Polymer compositions based on poly(ether ketone ketone) and thermoplastic polyimide with a high glass transition temperature

Abstract

The invention relates to a composition comprising: a poly(ether ketone ketone), PEKK1; a thermoplastic polyimide having a glass transition temperature greater than or equal to 230°C, TPI; and optionally, a poly(aryl ether ketone), PAEK, PAEK being distinct from PEKK1. PEKK1 represents at least 50% by weight, relative to the total weight of PEKK1, TPI and, where applicable, PAEK, of the composition. PAEK is necessarily present when the TPI content is greater than or equal to 20% by weight, and preferably when the TPI content is greater than or equal to 15% by weight, relative to the total weight of PEKK1 and TPI of the composition.

Description

[0001] Description

[0002] Title: Polymer compositions based on poly(ether ketone ketone) and thermoplastic polyimide with high glass transition temperature

[0003] Scope of the invention

[0004] The present invention relates to the field of polymer materials, and more particularly to compositions based on poly(etherketone ketone) (PEKK) and thermoplastic polyimides. These compositions are designed to meet the requirements of advanced industrial sectors, including aerospace, automotive, medical, and offshore drilling.

[0005] Prior art

[0006] Poly(etherketone ketones) are well-known, high-performance engineering polymers. They can be used in demanding applications involving high temperatures and / or high mechanical, and even chemical, stresses. They can also be used in applications requiring excellent fire resistance and low emissions of smoke or toxic gases. Finally, they exhibit good biocompatibility. These polymers are found in fields as diverse as aerospace, offshore drilling, automotive, rail, marine, wind energy, sports, construction, electronics, and medical implants. Despite these advantageous properties, it is sometimes necessary to formulate poly(etherketone ketones) to meet specific requirements. In particular, increasing the glass transition temperature of the material can broaden the temperature range over which it can be used.This allows the material to retain good mechanical properties even at higher temperatures. Furthermore, it is important that the formulation remains stable over time at these higher temperatures. In the present invention, the inventors focused on performing mechanical tests after subjecting the materials to prolonged heat treatment at 250°C, which could, for example, be representative of extended use at such a service temperature.

[0007] Mixtures of poly(aryl ether ketone) (PAEK) and poly(bisphenol A-co-4-nitrophtal anhydride-co-1,3-phenylenediamine) (PEI), and mixtures of poly(aryl ether ketone) (PAEK) and poly(phenylsulfone) (PPSU) are well known and have been extensively studied. The addition of PEI and / or PPSU generally increases the glass transition temperature of PAEK.

[0008] Document WO23242364 discloses mixtures of PEKK and PEI. Document WO20095268 discloses mixtures of PEEK and PEI. PEI is known to be miscible with poly(ether ether ketones) (PEEK) and with PEKK, even in high proportions of PEI. However, the glass transition temperature of PEI is 217°C, which is insufficient to significantly raise the glass transition temperature of the mixture. Furthermore, the inventors have demonstrated in the present invention that such a material does not retain its mechanical properties after aging at 250°C.

[0009] Prior art also discloses other thermoplastic polyimides besides PEI. Thermoplastic polyimides are polymers characterized by the presence of imide (-CO-N-CO-) bonds in their molecular structure. Document WO2024014123 discloses in Table 2 PEKK compositions with polyimides having glass transition temperatures ranging from 166°C to 233°C (Table 1). The glass transition temperatures are defined for a second heating with a heating rate of 20°C / min and a cooling rate of 10°C / min. As with PEI, these glass transition temperatures remain too low, even assuming that these less common polyimides are miscible with PEKK, for the glass transition temperature (Tg) of the material to be sufficiently increased.

[0010] Document EP2899231 describes a phase-separated polymer blend composed of 25 to 85% by weight of a polyetherimide and 15 to 75% by weight of a PAEK. The polymer blend is used in a composite material that also includes a fibrous filler and a mineral filler. The document specifically discloses blends of PEEK and polyimides from the Aurum® range. According to the corresponding technical brochure, the glass transition temperature of polymers in this range is around 250°C. Although the glass transition temperature of this type of polyimide is sufficiently high, the immiscibility of PEEK and this type of polyimide prevents an increase in the glass transition temperature of the polymer blend. Indeed, the immiscibility of PEEK with Aurum® means that the blend has an initial glass transition temperature corresponding to that of PEEK.It can also be pointed out that the material according to EP2899231 contains as an essential characteristic a fibrous filler material and a mineral filler material, necessary to ensure good mechanical properties of the material.

[0011] Furthermore, a general problem with blends of a semi-crystalline polymer with any other polymer, amorphous or semi-crystalline, is that the other polymer tends to disrupt the crystalline phases of the semi-crystalline polymer, resulting in a slower crystallization rate of the semi-crystalline polymer in the blend. Therefore, a challenge when formulating a blend of poly(etherketoneketone) and polyimide is to maintain a crystallization rate comparable to that of poly(etherketoneketone) alone, so that the blend can be used in the same processing methods and under conditions comparable to those of poly(etherketoneketone) alone.For example, a problem when formulating a mixture of poly(ether ketone ketone) and polyimide may be to maintain a good crystallization rate so that the mixture can be used in a process with a fast implementation cycle, particularly in an injection molding process.

[0012] Summary of the invention

[0013] The present invention relates to a composition comprising:

[0014] • a poly(ether ketone ketone), PEKK1;

[0015] • a thermoplastic polyimide having a glass transition temperature greater than or equal to 230 °C, TPI; and

[0016] • optionally, a poly(aryl ether ketone), PAEK, PAEK being distinct from PEKK1; in which: o PEKK1 represents at least 50% by weight, relative to the total weight of PEKK1, TPI and where applicable PAEK, of the composition, and o PAEK is required to be present when the TPI content is greater than or equal to 15% by weight, relative to the total weight of PEKK1 and TPI of the composition.

[0017] The TPI content is between 5% and 30% by weight, and is less than or equal to 25% by weight, relative to the total weight of PEKK1 and TPI in the composition.

[0018] When PAEK is present in the composition, its content represents from 0.1% to 20% by weight, relative to the total weight of PEKK1, TPI and PAEK in the composition

[0019] Advantageously, TPI does not include sulfone and / or isopropyl idene groups.

[0020] Advantageously, PEKK1 comprises terephthalate (T) and isophthalate (I) units, with a T:I molar ratio ranging from 55:45 to 89:11, and preferably from 72:28 to 85:15. Advantageously, PAEK, when present in the composition, is selected from:

[0021] • a poly(ether ether ketone), PEEK;

[0022] • a poly(ether ketone), PEK;

[0023] • a poly(ether ketone ether ketone ketone), PEKEKK;

[0024] • a poly(ether ketone ketone) having a T / l ratio higher than that of PEKK1 and / or a lower viscosity index than that of PEKK1, PEKK2; and • any mixture of at least two of these polymers.

[0025] According to another embodiment, PAEK is PEEK.

[0026] Advantageously, when PAEK is present in the composition, its content represents from 1% to 18% by weight, and more preferably from 5% to 15% by weight, relative to the total weight of PEKK1, TPI and PAEK in the composition.

[0027] Advantageously, the TPI includes repeating units of general formula (I)

[0028] [Chem 1] in which:

[0029] •X represents a monocyclic or polycyclic tetravalent group, saturated, unsaturated or aromatic, substituted or unsubstituted, comprising from 5 to 50 carbon atoms and possibly one or more heteroatoms; and

[0030] • Ri represents a linear, branched or cyclic divalent radical, substituted or unsubstituted, comprising from 2 to 50 carbon atoms, preferably from 6 to 36 carbon atoms, and possibly comprising one or more heteroatoms.

[0031] Preferably, in formula (I), Ri corresponds to the general formula (III): [Chem 2]

[0032] (III). in which Q represents a direct bond or a radical selected from the group consisting of -O-, -C(O)-, -OYO-, alkylenes comprising 1 to 6 carbon atoms, and cycloalkylenes comprising 4 to 8 carbon atoms, where Y represents a group of general formula (II IA) or (II IB):

[0033] [Chem 3] (HIA), [Chem 4]

[0034] (IIIB), in which Z represents a direct bond or a radical selected from the group consisting of -O-, -C(O)-, alkylenes comprising 1 to 6 carbon atoms, and cycloalkylenes comprising 4 to 8 carbon atoms, and for formulas (II), (IIIA) and (IIIB), in which each group Rj, Rk, Ri, RO and R Pis, independently of each other, a hydrocarbon group comprising from 1 to 10 carbon atoms and possibly including one or more heteroatoms, each index j, k, I, o and p being an integer from 0 to 4 and representing a number of substitution groups on a ring.

[0035] According to a preferred embodiment, the TPI comprises repeating units of general formula (IV):

[0036] [Chem 5]

[0037] According to another preferred embodiment, the TPI comprises repeating units of general formula (V):

[0038] [Chem

[0039] According to one embodiment, the composition described above, and in more detail below, further comprises one or more fillers and / or one or more functional additives.

[0040] The invention also relates to an article made from the composition as described above and in detail below.

[0041] The invention also relates to a method for manufacturing said article, the method comprising at least one step of injection molding or extrusion of a composition according to the invention. The Applicant has developed polymer blends comprising a PEKK (referred to in the invention as PEKK1) as the main polymer, a polyimide having a glass transition temperature (Tg) greater than or equal to 230°C (referred to in the invention as TPI), and in certain embodiments a poly(aryl ether ketone) distinct from PEKK1 (referred to in the invention as PAEK). These blends offer significant advantages in terms of good polymer miscibility, thermal stability, and crystallization rate.

[0042] The Applicant observed that PEKK offers significantly better miscibility with TPI than PEEK at an equivalent TPI ratio. Therefore, by selecting a polyimide with a glass transition temperature (Tg) of 230°C or higher, the resulting mixture has a glass transition temperature that ensures good mechanical properties up to higher operating temperatures.

[0043] Furthermore, the compositions according to the invention are thermally stable and retain their mechanical properties, even after high-temperature aging, for example at 250°C or higher. In particular, these compositions are more stable than comparative compositions comprising PEKK1 and a polyimide having a lower glass transition temperature than the TPIs according to the invention.

[0044] This precise choice of polymers – PEKK1 as the main component, TPI, and possibly PAEK – optimizes polymer compatibility, crystallization, and the thermal stability of the mixture. It also ensures good processability of the mixture.

[0045] Detailed description

[0046] Definitions:

[0047] The miscibility of the polymers of the invention refers to the ability of two or more polymers to mix homogeneously at the molecular level to form a single phase. When two polymers are miscible, they interact well enough to prevent phase separation.

[0048] Miscibility can be assessed by the presence of a single glass transition temperature (Tg) in a mixture. If a single Tg peak is observed, this indicates that the polymers are miscible and form a homogeneous phase. Conversely, if two distinct Tg peaks appear, this means that the polymers are immiscible or partially miscible, forming distinct phases within the material.

[0049] A glass transition temperature (Tg) is the temperature at which a polymer changes from a rigid, glassy state to a more flexible, rubbery state. The Tg(s) are generally determined using techniques such as dynamic mechanical analysis (DMA) or differential scanning calorimetry (DSC).

[0050] The glass transition temperature (Tg) of a single polymer, particularly TPI, is preferably determined by DSC, according to ISO 11357-2:2020. It is measured at mid-height of the glass transition on the thermogram carried out under a nitrogen atmosphere and in a second heating according to the following thermal cycle:

[0051] - heats at 10°C / min up to a temperature typically about 30°C above the extrapolated final melting temperature (for Aurum® PL500A and Aurum® PL450C, about 420°C);

[0052] - cooling at 20°C / min up to a temperature of 20°C;

[0053] - temperature plateau at 20°C for 5 min;

[0054] - heats at 10°C / min up to a temperature typically about 30°C above the extrapolated final melting temperature (for Aurum® PL500A and Aurum® PL450C, about 420°C).

[0055] The Tg of a polymer blend, or where applicable the single Tg of a polymer blend, in particular that of the polymer blend(s) of the compositions according to the invention or that of the compositions according to the invention comprising such blends, is preferably determined by DMA, according to ISO 6721-11. The Tg of a single semi-crystalline polymer can also be determined by DMA, in particular for the purpose of comparison with the Tg or Tgs of a polymer blend comprising this semi-crystalline polymer as a constituent. Type 1A dumbbells (see ISO 527-2:2012) obtained by injection molding, then dried for 24 hours at 130°C, and finally heat-treated for 4 hours at 260°C are used for this measurement. This measurement is performed under a nitrogen atmosphere following this thermal profile: cooled to 0°C, temperature maintained at 0°C for 10 minutes, then heated at 2°C / min. The Tg(DMA) or the T g(DMA) correspond to the maximum(s) of the tangent of the phase angle delta (noted tan 5, corresponding to the ratio viscous modulus / elastic modulus, noted E” / E’) at 1 Hz.

[0056] A semi-crystalline polymer is a polymer that possesses, or is capable of possessing, crystalline domains. Crystalline domains form when polymer chains align in an ordered manner, creating regular structures called crystallites. However, if cooling is rapid, crystallization may not occur, and the polymer remains in an amorphous state.

[0057] The crystallization temperature (Te) corresponds to the temperature at which polymer chains begin to organize into crystalline structures upon cooling from the molten state. Te is preferably measured by DSC under a nitrogen atmosphere. It corresponds to the peak temperature of the exotherm on the thermogram recorded during the first cooling, according to the following thermal cycle:

[0058] - heats at 20°C / min up to 420°C;

[0059] - first cooling at 20°C / min or 60°C / min up to a temperature of 20°C (measurement of Te);

[0060] - temperature plateau at 20°C for 5 min;

[0061] - second heating at 20°C / min up to 420°C (measurement of the enthalpy of fusion in the second heating).

[0062] In this invention, the Te is used to compare the expected crystallization rates of one polymer or polymer blend with another polymer or polymer blend. A higher Te generally indicates that the polymer or polymer blend will begin to crystallize earlier upon cooling. An alternative or complementary way to assess the crystallization rate is to measure the enthalpy of fusion during the second heating. A higher enthalpy of fusion generally indicates that the polymer or polymer blend crystallizes more during the first cooling and / or the initial part of the second heating.

[0063] In this description, unless otherwise stated, any range of numeric values ​​expressed by a lower and upper limit explicitly includes those limits, as well as all intermediate values ​​and subranges between them. For example, a range from "X to Y" means that the value can be X, Y, or any value in between.

[0064] The PEKK1

[0065] The composition of the present invention comprises more than 50% by weight of poly(etherketone ketone). In the invention, this poly(etherketone ketone) is referred to by the abbreviation PEKK1. Thus, the composition of the present invention comprises more than 50% by weight of PEKK1, relative to the total weight of PEKK1, TPI, and, where applicable, PAEK, in the composition.

[0066] Preferably, the composition comprises at least 55% by weight of PEKK1, preferably between 60% and 95% by weight, and more preferably between 70% and 90% by weight, relative to the total weight of PEKK1, TPI, and, where applicable, PAEK in the composition. Advantageously, PEKK1 is essentially composed of, or composed of, repeating units derived from terephthaloyl chloride and isophthaloyl chloride, which form terephthalate (T) and isophthalate (I) units, respectively, in the polymer chain. These units are based on phenylene groups linked by ether and ketone bonds.

[0067] Terephthalate (T) units comprise a 1,4-phenylene group, and can be represented by the following formula (VI):

[0068] [Chem 7]

[0069] Isophthalate (I) units comprise a 1,3-phenylene group, and can be represented by the following formula (VII):

[0070] [Chem 8]

[0071] The molar ratio of T / l units in PEKK1 can vary between 20:80 and 80:20. In some embodiments, this molar ratio T / l is preferably between 55:45 and 89:11, and more specifically between 72:28 and 85:15.

[0072] Preferably, PEKK1 has a glass transition temperature between 150 °C and 180 °C, preferably between 160 °C and 170 °C.

[0073] Advantageously, PEKK1 has a viscosity index at 25 °C, in an aqueous solution of sulfuric acid at 96% by mass, according to ISO 307:2019 applied to a poly(aryl ether ketone), of 0.5 to 2.0 dl / g, and preferably of 0.7 to 1.4 dl / g.

[0074] The TPI

[0075] The thermoplastic polyimide used in the composition according to the invention has a glass transition temperature, Tg, greater than or equal to 230°C. In the invention, this thermoplastic polyimide is referred to by the abbreviation TPI. The Tg of the TPI polymer alone is determined by differential scanning calorimetry (DSC) in a second heating cycle with heating ramps of 10°C / min and a cooling ramp of 20°C / min, under a nitrogen atmosphere, and corresponds to the value at half the glass transition temperature.

[0076] According to some preferred embodiments, the TPI has a glass transition temperature greater than or equal to 240°C. According to some preferred embodiments, the TPI may have a glass transition temperature greater than or equal to 245°C, or even greater than or equal to 250°C. The TPI represents between 5% and 40% by weight, and preferably between 10% and 30% by weight, relative to the total weight of PEKK1 and TPI in the composition according to the invention. The TPI content is less than or equal to 25% by weight, relative to the total weight of PEKK1 and TPI in the composition according to the invention.

[0077] Thus, the TPI content is 5% to 25% by weight, including terminals, relative to the total weight of PEKK1 and TPI of the composition according to the invention.

[0078] According to some embodiments, the TPI content is greater than or equal to 6%, or greater than or equal to 7%, or greater than or equal to 8% by weight, or greater than or equal to 9% by weight relative to the total weight of PEKK1 and TPI of the composition according to the invention.

[0079] According to some embodiments, the TPI content is less than or equal to 24%, or less than or equal to 23%, or less than or equal to 22% by weight, or less than or equal to 21% by weight relative to the total weight of PEKK1 and TPI of the composition according to the invention.

[0080] According to some embodiments, the TPI content is 5% to 8% by weight, or 8% to 13% by weight, or 13% to 18% by weight, or 18% to 21% by weight, or 21% to 23% by weight, or 23% to 25% by weight, inclusive of terminals, relative to the total weight of PEKK1 and TPI of the composition according to the invention.

[0081] Advantageously, the TPI includes repeating units corresponding to the general formula (I):

[0082] [Chem 9] in which

[0083] • X represents a monocyclic or polycyclic tetravalent group, saturated, unsaturated, or aromatic, comprising from 5 to 50 carbon atoms; and possibly one or more heteroatoms such as oxygen, nitrogen, or sulfur, and

[0084] • R1 represents a linear, branched or cyclic divalent radical, substituted or unsubstituted, comprising from 2 to 50 carbon atoms, preferably from 6 to 36 carbon atoms, and possibly one or more heteroatoms such as oxygen, nitrogen or sulfur.

[0085] Advantageously, the repeating units of the TPI do not include sulfone (-SO2-) or isopropylidene (-C(CHs)2-) groups. Advantageously, the TPI comprises at least 50% by weight, preferably at least 70% by weight, and preferably a further 90% by weight of repeating units of formula (I).

[0086] According to one embodiment, the TPI consists essentially of repetitive formula units (I).

[0087] According to one embodiment, X comprises less than 30 carbon atoms, preferably less than 20 carbon atoms, and even more preferably less than 18 carbon atoms.

[0088] Advantageously, X does not include an isopropylidene group.

[0089] According to one variant, X is a benzene ring.

[0090] In a second variant, X is an aromatic polycyclic group comprising 10 to 18 carbon atoms.

[0091] According to this second variant, X is preferably chosen from biphenyl, benzophenone, chrysene, phenanthrene, naphthalene or anthracene, possibly substituted.

[0092] According to a preferred embodiment, X is a biphenyl.

[0093] According to another preferred embodiment, X is a benzophenone.

[0094] Advantageously, Ri is a monocyclic or polycyclic group, saturated, unsaturated, or aromatic, comprising from 6 to 36 carbon atoms; and may include one or more heteroatoms such as oxygen, nitrogen, and / or sulfur. Advantageously, Ri does not include a sulfone group.

[0095] Advantageously, Ri comprises fewer than 30 carbon atoms, preferably fewer than 24 carbon atoms, and even more preferably fewer than 18 carbon atoms.

[0096] According to a first variant, Ri corresponds to the general formula (II): [Chem 10] in which Ri represents one or more hydrocarbon groups comprising from 1 to 20 carbon atoms, possibly including one or more heteroatoms, the index i being an integer from 0 to 4 representing the number of substitution groups on a ring. Preferably, i is equal to 0.

[0097] Advantageously, according to this first variant, the bonds between the Ri group and the imide groups in the repeating unit of the TPI are in position 1,3 or 1,4 of the cycle of formula (II).

[0098] According to a second variant, Ri corresponds to the following general formula (III): [Chem 11] O. Q .

[0099] RJ RK

[0100] (III) in which Q represents a direct bond or a radical selected from the group consisting of -O-, -C(O)-, -OYO-, alkylenes comprising from 1 to 6 carbon atoms, and cycloalkylenes comprising from 4 to 8 carbon atoms, where Y represents a group of general formula (II IA) or (II IB): [Chem 12]

[0101] H \ 1 /

[0102] (It AI)

[0103] [Chem 13] in which

[0104] •Z represents a direct bond or a radical selected from the group consisting of -O-, -C(O)-, alkylenes comprising 1 to 6 carbon atoms, and cycloalkylenes comprising 4 to 8 carbon atoms, and

[0105] •each group Rj, Rk, Ri, Ro and R Pis a hydrocarbon group comprising from 1 to 10 carbon atoms and possibly including one or more heteroatoms, each index ], k, I, o and p being an integer from 0 to 4 and representing a number of substitution groups on a ring.

[0106] Advantageously, according to this second variant, the bonds between the Ri group and the imide groups in the repeating unit of the TPI are in meta or para position of the cycles of the general formula (III).

[0107] According to a preferred embodiment of the invention, the TPI comprises, preferably consists essentially of, repeating units of general formula (IV):

[0108] [Chem 14] (IV). Examples of TPIs having such a structure include polymers available under the trade name AURUM® (Mitsui Chemicals).

[0109] According to another preferred embodiment of the invention, the TPI comprises, preferably consists essentially of, repeating units of formula (V): [Chem 15]

[0110] Examples of TPIs with such a structure include polymers available under the trade name TPI Lare (NASA).

[0111] Advantageously, the TPI used in this invention has a molecular weight suitable for the requirements of industrial processes such as injection molding or extrusion.

[0112] PEKK1 is completely miscible up to a TPI content of at least 20% by weight, relative to the total weight of PEKK1 and TPI. This miscibility results in the presence of a single glass transition temperature.

[0113] Advantageously, the glass transition temperature of the composition comprising PEKK1 and TPI according to the invention is higher than that of PEKK1, polymer alone, and lower than that of TPI, polymer alone.

[0114] Advantageously, the glass transition temperature of the composition comprising PEKK1 and TPI according to the invention is higher than that of PEKK1 by at least 2°C, preferably higher by at least 5°C, and preferably even higher by at least 10°C.

[0115] The PAEK

[0116] According to one embodiment, the composition of the invention comprises PEKK1, TPI, and a poly(aryl ether ketone) distinct from PEKK1. In the invention, this poly(aryl ether ketone) distinct from PEKK1 is referred to by the abbreviation PAEK. The addition of this PAEK is particularly advantageous at high TPI concentrations for increasing the crystallization rate of the composition. More specifically, the composition according to the invention and according to these embodiments, comprising PEKK1, TPI, and PAEK, makes it possible to obtain a composition having a higher crystallization rate than a reference composition comprising only PEKK1 and TPI, at the same proportion of TPI relative to the total weight of TPI and total poly(aryl ether ketone) in the composition (i.e., in particular, PEKK1 for the reference composition and PEKK1 and PAEK for the composition according to the invention).PAEK is mandatory in the composition according to the invention when the TPI content is greater than or equal to 15% by weight, relative to the total weight of PEKK1 and TPI in the composition.

[0117] In some embodiments, the composition includes PAEK when the TPI content is greater than or equal to 10% by weight, relative to the total weight of PEKK1 and TPI in the composition. The composition may also include PAEK when the TPI content is less than or equal to 10% by weight, relative to the total weight of PEKK1 and TPI in the composition. However, in these embodiments, the need to increase the crystallization rate of the composition is generally less pronounced.

[0118] The PAEK used advantageously has a higher crystallization temperature than the PEKK1 polymer alone.

[0119] According to one embodiment, the PAEK is chosen from:

[0120] - a poly(ether ether ketone) (PEEK);

[0121] - a poly(ether ketone) (PEK);

[0122] - a poly(ether ketone ether ketone ketone) (PEKEKK);

[0123] - a poly(ether ketone ketone) (PEKK2) having a higher T / l ratio than PEKK1 and / or a lower viscosity index than PEKK1; and

[0124] - any mixture of at least two of these polymers.

[0125] These PAEK polymers can be used alone or in mixtures to vary the mechanical properties and / or the crystallization rate of the composition.

[0126] For the present invention, the term "PEEK" designates a polymer in which more than 50% by moles, preferably more than 75% by moles, and even more preferably more than 90% by moles of the repeating units are repeating units corresponding to formula (VIII):

[0127] [Chem 16]

[0128] L 'o Q o Q Î O - , ' - , s - , J n (V |||)

[0129] For the present invention, the term "PEK" designates a polymer in which more than 50% by moles, preferably more than 75% by moles, more preferably still more than 90% by moles of the repeating units are repeating units corresponding to formula (IX):

[0130] [Chem 17] For the present invention, the term "PEKEKK" designates a polymer in which more than 50% by moles, preferably more than 75% by moles, more preferably still more than 90% by moles of the repeating units are repeating units corresponding to the formula (X): [Chem 18]

[0131] PAEK can also be a poly(ether ketone ketone) distinct from PEKK1, and denoted in the present invention as PEKK2.

[0132] PEKK2 may have a higher T / l ratio than PEKK1. According to some embodiments, PEKK1 may comprise terephthalate (T) units and isophthalate (I) units and a T:l molar ratio ranging from 65:35 to 72:28, and PEKK2 may comprise terephthalate (T) units and isophthalate (I) units, and a T:l molar ratio strictly greater than 72:28.

[0133] PEKK 2 may have a viscosity index at 25 °C, in a 96% by mass aqueous sulfuric acid solution, according to ISO 307:2019 applied to a poly(aryl ether ketone), lower than that of PEKK 1. In certain embodiments, PEKK 1 may have a viscosity index at 25 °C, in a 96% by mass aqueous sulfuric acid solution, according to ISO 307:2019 applied to a poly(aryl ether ketone). The viscosity index of PEKK 2 may, in particular, be less than or equal to 0.7 dl / g, or even less than or equal to 0.5 dl / g.

[0134] When present in the composition, PAEK represents between 0.1% and 20% by weight, preferably between 1% and 18% by weight, preferably still between 5% and 15% by weight relative to the total weight of PEKK1, TPI and PAEK in the composition.

[0135] According to some embodiments, PAEK may represent between 0.1% and 1% by weight, or between 1% and 2% by weight, or between 2% and 3% by weight, or between 4% and 5% by weight, or between 5% and 10% by weight, or between 10% and 12% by weight, or between 12% and 15% by weight, or between 15% and 18% by weight, or between 18% and 20% by weight, relative to the total weight of PEKK1, TPI and PAEK in the composition.

[0136] According to a preferred embodiment, the PAEK present in the composition according to the invention is PEEK. The PEEK advantageously represents between 0.1% and 15% by weight, preferably between 1% and 12% by weight, and more preferably between 5% and 10% by weight relative to the total weight of PEKK1, TPI, and PEEK in the composition. According to some embodiments, the PEEK may represent between 0.1% and 1% by weight, or between 1% and 5% by weight, or between 5% and 10% by weight, or between 10% and 12% by weight, or between 12% and 15% by weight, relative to the total weight of PEKK1, TPI, and PEEK in the composition.

[0137] Advantageously, the PAEK used in this invention has a molecular weight suitable for the requirements of industrial processes such as injection molding or extrusion.

[0138] Functional fillers or additives

[0139] The compositions according to the invention may include, in addition to the polymers described above, fillers and / or functional additives.

[0140] Among the possible fillers, we can mention in particular silica and alumina, nucleating fillers such as mineral fillers, including talc, carbon fillers, including carbon nanotubes or carbon black, ceramic fillers, including boron nitride (NB), or metal oxides, including ZnO or MgO, and reinforcing fillers, such as glass fibers or carbon fibers.

[0141] Preferably, when the composition includes at least one filler, said at least one filler represents 2% to 30% by weight relative to the total weight of the composition.

[0142] In some embodiments, the composition does not include a charge. In some embodiments, the composition does not include a nucleating charge.

[0143] According to some embodiments, the composition does not include a reinforcing filler.

[0144] The compositions according to the invention may also include one or more functional additives selected from pigments, such as titanium dioxide, zinc sulfide and zinc oxide; UV stabilizers; thermal stabilizers; antioxidants, such as phosphites; acid neutralizers; lubricants; flame retardants; antismoke agents; antistatic agents; anti-adhesion agents; conductive fillers such as carbon black.

[0145] Preferably, when the composition includes at least one functional additive, said at least one functional additive represents 5% or less by weight relative to the total weight of the composition.

[0146] In some embodiments, the composition consists of:

[0147] • PEKK1,

[0148] •TPI,

[0149] •possibly PAEK, and

[0150] • Optionally, at least one functional additive. In some embodiments, the composition consists of:

[0151] • PEKK1,

[0152] •TPI,

[0153] •possibly PAEK,

[0154] •optionally at least one charge, and

[0155] •optionally at least one functional additive.

[0156] Preparation of compositions according to the invention

[0157] The compositions according to the invention can be prepared by any known method allowing a homogeneous mixture of polymers and, where appropriate, fillers and / or functional additives to be obtained.

[0158] Suitable methods include dry blending or melt blending (extrusion). Preferably, the composition is obtained by melt blending.

[0159] The composition can be prepared in powder or granule form, which can then be used to manufacture various objects by common implementation techniques such as laser sintering, powder coating, injection molding, extrusion, compression and extrusion-compression.

[0160] As an example, a method for implementing a composition according to the invention may include the following steps: pre-mixing PEKK and TPI, and where applicable PAEK, at room temperature, to form a composition according to the invention; compounding the composition in a twin-screw extruder, preferably at a temperature between 240 °C and 400 °C and granulating it; injection molding the granules, preferably at an injection temperature between 360 °C and 400 °C.

[0161] The composition can be adapted for use in processes where it is melted and then rapidly cooled, for example, in injection or extrusion processes with air or water cooling. In certain embodiments, such a composition may have a second heating enthalpy measured by DSC with heating ramps at 20°C / min and a cooling ramp at 60°C / min greater than or equal to 15 J / g, preferably greater than or equal to 20 J / g, and preferably greater than or equal to 25 J / g. The enthalpy of fusion is expressed here in joules per gram of total polymer content in the composition.According to another aspect, the invention relates to an article consisting of the composition according to the invention and obtained by a process such as laser sintering, powder coating, injection molding or extrusion, in particular the extrusion of sheets, plates and coating of wires or metal bars.

[0162] In another aspect, the invention relates to the use of the compositions according to the invention and / or articles obtained from such compositions in industrial applications requiring high thermal and mechanical resistance, such as aeronautical components, automotive parts, industrial machinery parts, components for oil and gas extraction, and coatings for electronic and electrical components. In particular, such compositions and / or articles can be used at temperatures, including service temperatures, higher than those generally indicated for PEKK1 alone.

[0163] Examples

[0164] The following examples illustrate the invention without limiting its scope.

[0165] 1 / Raw materials

[0166] - PEKK KEPSTAN®: a poly(etherketone ketone) having a molar ratio in T / l units of 80 / 20, and a viscosity index at 25°C, in a 96% wt. aqueous sulfuric acid solution, of 1.2 dl / g. It is commercially available from Arkema. This polymer is used in the examples as "PEKK1" within the meaning of the invention.

[0167] - Aurum® PL500A and Aurum® PL450C, respectively: thermoplastic polyimides having a glass transition temperature, as measured by DSC in a second heating cycle with heating rates of 10°C / min and a cooling rate of 20°C / min, of 252°C and 253°C, respectively. They are commercially available from Mitsui. These polymers are used in the examples as "TPI" within the meaning of the invention.

[0168] - ULTEM™ 1000: poly(bisphenol A-co-4-nitrophtalic anhydride-co-1,3-phenylenediamine)polyimide (PEI) with a glass transition temperature of 217 °C, according to the corresponding technical data sheet. It is commercially available from Sabic. This polymer is used in the comparative examples because PEI is a polyimide well known to those skilled in the art, generally used to increase the glass transition temperature of PEKK. However, its Tg is too low compared to that of the TPIs used according to the invention. - RADEL® R5000 NT: polyphenylsulfone (PPSU) with a glass transition temperature of 220 °C, as measured by DSC according to the invention, commercially available from Solvay. This polymer is used in comparative examples, because PPSU is a polymer well known to those skilled in the art as a compatible polymer and used in mixtures with poly(aryl ether ketones).

[0169] - PEEK 450G™: poly(ether ketone ketone) consisting of the formula repeating unit (VIII). It is commercially available from Victrex. This polymer is used in the examples as "PAEK" within the meaning of the invention.

[0170] 2 / Preparation of polymer mixtures

[0171] Different polymer compositions were prepared using the polymers and quantities indicated in Table 1. The quantity of each polymer is expressed as a percentage by weight relative to the total weight of the composition. The polymers were first premixed at room temperature and then fed into a Haake II twin-screw extruder operating at a throughput of 2 kg / h with a screw speed of 250 rpm. The extruder temperature profile was controlled from 240°C (feed zone) to 400°C (die zone) to ensure melting or softening of the polymer(s). The extruded and then granulated polymers were injection molded in a Battenfeld BA800 CDC injection molding machine, with the injection temperature maintained between 365°C and 385°C and the mold temperature set at 255°C.

[0172] Compositions C3, C4, C6, C7, and C11 are according to the invention. Compositions C1, C2, C8, C9, C12, C13, and C14 are comparative compositions.

[0173] The compositions implemented are presented in Table 1.

[0174] [Table 1]: Compositions according to the invention and comparative compositions

[0175] (mass proportions)

[0176] 3 / Miscibility and glass transition temperature

[0177] The single glass transition temperature or multiple glass transition temperatures (in cases of total or partial immiscibility) were determined by dynamic mechanical analysis (DMA) performed as indicated in the definitions. The Tg(DMA) values ​​are identified at a maximum of tan 5. The results are presented in Table 2.

[0178] [Table 2]: Glass transition temperature(s) T g (DMA)

[0179] These results show that PEEK and Aurum PL500A TPI are not miscible, even in small proportions (90 / 10), as evidenced by the presence of two distinct Tg values ​​in comparative composition C12. The lowest Tg value at 165°C corresponds to that of PEEK alone (see composition C1). Conversely, PEKK and the TPIs, Aurum PL500A or Aurum PL450C, are miscible up to a proportion of at least 20% by weight of TPI relative to the total weight of TPI and PEKK, as evidenced by the presence of a single Tg value for compositions C11, C13, and C14. The Tg value measured at 187–189°C is higher than that of PEKK alone (179°C, see composition C2). Due to the majority presence of PEKK, the compositions made up of PEKK, PEEK and TPI (C3 to C7) all have a single Tg, the value of which is higher (187°C, 189°C, 193°C and 194°C) than that of PEKK alone (179 °C, see composition C2).

[0180] It should also be noted that the polymers in the PEKK, PEEK, and PEI blend of comparative composition C8 and the polymers in the PEKK, PEEK, and PPSU blend of comparative composition C9 are miscible, as only one Tg was observed. The Tg reached is higher than that of PEKK alone or PEEK alone, but nevertheless lower than those of compositions C6 and C7.

[0181] 4 / Crystallization kinetics

[0182] The prepared compositions were analyzed by DSC to determine their crystallization temperature (Te), carried out as indicated in the definitions, with a first cooling at 20°C / min or at 60°C / min.

[0183] After the first controlled cooling, the sample is heated at 20°C / minute up to 420°C to detect the melting of the crystals formed (2 èmeheating). The area under the endothermic peak recorded during this melting corresponds to the enthalpy of fusion AHf, proportional to the quantity of crystals formed in the polymer mixture.

[0184] The results are presented in Table 3.

[0185] [Table 3]: Crystallization temperatures and enthalpies of fusion The results obtained by DSC show that compositions including PEKK and TPI (comparative examples C13 and C14) crystallize much more slowly than PEKK alone (C2), as evidenced by the significant decrease in crystallization temperature and the significant decrease in enthalpy of fusion (AHf). This notably demonstrates that the addition of a high proportion of TPI significantly reduces the crystallization rate compared to PEKK alone.

[0186] On the other hand, compositions including PEKK, TPI and PEEK (C6 and C7) have a crystallization rate equal to or comparable to that of PEKK alone (C2), and in all cases, a crystallization rate much higher than that of PEKK and TPI mixtures (comparative examples C13 and C14)

[0187] The addition of PEEK therefore improves the crystallization kinetics of the PEKK / TPI mixture, which is advantageous for industrial processes requiring rapid implementation cycles.

[0188] 5 / Thermal aging

[0189] The compositions obtained were used to evaluate their elongation at break after thermal aging on ISO 527-1A type specimens.

[0190] Each specimen was initially air-annealed at 260 °C for 4 hours to ensure that any changes observed during the aging test could not be attributed to structural evolution, such as a change in the degree of crystallinity. Subsequent aging was then carried out in air in an oven at 250 °C for 1003 hours to assess long-term mechanical stability under severe thermal conditions.

[0191] A tensile test was performed after initial annealing and aging using an MTS 810 dynamometer equipped with a mechanical extensometer. The tests were carried out at an ambient temperature of 23 °C, with a tensile speed of 50 mm / min, in accordance with the requirements of ISO 527-1. The results obtained are presented in Table 4.

[0192] [Table 4]: Elongation at break after thermal aging

[0193] Compositions C3 to C7 and C11 are according to the invention. They initially exhibit a higher elongation at break than PEKK alone (Comparison of the nominal (initial) elongation at break of the compositions according to the invention with respect to the nominal (initial) elongation at break of C2). They have comparable aging to PEKK alone since the elongation at break value varies little or not at all before and after aging. This retention of mechanical properties after aging confirms the good thermal stability of the compositions under demanding operating conditions (high temperature and in air).

[0194] Compositions C8 and C9 are comparative compositions. The elongation at break of these compositions decreases considerably after aging. This suggests that these mixtures are more brittle and less suitable for thermally demanding environments.

[0195] The comparative C12 composition shows a low initial elongation at break. Therefore, no aging tests were performed.

[0196] The items listed below are also disclosed here.

[0197] Item 1. Composition comprising:

[0198] • a poly(ether ketone ketone), PEKK1;

[0199] • a thermoplastic polyimide having a glass transition temperature greater than or equal to 230 °C, TPI; and

[0200] • possibly, a poly(aryl ether ketone), PAEK, PAEK being distinct from PEKK1; in which:

[0201] - PEKK1 representing at least 50% by weight, relative to the total weight of PEKK1, TPI and, where applicable, PAEK, of the composition, and

[0202] - PAEK is required to be present when the TPI content is greater than or equal to 20% by weight, and preferably when the TPI content is greater than or equal to 15% by weight, relative to the total weight of PEKK1 and TPI in the composition.

[0203] Item 2. Composition according to item 1, wherein the TPI content is less than or equal to 40% by weight, preferably less than or equal to 35% by weight, preferably still less than or equal to 30% by weight, and preferably still less than or equal to 25% by weight, relative to the total weight of PEKK1 and TPI of the composition.

[0204] Item 3. Composition according to item 1 or item 2, wherein the TPI does not comprise a sulfone group and / or does not comprise an isopropylidene group. Item 4. Composition according to any one of the preceding items, wherein the PEKK1 comprises terephthalate (T) and isophthalate (I) units, the T:I molar ratio ranging from 55:45 to 89:11, and preferably from 72:28 to 85:15.

[0205] Item 5. Composition according to any one of the preceding items, in which the PAEK is selected from:

[0206] • a poly(ether ether ketone), PEEK;

[0207] • a poly(ether ketone), PEK;

[0208] • a poly(ether ketone ether ketone ketone), PEKEKK;

[0209] • a poly(ether ketone ketone) having a T / l ratio higher than that of PEKK1 and / or a lower viscosity index than that of PEKK1, PEKK2; and

[0210] • any mixture of at least two of these polymers.

[0211] Item 6. Composition according to item 5, in which the PAEK is a PEEK.

[0212] Item 7. Composition according to any one of the preceding items, wherein the PAEK content represents from 0.1% to 20% by weight, preferably from 1% to 18% by weight, and more preferably from 5% to 15% by weight, relative to the total weight of PEKK1, TPI and PAEK in the composition.

[0213] Object 8. Composition according to any one of the preceding objects, in which the TPI comprises repeating units of general formula (I):

[0214] [Chem 19] in which

[0215] • X represents a monocyclic or polycyclic tetravalent group, saturated, unsaturated or aromatic, substituted or unsubstituted, comprising from 5 to 50 carbon atoms and possibly one or more heteroatoms; and

[0216] • Ri represents a linear, branched or cyclic divalent radical, substituted or unsubstituted, comprising from 2 to 50 carbon atoms, preferably from 6 to 36 carbon atoms, and possibly comprising one or more heteroatoms.

[0217] Object 9. Composition according to object 8, in which Ri corresponds to the general formula (III):

[0218] [Chem 20] in which Q represents a direct bond or a radical selected from the group consisting of -O-, -C(O)-, -OYO-, alkylenes comprising 1 to 6 carbon atoms, and cycloalkylenes comprising 4 to 8 carbon atoms, where Y represents a group of general formula (II IA) or (HIB):

[0219] [Chem 21] in which

[0220] •Z represents a direct bond or a radical selected from the group consisting of -O-, -C(O)-, alkylenes comprising 1 to 6 carbon atoms, and cycloalkylenes comprising 4 to 8 carbon atoms, and

[0221] •each group Rj, Rk, Ri, Ro and R P is a hydrocarbon group comprising from 1 to 10 carbon atoms and possibly one or more heteroatoms, each index j, k, i, o, and p being an integer from 0 to 4 and representing the number of substitution groups on a ring. Item 10. Composition according to Item 9, in which the TPI comprises repeating units of general formula (IV):

[0222] [Chem 23] Item 11. Composition according to item 9, in which the TPI comprises repeating units of general formula (V):

[0223] [Chem 24]

[0224] Item 12. Composition according to any one of the preceding items, further comprising one or more fillers and / or one or more functional additives.

[0225] Item 13. Article manufactured from the composition according to any one of items 1 to 12.

[0226] Item 14. Method of manufacturing an article according to item 13, comprising at least one step of injection molding or extrusion of the composition according to any of items 1 to 12.

Claims

Demands 1. Composition including: • a poly(ether ketone ketone), PEKK1; • a thermoplastic polyimide having a glass transition temperature greater than or equal to 230 °C, TPI; and • optionally, a poly(aryl ether ketone), PAEK, PAEK being distinct from PEKK1; in which: o PEKK1 represents at least 50% by weight, relative to the total weight of PEKK1, TPI and where applicable PAEK, of the composition, and o PAEK is required to be present when the TPI content is greater than or equal to 15% by weight, relative to the total weight of PEKK1 and TPI of the composition; in which the TPI content is between 5% and 30% by weight, and is less than or equal to 25% by weight, relative to the total weight of PEKK1 and TPI of the composition; in which the PAEK content, when PAEK is present in the composition, represents from 0.1% to 20% by weight, relative to the total weight of PEKK1, TPI and PAEK of the composition.

2. Composition according to claim 1 wherein the TPI does not comprise a sulfone group and / or does not comprise an isopropylidene group.

3. Composition according to any one of the preceding claims, wherein PEKK1 comprises terephthalate (T) and isophthalate (I) units, the T:I molar ratio ranging from 55:45 to 89:11, and preferably from 72:28 to 85:

15.

4. Composition according to any one of the preceding claims, wherein the PAEK is selected from: • a poly(ether ether ketone), PEEK; • a poly(ether ketone), PEK; • a poly(ether ketone ether ketone ketone), PEKEKK; • a poly(ether ketone ketone) having a T / l ratio higher than that of PEKK1 and / or a lower viscosity index than that of PEKK1, PEKK2; and • any mixture of at least two of these polymers.

5. Composition according to claim 4, wherein PAEK is PEEK.

6. Composition according to any one of the preceding claims, wherein the PAEK content represents from 1% to 18% by weight, and preferably from 5% to 15% by weight, relative to the total weight of PEKK1, TPI and PAEK in the composition.

7. Composition according to any one of the preceding claims, wherein the TPI comprises repeating units of general formula (I): in which • X represents a monocyclic or polycyclic tetravalent group, saturated, unsaturated or aromatic, substituted or unsubstituted, comprising from 5 to 50 carbon atoms and possibly one or more heteroatoms; and • Ri represents a linear, branched or cyclic divalent radical, substituted or unsubstituted, comprising from 2 to 50 carbon atoms, preferably from 6 to 36 carbon atoms, and possibly comprising one or more heteroatoms.

8. Composition according to claim 7, wherein Ri corresponds to the general formula (III): [Chem 20] in which Q represents a direct bond or a radical selected from the group consisting of -O-, -C(O)-, -OYO-, alkylenes comprising 1 to 6 carbon atoms, and cycloalkylenes comprising 4 to 8 carbon atoms, where Y represents a group of general formula (II IA) or (II IB): [Chem 21] in which •Z represents a direct bond or a radical selected from the group consisting of -O-, -C(O)-, alkylenes comprising 1 to 6 carbon atoms, and cycloalkylenes comprising 4 to 8 carbon atoms, and •each group Rj, Rk, Ri, Ro and R Pis a hydrocarbon group comprising from 1 to 10 carbon atoms and possibly including one or more heteroatoms, each index j, k, I o and p being an integer from 0 to 4 and representing a number of substitution groups on a ring.

9. Composition according to claim 8, wherein the TPI comprises repeating units of general formula (IV): [Chem 23] 10. Composition according to claim 8, wherein the TPI comprises repeating units of general formula (V): [Chem 24] 11. Composition according to any one of the preceding claims, further comprising one or more fillers and / or one or more functional additives.

12. Article manufactured from the composition according to any one of claims 1 to 11.

13. Method of manufacturing an article according to claim 12, comprising at least one step of injection molding or extrusion of the composition according to any one of claims 1 to 11.

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