Improvements in the extrusion of polymeric materials

Abstract

An extrusion product, such as a film, pipe, or cable / wire sheath, includes a first layer and a second layer. The first layer includes a polymeric material (A) having repeating units of the formula: -0-Ph-0-Ph-CO-Ph I and repeating units of the formula: -0-Ph-Ph-0-Ph-CO-Ph II, where Ph represents a phenylene moiety. The second layer may be a polyaryletherketone (PAEK), such as polyetheretherketone (PEEK). The first layer is intended to reduce the formation of deposits on the die of an extrusion device during extrusion of the product. A method for producing a product including the first layer and the second layer, as well as the use of the polymeric material (A) to reduce the formation of deposits on the die of an extrusion device during extrusion of a second polymeric material, are also described.

Description

[Technical Field]

[0001] The present invention relates to extruded products, methods for making extruded products, and uses of polymeric materials. In particular, the present invention relates to extruded products that reduce the formation of deposits on the die of an extrusion apparatus during extrusion. [Background technology]

[0002] Elongated products (herein referred to as extruded products), e.g., films or pipes, having a specific, uniform cross-sectional profile can be formed using an extrusion process. A typical extrusion process involves forcing one or more flowable polymeric materials through an extrusion die. Such dies include an outlet for the polymeric material shaped to impart a desired cross-sectional profile to the product. Some polymeric materials have a tendency to adhere to the edges of the die outlet, gradually forming significant deposits on the die outlet. These deposits, sometimes referred to as "die drool" (also known as "die buildup," "die drip," "die peel," "die bleed," or "plateout"), can adversely affect product and process quality, for example, by imprinting patterns on the surface of the extruded product or by flaking off at random intervals and contaminating the product.

[0003] Manually removing such die draw rolls from the die during the process is often difficult or impossible without affecting the extruded product being formed. Thus, when such die draw rolls form and begin to adversely affect product quality, the process may have to be stopped and the extrusion equipment, particularly the die, cleaned. This can involve disassembly of the extrusion equipment and therefore a significant amount of downtime for the manufacturing process.

[0004] For these reasons, polymeric materials with a relatively high tendency to form die drools may only be used to produce extruded products in relatively short production runs, which is inefficient and therefore more expensive than processes using polymeric materials with a lower tendency to form die drools.

[0005] This problem can be exacerbated when the polymeric material contains a filler material, e.g., a particulate filler such as talc. Such filler materials often increase the formation of die draw. Such filler materials can provide benefits to extruded products formed from the polymeric material, such as improved strength, stiffness, impact resistance, heat resistance, electrical insulation, and chemical stability. The benefits provided by such filler materials may outweigh the problems caused by increased die draw. However, it would be desirable to reduce die draw in the production of extruded products using such filled polymeric materials so that process efficiency and extruded product quality could be improved.

[0006] This problem can also be exacerbated when extrusion equipment is operating at increased line speeds. As line speeds increase, pressure in the die increases from faster extrusion screw speeds, which can lead to greater swelling of the melt at the exit from the die and therefore increased die droop. It would be desirable to reduce die droop in the production of extruded products to allow for the use of faster line speeds. Summary of the Invention [Problem to be solved by the invention]

[0007] Polyaryletherketones (PAEKs), such as polyetheretherketone (PEEK) and polyetherketone (PEK), are well-known high-performance thermoplastic polymers that generally possess excellent mechanical and chemical resistance. Filler materials, such as glass fiber, carbon fiber, and particulates such as talc, can further improve certain properties of these polymers. However, the present inventors have discovered that the filler materials present in such polymers increase the tendency for die-roll formation, thus adversely affecting extruded products formed from such filled PAEK polymers and reducing the efficiency of their manufacturing processes. [Means for solving the problem]

[0008] One object of the present invention is, inter alia, to provide an extrusion product, method, or use that addresses at least one shortcoming of the prior art, whether identified herein or elsewhere, or to provide an alternative to existing extrusion products, methods, and uses. For example, an object of the present invention may be to provide an extrusion product that is less prone to die-draw during extrusion than a comparable extrusion product.

[0009] According to aspects of the present invention there are provided extruded products, methods and uses as set out in the accompanying claims. Other features of the invention will become apparent from the dependent claims and the following description.

[0010] According to a first aspect of the present invention, there is provided an extruded product comprising a first layer and a second layer, the first layer comprising a compound represented by the formula: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of formula: -O-Ph-Ph-O-Ph-CO-Ph- II and a polymer material (A) having a repeating unit of In the formula, Ph represents a phenylene moiety.

[0011] By extruded product is meant an elongated product having a cross-section formed by the extrusion process, preferably by extrusion through a die that imparts a specific, preferably uniform, cross-sectional profile to the product. Alternatively, the extruded product of this first aspect may be referred to as an elongated product, preferably having a uniform cross-section. Examples of such extruded / elongated products include films, cable sheathing, including but not limited to wire and cable insulation, pipes, and filaments.

[0012] The polymeric material (A) is a polyaryletherketone (PAEK) polymer. More specifically, the polymeric material (A) is a copolymer of poly(ether ether ketone) (PEEK) and poly(ether diphenyl ether ketone) (PEDEK), where the repeating unit of Formula I (which may be referred to as EEK) provides the PEEK polymer component and the repeating unit of Formula II (which may be referred to as EDEK) provides the PEDEK. Thus, the polymeric material of Formula (A) can be referred to as a PEEK / PEDEK copolymer.

[0013] The inventors have discovered that polymeric material (A) has a reduced tendency to form die drapes when extruded through a die at elevated temperatures. Thus, extruded products can be formed from polymeric material (A) without the adverse effects on product quality and process efficiency caused by die drapes, as described above, that can occur when extruding similar polymers, such as PEEK homopolymer. In the extruded product of this first embodiment, polymeric material (A) provides an outer layer, a first layer, with reduced die drapes, that can effectively shield the inner second layer from the die upon exiting the extrusion apparatus used to produce the extruded product, so that the second layer does not produce die drapes that can adversely affect product quality or process efficiency. This is, of course, particularly advantageous when the material of the second layer, preferably a second polymeric material, has a much higher tendency to produce die drapes than polymeric material (A). As a result, the extruded product of this first embodiment preferably has fewer defects caused by die drapes than a comparable extruded product that does not include an outer layer of polymeric material (A). Also, the extrusion process used to form the extruded product may have a significantly longer run time than a comparable process that does not include the use of an outer layer of polymeric material (A) before the process must be stopped to clean the extrusion equipment, which preferably provides a more efficient overall process for the production of such extruded products, such as films, cable jackets, filaments, and pipes.

[0014] As described in more detail below, the present invention may also allow higher levels of filler to be included in the polymeric material of the inner layer of the extruded product than would be possible without the filler adversely affecting the extrusion process. Such higher levels of filler may be desirable to improve the properties of the extruded product, such as electrical corona discharge resistance.

[0015] Furthermore, the present invention may also enable higher line speeds to be used in the manufacture of extruded products. Increasing line speeds can cause die draw, which makes it impractical to increase line speeds beyond a certain limit. However, because the present invention reduces die draw, higher line speeds can be achieved, increasing manufacturing output and efficiency.

[0016] The use of polymeric material (A) in the first layer as an outer layer in the extruded product may also provide another advantage in reducing other surface defects or distortion-related phenomena that can occur during the extrusion of some polymeric materials, such as cracking of the surface of the extruded material. Polymeric material (A) is preferably much less prone to such defects.

[0017] The first layer is the outer layer of the extruded product. The term "outer layer" is used herein to refer to the layer or layers of the extruded product that contact the die used to form the product as the product exits the die. In some embodiments, the extruded product is formed by a process involving only one surface of the product contacting the die at the exit. In such embodiments, the first layer is preferably the only outer layer of the extruded product, typically the outermost layer or surface of the extruded product. The second layer is an inner layer of the extruded product. In some embodiments, the extruded product is formed by a process in which two surfaces of the product contact the die at the exit. In such embodiments, the extruded product includes a third layer, the second layer being disposed between the first and third layers. In this embodiment, the extruded product preferably has only two outer layers, typically the first layer being the outermost layer or surface of the extruded product, and the third layer being the innermost layer or surface of the extruded product.

[0018] The terms "outer layer" or "first outer layer" may be used interchangeably with the term "first layer." The term "inner layer" may be used interchangeably with the term "second layer." The term "second outer layer" may be used interchangeably with the term "third layer."

[0019] Generally, the polymer has a terminal unit of the polymer that may be the same as the repeat unit, but has a terminal OH group or a terminal F group. However, the method for forming the polymer may also include a separate end-capping step upon completion of the polymerization, in which case a separate monomer or reagent may be added as an end-capping agent, so that the terminal unit may be different from the repeat unit of the polymer. Such end-capping is well known in the field of nucleophilic polycondensation reactions.

[0020] The polymer preferably contains repeating units I and II in a molar ratio I:II of 95:5 to 50:50, or 90:10 to 60:40. Polymeric material (A) is preferably semi-crystalline and generally has a crystalline melting point lower than that of the homopolymer of repeating unit I or the homopolymer of repeating unit II. However, the glass transition temperature of polymeric material (A) is generally the same as or slightly higher than that of the homopolymer of repeating unit I. More specifically, polymeric material (A) preferably has a glass transition temperature of from greater than 143°C to 160°C and a crystalline melting temperature of from 300°C to 330°C. In particular, a polymer containing repeating units I and II in a relative ratio of 80:20 has a glass transition temperature of about 149°C and a crystalline melting temperature of about 309°C.

[0021] The phenylene moieties (Ph) of each repeat unit can independently have 1,4-para or 1,3-meta bonds to the atoms to which they are attached. When the phenylene moieties contain 1,3-linkages, the moieties will reside in the amorphous phase of the polymer. The crystalline phase will contain phenylene moieties with 1,4-linkages. For many applications, it is desirable for the polymeric material to be highly crystalline; therefore, the polymeric material preferably contains a high level of phenylene moieties with 1,4-linkages.

[0022] Suitably, at least 95%, or at least 99%, of the number of phenylene moieties (Ph) in the repeat unit of formula I have a 1,4-linkage to the moiety to which they are attached. It is particularly preferred that each phenylene moiety in the repeat unit of formula I has a 1,4-linkage to the moiety to which it is attached.

[0023] Suitably, at least 95%, or at least 99%, of the number of phenylene moieties (Ph) in the repeat unit of formula II have a 1,4-linkage to the moiety to which they are attached. It is particularly preferred that each phenylene moiety in the repeat unit of formula II has a 1,4-linkage to the moiety to which it is attached.

[0024] Preferably, the phenylene moiety in the repeat unit of formula I is unsubstituted. Preferably, the phenylene moiety in the repeat unit of formula II is unsubstituted. The repeat unit of formula I preferably has the structure Ia:

[0025] [ka]

[0026] It has. The repeat unit of formula II preferably has the structure IIa:

[0027] [ka]

[0028] It has. The polymeric material (A) may comprise at least 68 mol%, preferably at least 71 mol%, of repeating units of formula I. Particularly advantageous polymeric materials (A) may comprise at least 72 mol%, or in particular at least 74 mol%, of repeating units of formula I. The polymeric material (A) may comprise less than 90 mol%, suitably not more than 82 mol%, of repeating units of formula I. The polymeric material (A) may comprise 68 to 82 mol%, preferably 70 to 80 mol%, more preferably 72 to 77 mol% of units of formula I.

[0029] The polymeric material (A) may contain at least 10 mol%, preferably at least 18 mol%, of repeating units of formula II. The polymeric material (A) may contain less than 32 mol%, preferably less than 29 mol%, of repeating units of formula II. Particularly advantageous polymeric materials (A) may contain 28 mol% or less, or 26 mol% or less, of repeating units of formula II. The polymeric material (A) may contain 18 to 32 mol%, preferably 20 to 30 mol%, more preferably 23 to 28 mol% of units of formula II.

[0030] The sum of the mole percentages of units of formula I and II in the polymeric material (A) is suitably at least 95 mole%, preferably at least 98 mole%, more preferably at least 99 mole%, especially about 100 mole%.

[0031] The ratio, defined as the mole % of units of formula I divided by the mole % of units of formula II, may range from 1 to 10, may be in the range of 1.8 to 5.6, is suitably in the range of 2.3 to 4, and is preferably in the range of 2.6 to 3.3.

[0032] The polymeric material (A) preferably has a lower melting temperature (Tm) than the material of the inner layer, as measured by differential scanning calorimetry (DSC). The polymeric material (A) may have a melting temperature that is at least 10°C lower, such as at least 20°C lower, for example at least 30°C lower, than the material of the inner layer.

[0033] Further suitable polymeric materials of formula (A) (PEEK / PEDEK copolymers) are as described in U.S. Pat. No. 4,717,761, WO 2014 / 207458 A1 and WO 2015 / 124903 A1, the contents of which are incorporated herein by reference.

[0034] WO 2014 / 207458(A1) discloses a method for producing a polymer having repeating units of formula I and II in a molar ratio of 55:45 to 95:5, at 340°C and 1000s -1 A melt viscosity (MV) measured at a shear rate of at least 0.25 and 1.2 kNsm -2 discloses a PEEK / PEDEK copolymer having less than

[0035] WO 2015 / 124903(A1) discloses a method for producing a polymer having repeating units of formula I and II in a molar ratio of 55:45 to 95:5, at 340°C and 1000s -1 discloses PEEK / PEDEK copolymers having a MV of at least 0.25 and less than 1.2 measured at a shear rate of 100 .mu.m.

[0036] In some embodiments, the polymeric material (A) may be as described in WO 2022013520(A1), the contents of which are incorporated herein by reference. In such embodiments, the polymeric material (A) may be a polymer having Formula I: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of Formula IIa:

[0037] [ka]

[0038] and a terminal unit, the molar ratio of the repeating unit of formula I to the repeating unit of formula IIa is 50:50 to 95:5; The repeating units of formula I are 50 to 90 mol % of the repeating units of formula Ia:

[0039] [ka]

[0040] and 10 to 50 mol % of repeating units of formula Ib, repeating units of formula Ic, or a mixture thereof, The repeat unit of formula Ib is

[0041] [ka]

[0042] and The repeat unit of formula Ic is

[0043] [ka]

[0044] is. Preferably, the molar ratio of repeat units of formula I to repeat units of formula II is from 50:50 to 95:5, preferably from 60:40 to 90:10, more preferably from 70:30 to 90:10.

[0045] The repeating units of formula I consist essentially of, or preferably consist of, 50-90 mol% of repeating units of formula Ia in combination with 10-50 mol% of repeating units of formula Ib and / or formula Ic. Preferably, the repeating units of formula I consist essentially of, or preferably consist of, 65-90 mol% of repeating units of formula Ia in combination with 10-35 mol% of repeating units of formula Ib, formula Ic, or a mixture thereof. More preferably, the repeating units of formula I consist essentially of, or preferably consist of, 80-90 mol% of repeating units of formula Ia in combination with 10-20 mol% of repeating units of formula Ib, formula Ic, or a mixture thereof.

[0046] The repeating unit Ia is R PEEK The repeating unit Ib is called R mPEEK The repeating unit Ic is called R oPEEK It is called. Thus, in other words, the repeat units of formula I are in the molar ratio: R PEEK :(R mPEEK +R oPEEK ) is expressed as 90:10 to 50:50, preferably 90:10 to 65:35, more preferably 90:10 to 70:30, and more preferably 90:10 to 80:20.

[0047] In a particularly preferred embodiment, the polymeric material (A) is a copolymer as described above, in which the molar ratio of repeat units of formula I to repeat units of formula II is from 90:10 to 70:30, and the repeat units of formula I consist essentially of, or preferably consist of, 80 to 90 mole % of repeat units of formula Ia in combination with 10 to 20 mole % of repeat units of formula IIb, formula Ic, or a mixture thereof.

[0048] Formula I: -O-Ph-O-Ph-CO-Ph- does not provide information regarding whether the ether linkage of the -O-Ph-O- moiety is arranged in the para-, meta-, or ortho-configuration, but it will be understood that this, as well as all other configurations within the repeat unit, is specific to Formulas Ia, Ib, and Ic.

[0049] In one embodiment, the copolymer according to the first aspect of the present invention may be a copolymer that does not include a repeat unit of formula Ib. In another embodiment, the copolymer according to the first aspect of the present invention may be a copolymer that does not include a repeat unit of formula Ic.

[0050] Preferably, polymeric material (A) provides up to 100% by weight of the outer layer, preferably up to 95% by weight or up to 90% by weight of the outer layer. Polymeric material (A) may provide at least 70% by weight, at least 80% by weight or at least 85% by weight of the outer layer. Preferably, polymeric material (A) provides 70-100% by weight of the outer layer, 80-95% by weight or 85-95% by weight of the outer layer.

[0051] Suitably, the first layer consists essentially of or consists of the polymeric material (A) as defined above. The first and second layers of the extruded product may have a combined thickness of at most 5 mm, preferably at most 3 mm or at most 2 mm. Preferably, the first and second layers of the extruded product may have a combined thickness of at least 10 μm, preferably at least 50 μm or at least 100 μm.

[0052] The thickness of the first layer is preferably less than the thickness of the second layer. The second layer may provide 50 to 95% of the combined thickness of the first and second layers. The first layer preferably provides 5 to 50% of the combined thickness of the first and second layers.

[0053] Preferably, the extruded product of this first aspect includes a third layer. The third layer is a second outer layer. In such an embodiment, the first layer referred to above may be considered to be the first outer layer. Preferably, the second layer is disposed between the first layer and the third layer. Thus, the extruded product preferably has an ABA sandwich structure, with the A layer being the first and second outer layers and the B layer being the inner layer.

[0054] Preferably, the third layer comprises the polymer material (A) described above, i.e., a polymer of the formula: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of formula: -O-Ph-Ph-O-Ph-CO-Ph- II and a polymer material (A) having a repeating unit of In the formula, Ph represents a phenylene moiety.

[0055] Preferably, the third layer consists essentially of or consists of the polymeric material (A) as defined above. Preferably, the third layer is the same as the first layer. The first layer and / or the third layer may comprise a release agent. Preferably, the first layer comprises a release agent. Suitable release agents are known in the art and may be selected from metal stearates, erucamide, oleamide, or fluoropolymers.

[0056] The second layer of the extruded product of this first embodiment can comprise a polymeric material that can be referred to as the second polymeric material. Preferably, the second layer comprises a polyaryletherketone (PAEK). Preferably, the second layer comprises a PEEK polymer, i.e., a polymer having the formula: -O-Ph-O-Ph-CO-Ph- I a polymer material (B) having a repeating unit of In the formula, Ph represents a phenylene moiety.

[0057] Suitably, at least 95%, or at least 99%, of the number of phenylene moieties (Ph) in polymeric material (B) have a 1,4-linkage to the moiety to which they are attached. It is particularly preferred that each phenylene moiety in polymeric material (B) has a 1,4-linkage to the moiety to which it is attached.

[0058] Preferably, the phenylene moiety in the repeat unit of formula I is unsubstituted. The polymeric material (B) comprises at least 68 mol %, preferably at least 71 mol %, of formula Ia:

[0059] [ka]

[0060] It may contain repeating units of the formula: Suitably, the polymeric material (B) comprises at least 80 mol%, preferably at least 90 mol%, more preferably at least 95 mol%, especially at least 99 mol% of repeat units of formula I, especially repeat units of formula Ia. Thus, the polymeric material (B) is preferably a homopolymer, which is preferably polyetheretherketone (PEEK).

[0061] Suitable PEEK polymer materials are available from Victrex Manufacturing Ltd., such as VICTREX PEEK 150G, 151G, 381G, 450G, and 650G (all of which are examples of PEEK polymer materials). VICTREX AE™ 250 is an example of a PEEK-PEDEK polymer material.

[0062] PAEK, particularly PEEK, can be produced by nucleophilic polycondensation of bisphenols with organic dihalide compounds in a suitable solvent in the presence of alkali metal carbonates and / or bicarbonates or alkaline earth metal carbonates and / or bicarbonates. Such processes are described, for example, in EP 0001879 (A), EP 0182648 (A), EP 0244167 (A), and EP 3049457 (A). PAEK can be produced according to WO 2018055384, which is incorporated herein by reference.

[0063] Such polyaryletherketones may have relatively high melting temperatures and may be susceptible to oxidation and other decomposition processes during the extrusion process which can cause the die draw described above.

[0064] Preferably, the second layer of the extruded product of this embodiment comprises a filler material. The filler material may comprise at least 5% by weight of the material of the second layer, preferably at least 10% or at least 15% by weight of the second layer. The filler material may provide up to 50%, 40%, or 30% by weight of the second layer. Preferably, the filler material provides 5-50% by weight of the second layer, 10-40% by weight, or 15-35% by weight of the second layer. The present invention may allow for higher levels of filler to be included in the polymeric material of the inner layer of the extruded product than would be possible without adversely affecting the extrusion process, for example, greater than 20%, preferably 25%, 30%, or 40% by weight. Such higher levels of filler may be desirable to improve the properties of the extruded product, such as electrical corona discharge resistance.

[0065] In such embodiments, the second polymeric material, such as polymeric material (B), preferably provides up to 95% by weight of the material of the second layer, preferably up to 90% by weight or up to 85% by weight of the second layer. The second polymeric material may provide at least 50%, at least 60%, or at least 70% by weight of the second layer. Preferably, the second polymeric material provides 50-95% by weight of the second layer, 60-90% by weight, or 65-85% by weight of the second layer.

[0066] The filler material may be a fibrous filler material or a particulate filler material. The fibrous filler material preferably has a longest dimension of 300 μm or less. Suitable fibrous filler materials may be selected from inorganic fibrous materials, organic fibrous materials such as aramid fibers, and carbon fibers. Preferably, the melting temperature of the fibrous filler should be at least 450°C. Suitable fibrous filler materials may be selected from glass fibers, carbon fibers, asbestos fibers, silica fibers, alumina fibers, zirconia fibers, boron nitride fibers, silicon nitride fibers, boron fibers, fluorocarbon resin fibers, and potassium titanate fibers, or mixtures thereof. Preferred fibrous fillers are glass fibers and carbon fibers.

[0067] In some embodiments, the filler material is a particulate filler material. Suitable particulate (or non-fibrous) filler materials may be selected from mica, silica, talc, alumina, kaolin, calcium sulfate, calcium carbonate, titanium oxide, ferrite, clay, glass powder, zinc oxide, nickel carbonate, iron oxide, quartz powder, boron nitride powder, magnesium carbonate, fluorocarbon resin, graphite, graphene, graphene oxide, carbon powder, ceramic powder, metal powder, flame retardant powder, nanotubes, and barium sulfate, or mixtures thereof. Non-fibrous fillers can be introduced in the form of powder or flake particles. Preferably, the particulate filler material is talc.

[0068] The particle size of the filler material is preferably in the range of 1 to 10 μm, preferably 2 to 5 μm, hi some embodiments, the filler material is in the form of platelets. Preferably, the filler material has a D50 of 0.001 to 50 μm, more preferably 0.005 to 15 μm. Preferred filler materials have a D50 of less than 10 μm. Preferably, the filler material has a D50 of 1 to 5 μm, for example 3 to 5 μm. D50 is measured by laser Mastersizer laser diffraction, Mie theory (according to ISO 13320-1).

[0069] Preferably, the filler material provides the second layer material, e.g., the polymer material (B) defined above, with improved properties such as improved strength, ductility, heat resistance, chemical resistance, or electrical resistance. For example, the filler material may provide improved dielectric properties and / or electrical breakdown performance. In embodiments where the filler material is talc and the extruded product is a coating or sheath for wire, the talc filler preferably improves the electrical breakdown properties of the wire coating at relatively high voltages, e.g., 800 V. Such wire may be particularly suitable for use in electric motors, where high voltages can be advantageous for reducing power losses.

[0070] As mentioned above, the inclusion of such a filler material can result in increased die draw and thus impair the quality of the extruded product and the efficiency of the manufacturing process. Therefore, the extruded product of this first aspect can be particularly advantageous when a second layer, such as the polymeric material (B) defined above, includes such a filler material. In such an embodiment, the extruded product preferably provides the beneficial property of having a filler material in the bulk of the product (in an inner layer) while avoiding the associated tendency to form die draw during extrusion by having an outer layer of polymeric material (A) covering the second layer.

[0071] The second layer material including the filler material may be prepared by any suitable method known in the art. Preferably, the second layer material including the filler material is prepared by single screw extrusion compounding or twin screw extrusion compounding, preferably twin screw extrusion compounding.

[0072] Suitably the second layer of the extruded product of this first aspect consists of or consists essentially of the second polymeric material as defined above and any filler material present. The first layer, the second layer, and / or the third layer may include one or more pigments to change the color of the material, which may be useful in identifying the material during the manufacturing process. Optionally, the pigment may be TiO2 or carbon black.

[0073] In some embodiments of the extruded product of this first aspect, the extruded product is in the form of a film. Preferably, the film comprises a first outer layer of polymeric material (A) as the first layer, an inner layer of polymeric material (B) as the second layer, and a second outer layer of polymeric material (A) as the third layer, the second layer being disposed between the first and third layers (ABA configuration). Preferably, the second layer comprises polymeric material (B) and a filler material as defined above. Preferably, the first layer of polymeric material (A), the third layer of polymeric material (A), and the second layer of polymeric material (B) are coaxially disposed to form the film.

[0074] The film may have a total thickness of 3 to 1,000 mm. The second layer preferably provides 40 to 90% of the total film thickness. The first layer and / or the third layer preferably provide 5 to 30% of the total film thickness.

[0075] For example, in end uses where the film is used as a coating layer on wire for insulated conductors, the typical range is in the submicrometer range. Therefore, the film may have a total thickness of 3 to 1,000 μm. The second layer preferably provides 40 to 90% of the total film thickness. The first and / or third layer preferably provides 5 to 30% of the total film thickness.

[0076] In some embodiments of the extruded product of this first aspect, the extruded product is in the form of a pipe. Preferably, the pipe comprises a first outer layer of polymeric material (A) as the first layer, an inner layer of polymeric material (B) as the second layer, and a second outer layer of polymeric material (A) as the third layer, the second layer being disposed between the first and third layers (ABA configuration). Preferably, the second layer comprises polymeric material (B) and a filler material as defined above.

[0077] In such an embodiment, the pipe may have a wall thickness of 0.5 to 10 mm. The second layer preferably provides 40 to 90% of the pipe's wall thickness. The first and / or third layer preferably provide 5 to 30% of the pipe's wall thickness.

[0078] In such embodiments, the inclusion of polymeric material (A) may advantageously improve the physical properties of the pipe by reducing the adverse effects of die drooling, particularly in pipes containing fillers such as talc in the second (inner) layer, which may have an increased tendency to form die drooling. This may allow longer lengths of pipe to be produced than would be possible if more die drooling were produced. Also, reduced die drooling allows for longer and faster run times, providing increased manufacturing efficiency.

[0079] The pipe may have a length of at least 5 m, at least 10 m, at least 50 m, or at least 100 m, preferably has a substantially uniform cross-section along its entire length, and preferably is formed in a single continuous extrusion, hi some embodiments, the pipe may have a length of at least 500 m, at least 1 km, or at least 2.5 km.

[0080] The pipe may have an outer diameter of at least 0.5 cm, at least 2.5 cm, at least 10 cm, or at least 15 cm. The pipe may have an outer diameter of less than 50 cm, less than 40 cm, or less than 30 cm. In some embodiments, the pipe has an outer diameter in the range of 0.5 cm to 50 cm. In some embodiments, the pipe has an outer diameter in the range of 2.5 cm to 30 cm.

[0081] The outer diameter of a pipe can be defined as "d" cm, and the thickness of the pipe wall can be defined as "t" cm. Thus, a diameter to thickness ratio (d / t) can be defined for the pipe. In some embodiments, the diameter to thickness ratio of the pipe is at least 6. The diameter to thickness ratio of the pipe can also be in the range of 6-40 or 15-40.

[0082] In some embodiments of the extrusion product of this first aspect, the extrusion product is in the form of a wire or cable sheath. Preferably, the wire or cable sheath comprises an outer layer of polymeric material (A) as a first layer and an inner layer of polymeric material (B) as a second layer. Preferably, the first layer of polymeric material (A) and the second layer of polymeric material (B) are coaxially arranged to form the wire or cable sheath. The wire or cable sheath may be extruded directly onto the wire or cable to surround the cable or wire. The extrusion product can therefore be considered a cable or wire assembly comprising an inner cable or wire and a sheath, where the sheath surrounds the wire or cable and the sheath comprises a first layer of polymeric material (A) and a second layer of polymeric material (B) as described above. In such embodiments, the second layer preferably comprises a filler material, preferably a particulate filler material, which provides increased electrical insulation to the second layer, and thus to the sheath as a whole. In such embodiments, the AB arrangement of layers may be particularly suitable for the manufacture of wires or cables, where the wire or cable sheath exits the extruder in contact with the wire or cable being coated. The first layer of polymeric material (A) preferably reduces or prevents die drool formation from the upper surface of the second layer of polymeric material (B), which may form on the die as the polymeric material (B) exits the extruder die in the absence of the first layer of polymeric material (A). Die drool formation from the lower surface of the second layer of polymeric material (B) is preferably prevented by the second layer, which is in direct contact with the wire or cable as it exits the extruder.

[0083] In some embodiments of the wire or cable sheath, the wire or cable sheath may include a first outer layer of polymeric material (A) as the first layer, an inner layer of polymeric material (B) as the second layer, and a second outer layer of polymeric material (A) as the third layer, with the second layer disposed between the first and third layers (in an ABA configuration). Preferably, the first layer of polymeric material (A), the third layer of polymeric material (A), and the second layer of polymeric material (B) are coaxially disposed to form the wire or cable sheath. The wire or cable sheath may be extruded directly onto the wire or cable. Thus, the extruded product can be considered a cable or wire assembly including an inner cable or wire and a sheath, with the sheath including the first layer of polymeric material (A), the third layer of polymeric material (A), and the second layer of polymeric material (B) as described above. In such embodiments, the second layer preferably comprises a filler material, preferably a particulate filler material, which provides increased electrical insulation to the second layer, and thus to the sheath as a whole. In such embodiments, the ABA arrangement of layers may be particularly suitable for wire or cable manufacturing, where the wire or cable sheath exits the extruder without contacting the wire or cable and is then contacted with the wire or cable. The two outer layers of polymer material (A) preferably reduce or prevent die-draw formation from both the upper and lower surfaces of the second (inner) layer of polymer material (B), which may form when polymer material (B) exits the extruder in the absence of the two outer layers of polymer material (A).

[0084] Preferably, the second layer comprises talc, preferably talc platelets having a particle size in the range of 1 to 10 μm or 2 to 5 μm. As discussed above, such filler materials can provide improved dielectric and / or electrical breakdown performance, particularly improved electrical breakdown of the wire sheath at relatively high voltages, e.g., 800 V. Additionally, such filler materials can improve resistance to corona discharge in electric machines. Such wires may be particularly suitable for use in electric motors, where high voltages can be advantageous for reducing power losses.

[0085] In such an embodiment, the first and second layers of the wire or cable sheath may have a combined thickness in the range of 50 to 300 μm, preferably in the range of 100 to 200 μm, and the first, second and third layers may have the same combined thickness.

[0086] The wire or cable within the wire or cable sheath may have a circular cross section. In some embodiments, the wire or cable may have a rectangular, square, hexagonal, or stranded cross section. The cross section of the wire or cable may be 1 mm or less. 2 ~100mm 2 , preferably 2 mm 2 ~80mm 2 or 2 mm 2 ~10mm 2 may have an area of

[0087] The thickness of the first layer and / or the third layer is preferably less than the thickness of the second layer of the wire or cable sheath. The second layer may provide 50 to 95% of the combined thickness of the first and second layers, or the first, second and third layers. The first and / or the third layer preferably provides 5 to 50% of the combined thickness of the first and second layers, or the first, second and third layers.

[0088] The wire or cable assembly may include a fourth layer disposed between the cable or wire and the second layer, which may preferably be an adhesive layer that improves adhesion of the sheath to the cable or wire.

[0089] In some embodiments of the extruded product of this first aspect, the extruded product is in the form of a filament. Such filaments may be useful as input materials for additive manufacturing. Preferably, the filament comprises a first layer of polymeric material (A) and a second layer of polymeric material (B), the second layer forming a core of the filament and the first layer surrounding the core. Preferably, the first layer of polymeric material (A) and the second layer of polymeric material (B) are coaxially arranged to form the filament.

[0090] In such embodiments, the filaments may have a thickness of 0.2 to 5 mm, preferably 1.0 mm to 3.0 mm or 1.5 to 2.0 mm. The second layer preferably provides 50 to 95% of the thickness of the filaments. The first layer preferably provides 5 to 50% of the thickness of the filaments.

[0091] Such filaments may advantageously comprise a filler as defined above in the core (i.e., second layer), for example a conductive filler, which, in the absence of an outer (first) layer of polymer material (A) to prevent the core from contacting the surface of the die outlet upon extrusion from the die, could cause die draw during extrusion.

[0092] According to a second aspect of the present invention, there is provided a method of manufacturing a product comprising a first layer and a second layer, the method comprising: a) Formula: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of formula: -O-Ph-Ph-O-Ph-CO-Ph- II providing a source of polymeric material (A) having repeat units of (wherein Ph represents a phenylene moiety), b) providing a source of a second polymeric material; c) delivering the polymeric material (A) and the second polymeric material to an extrusion station comprising a die; d) extruding the polymeric material (A) and the second polymeric material through the die such that the polymeric material (A) contacts the outlet of the die during extrusion and the second polymeric material does not contact the die during extrusion to form an extruded product.

[0093] Preferably, the steps of the method are carried out in the following order: step a) and step b) (preferably simultaneously), followed by step c), followed by step d). Preferably, the introduction and extrusion of polymeric material (A) and the second polymeric material are arranged so that the second polymeric material is covered by polymeric material (A) at the die exit and does not contact the die exit. Preferably, polymeric material (A) forms an outer layer surrounding the second polymeric material, which forms the inner layer of the extruded product at or just before the die exit. Thus, polymeric material (A) prevents the second polymeric material from contacting the die surface at or near the die exit to provide the die droop reduction described herein.

[0094] The polymeric material (A) may have any of the suitable features and advantages described above in relation to the first aspect. The product produced by the method of this second aspect may have any of the suitable features or advantages of the extruded product described above in relation to the first aspect. The polymeric material (A) provided in step a) suitably provides a first layer of the extruded product described in relation to the first aspect. The second polymeric material provided in step b) suitably provides a second layer of the extruded product described in relation to the first aspect.

[0095] The second polymeric material provided in step b) may have any of the suitable features and advantages of the material of the second layer, i.e. the second polymeric material is preferably the polymeric material (B) described in relation to the first embodiment.

[0096] The method of this second aspect preferably involves extruding the second polymeric material through a die without the polymeric material (A) and therefore causing a reduced amount of die draw compared to a comparable process in which the second polymeric material contacts the die, specifically the die exit, during extrusion. This method is therefore particularly advantageous when it is desired to produce an extruded product from a second polymeric material, e.g., a polymeric material (B) as described above, which, despite having advantageous properties, may contain filler materials that cause die draw that adversely affect product quality and reduce the efficiency of the manufacturing process due to the need to periodically stop the process to remove the die draw deposits.

[0097] Additionally, the method of the present invention provides for higher line speeds used in the production of extruded products. Increasing line speeds can cause die draw, which makes it impractical to increase line speeds beyond a certain limit. However, the present invention reduces die draw, making it possible to achieve higher line speeds, increasing manufacturing output and efficiency. Typically, extrusion assemblies can operate at approximately 10 meters / minute. Advantageously, the present invention provides line speeds of approximately 50 meters / minute or greater. Preferably, the line speed may be less than 100 meters / minute, preferably 30 to 80 meters / minute, and preferably 40 to 60 meters / minute.

[0098] Suitably, the second polymeric material comprises a filler as described in relation to the first aspect. As mentioned above, the presence of filler in the polymeric material may increase the formation of die drool.

[0099] The method of this second aspect may be carried out in a suitable extrusion apparatus comprising a first feeding arrangement for feeding a polymeric material (A) in molten form to an extrusion die, and a second feeding arrangement for feeding a second polymeric material in molten form to the extrusion die, wherein the second polymeric material is extruded as an inner layer and the polymeric material (A) is extruded as an outer layer of the product (i.e., the first layer and second layer described herein).

[0100] Preferably, step c) of the method comprises delivering the polymeric material (A) to an extrusion station comprising a die to provide a first outer layer of the product and a second outer layer of the product, the second polymeric material forming an inner layer (i.e., the first, second and third layers described herein) disposed between the first and second outer layers. This preferably comprises an extrusion apparatus comprising a third feeding arrangement for feeding a second stream of the polymeric material (A) in molten form to the extrusion die to provide the second outer layer of the product.

[0101] Preferably, step d) is carried out at a temperature of at least 300°C, at least 320°C, or at least 350°C. Preferably, step d) is carried out at a temperature of at most 430°C, at most 400°C, or at most 380°C.

[0102] Preferably, when polymeric material (B) is PEEK or PEEK and a filler (e.g., 30% talc-filled PEEK), step (d) is suitably carried out at a temperature above the melting temperature of polymeric material (B), preferably at least 350 degrees Celsius.

[0103] Preferably, step (d) is carried out at a temperature above the melting temperature of polymeric material (A), preferably at least 325 degrees Celsius. Preferably, the temperature is the temperature of the die during the process, preferably the temperature at the die exit during the process.

[0104] Preferably, the method is carried out continuously for at least 1 hour, at least 5 hours, at least 10 hours, at least 15 hours, or at least 24 hours. The reduction in die draw caused by the use of polymeric material (A) preferably allows the run time of the method for producing a product by extrusion to be increased compared to a similar method in which polymeric material (A) is not used as the layer contacting the die outlet.

[0105] According to a third aspect of the present invention, there is provided a use of a polymeric material (A) for reducing the formation of deposits in the die of an extrusion apparatus during the extrusion of a second polymeric material, wherein the polymeric material (A) has the formula: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of formula: -O-Ph-Ph-O-Ph-CO-Ph- II and a repeat unit of In the formula, Ph represents a phenylene moiety.

[0106] The polymeric material (A) and the second polymeric material may have any of the suitable features and advantages described above in relation to the first and second aspects. Preferably, the use of this third aspect provides a reduction in the formation of deposits (die draw rolls) on the die of the extrusion apparatus during extrusion, compared to a similar process in which the same second polymeric material is extruded without polymeric material (A). Preferably, the use of this third aspect reduces defects in the extruded product caused by the die draw rolls and / or increases the time that the extrusion process can be carried out before the process needs to be stopped and the deposits on the die removed.

[0107] Typically, die-roll deposits are carbonaceous and therefore electrically conductive, a major drawback in the field of electrical insulation. Suitably, in this third embodiment of the use, the polymeric material (A) is disposed as an outer layer of a second polymeric material. [Brief explanation of the drawings]

[0108] For a better understanding of the present invention, and to show how exemplary embodiments may be practiced, reference is now made to the accompanying drawings. [Figure 1a] 2 is a schematic illustration of an extrusion die for producing an extruded product of the first aspect of the invention in the form of a cable or wire assembly using a method according to the second aspect of the invention; FIG. [Figure 1b]1b is a cross-sectional view of an extruded product produced by the extrusion process of FIG. 1a. [Figure 2a] FIG. 2 is a schematic diagram of an alternative extrusion die for producing an extruded product of the first aspect of the invention in the form of a cable or wire assembly using a method according to the second aspect of the invention. [Figure 2b] 2b is a cross-sectional view of an extruded wire or cable sheath produced by the extrusion process of FIG. 2a. [Figure 3a] FIG. 2 is a schematic diagram of an alternative extrusion die for producing an extruded product of the first aspect of the invention in the form of a cable or wire assembly using a method according to the second aspect of the invention. [Figure 3b] 3b is a cross-sectional view of an extruded wire or cable sheath produced by the extrusion process of FIG. 3a. [Figure 4a] FIG. 2 is a schematic diagram of an extrusion die for producing an extruded product of the first aspect of the invention in the form of a pipe using a method according to the second aspect of the invention. [Figure 4b] FIG. 4b is a cross-sectional view of an extruded pipe produced by the extrusion process of FIG. 4a. [Figure 5a] FIG. 2 is a schematic diagram of an extrusion die for producing an extruded product of the first aspect of the invention in the form of a film using a method according to the second aspect of the invention. [Figure 5b] FIG. 5b is a cross-sectional view of an extruded film produced by the extrusion process of FIG. 5a. [Figure 6a] FIG. 2 is a schematic diagram of an extrusion die for producing an extruded product of the first aspect of the invention in the form of a filament using a method according to the second aspect of the invention. [Figure 6b] FIG. 6b is a cross-sectional view of an extruded filament produced by the extrusion process of FIG. 6a. DETAILED DESCRIPTION OF THE INVENTION

[0109] FIG. 1a shows a pressure extrusion die 100 used to manufacture extruded wire or cable assemblies in a "pressure" extrusion process in which the sheath contacts the wire or cable within the die. The extrusion die includes a die body 1 and a die mandrel 2. The die 100 includes a first channel 101, a second channel 102, a third channel 103, and a die outlet 110. Molten polymer materials A and B are supplied under pressure to the first and second channels during use. Molten polymer material A forms a first (outer) layer of the extruded product having the composition described above for polymer material (A). Molten polymer material B forms a second (inner) layer of the extruded product and is preferably the polymer material (B) described above.

[0110] Through the third channel, a wire or cable 3 is passed for coating with a sheath of polymers A and B. A, B, and 3 are fed through a die 100 to a die exit 110, where polymer material B contacts and coats the wire or cable 3 inside the die, and then polymer material A contacts and coats polymer material B in the die body, continuously producing an extruded product including a wire or cable 3 surrounded by a sheath having a first (outer) layer 111 of A and a second (inner) layer 112 of B. This structure is shown in cross section in FIG. 1b. The formation of this extruded wire or cable assembly is carried out with a reduced amount of die deposit formation (die roll) on the die exit 110, since polymer material A has a lower tendency to form such deposits than a second polymer material B, which may advantageously contain a filler material. Such a filler material preferably improves the dielectric breakdown resistance of polymer material B and, therefore, the dielectric breakdown resistance of the wire or cable sheath. The outer layer of A effectively insulates polymer material B from the high temperature exposed surfaces of the die 100, particularly at the die exit 110, which would cause die draw in polymer material B. Thus, in this arrangement, the extrusion method and extruded product preferably provide an advantageous reduction in die draw compared to similar processes and products.

[0111] FIG. 2a shows an extrusion die 200 formed from a die body 1 and a die mandrel 2. The die 200 includes a first channel 201, a second channel 202, a third channel 203, a fourth channel 204, and a die exit 210 and is used to produce an extruded wire or cable assembly in a "pressure" extrusion process in which a sheath contacts the wire or cable within the die. In use, the first, second, and third channels are supplied with molten polymer materials A, B, and C, respectively. These polymer materials are fed under pressure through the die 200 to the die exit 210 to continuously produce an extruded product including three layers 211, 212, and 213 coaxially arranged around the wire 3, as shown in FIG. 2b, corresponding to the polymer materials fed into channels 201, 202, and 203, respectively.

[0112] Similar to the embodiment of Figure 1a described above, a wire or cable 3 passes through a third channel for coating with a sheath of polymers A, B, and C. A, B, C, and 3 are fed through a die 200 to a die exit 210 where polymer material B contacts and coats the wire or cable 3 inside the die, polymer material C contacts and coats polymer material B, and then polymer material A contacts and coats polymer material C, also inside the die body, to continuously produce an extruded product comprising a wire or cable 3 surrounded by a sheath having an outer layer of A and inner layers of B and C.

[0113] Molten polymer material A forms the outer layer of the extruded product and has the composition described above for polymer material (A), i.e., forms the first layer described herein. Molten polymer material B forms the inner layer of the extruded product and is preferably the polymer material (B) described above for the second layer. Molten polymer material C forms the second inner layer of the extruded product and may be the polymer material (B) described above. Polymer material C preferably contains a filler that improves the dielectric breakdown resistance of polymer material C and, therefore, the dielectric breakdown resistance of the wire or cable sheath. Preferably, polymer material B provides an improved bond between polymer material C and wire 3 than would be achieved if polymer material C were in direct contact with wire 3.

[0114] 1a, the outer layer of A effectively insulates polymeric materials B and C from the exposed high temperature surfaces of the die 200, particularly at the die exit 210, which would otherwise cause die draw in polymeric materials B or C. Thus, this arrangement, extrusion method, and extruded product preferably provides an advantageous reduction in die draw compared to similar processes and products.

[0115] 3a shows a die 300 formed from a die body 1 and a die mandrel 2. The die 300 has a similar arrangement of inputs to the die 200, but is configured as a "tube-on" die to coat the wire or cable 3 with a sheath having a first outer layer (i.e., first layer) 311 of A, an inner layer (i.e., second layer) 312 of B, and a second outer layer (i.e., third layer) 313 of A. The coating of the wire or cable 3 with the sheath occurs outside the die body 300 after the sheath exits the die through the die exit 310. Thus, in such a tube-on process, both the outermost and innermost surfaces of the sheath contact the hot, exposed surface of the die 300 at the die exit 310, and thus there can be a risk of creating die-drawn rolls. The wire or cable thus produced includes three layers 311, 312, and 313 coaxially arranged around wire 3, as shown in FIG. 3b, corresponding to the polymeric materials supplied to channels 301, 302, and 303, respectively. Formation of the sheath from polymeric materials A and B occurs inside the die body as shown, so that the first and second outer layers of A actually insulate polymeric material B from the hot, exposed surfaces of die 300, reducing or eliminating die drool as the sheath exits the die, as discussed above. Similar to the embodiment described in connection with FIGS. 1a-2b, molten polymeric material A has the composition described above for polymeric material (A). Molten polymeric material B forms the inner layer of the extruded product and is preferably polymeric material (B) as discussed above. Polymeric material B preferably contains a filler that provides polymeric material (B) with electrical breakdown resistance.

[0116] FIG. 4a shows an extrusion die 400 for forming a pipe, the die being formed from a die body 1 and a die mandrel 2. The die 400 includes a first channel 401, a second channel 402, a third channel 403, a fourth channel 404, and a die exit 410. Molten polymer material is supplied under pressure through the die 400 to the die exit 410 through the first, second, and third channels during use to continuously produce an extruded pipe product including three layers 411, 412, and 413, as shown in FIG. 4b, which correspond to the polymer materials supplied to channels 401, 402, and 403, respectively. The fourth channel 404 includes a pin 3 for creating a hollow center 414 of the pipe. The molten polymer material supplied to the first channel 401 is the polymer material (A) described above. The molten polymer material supplied to the second channel 402 is the second polymer material described above, for example, the polymer material (B) described above. The molten polymeric material fed into the third channel 403 is the polymeric material (A) described above. Thus, during use, the die 400 produces an extrusion product including an inner layer (i.e., the second layer) of a second polymeric material disposed between two outer layers (i.e., the first and third layers) of polymeric material (A). This extrusion product is formed with a reduced amount of die deposit formation (die drowning) at the die exit 410 because the polymeric material (A) has a lower tendency to form such deposits than the second polymeric material, which may contain a filler material. The two outer layers of polymeric material (A) effectively insulate the second polymeric material from the high-temperature exposed surfaces of the die 400, particularly at the die exit 410, which would otherwise cause die drowning in the second polymeric material. Thus, this arrangement, extrusion method, and extrusion product advantageously provide an advantageous reduction in die drowning compared to similar processes and products.

[0117] FIG. 5a shows an extrusion apparatus 500 for producing extruded film. The apparatus includes a die body 1 and a coextrusion feedblock 2. The coextrusion feedblock 2 is provided with a first channel 501, a second channel 502, and a third channel 503. Under pressure, molten polymer material A is supplied to the first and second channels in use, and polymer material B is supplied to the third channel. These polymer materials are coextruded through the coextrusion feedblock and then passed through a die 1 to be formed into a film having a desired thickness. As shown in FIG. 5b, molten polymer material A from channel 501 forms a first outer layer 511 of the film, molten polymer material A from channel 502 forms a second outer layer 512, and molten polymer material B from channel 503 forms an inner layer 513.

[0118] Similar to the above embodiment, die drool formation is reduced because only the outer layer of polymer material A of the film contacts the coextrusion feedblock 1 and die 2, thus reducing the tendency of polymer material (A) to create die drool.

[0119] FIG. 6a shows a die 600 for producing a filament extrusion product. The die 600 is formed from a die body 1 and a die mandrel 2. The die 600 comprises a first channel 601, a second channel 602, and a die exit 610. In use, the first and second channels are supplied with molten polymer materials A and B under pressure. As shown in FIG. 6b, the molten polymer material A forms an outer layer 611 of the filament having the composition described above for polymer material (A), and the molten polymer material B forms an inner layer or core 612 of the filament. The molten polymer material B is preferably the polymer material (B) described above and preferably includes a filler material.

[0120] Similar to the embodiment described above, only the outer layer of polymer material A of the filament contacts the hot, exposed surface of die 600, and therefore die drool formation is reduced because polymer material (A) has a lower tendency to produce die drool than the polymer material of composition (B), especially when polymer material B includes a filler material. Filaments produced in this manner may be useful as a feedstock in additive manufacturing. [Example]

[0121] The following extrusion products were produced to demonstrate the reduction in die draw that can be obtained with the present invention. The method involves the process steps of drying the polymer and subsequently extruding it into a solid form, during which die-draw roll initiation is compared for a variety of polymers and configurations. Examples of solid forms include polymer filaments, flat wires with polymer coatings, and coextruded round wires with multi-layer polymer coatings.

[0122] Polymer Drying Prior to extrusion, powders / pellets of each of the polymeric materials described and used in the following methods were dried to less than 0.05% w / w moisture (-40°C dew point) by placing the material in an air-circulating oven for a minimum of 3 hours at 150°C or 2 hours at 160°C. For LMPAEK™ materials, the preferred drying time was 2-3 hours at 120°C. To ensure the material is sufficiently dry, the moisture content may be measured according to ISO 15512 Method (B) in accordance with ISO 1133. This drying is to prevent moisture from causing voids in the extrudate after extrusion due to the hygroscopic nature of the polymeric material in powder or pellet form.

[0123] It will be understood that a reference to unfilled PEEK (Victrex 381G) in any one of the following examples includes, but is not limited to, PEEK produced in accordance with WO2018055384.

[0124] Example Set 1 - Filament To evaluate the relative speed of die-roll formation of these polymeric materials, filaments formed of the polymeric materials were produced by continuous extrusion of the molten polymeric material.

[0125] Example 1.1 - A PEEK polymer material manufactured by Victrex Manufacturing Limited under the designation 381TL30 as defined herein, containing 30% by weight of talc (JETFINE™ 3CA) filler material.

[0126] Example 1.2-Unfilled PEEK material manufactured by Victrex Manufacturing Limited under the designation 381G. Example 1.3 - PEEK / PEDEK copolymer manufactured by Victrex Manufacturing Limited as LMPAEK™ material according to European Patent No. 3013888.

[0127] Filament manufacturing method The filaments were produced by introducing pre-dried polymeric material into a typical single-screw extrusion line consisting of a heated extruder barrel with a screw having several zones: a feed zone, a compression zone, a metering zone, and a die zone (see Table 1), each with a temperature of 300-390°C. The polymeric material was fed through the zones to produce molten filaments at the die zone exit. The molten filaments were pulled through the die and cooled below the melting point of the polymeric material, solidifying the filaments into their final form.

[0128] [Table 1]

[0129] The extruder barrel inner diameter was 15 mm to 50 mm, and the screw had a length-to-diameter ratio (L / D) of 16:1 to 28:1, preferably 18:1 to 24:1. The line speed was set at 8 to 8.5 m / min.

[0130] Typically, the screw speed was set at 15 to 25 rpm. The screw speed may vary within the range of 3 to 50 rpm, preferably 4 to 30 rpm, and most preferably 5 to 30 rpm. The line speed may vary within the range of 1 to 30 m / min, preferably 3 to 25 m / min, and most preferably 4 to 20 m / min.

[0131] The melt pressure during extrusion was measured with a pressure transducer that could be placed at the end of the screw or in the die. Melt pressure can vary depending on the type of material and the speed, but is typically in the range of 2 bar up to a maximum of 500 bar.

[0132] The molten polymer material passed through an extrusion line and flowed through a die with a circular opening approximately 4 mm in diameter. The molten material was withdrawn from the die and cooled in air at ambient temperature until it was below the melting point of the material. The solidified filaments were drawn to the desired thickness using a caterpillar-type puller. Filaments approximately 1.5 to 2 mm, typically 1.7 mm, were produced by this process.

[0133] The die openings may vary in size and shape, for example, the openings may have a diameter of 0.2 to 8 mm and may have a square, rectangular, or multilobal profile depending on the desired cross-sectional shape of the extruded product. The length of the die openings is preferably in the range of 0.1 to 6 times the diameter of the extruded filaments, and the introduction section preferably has a smooth, constant change in diameter, although step-wise diameter changes are also possible.

[0134] The filament was extruded through the extrusion line until die draws were visible around the die opening and began to adversely affect the quality of the extruded product. Such adverse effects on the quality of the extruded product include visible marks and defects on the surface of the extruded product. Diameter thinning of the extrudate material, and typically a reduction in diameter or thickness of more than 15% is detrimental to product quality. Amounts less than 15% are understood to be acceptable by those skilled in the art. Additionally, carbonaceous die draws that separate from the die and adhere to the extrudate can adversely affect the quality of the final product. The time elapsed from the start of extrusion to the time of the formation of adverse die draws is detailed in Table 2 for different polymeric materials.

[0135] [Table 2]

[0136] The results in Table 2 show that the PEEK / PEDEK material provides a significant improvement in the time elapsed before die-roll forming causes visible defects along the length of the extrudate compared to using filled PEEK material or PEEK alone. In doing so, the extrusion process of the present invention can be run for extended periods of time before the process must be stopped and the extrusion equipment cleaned. Advantageously, the present process results in a more efficient manufacturing process, resulting in longer product lengths.

[0137] Example 2 - Coated Wire The coated wire was formed by extruding the polymeric material listed above in Table 2 onto a copper wire as a single layer. Again, this process used continuous extrusion of molten polymeric material onto a wire to evaluate the relative speed of die-draw forming of the polymeric material.

[0138] The coated wire was extruded through a clean extrusion die until significant die draw was visible around the die opening and began to adversely affect the quality of the extruded product. Such adverse effects on extruded product quality include visible markings and defects on the surface of the extruded product. The time elapsed from the start of extrusion to the point of die draw formation was recorded and is shown in Table 3 for different polymer materials. The coated wire was produced using the method and apparatus described below.

[0139] Method - Coated Wire Coated wire was produced using an extrusion line with the barrel diameter ratio and line speed described above for Example 1. The screw speed was typically set at 2-10 rpm. To produce the coated wire, the extrusion line was configured with a crosshead die through which the polymer melt entered from the side of the line. This configuration allowed the polymer material to contact the wire within the die and form a sheath. This type of extrusion process is sometimes referred to as a "pressure" or "pressure die" system. In this example, the wire was a copper wire with a rectangular cross section. The wire was continuously fed through the extrusion line, and the polymer material was extruded onto the wire in a continuous process. The line speed was set at 8-8.5 m / min.

[0140] The cross-sectional shape of the wires may vary, for example, they may be square or rectangular, and the aspect ratio of rectangular wires may be 4:1 or less. The gap between the uncoated wire and the die opening is typically 50 to 300 micrometers. The final coated wire had a thickness of 100 to 200 micrometers.

[0141] Table 3 below shows the results for time to die roll.

[0142] [Table 3]

[0143] The results in Table 3 show that using PEEK / PEDEK material as a single polymer layer on the wire that contacts the extrusion die during the extrusion process increases the time before significant die drool develops and begins to adversely affect the quality of the extruded product. In contrast, filled and unfilled PEEK materials demonstrate faster die drool formation than PEEK / PEDEK materials. Therefore, the use of PEEK / PEDEK allows the extrusion process to continue for a longer period of time before it is necessary to stop and clean the extrusion equipment. This can provide a more efficient manufacturing process and a longer extruded product.

[0144] Example 3 - Coextrusion over a wire Wires having inner and outer layer coatings of polymeric materials as shown in Figures 1a and 1b were formed by extruding the polymeric materials shown below in Table 4 as the outer and inner layers onto copper wire. Again, this process used continuous extrusion of molten polymeric material onto the wire to evaluate the relative speed of die-draw forming of these polymeric materials.

[0145] [Table 4]

[0146] The coated wire was again extruded through a clean extrusion die, as described above in connection with Figures 1a and 1b, until a die draw was visible around the die opening and began to adversely affect the quality of the extruded product. Such adverse effects on the quality of the extruded product include visible marks and defects on the surface of the extruded product. The time elapsed from the start of extrusion to the point at which the die draw formed, causing the quality defects described above, was recorded and is shown in Table 5 for different polymer materials. The coated wire was produced using the method and apparatus described below.

[0147] The coated wire was produced using the extrusion line described above with a second heated extruder barrel for the second polymeric material. The extrusion die used was of the type shown in Figure 1a, configured for a "pressure" extrusion process, in which the outer and inner layer polymeric materials form a sheath on the wire within the die, with the outer layer contacting the die and the inner layer contacting the wire in the product as it exits. The polymeric material described in Table 4 was extruded through first channel 101 and second channel 102, as described above and shown in the figure, to form the outer and inner layers, respectively, on the wire.

[0148] [Table 5]

[0149] The results in Table 5 show that a multilayer extruded product having a polymeric material (A), a PEEK / PEDEK copolymer claimed in the present invention, as an outer layer coating contacting the surface of the extrusion die at exit from the die can significantly increase the time before die drool forms and begins to adversely affect the quality of the extruded product, compared to similar filled or unfilled PEEK materials. The use of a PEEK / PEDEK material as the outer layer provided approximately a 12-fold improvement in the time elapsed before significant die drool formation, compared to the use of a filled PEEK material as the outer layer.

[0150] Advantageously, the extrusion process for forming products comprising PEEK / PEDEK can continue for a longer period of time before the process needs to be stopped to clean the extrusion equipment, thereby providing a more efficient manufacturing process. Furthermore, the process may be run at higher output or line speeds that would normally result in poor die-drawing, thereby improving productivity as well as product quality. Thus, such extrusion products can be formed with an inner layer comprising a PEEK polymer and a filler material without the polymer and filler material adversely affecting the process and product due to excessive die-drawing.

[0151] It will be apparent to those skilled in the art that the advantages seen in the above examples can also be applied to other wire coating embodiments, as described and shown in the figures herein, and to multilayer film and pipe embodiments.

[0152] While several preferred embodiments have been shown and described, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims.

[0153] Throughout this specification, the terms "comprising" or "comprise" mean including the specified component(s), but do not exclude the presence of other components. The terms "consisting essentially of" or "consist essentially of" mean including the specified component(s), but excluding other components, excluding materials present as impurities, unavoidable materials present as a result of the process used to provide the component, and components added for purposes other than achieving the technical effect of the invention. Typically, when referring to a composition, a composition consisting essentially of a set of components will contain less than 5% by weight, typically less than 3% by weight, and more typically less than 1% by weight of the unspecified component(s).

[0154] The terms "consisting of" or "consist of" mean the inclusion of the specified components, but the exclusion of additional components. Wherever appropriate and depending on the context, use of the words "comprise" or "comprising" may be interpreted as including or including the meaning of "consist essentially of" or "consisting essentially of" and may also be interpreted as including the meaning of "consist of" or "consisting of."

[0155] For the avoidance of doubt, when the amount of a component in a composition is stated in weight %, this refers to the weight percentage of the particular component relative to the entire composition being referred to. For example, "polymeric material (A) provides 70-100% by weight of the outer layer" means that 70-100% by weight of the outer layer is provided by polymeric material (A).

[0156] Any features described herein can be used individually or, where appropriate, in combination with one another, particularly in the combinations set forth in the appended claims. Optional features for each aspect or exemplary embodiment of the present invention described herein should also be read as applicable to any other aspect or exemplary embodiment of the present invention, where appropriate. In other words, those skilled in the art reading this specification should consider optional features for each exemplary embodiment of the present invention to be interchangeable and combinable between different exemplary embodiments.

[0157] Attention is directed to all articles and documents related to this application, filed contemporaneously or previously hereto, and open to public inspection herewith, the contents of all such articles and documents being incorporated herein by reference.

[0158] All of the features disclosed in this specification (including any accompanying claims and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations in which at least some of such features and / or steps are mutually exclusive.

[0159] Each feature disclosed in this specification (including any accompanying claims and drawings), unless expressly stated otherwise, may be replaced by alternative features serving the same, equivalent, or similar purpose. Thus, unless expressly stated otherwise, each feature disclosed is only an example of a generic series of equivalent or similar features.

[0160] The invention is not limited to the details of the foregoing embodiment(s). The invention extends to any novel one or any novel combination of features disclosed in this specification (including any accompanying claims and drawings), or any novel one or any novel combination of steps of any method or process so disclosed.

Claims

1. 1. An extruded article comprising a first layer and a second layer, the first layer comprising a polymer having the formula: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of formula: -O-Ph-Ph-O-Ph-CO-Ph- II and a polymer material (A) having a repeating unit of wherein Ph represents a phenylene moiety.

2. 10. The extruded product of claim 1, wherein the first layer is an outer layer and the second layer is an inner layer.

3. The extruded product of claim 1 or 2, wherein the second layer comprises a filler material.

4. 4. The extruded product of any one of claims 1 to 3, wherein the filler material is a particulate filler material.

5. The second layer has the formula: -O-Ph-O-Ph-CO-Ph- I a polymer material (B) having a repeating unit of 5. The extruded product of any one of claims 1 to 4, wherein Ph represents a phenylene moiety.

6. a third layer, wherein the second layer is disposed between the first layer and the third layer, and the third layer has the formula: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of formula: -O-Ph-Ph-O-Ph-CO-Ph- II and a polymer material (A) having a repeating unit of 6. The extruded product of any one of claims 1 to 5, wherein Ph represents a phenylene moiety.

7. The extruded product of any one of claims 1 to 6, wherein the first layer and / or the third layer comprises a release agent.

8. The extruded product of any one of claims 1 to 7, wherein the extruded product is in the form of a film.

9. The extruded product according to any one of claims 1 to 7, wherein the extruded product is in the form of a pipe or a cable jacket / sheath.

10. The extruded product of any one of claims 1 to 7, wherein the extruded product is in the form of a filament.

11. The polymeric material (A) has the formula Ia: 【Chemistry 1】 and a repeating unit of Formula IIa: 【Chemistry 2】 and a repeat unit of at least 95 mole % of the repeat units are repeat units of formula Ia and formula IIa; 11. The extruded product of any one of claims 1 to 10, wherein the repeat units Ia and IIa have a molar ratio Ia:IIa of 50:50 to 95:

5.

12. The polymeric material (A) has the formula I: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of Formula IIa: 【Transformation 3】 and a terminal unit, the molar ratio of the repeating units of formula I to the repeating units of formula IIa is 50:50 to 95:5; The repeating units of formula I are 50 to 90 mole % of formula Ia: 【Chemistry 4】 and 10 to 50 mole % of repeat units of formula Ib, repeat units of formula Ic, or a mixture thereof; The repeat unit of formula Ib is 【Transformation 5】 and The repeat unit of formula Ic is 【Transformation 6】 The extruded product according to any one of claims 1 to 10,

13. 1. A method of manufacturing a product comprising a first layer and a second layer, the method comprising: a) Formula: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of formula: -O-Ph-Ph-O-Ph-CO-Ph- II and providing a source of polymeric material (A) having repeat units of the formula: b) providing a source of a second polymeric material; c) delivering the polymeric material (A) and the second polymeric material to an extrusion station comprising a die; and d) extruding said polymeric material (A) and said second polymeric material through said die such that said polymeric material (A) contacts said die during extrusion and said second polymeric material does not contact said die during extrusion to form an extruded product.

14. The method of claim 13 , wherein the second polymeric material comprises a filler.

15. 15. The method according to claim 13 or claim 14, wherein the method is carried out continuously for at least 5 hours, preferably at least 10 hours.

16. 1. Use of a polymeric material (A) for reducing the formation of deposits on the die of an extrusion apparatus during the extrusion of a second polymeric material, said polymeric material (A) having the formula: -O-Ph-O-Ph-CO-Ph- I and a repeating unit of formula: -O-Ph-Ph-O-Ph-CO-Ph- II and a repeat unit of In the formula, Ph represents a phenylene moiety.

17. 17. The use according to claim 16, wherein the polymeric material (A) is disposed as an outer layer of the second polymeric material.

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