Thermoplastic composite materials

Abstract

Disclosed herein are multilayer composite laminates comprising continuous fibers and a polymer matrix comprising a poly(arylene sulfide) (PAS) polymer, a polyetherimide (PEI) polymer, and a polyamide-imide (PAI) polymer.

Description

THERMOPLASTIC COMPOSITE MATERIALS This application claims priority of US provisional application N°63 / 694,024 filed on 12 September 2024 and European patent application N°25150991.5 filed on 09 January 2025, the content of which being entirely incorporated herein by reference for all purposes. In case of any incoherency between this application and one of the priority applications that would affect the clarity of a term or expression, it should be made reference to this application only FIELD OF THE DISCLOSURE

[0001] The present disclosure relates to the field of thermoplastic polymer composites comprising a polymer matrix. More particularly, thermoplastic composite materials that comprise a ternary blend of polymers in the polymer matrix are endowed with improved mechanical properties and reduced propensity to form transverse cracks. BACKGROUND

[0002] Composite materials typically include structural reinforcing fibers embedded in a resin matrix. Composite materials have been employed in a wide variety of applications. For example, continuous fiber composites have been used to form fiber reinforced composite tapes, ribbons, rods, prepregs, laminates, and profiles useful as lightweight structural reinforcements as well as protective casings. Composite materials comprising a thermoplastic polymer matrix are known to offer a number of benefits over thermosetting based materials. For example, thermoplastic prepregs can be more rapidly fabricated into articles. Another advantage is that thermoplastic articles may be recycled.

[0003] In many composite material systems, the polymer matrix may have a coefficient of thermal expansion that may be different from the one of the fibers. This difference may result in the polymer and fibers shrinking or expanding by different amounts when the temperature of the composite structure is cooled. The difference in coefficient of linear thermal expansion of the polymer matrix relative to the fibers may result in thermally- induced stresses in the structure. The thermally-induced stresses may result in undesirable small cracks (including transverse cracks, and / or microcracks) in the polymer matrix, in particular when the part is extracted from the mold. Microcracking may alsooccur during the service life of a composite structure due to continued cycling of temperature or mechanical load from the operating environment.

[0004] Unexpectedly, the Applicant has surprisingly found compositions that include a ternary blend of polymers in the polymer matrix may significantly reduce, if not eliminate the formation of microcracks in composite materials. BRIEF SUMMARY

[0005] In a first aspect, the present disclosure relates to a composite material comprising at least one layer (L). The layer (L) comprises continuous reinforcing fibers and a polymer matrix. The polymer matrix comprises a ternary blend of polymers: a poly(arylene sulfide) (PAS) polymer, a polyetherimide (PEI) polymer, and a polyamide-imide (PAI) polymer. The PEI polymer is present in an amount from 1.0% to 50.0% by weight, and the PAI polymer is present in an amount from 0.1% to 10.0% by weight, both weights being based on the total weight of the polymer matrix.

[0006] Also disclosed herein are articles comprising the composite materials disclosed herein. Such articles can include, but are not limited to, automotive components, gas tanks, battery housings, aerospace components, oil and gas drilling components, a component for Smart Devices, a medical housing or component for medical devices, an Urban Air Mobility device, and an electronic device.

[0007] Surprisingly, the Applicant found that composite materials which include the presently disclosed ternary blend of polymers in the polymer matrix may significantly reduce, if not eliminate the formation of micro-cracks in composite materials. DETAILED DESCRIPTION

[0008] In the present application, any description, even if described in relation to a specific embodiment, is applicable to and interchangeable with other embodiments of the present disclosure, and each embodiment thus defined may be combined with another embodiment, unless otherwise indicated or clearly incompatible.

[0009] Where an element or component is said to be included in and / or selected from a list of recited elements or components, it should be understood that in relatedembodiments explicitly contemplated here, the element or component can also be any one of the individuals recited elements or components, or can also be selected from a group consisting of any two or more of the explicitly listed elements or components; any element or component recited in a list of elements or components may be omitted from such list.

[0010] Any recitation herein of numerical ranges by endpoints includes all numbers subsumed within the recited ranges as well as the endpoints of the range and equivalents.

[0011] The term “comprising” (or equivalents) includes “consisting essentially of,” and also “consisting of.”

[0012] As used herein, the term “consisting essentially of” or “essentially consisting” indicates that the referred to composition contains less than 5 wt%, typically less than 2 wt% or less than 1 wt%, of any other ingredient.

[0013] The use of the singular “a” or “one” herein includes the plural unless specifically stated otherwise.

[0014] It should be understood that the elements, properties, and / or the characteristics of a (co)polymer, product or article, a process, or a use, described in the present specification, may be combined in all possible ways with the other elements, properties and / or characteristics of the (co)polymer, product or article, process or use, explicitly or implicitly, this being done without departing from the scope of the present description.

[0015] Should the disclosure of any patents, patent applications, and publications that are incorporated herein by reference conflict with the description of the present application to the extent that it may render a term unclear, the present description shall take precedence.

[0016] In a first aspect, the present disclosure relates to a composite material comprising at least one layer (L). The layer (L) comprises continuous reinforcing fibers and a polymer matrix. The polymer matrix comprises a ternary blend of polymers: a poly(arylene sulfide) (PAS) polymer, a polyetherimide (PEI) polymer, and a polyamide-imide (PAI) polymer. The PEI polymer is present in an amount from 1.0% to 50.0% by weight, and the PAI polymer is present in an amount from 0.1% to 10.0% by weight, both weights being based on the total weight of the polymer matrix.

[0017] Also disclosed herein are articles comprising the composite materials disclosed herein. Such articles can include, but are not limited to, automotive components, gas tanks, battery housings, aerospace components, oil and gas drilling components, a component for Smart Devices, a medical housing or component for medical devices, an Urban Air Mobility device, and an electronic device.

[0018] Surprisingly, the Applicant found that composite materials which include the presently disclosed ternary blend of polymers in the polymer matrix may significantly reduce, if not eliminate the formation of micro-cracks in composite materials.

[0019] The Composite Material

[0020] The presently disclosed composite materials comprise at least one layer (L), the layer (L) comprising continuous reinforcing fibers and a polymer matrix.

[0021] The composite material can comprise two or more layers (L). The composite material can comprise 2, 4, 5, 6, 7, 8, 10, 12, 15, 20, or 30 layers (L) and up to 50, 80, or 100 layers (L). Generally, composite materials comprising 1 to 80 layers (L) are suitable for most applications.

[0022] The composite material can be a unidirectional composite, also referred to as “tape,” that is a composite wherein the continuous reinforcing fibers in each layer (L) are generally aligned along a single direction, typically along the edge of the composite material. Generally, aligned fibers typically are oriented such that at least 70%, at least 80%, at least 90% or at least 95% of the reinforcing fibers have a direction that is within 30 degrees, within 25 degrees, within 20 degrees, within 15 degrees, or within 10 degrees along the direction of the other fibers.

[0023] Alternatively, the composite material can be a multidirectional composite, in which the continuous reinforcing fibers are arranged at an angle with respect to the others. The continuous reinforcing fibers in the composite material can be arranged as a woven fabric or a layered fabric or any combination of one or more.

[0024] The Layer (L)

[0025] The layer (L) comprises continuous reinforcing fibers and a polymer matrix. In other words, the polymer matrix is impregnated with the continuous reinforcing fibers. As used herein, the expression “continuous reinforcing fiber” refers to a fiber having a length, in the longest dimension, of at least 5 mm.

[0026] The continuous reinforcing fibers can have a length, in the longest dimension, of at least 1 cm, at least 25 cm or at least 50 cm. The length of the continuous reinforcing fibers is dependent on the shape and size of the finished part.

[0027] The continuous reinforcing fibers can be selected from the group consisting of, glass fiber, carbon fibers, aluminum fiber, ceramic fiber, titanium fiber, magnesium fiber, boron carbide fibers, rock wool fiber, steel fiber, aramid fiber and natural fiber (such as cotton, linen and wood). Preferably, the continuous reinforcing fibers are selected from the group consisting of glass fiber, carbon fiber, aramid fiber, and ceramic fiber. The layer (L) can include one or more additional continuous reinforcing fibers, each distinct in composition and as described above.

[0028] Overall, the continuous reinforcing fibers can constitute at least 15 % of the total volume of the layer (L). Typically the continuous reinforcing fibers are at least 20 %, at least 25 %, even at least 30% of the total volume of the layer (L). The continuous reinforcing fibers are typically no more than 80 %, no more than 75 %, even no more than 70% of the total volume of the layer (L). The continuous reinforcing fibers can conveniently represent from 20% to 75%, from 25% to 70%, from 25% to 65%, from 45% to 65%, and from 30% to 60 % of the total volume of the layer (L). The polymer matrix therefore represents the remainder of the volume of the layer (L).

[0029] The Polymer Matrix

[0030] The polymer matrix comprises a ternary blend of polymers. The polymers in the ternary blend are a poly(arylene sulfide) (PAS) polymer, a polyetherimide (PEI) polymer, and a polyamide-imide (PAI) polymer.

[0031] Without wishing to be bound by any particular scientific theory, it has been unexpectedly found that the presently disclosed ternary blend of polymers in the polymer matrix may significantly reduce, if not eliminate the formation of microcracks in composite materials.

[0032] The Poly(Arylene Sulfide) (PAS) Polymer

[0033] The presently disclosed polymer matrix comprises a poly(arylene sulfide) (PAS) polymer. As used herein, a poly(arylene sulfide) polymer refers to any polymer including at least 50 mol% of a recurring unit (RPAS) having the following formula: -[-Ar-S-]-, where Ar is an arylene. The PAS polymer can have at least 60 mol%, at least 70 mol%, at least80 mol%, at least 90 mol%, at least 95 mol%, at least 99 mol% or at least 99.9 mol% of recurring unit (RPAS).

[0034] The recurring unit (RPAS) is represented by a formula selected from the following group of formulae:where R, at each instance, is independently selected from the group consisting of a C1- C12alkyl group, a C7-C24alkylaryl group, a C7-C24aralkyl group, a C6-C24arylene group, and a C6-C18 aryloxy group; T is selected from the group consisting of a bond, –CO-, - SO2-, -O-, -C(CH3)2, phenyl and -CH2-; k, at each instance, is an independently selected integer from 0 to 4; and l, at each instance, is an independently selected integer from 0 to 3.

[0035] Alternatively, or in addition, k and l, at each instance, is zero. Preferably, -Ar- is represented by either Formula (1) or (2), more preferably Formula (1) (recurring unit (RPAS) corresponding to recurring units of polyphenylene sulfide), still more preferably, recurring unit (RPAS) is represented by the following formula:

[0036] The concentration of recurring unit (RPAS) in the PAS polymer is at least 50 mol%, at least 60 mol%, at least 70 mol%, at least 80 mol%, at least 90 mol%, at least 95 mol%, at least 98 mol%, at least 99 mol% or at least 99.9 mol%.

[0037] According to an embodiment of the present invention, the PAS polymer is such that about 100 mol. % of the recurring units are recurring units of Formula 1. According to this embodiment, the PAS polymer consists essentially of recurring units (RPAS) of Formula 1.

[0038] Suitable examples of a PAS polymer as described above include, but are not limited to, poly(2,4-toluene sulfide), poly(4,4'-biphenylene sulfide), poly(phenylene sulfide) including poly(para-phenylene sulfide) (PPS), poly(ortho-phenylene sulfide), poly(meta-phenylene sulfide), poly(xylene sulfide), poly(ethylisopropylphenylene sulfide), poly(tetramethylphenylene sulfide), poly(butylcyclohexylphenylene sulfide), poly(hexyldodecylphenylene sulfide), poly(octadecylphenylene sulfide), poly(phenylphenylene sulfide), poly-(tolylphenylene sulfide), poly(benzylphenylene sulfide) and poly[octyl-4-(3-methylcyclopentyl) phenylene sulfide].

[0039] The PAS polymer can have a weight average molecular weight (“Mw”) of at least 10,000 g / mol, at least 20,000 g / mol, at least 25,000 g / mol, at least 30,000 g / mol, or at least 35,000 g / mol. In some embodiments, the PAS polymer has an Mwof no more than 150,000 g / mol, no more than 100,000 g / mol, no more than 90,000 g / mol, no more than 85,000 g / mol, or no more than 80,000 g / mol. In some embodiments, the PAS polymer has an Mwof from 10,000 g / mol to 150,000 g / mol, from 20,000 g / mol to 100,000 g / mol, from 25,000 g / mol to 90,000 g / mol, from 30,000 g / mol to 85,000 g / mol, or from 35,000 g / mol to 80,000 g / mol. Mw can be measured with gel permeation chromatography (“GPC”) using a 4-chloronapthalene standard.

[0040] The PAS polymer can be semi-crystalline. The person of ordinary skill in the art will recognize that when a polymer is amorphous, it lacks a detectable Tm. Accordingly,when a PAS polymer has a Tm, the person of ordinary skill in the art will recognize that it refers to a semi-crystalline polymer. The PAS polymer can also have a ΔHf of at least 10 J / g, at least 20 J / g, at least, or at least 25 J / g. Alternatively, or in addition, the PAS polymer can have a ΔHf of no more than 90 J / g, no more than 70 J / g or no more than 60 J / g. The PAS polymer can have a ΔHfof from 10 J / g to 90 J / g or from 20 J / g to 70 J / g.

[0041] The PAS polymer can have a melting temperature (“Tm”) of at least 200 ℃, at least 220 ℃, at least 240 ℃, or at least 250 ℃. Alternatively, or in addition, the PAS polymer can have a Tmof no more 350 ℃, no more than 320 ℃, no more than 300 ℃, or no more than 285 ℃. The PAS polymer can have a Tm of from 200 ℃ to 350 ℃, from 220 ℃ to 320 ℃, from 240 ℃ to 300 ℃, or from 250 ℃ to 285 ℃.

[0042] It will be understood that the arylene groups of the PAS polymer can be substituted or unsubstituted.

[0043] Additionally, the PAS polymer can include any isomeric relationship of the sulfide linkages in polymer; e.g., when the arylene group is a phenylene group, the sulfide linkages can be ortho, meta, para, or combinations thereof.

[0044] The PAS polymer of the present disclosure can be obtained by a process known in the art. Reference can notably be made to WO 2015 / 095362 (Chevron Phillips), WO 2015 / 177857 (Solvay) and WO 2016 / 079243 (Solvay).

[0045] The PAS polymer typically represents the balance to 100 wt% in the polymer matrix. The PAS polymer is generally at least 50.0 wt% of the polymer matrix, even at least 55.0 wt%, typically at least 60.0 wt%, or even at least 70.0 wt%.

[0046] The Polyetherimide (PEI) Polymer

[0047] The presently disclosed polymer matrix comprises a polyetherimide (PEI) polymer. The PEI polymer can be an aromatic PEI polymer.

[0048] As used herein, a polyetherimide (PEI) denotes any polymer of which more than 50 mol % of recurring units (RPEI) are selected from the group consisting of units of formulae :and combinations thereof, where : each B, equal to or differentfrom eachother, is independentlyselected from group consisting of –O– and –O–Ar–O–, where Ar is selected from the group consisting of moieties of form :where each R, equal or different from each other, is independently selected from the group consisting of hydrogen, halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine, and quaternary ammonium; each j, k, l, m and n, equal to or different from each other, is independently selected from 0, 1, 2, 3 and 4, preferably 0; and W is selected from the group consisting of alkylenes having 1 to 6 carbon atoms, in particular –C(CH3)2– and – CrH2r– (r being an integer ranging from 1 to 6); perfluoroalkylenes having 1 to 6 carbon atoms, in particular –C(CF3)2– and –CsF2s–(s being an integer ranging from 1 to 6); cycloalkylenes having 4 to 8 carbon atoms; alkylidenes having 1 to 6 carbon atoms; cycloalkylidenes having 4 to 8 carbon atoms; –O– ; –S– ; –C(O)– ; –SO2– ; and –SO–.

[0049] Preferably, B is a group of the formula (B-6), as shown above. More preferably, B is a group of formula:

[0050] E A, equal to or different from each other, is selected from the group, –CtH2t- (t being an integer ranging from 1 to 6), and moieties of formulae :where each R’, equal to or different from each other, is independently selected from the group consisting of hydrogen, halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine, and quaternary ammonium; o, p, q, v, and x, equal to or different from each other, is independently selected from 0, 1, 2, 3 and 4, preferably 0; and Y is selected from the group consisting of alkylenes having 1 to 6 carbon atoms, in particular –C(CH3)2– and – CuH2u– (u being an integer from 1 to 6); perfluoroalkylenes having 1 to 6 carbon atoms, in particular –C(CF3)2– and –CwF2w–(w being an integer from 1 to 6); cycloalkylenes having 4 to 8 carbon atoms; alkylidenes having 1 to 6 carbon atoms; cycloalkylidenes having 4 to 8 carbon atoms; –O– ; –S– ; –C(O)– ; –SO2– ; and –SO–.

[0051] Preferably, A is selected from the group consisting of moieties of formulae (C-0) to (C-2), as shown above. More preferably, A is selected from the group consisting of unsubstituted m phenylene, unsubstituted p phenylene, and a combination thereof.

[0052] In some embodiments, A is a group of formula :(C-7).

[0053] In some embodiments, the recurring units (RPEI) are recurring units selected from(D-0)and combinations thereof.

[0054] In some embodiments, the recurring units (RPEI) are recurring units selected from the group consisting of those of formulae :and combinations thereof.

[0055] Preferably at least 75 mol %, 85 mol %, 95 mol %, and more preferably at least 99 mol % of the recurring units of the PEI polymer are recurring units (RPEI).

[0056] In some embodiments, at least 75 mol %, 85 mol %, 95 mol %, and more preferably at least 99 mol % of the recurring units (RPEI) are units of formula (D-0), their corresponding amic acid forms of formulae (D-1) to (D-6), and combinations thereof.

[0057] In some embodiments, at least 75 mol %, 85 mol %, 95 mol %, and more preferably at least 99 mol % of the recurring units (RPEI) are units of formula (E-0), their corresponding amic acid forms of formulae (E-1) to (E-6), and combinations thereof.

[0058] The PEI polymer may have a weight average molecular weight (Mw) ranging from about 10,000 to about 150,000 g / mole, as measured by gel permeation chromatography using a polystyrene standard.

[0059] The PEI polymer may have a glass transition temperature Tg from 220 ℃ to 250 ℃ (e.g., from 220 ℃ to 240 ℃, from 220 ℃ to 230 ℃, from 230 ℃ to 250 ℃, from 240 ℃ to 250 ℃, or from 230 ℃ to 240 ℃).

[0060] The PEI polymer is present in the polymer matrix in an amount from 1% to 50% by weight, based on the total weight of the polymer matrix (e.g., from 2% to 50%, from 3% to 50%, from 4% to 50%, from 5% to 50%, from 1% to 45%, from 1% to 40%, from 2% to 45%, from 2% to 40%, from 3% to 45%, from 3% to 40%, from 4% to 45%, from 4% to 40%, from 5% to 45%, from 5% to 40%, from 5% to 35%, from 5% to 30%, from 5% to 25%, from 5% to 20%, from 10% to 50%, from 15% to 50%, from 5% to 15%, from 10% to 20%, from 15% to 20%, or from 10% to 15%).

[0061] The Polyamide-Imide (PAI) Polymer

[0062] The presently disclosed polymer matrix comprises a polyamide-imide (PAI) polymer. The PAI polymer of the present disclosure can comprise recurring units having at least 50.0 mol% of the recurring units comprising an aromatic ring and one or more of an amic acid group or an imide group [referred to as recurring units (RPAI) herein]. The PAI polymer can also comprise more than 90.0 mol% of recurring units (RPAI). The polymer solution can comprise one or more than one PAI polymer.

[0063] The acid number (mg of KOH / g polymer) of the PAI polymer) may be 100 or more and even 120 or more. It may be up to the theoretical acid number for a resin that comprises only amic acid units. In certain embodiments, it may be up to 170 mg KOH / g polymer. The acid number may be determined by titration, such as a potentiometric titration method according to ASTM D664. In particular it may be determined by the potentiometric titration method described by ASTM D664, where N-methylpyrrolidone (NMP) is the solvent, and titrants are potassium hydroxide and tributylammonium chloride.

[0064] The recurring units (RPAI) are chosen from the group consisting of:wherein the symbol → in each formula denotes isomerism so that, in any recurring unit within the aromatic polyamic acid structure, the groups to which the arrows point may exist as shown or in an interchanged position; Ar is an aromatic tetravalent group, which may comprise one or more than one aromatic ring, and which are preferably selected from the group consisting of:with X being selected from the group consisting of –O-, -C(O)-, -S-, -SO2-, -CH2-, - C(CF3)2-, -(CF2)n- with n= 1,2,3,4 or 5; R is an aromatic divalent group, which may comprise one or more than one aromatic ring, and which are preferably selected from the group consisting of:, with Y being selected from the group consisting of –O-, -C(O)-, -S-, -SO2-, -CH2-, -

[0065] Alternatively, or in addition, the recurring units (RPAI) are chosen from the group consisting of units (i), (ii), and (iii) as follows:and / or the corresponding imide-group containing recurring unit:wherein the attachment of the two amide groups to the aromatic ring as shown in (i-a) will be understood to represent the 1,3 and the 1,4 polyamide-amic acid configurations;(ii-a), and / or the corresponding imide-group containing recurring unit:(ii-b), wherein the attachment of the two amide groups to the aromatic ring as shown in (ii-a) will be understood to represent the 1,3 and the 1,4 polyamide-amic acid configurations; and(iii-a), and / or the corresponding imide-group containing recurring unit:(iii-b), wherein the attachment of the two amide groups to the aromatic ring as shown in (iii-a) will be understood to represent the 1,3 and the 1,4 polyamide-amic acid configurations.

[0066] The recurring units (RPAI) can be recurring units (i) or a mixture of the recurring units (ii) and (iii).

[0067] The amount of recurring units comprising an amic group can be determined by any suitable technique, such as spectroscopic techniques or titration techniques which are known to those of ordinary skill in the art.

[0068] When recurring units (RPAI) are selected from those of formulae (RPAI-A), (RPAI-B), (RPAI-C), (RPAI-D), (RPAI-E), as detailed above, the molar percentage of recurring units (RPAI) comprising at least one amic acid group may be expressed as follows: where [(RPAI-A) units], [(RPAI-B) units], [(RPAI-C)units], [(RPAI-D) units], and [(RPAI-E) units] denote, respectively molar concentration of the different recurring units (RPAI) as above described.

[0069] When recurring units (RPAI) are selected from those of formulae (RPAI-A), and (RPAI-C), as detailed above, the molar percentage of recurring units (RPAI) comprising at least one amic acid group may be expressed as follows: [(ୖౌ^^-^)^୬୧^^] [(ୖౌ^^-^)^୬୧^^]ା[(ୖౌ^^-େ)^୬୧^^] x100.

[0070] The recurring units (RPAI) can have at least 50.0 mol%, even at least 60.0 mol%, still at least 70.0 mol% of recurring units (RPAI) comprise at least one amic acid group. Alternatively, or in addition, 70.0 to 95.0 mol%, even 75.0 to 90.0 mol% of recurring units (RPAI) comprise at least one amic acid group.

[0071] The PAI polymer can be manufactured by a process which includes the polycondensation reaction between at least an aromatic polycarboxylic acid halide monomer and at least an aromatic diamine.

[0072] The number average molecular weight (Mn) of the PAI polymer can be at least 1000, preferably at least 1500, more preferably at least 2000. The number average molecular weight (Mn) of the PAI polymer can be 20000 or less, preferably 15000 or less. The molecular weight of the PAI polymer (Mw and Mn) may be and is usually determined using gel permeation chromatography (GPC) using a polystyrene standard.

[0073] The PAI polymer is present in the polymer matrix in an amount from 0.1% to 10.0% by weight, based on the total weight of the polymer matrix (e.g., from 0.1% to 9.0%, from 0.1% to 8.0%, from 0.1% to 7.0%, from 0.1% to 6.0%, from 0.1% to 5.0%, from 1% to 5.0%, from 1.0% to 4.0%).

[0074] Additives

[0075] In some embodiments, the polymer matrix can further include optional additives, including but not limited to, antioxidants (e.g. ultraviolet light stabilizers and heat stabilizers), processing aids, nucleating agents, lubricants, flame retardants, smoke- suppressing agents, anti-static agents, anti-blocking agents, colorants, pigments, impact modifiers, and conductivity additives such as carbon black.

[0076] In some embodiments, antioxidants can be particularly desirable additives. Antioxidants can improve the heat and light stability of the polymer matrix in the composite. For example, antioxidants that are heat stabilizers can improve the thermal stability of the composite during manufacturing (or in high heat application settings), for example, by making the polymer processable at higher temperatures while helping to prevent polymer degradation.

[0077] Additionally, the antioxidants that are light stabilizers can further prevent against polymer degradation during use of the composite application settings where it is exposed to light (e.g. external automobile or aircraft parts). Desirable antioxidants include, but are not limited to, copper salts (e.g. CuO and Cu2O), alkaline metal halides (e.g. CuI, KI, and KBr, including combinations of alkaline metal halides such as, but not limited to, CuI / KI), hindered phenols, hindered amine light stabilizers (“HALS”) (e.g. tertiary amine lightstabilizers) and organic or inorganic phosphorous-containing stabilizers (e.g. sodium hypophosphite or manganese hypophosphite).

[0078] In some embodiments, the additive is an impact modifier. In some embodiments, a rubbery low-modulus functionalized polyolefin impact modifier with a glass transition temperature (“Tg”) lower than 25°C is desirable. Specific examples of functionalized impact modifiers are notably terpolymers of ethylene, acrylic ester and glycidyl methacrylate, copolymers of ethylene and butyl ester acrylate; copolymers of ethylene, butyl ester acrylate and glycidyl methacrylate; ethylene-maleic anhydride copolymers; EPR grafted with maleic anhydride; styrene copolymers grafted with maleic anhydride; SEBS copolymers grafted with maleic anhydride; styrene-acrylonitrile copolymers grafted with maleic anhydride; ABS copolymers grafted with maleic anhydride.

[0079] In some embodiments, the additive is a halogen-free flame retardant. In some embodiments, the halogen free flame retardant is an organophosphorous compound selected from the group consisting of phosphinic salts (phosphinates), diphosphinic salts (diphosphinates) and condensation products thereof.

[0080] When present, the total concentration of additives in the polymer matrix is at least 0.1 wt.%, at least 0.2 wt.%, at least 0.5 wt.%, or at least 1.0 wt.%, even at least 2.0 wt.%, relative to the total weight of the polymer matrix. Additionally or alternatively, the total concentration of additives in the polymer matrix is no more than 30.0 wt.%, no more than 20.0 wt.%, no more than 10.0 wt.%, relative to the total weight of the polymer matrix.

[0081] Articles

[0082] The presently disclosed composite materials can be desirably incorporated into articles for use in a wide variety of application settings such as automotive components, gas tanks, battery housings, aerospace components, oil and gas drilling components, a component for Smart Devices, a medical housing or component for medical devices, an Urban Air Mobility device, and an electronic device.

[0083] With respect to automotive applications, the inventive composites can be integrated into automotive components including, but not limited to, pans (e.g. oil pans), panels (e.g. exterior body panels, including but not limited to quarter panels, trunk, hood; and interior body panels, including but not limited to, door panels and dash panels), side- panels, mirrors, bumpers, bars (e.g., torsion bars and sway bars), rods, suspensionscomponents (e.g., suspension rods, leaf springs, suspension arms), turbo charger components (e.g. housings, volutes, compressor wheels and impellers), and housings for battery components. The thermoplastic composites described herein can also be desirably integrated into aerospace components, oil and gas drilling components (e.g. downhole drilling tubes, chemical injection tubes, undersea umbilicals and hydraulic control lines), and mobile electronic device components.

[0084] The embodiments above are intended to be illustrative and not limiting. Additional embodiments are within the inventive concepts. In addition, although the present invention is described with reference to particular embodiments, those skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the invention.

[0085] The present invention will be now described in more detail with reference to the following examples, whose purpose is merely illustrative and not intended to limit the scope of the disclosure.

[0086] Raw Materials

[0087] The poly(phenylene sulfide) (PAS) polymer was RytonⓇM2000 SFP, which is commercially available and was obtained from Solvay Specialty Polymers USA, LLC.

[0088] The polyetherimide (PEI) polymer was UltemⓇ1000, which is commercially available and was obtained from SABIC.

[0089] The polyamide-imide (PAI) polymer was TorlonⓇAI-30, which is commercially available and was obtained from Solvay Specialty Polymers USA, LLC.

[0090] The continuous reinforcing fibers were carbon fibers, commercially available as HexTow®AS4D or Grafil®G34-700 obtained from Hexcel and Mistubishi, respectively.

[0091] Methods of Manufacture

[0092] A slurry impregnation method was used to make the thermoplastic composite. For Examples E1 and E2, blends of PAS particles, PEI particles, and PAI solution were actively mixed in an aqueous colloidal suspension according to the formulations given in Table I. For E1 and E2, unsized carbon fibers commercially available from Mitsubishi under the trade name Grafil®G34-70012K were used. For Example CE3, PAS particles were actively mixed in an aqueous colloidal suspension, and unsized carbon fibers commercially available from Hexcel under the trade name HexTow®AS4D 12K wereused. The individual fiber thickness is about 7 μm. A sufficient number of fibers were used to make a 76 mm-wide unidirectional tape. The dry web of collimated, continuous fibers were passed through the aqueous colloidal suspension of polymers along with a surfactant (Rhodasurf®Bc729, supplied by Syensqo).

[0093] After passing through the aqueous suspension, the web of collimated fibers was passed underneath a series of infrared lamps which evaporated the water and consolidated the polymers on the fibers. The fibers were then passed through a die heated to 340 °C, a heated calendar maintained at 120 °C, and eventually a series of cooling rolls before being coiled onto a cardboard core. The prepreg tapes have a nominal fiber volume fraction of 0.60, which results in a final polymer content of 33 wt% and a fiber areal weight of 150 g / m2.

[0094] Examples

[0095] The following Examples were prepared according to the above. The formulations prepared are given below in Table I. Table I. Example composite materials prepared according to the present disclosure. E1 E2 CE3 PAS Polymer (wt% in the 81% 85% 100% polymer matrix) PEI Polymer (wt% in the 15% 14% polymer matrix) PAI Polymer (wt% in the 4% 1% polymer matrix)

[0096] Laminate Preparation and Characterization

[0097] Composite laminates were prepared on a Rucks KV 275.11 Upstroke Press equipped with 600 mm × 600 mm, a maximum platen temperature of 450 °C, and a maximum press force of 1000 kN. The prepreg tape was cut and welded to proper ply dimensions according to the mold being used to press the laminates. The plies were stacked based on desired thickness and layup of the laminate. The edges of the ply stack were taped with Kapton®to maintain fiber alignment and the dried for 2 h at 80 °C in adesiccant oven. The dried ply stack was sandwiched between Kapton®sheets coated with Zyvax®Composite Shield Release and placed in a steel window frame mold for thermal pressing. The pressing procedure is displayed in Table II. Table II. Pressing procedure of composite materials given in Table I. Temperature (°C) Pressure (kPa) Dwell Time (min) Step 1 340 2413 12-15 Step 2 120 2413 15-18 Step 3 120 0 -

[0098] Samples were cut from the resulting laminates and mechanically tested according to the ASTM standards listed below in Table III. For 0° and 90° flexural tests, a three point loading system for center loading is used to test flexural properties in polymer matrix composites with a standard dimension of 4 mm in thickness and 13 mm in width. A center load is applied to induce three-point bending at a rate of 1 mm / min. For 0° short-beam shear tests, the test sample is placed on a standard fixture with the fibers parallel to the loading direction. A load is applied to induce flex at a rate of 1 mm / min. The results all of which are given in Table III.

[0099] For transverse crack observations, [0 / 90] layup of laminates were cut at a 45° bias and examined using optical microscopy. Specifically, the cut laminates were mounted and set in a two-component epoxy resin (such as Epoxicure 2™ from Buehler). After curing, the puck was progressively abraded and polished using first sandpaper then a diamond slurry on a felt pad. The sandpapers have grits of 280 / P320 to 1200 / P4000, and the series of diamond slurries (Glennel®Diamond Suspension from Electron Microscopy Sciences) have particle sizes sequentially of 3.0 μm, 1.0 μm, and eventually 0.1 μm. The polished samples were then imaged using an optical microscope under magnification levels of 100-300x to look for transverse cracks. The results of which are given in Table III. Table III. Transverse crack and mechanical measurements of composite materials given in Table I.0° flexural 0° flexural 90° flexural 0° Short-beam Transverse strength modulus strength shear strength cracks (MPa) (GPa) (MPa) (MPa) Standards ASTM ASTM ASTM ASTM D2344 D7264 D7264 D7264 E1 1740 ± 80 137 ± 2 91 ± 7 98 ± 1 N CE3 1562 ± 127 144 ± 3 76 ± 4 76 ± 2 Y

[0100] As can be seen, the ternary blend composite material in E1 presents improved 90° flexural strength and 0° short-beam shear strength compared to CE3, which consists of 100% PAS polymer in the matrix.

[0101] Accordingly, the Applicant found that composite materials which include the presently disclosed ternary blend of polymers in the polymer matrix did eliminate the formation of micro-cracks in composite materials.

Claims

CLAIMS 1. A composite material comprising at least one layer (L), the layer (L) comprising continuous reinforcing fibers and a polymer matrix, wherein the polymer matrix comprises: a poly(arylene sulfide) (PAS) polymer; a polyetherimide (PEI) polymer in an amount from 1 to 50% by weight, based on the total weight of the polymer matrix; a polyamide-imide (PAI) polymer in an amount from 0.1% to 10% by weight, based on the total weight of the polymer matrix.

2. The composite material of Claim 1, wherein the PAS polymer is polyphenylene sulfide.

3. The composite material of any of Claim 1 or Claim 2, wherein the PAI polymer comprises recurring units having at least 50.0 mol% of the recurring units comprising (i) an aromatic ring and (ii) one or more of an amic acid group or an imide group [recurring units (RPAI)].

4. The composite material of Claim 3, wherein the recurring units (RPAI) are chosen from the group consisting of:wherein: the symbol → in each formula denotes isomerism so that, in any recurring unit RPAI, the groups to which the arrows point may exist as shown or in an interchanged position; Ar is an aromatic tetravalent group, which may comprise one or more than one aromatic ring, and which is preferably selected from the group consisting of:with X being selected from the group consisting of –O-, -C(O)-, -S-, -SO2-, -CH2-, - C(CF3)2-, -(CF2)n- with n= 1,2,3,4 or 5; and R is an aromatic divalent group, which may comprise one or more than one aromatic ring, and which is preferably selected from the group consisting of: ,with Y being selected from the group consisting of –O-, -C(O)-, -S-, -SO2-, -CH2-, - C(CF3)2-, -(CF2)n- with n= 1,2,3,4 or 5,5. The composite material of any of Claim 3 or Claim 4, wherein the recurring units (RPAI) are chosen from the group consisting of units (i), (ii) and (iii):and / or the corresponding imide-group containing recurring unit:wherein the attachment of the two amide groups to the aromatic ring as shown in (i-a) will be understood to represent the 1,3 and the 1,4 polyamide-amic acid configurations;(ii) (ii-a),and / or the corresponding imide-group containing recurring unit:wherein the attachment of the two amide groups to the aromatic ring as shown in (ii-a) represent the 1,3 and the 1,4 polyamide-amic acid configurations; and(iii-a), and / or the corresponding imide-group containing recurring unit:(iii-b), wherein the attachment of the two amide groups to the aromatic ring as shown in (iii-a) represent the 1,3 and the 1,4 polyamide-amic acid configurations.

6. The composite material of any of Claims 1–5, wherein the PAI polymer has an acid number of 100 or more, and preferably of 120 or more, as measured by mg KOH / g polymer.

7. The composite material of any of Claims 1–6, wherein the PEI polymer has a glass transition temperature Tg from 220 ℃ to 250 ℃.

8. The composite material of any of Claims 1–7, wherein the continuous reinforcing fibers are selected from the group consisting of glass fibers, carbon fibers, aramid fibers, ceramic fibers, and mixture thereof.

9. The composite material of any of Claims 1–8, wherein the volume of the continuous reinforcing fibers is from 45% to 65% with respect to the total volume of the layer (L).

10. The composite material of any of Claims 1–9, wherein the composite is a unidirectional composite.

11. The composite material of any of Claims 1–9, wherein the composite is a multiaxial composite laminate.

12. The composite material of any of Claims 1–11, wherein the composite material has a short beam shear strength of 85 MPa or greater as measured according to ASTM D3244 (2022).

13. The composite material of any of Claims 1–12, wherein the composite material has a 90° flexural strength of 68 MPa or greater as measured according to ASTM D7264 (2021).

14. An article comprising the composite material of any of Claims 1–13.

15. The article of Claim 14, which is selected from the group consisting of an automotive component, a battery housing, an aerospace component, oil and gas drilling components, a component for Smart Devices, a medical housing or component for medical devices, an Urban Air Mobility device and an Electronic Device.

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