the properties desired for the liners compared to PTFE, no deterioration should be accepted if possible.

[0011] The object of the present invention was therefore to propose, in view of the state of the art, an alternative to the poly- or perfluorinated alkyl substances (PFAS), in particular PTFE, previously used as liner material, whereby liners for medical catheters with good property profiles are to be obtained.

[0012] Further tasks for the specialist arise from the following description.

[0013] These and other objects are achieved within the scope of the present invention by the subject matter of the independent claims. Preferred embodiments emerge from the dependent claims and the following description.

[0014] Within the scope of the present invention, the term "comprise" also includes, as a particularly preferred embodiment, "consisting of"; this means that a corresponding list may contain (=comprise) further elements in addition to the explicitly mentioned elements, or it may contain precisely these elements (=consist of). If the wording "comprise" is used below, an analogous embodiment is also disclosed that is formed only from the mentioned elements (i.e., "consists" of them), even if these are not explicitly stated below for reasons of brevity.

[0015] In the context of the present invention, the term "and / or" means that both elements mentioned in the context are included individually as well as the combination of the elements mentioned in the context.

[0016] In the context of the present invention, all quantities are to be understood as weights unless otherwise stated.

[0017] The present invention relates in a first aspect to a liner for medical catheters, wherein the liner comprises or consists of polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK).

[0018] If the liner comprises or consists of sulfonated polyetheretherketone, this preferably has a degree of sulfonation in the range from 40 to 100%, wherein the degree of sulfonation is in particular more than 50%, more preferably more than 60%, even more preferably more than 70%, even more preferably more than 80%, and even more preferably more than 90%. The degree of sulfonation SD can be determined by titration with NaOH, wherein first the ion exchange capacity (IEC) is determined according to the formula

[0019] Voters wn KaOff x Concentration of ItfaOH IEC = -

[0020] Weight of the svlfomerted PEEK and then from this using the formula

[0021] M"xIEC

[0022] SD = - - - 1000 — (M JO3IB X IEC) the degree of sulfonation SD is determined, where M P = 288 g mol' 1 and MSOSH = 80 g mol' 1 are the molecular weights of the monomer units of the polymer and the sulfonic acid groups (as an average of a triplicate determination).

[0023] A suitable molecular weight Mw of polyaryletherketone, and in particular of polyetheretherketone in non-sulfonated or sulfonated form, is advantageously in the range from 5,000 to 100,000 g / mol, with a range from 10,000 to 80,000 g / mol, in particular from 15,000 to 60,000 g / mol, and more particularly from 20,000 to 40,000 g / mol being particularly suitable. The molecular weight here refers to the weight-average molecular weight Mw and is determined for the specified ranges by GPC and comparison with suitable standards (e.g., polystyrene).

[0024] In other words, this subject matter of the present invention relates to a liner for a catheter formed from a new material, which encloses the inner lumen of the catheter in a corresponding catheter.

[0025] In a preferred embodiment, the liner according to the invention is formed from fibers produced by electrospinning, and in particular is completely spun.

[0026] In preferred variants, the liner according to the invention comprises at least one electrospun fiber layer whose fibers have a uniform orientation, preferably an orientation in an angular range between 0° and 90°, particularly preferably angles of ±45° or 90°, in each case relative to the longitudinal axis of the liner. "Uniform" is understood here to mean that the fibers (at least in one fiber layer) are aligned substantially parallel.

[0027] This has the advantage that various properties of the liner, such as axial stiffness, strength, and / or elongation, can be adjusted to a desired level. In this case, the liner's properties are anisotropic, meaning they are directionally dependent. Furthermore, by appropriately aligning the fibers, the catheter's torque transmission can be increased.

[0028] Alternatively, the fibers of the at least one electrospun fiber layer can be randomly aligned. In this case, the properties of the liner are isotropic, i.e., direction-independent. This allows residual elongation to be maintained in the liner material, so that the liner has high flexibility and elongation. In this case, the elongation of the liner can be further adjusted, for example, by braiding the liner with wires. Furthermore, alignment of the randomly arranged electrospun fibers or those manufactured as a nonwoven can be achieved by post-treatment of the liner. For example, fiber alignment can be induced by post-drawing or stretching the liner, which allows adjustment of the elongation and / or strength.

[0029] In further preferred variants of the present invention, the liner comprises a plurality of electrospun fiber layers whose fibers are aligned identically or differently, either i) - at an angle of +45° with respect to the longitudinal axis of the liner, or ii) - at an angle of -45° with respect to the longitudinal axis of the liner, or iii) - at an angle of +90° with respect to the longitudinal axis of the liner, or iv) - a combination of variants i), ii), iii), or v) - a combination of variants i) and ii), or vi) - randomized.

[0030] The longitudinal axis of the liner refers to the direction of longitudinal expansion of the liner tube. During liner production, this is determined by the longitudinal expansion of a mandrel onto which the liner material is applied to form the liner. The longitudinal expansion refers to the spatial direction orthogonal to the round cross-section of the mandrel.

[0031] In yet further preferred variants of the present invention, the liner has a wall thickness of 1 pm to 100 pm, in particular of 2 pm to 50 pm, in particular of 3 pm to 40 pm, more preferably of 4 pm to 30 pm, and even more preferably of 5 pm to 25 pm. Due to these comparatively small wall thicknesses, the liner has good flexibility, which is particularly advantageous for use in microcatheter systems. Another advantage of the material forming the liner, polyaryletherketone, is that it has material properties that allow the production of stable liners with such small thicknesses. In yet further preferred variants of the present invention, the liner has an inner diameter of 50 pm to 5000 pm, in particular of 100 pm to 4000 pm, in particular of 200 pm to 3000 pm, in particular of 300 pm to 2250 pm.This comparatively small inner diameter of the liner allows for use in microcatheter systems. Furthermore, the outer diameter of the liner can be advantageously adapted to the inner diameter of the catheter or is dependent on it.

[0032] The length of the finished tubular liner in the axial direction can be at least 1 cm, in particular at least 5 cm, in particular at least 10 cm. In most cases, the liner will have a length of no more than 2 m, as such a length is sufficient for most applications in which a catheter is used. The liner can extend over the entire length of the catheter. Alternatively, it is possible for the electrospun liner to be limited to sections of the catheter. Between the electrospun sections, the catheter can be free of a liner or have liners made of a different material.

[0033] In further preferred variants of the present invention, in addition to the polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK), at least one further polymer is selected from the group consisting of fluorinated polymers (e.g. PTFE, polyvinylidene fluoride - PVDF), polyolefins (e.g. PP, PE), polyurethanes (e.g. thermoplastic polyurethanes (TPU), or hydrophilic polyurethanes), polyamides (e.g. PA6.6), polyetherblockamides (PEBA), polyesters (e.g. PLA, PLGA, PET), polysulfones (e.g.PSU), biological polymers, protein-based polymers or mixtures thereof, are included in the liner according to the invention, wherein the further polymer is preferably selected from the group consisting of polyolefins, polyurethanes, polyamides, polyesters, polysulfones and mixtures thereof; in particular selected from the group consisting of polypropylenes (PP), polyethylenes (PE), thermoplastic polyurethanes (TPU), hydrophilic polyurethanes, polyether block amides (PEBA), polyamide 6.6 (PA 6.6), polyamide 6.12 (PA 6.12), polylactic acids (PLA), poly(lactide-co-glycolide) (PLGA), polyethylene terephthalate (PET), polysulfone (PSU) and mixtures thereof; and most preferably selected from the group consisting of polypropylenes, polyethylenes, polyether block amides (PEBA), polyamide 6.6, polyamide 6.12, polylactic acids, poly(lactide-co-glycolide), polyethylene terephthalate, polysulfone and mixtures thereof.Since, as mentioned above, the aim of the present invention is, among other things, to minimize the use of fluorinated polymers in the liner material, it is preferred if exclusively non-poly- or perfluorinated polymers are used as further polymers.

[0034] The additional polymers are used in particular in embodiments in which multiple layers of fibers or plies are used to construct the liner. This is because it is conceivable, and encompassed by the present invention, that different layers of the liner are formed from different polymers. In other words, the electrospun fibers or plies of the liner can be formed from or consist of different polymers. Additional liner layers formed from another polymer are preferably applied to the outer side of a liner layer formed from the polyaryletherketone, and in particular from polyetheretherketone or sulfonated polyetheretherketone.

[0035] Furthermore, filaments can be inserted between the electrospun fiber layers of the liner. For example, the filaments can be made of or consist of a radiopaque material such as tungsten or bismuth. This gives the catheter good radiopacity. Alternatively or additionally, the filaments can be made of a rigid material. In this case, the filaments can be inserted in the longitudinal direction of the liner to increase the flexural rigidity of the liner in the longitudinal direction. For example, the filaments can be made of aramids, polyethylene, and / or other polymers. Furthermore, nickel-titanium wires, stainless steel wires, and / or wires made of another metallic material can be inserted between the fiber layers. The filaments can therefore influence the mechanical properties of the liner.

[0036] The sPEEK, which is particularly preferred for use in the present invention, can, in principle, be produced in any desired manner. A preferred variant is the treatment of PEEK with sulfuric acid or chlorosulfonic acid, for example, the reaction of PEEK with chlorosulfonic acid in dimethylformamide at 80°C. However, there are also other production variants that lead to sPEEK that can be used according to the invention. In principle, any sPEEK can be used in the present invention, regardless of the precise production method.

[0037] In principle, liners made of polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), especially sulfonated polyetheretherketone (sPEEK), can be produced conventionally by extruding thin tubes or by producing films by flat extrusion or casting, which are then wound around a mandrel and stabilized. The latter can be achieved, for example, by annealing, sintering, chemically (e.g., crosslinking), and / or by physical crosslinking. These stabilization steps are commonly known and readily understood by those skilled in the art. This type of production is a preferred variant of the present invention.

[0038] In preferred variants of the present invention, the materials are extruded from the dissolved or dispersed polymer, whereby the polymer solution or dispersion is extruded and the solvent is subsequently evaporated (sol-gel process). This has the advantage, particularly with sPEEK, which is highly preferred as a liner material, that processing can take place at lower temperatures and the cleavage of sulfonic acid groups, which occurs at temperatures of 250 to 280 °C, is avoided.

[0039] In principle, however, in other preferred variants of the present invention, processing from the melt is also possible if a suitable process window is selected for this purpose. For example, it is conceivable that the PEEK, after being processed into films, is treated with sulfuric acid or another sulfonating agent in order to generate sulfonic acid groups (sPEEK) on the surface of the film. The film can then be wound onto a mandrel such that the surface treated with the sulfonating agent comes into contact with the surface of the mandrel. Another method according to the invention, thus another preferred variant, for producing the liners is by means of electrospinning from an sPEEK solution. Here, the sPEEK fibers are deposited on a non-stick coated rod collector or mandrel collector with a defined diameter, forming a tubular structure.The mechanical properties of the tubular liner can be influenced by adjusting the fiber deposition on the mandrel.

[0040] By means of a randomized fiber deposition, a residual elongation in the material can be obtained, among other things, so that liners produced in this way have a high flexibility as well as axial and longitudinal elongation and thus represent preferred variants of the present invention.

[0041] In preferred variants of the present invention, the extensibility of the products can be further improved and, in particular, adjusted precisely to the desired level by additional suitable stabilizing deposits / layers at multiple angles, or, for example, by winding a coil or braiding the liner with wires.

[0042] By placing the fibers in a structured manner at an angle of, for example, ± 45° or 90° to the mandrel axis, the axial stiffness and longitudinal residual strain of the liner can be adjusted. The thickness of the liner is adjustable based on the number of applied fiber layers.

[0043] Alternatively, the liner material can also be produced in a flat, continuous electrospinning process. A liner can then be manufactured from the nonwovens produced in this way by winding the nonwovens onto a mandrel. The wall thickness of the liner can be adjusted via the thickness of the nonwoven layer or the number of nonwoven layers. Finally, the liner must be consolidated in a further processing step, e.g. by tempering, sintering, chemically (e.g. crosslinking) and / or by physical crosslinking, whereby these consolidation steps are conventionally known and readily understood by the person skilled in the art. The fiber deposition in this process can be either randomized or aligned in one direction (structured). The present invention therefore also relates to methods for producing a liner for medical catheters according to the present invention.

[0044] In a first variant, such a method according to the invention comprises producing an inner liner material layer by extruding a tube from the liner material, and optionally applying additional liner material layers to the outer side of the inner liner material layer. The liner material used is polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK). Preferably, no poly- or perfluorinated alkyl substances are incorporated into the liner during the process.As described above, the material from which the liner material layer is formed can be dissolved or dispersed in a solvent for extrusion, wherein the solution or dispersion is then discharged through the extruder during extrusion and the solvent is evaporated after the solution or dispersion has been discharged through the extruder, or the extruded material is coagulated in a washing bath by washing out the solvent.

[0045] One example is the production of hollow fibers by solvent spinning, in which a solution / dispersion of the polymer is extruded into hollow fibers and the solvent is then washed out of the polymer in a wash bath, solidifying the polymer into a very thin tube. The wash bath contains a non-solvent for the polymer, but which is readily miscible with the solvent of the polymer solution or dispersion.

[0046] In a second variant, such a method according to the invention comprises the steps of a) producing a film from liner material, in particular by flat extrusion; b) winding the film onto a tubular structure, in particular onto a non-stick coated mandrel, to form a wound liner; c) solidifying the wound film by post-treatment, in particular by tempering, sintering and / or chemical treatment, to form a solidified liner material layer, wherein polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK), is used as the material for the liner. Preferably, no poly- or perfluorinated alkyl substances are incorporated into the liner within the scope of the method.

[0047] In a third variant, such a method according to the invention comprises or consists of the following steps: a) producing at least one fiber layer of the liner by electrospinning, wherein the electrospun fibers are deposited on a tubular structure, in particular a non-stick coated mandrel; b) consolidating the fiber layer by post-treatment, in particular by tempering, sintering, and / or chemical treatment, wherein polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK), is used as the material for the liner. Preferably, no poly- or perfluorinated alkyl substances are incorporated into the liner within the scope of the method.

[0048] In a fourth variant, such a method according to the invention comprises or consists of the following steps: a) producing at least one fiber layer of the liner by electrospinning, wherein the electrospun fibers are deposited on a substantially flat surface; b) winding the at least one fiber layer onto a tubular structure, in particular onto a non-stick coated mandrel; c) consolidating the liner by post-treatment, in particular by tempering, sintering and / or chemical treatment, wherein polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK), is used as the material for the liner. Preferably, no poly- or perfluorinated alkyl substances are incorporated into the liner within the scope of the method.

[0049] The above-described processes according to the second to fourth variants can be advantageously further developed by applying additional liner material layers to the outer side of the liner material layers formed in the process. In preferred variants of the present invention, the electrospun fibers deposited randomly on the mandrel or produced as a continuous nonwoven fabric can be aligned by post-treating the finished tubular liner. In particular, this can be achieved by post-stretching or drawing the liner workpiece. Post-stretching or drawing here means applying a force to the tubular liner structure under irreversible deformation (stretching). This induces fiber alignment, which allows adjustment of the elongation and strength.

[0050] To optimize the liner stretch in the longitudinal direction, in preferred variants of the present invention, filaments parallel to the mandrel / liner axis, e.g. made of aramid, high-performance polyethylene (Dyneema; trademark of Avient) and / or other polymer fibers or wires made of e.g. NiTi and / or stainless steel and / or other metallic workpieces, can be inserted and "tightly" spun in between the individual nonwoven layers of the liner during the espinning process.

[0051] In order to optimize the processing of the polyaryletherketone in the electrospinning process, in preferred variants of the present invention, further polymers can be added to the polyaryletherketone solution.

[0052] In preferred variants of the present invention, aprotic solvents such as dimethylformamide (DMF), dimethylacetamide (DMAc), dimethyl sulfoxide (DMSO), or N-methyl-2-pyrrolidone (NMP) in polar or nonpolar form, and optionally protic polar or nonpolar solvents, can be used as solvents in the electrospinning process. Other related solvents from the group of green solvents, such as dihydrolevoglucosenone, can also be used in the production process.

[0053] In the context of the present invention, solvents selected from the group consisting of aprotic solvents, protic polar solvents, green solvents and mixtures thereof, preferably selected from the group consisting of dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, dihydrolevoglucosenone and mixtures thereof, are preferably used in electrospinning.

[0054] An optimization of the liner properties downstream of the manufacturing process can be achieved by an initial or additional post-treatment of the manufactured tubular structures, e.g. by tempering, sintering or chemically (e.g. cross-linking) as well as by physical cross-linking; these post-treatment steps are commonly known in the art.

[0055] The precise conditions for producing the liners according to the invention can be specifically adapted by the person skilled in the art in order to control the degree of crystallinity of polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK), which in turn allows the mechanical properties to be specifically influenced (at least within a certain framework).

[0056] Other known excipients can be added to the liners according to the invention. In some variants, for example, it is preferred to add UV absorbers or UV stabilizers to the liners. Commonly known substances can be used; their selection is limited only by their potential toxicity or health hazards. Therefore, the person skilled in the art will ensure that these do not lead to contamination of substances that come into contact with the liners.

[0057] Last but not least, the present invention relates to the use of the liners according to the invention for medical catheters.

[0058] A further subject matter of the present invention relates to a catheter equipped with or comprising a liner as described above. The corresponding liner is formed on the inside of the catheter and thus encloses an inner lumen of the catheter. In addition to the liner, the catheter typically comprises at least one further layer formed on the outside of the liner, which can also be made of fibers.

[0059] Finally, the present invention also relates to the use of polyaryletherketone, preferably polyetheretherketone, in particular sulfonated polyetheretherketone for medical catheters or liners for medical catheters and / or for producing medical catheters or liners for medical catheters, in particular in a process according to the present invention, in particular liners for medical catheters according to the present invention.

[0060] The sliding properties of sPEEK achieve a coefficient of friction (COF, at 23°C) of approximately 0.025 when using a 3% NaCl solution as a lubricant. When using distilled water as a lubricant, the COF is approximately 0.04. These values ​​are in a comparable range to those for PTFE (COF = 0.05 - 0.10). The coefficient of friction can be determined using the measurement procedure described in ISO 8295.

[0061] Another advantage is that sulfonated polyetheretherketone can be classified as biocompatible for short-term use (as is typically the case with medical catheters). In addition to good cytocompatibility, sPEEK also exhibits antibacterial properties.

[0062] The use of polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), especially sulfonated polyetheretherketone (sPEEK), for the production of catheter liners solves the problem of providing a replacement material for PTFE that has comparably good sliding properties, especially when moistened. By manufacturing catheter liners from polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), especially sulfonated polyetheretherketone (sPEEK), corresponding therapeutic products can continue to be delivered minimally invasively without the use of PTFE.

[0063] The technical problem underlying the present invention is accordingly solved in particular by replacing PTFE or other PFAS as a material in liner production by polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK).

[0064] An advantage of the present invention is that a method, or rather a material, has been found that enables the replacement of PFAS-contaminated materials or PTFE in liner production and improves the liner's sliding properties. Furthermore, a beneficial effect of the present invention is that the use of sPEEK also creates antibacterial properties in the area of ​​the catheter liner.

[0065] A particular advantage of the present invention is that by using polyaryletherketone (PAEK), preferably polyetheretherketone (PEEK), in particular sulfonated polyetheretherketone (sPEEK), as a material for the production of catheter liners, the use of PTFE or other PFAS can be dispensed with, so that the production of catheters for minimally invasive therapy is still guaranteed even after a ban on PFAS or PTFE.

[0066] The objects of the present invention, in particular the liners and / or catheters according to the invention, can therefore generally be used in catheter-based minimally invasive therapies.

[0067] The various embodiments of the present invention, for example - but not exclusively - those of the various dependent claims or individual embodiments described in the figures, can be combined with one another in any desired manner, even if these combinations are not explicitly mentioned, provided that such combinations do not contradict one another.

[0068] Figures:

[0069] The figures are not to be interpreted in a limiting sense and are not to scale. Furthermore, the figures do not contain all features found in actual embodiments, but are reduced to those essential to the present invention and its understanding.

[0070] Figure 1 shows schematic representations of fiber deposition patterns for liners.Shown from top to bottom as i) to vi) are: i) a placement (=orientation) of the fibers 12 at an angle of +45° (which means tilted to the right in this figure) in relation to the longitudinal axis L of the liner 10, ii) a placement (=orientation) of the fibers 12 at an angle of -45° (which means tilted to the left in this figure) in relation to the longitudinal axis L of the liner 10, iii) a placement (=orientation) of the fibers 12 at an angle of +90° in relation to the longitudinal axis L of the liner 10, the fibers are therefore perpendicular to the longitudinal axis L, iv) a combination of the three variants shown above, i.e. all three placements (=orientations) with the angles +45°, -45° and +90°, each in relation to the longitudinal axis L of the liner 10, v) a combination of the placement (=orientation) of the fibers 12 at an angle of +45° with the placement (=orientation) of the Fibers 12 at an angle of -45°, each with respect to the longitudinal axis L of the respective liner 10, vi) a randomized deposition (=orientation) of the fibers 12.

[0071] In the figure, the longitudinal axis L lies centrally in the respective liners along the schematically illustrated liners 10 from left to right; for the sake of clarity, the longitudinal axis L is illustrated only for the uppermost liner i) as an arrow pointing to the right; it applies analogously to ii) to vi).

[0072] Figure 2 shows an SEM image of electrospun sPEEK fibers according to the present invention.

[0073] List of reference symbols:

[0074] L Longitudinal axis of the liner

[0075] 10 liners

[0076] 12 fibers

Claims

Claims 1. Liner for medical catheters, characterized in that the liner comprises or consists of polyaryletherketone.

2. Liner according to claim 1, characterized in that the polyaryletherketone is a polyetheretherketone, in particular sulfonated polyetheretherketone.

3. Liner according to claim 1 or 2, characterized in that the sulfonated polyetheretherketone has a degree of sulfonation in the range from 40 to 100%, preferably more than 50%, more preferably more than 60%, even more preferably more than 70%, even more preferably more than 80%, and even more preferably more than 90% and / or the polyaryletherketone, in particular the polyetheretherketone or the sulfonated polyetheretherketone, has a molecular weight Mw in the range from 5,000 to 100,000 g / mol, preferably in the range from 10,000 to 80,000 g / mol, more preferably from 15,000 to 60,000 g / mol, and even more preferably 20,000 to 40,000 g / mol.

4. Liner according to one of claims 1 to 3, wherein the liner is formed from fibers produced by electrospinning, and in particular is completely spun.

5. Liner according to one of the preceding claims, in particular according to claim 4, characterized in that the liner comprises at least one electrospun fiber layer, the fibers of which have a uniform orientation, preferably an orientation in an angular range between 0° and 90°, particularly preferably angles of ±45° or 90°, in each case with respect to the mandrel axis, the liner comprises several electrospun fiber layers, the fibers of which are aligned the same or differently, either i) - at an angle of +45° with respect to the longitudinal axis of the liner, or ii) - at an angle of -45° with respect to the longitudinal axis of the liner, or iii) - at an angle of +90° with respect to the longitudinal axis of the liner, or iv) - a combination of variants i), ii), iii), or v) - a combination of variants i) and ii), or vi) - randomized; and / or the liner has a wall thickness of 1 pm to 100 pm, in particular from 2 pm to 50 pm, in particular from 3 pm to 40 pm, in particular from 4 pm to 30 pm, in particular from 5 pm to 25 pm, and / or the liner has an inner diameter of 50 pm to 5000 pm, in particular from 100 pm to 4000 pm, in particular from 200 pm to 3000 pm, in particular from 300 pm to 2250 pm.

6. Liner according to one of the preceding claims, characterized in that in addition to the polyaryletherketone, preferably polyetheretherketone, in particular sulfonated polyetheretherketone, at least one further polymer selected from the group consisting of fluorinated polymers, polyolefins, polyurethanes, polyamides, polyesters, polysulfones, biological polymers, protein-based polymers or mixtures thereof is present, preferably selected from the group consisting of polyolefins, polyurethanes, polyamides, polyesters, polysulfones and mixtures thereof; in particular selected from the group consisting of polypropylenes, polyethylenes, thermoplastic polyurethanes, hydrophilic polyurethanes, polyamide 6.6, polyamide 6.12, polyether block amides, polylactic acids, poly(lactide-co-glycolide), polyethylene terephthalate, polysulfone and mixtures thereof.

7. A method for producing a liner of a medical catheter according to any one of claims 1 to 6, wherein the method comprises producing an inner liner material layer by extrusion of a tube from the Liner material, and optionally the application of further liner material layers to the outside of the inner liner material layer, characterized in that polyaryletherketone, preferably polyetheretherketone, in particular sulfonated polyetheretherketone, is used as the material for the liner.

8. A method for producing a liner of a medical catheter according to any one of claims 1 to 6, wherein the method comprises the steps of: a) producing a film of liner material, preferably by Flat extrusion; b) winding the film onto a tubular structure, in particular onto a non-stick coated mandrel, to form a wound liner; c) solidifying the wound liner by post-treatment, in particular by tempering, sintering and / or chemical treatment, characterized in that polyaryletherketone, preferably polyetheretherketone, in particular sulfonated polyetheretherketone, is used as the material for the liner.

9. A method for producing a liner of a medical catheter according to any one of claims 1 to 6, wherein the method comprises the steps of: a) producing at least one fiber layer of the liner by Electrospinning, wherein the electrospun fibers are deposited on a tubular structure, in particular a non-stick coated mandrel; b) strengthening the fiber layer by post-treatment, in particular by tempering, sintering and / or chemical treatment, characterized in that polyaryletherketone, preferably polyetheretherketone, in particular sulfonated polyetheretherketone, is used as the material for the liner, 10. A method for producing a liner of a medical catheter according to any one of claims 1 to 6, the method comprising the steps of: a) producing at least one fiber layer of the liner by electrospinning, wherein the electrospun fibers are deposited on a substantially flat surface; b) winding the at least one fiber layer onto a tubular structure, in particular onto a non-stick coated mandrel, to form a wound liner; c) solidifying the wound liner by post-treatment, in particular by tempering, sintering and / or chemical treatment, characterized in that polyaryletherketone, preferably polyetheretherketone, in particular sulfonated polyetheretherketone, is used as the material for the liner.

11. The method according to claim 9 or 10, characterized in that in the electrospinning at least one solvent selected from the group consisting of aprotic solvents, protic polar solvents, green solvents and mixtures thereof is used, preferably selected from the group consisting of dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, dihydrolevoglucosenone and mixtures thereof.

12. A medical catheter comprising a liner according to any one of claims 1 to 6.

13. Use of polyaryletherketone, preferably polyetheretherketone, in particular sulfonated polyetheretherketone for medical catheters or liners for medical catheters and / or for the production of medical catheters or liners for medical catheters, in particular in a process according to one of claims 7 to 11, in particular liners for medical catheters according to one of claims 1 to 6

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