Fire-resistant high-flow thermoplastic composition

Abstract

A thermoplastic composition (C) comprising the following ingredients: a poly(biphenyl ether sulfone) (P1), a non-halogenated polyphosphonate (P2), and a white pigment (A1). The composition (C) may further comprise optional ingredients such as a melt stabilizer (A2), a poly(aryl ether ketone) (P3), a poly(para-phenylene sulfide) (P4), a non-halogenated flame retardant synergist (A3), and / or any additives (A4) different than ingredients (P1) to (P4) and (A1) to (A3). A method for improving fire resistance, melt viscosity, and ability to color-match, comprising compounding neat PPSU (P1) with the non-halogenated polyphosphonate (P2), the white pigment (A1), and any optional ingredients. A shaped article, especially an aircraft interior component, comprising or made from the composition (C).

Description

[0001] Fire-resistant high-flow thermoplastic composition CROSS-REFERENCE TO RELATED APPLICATION(S) This application claims priority to U.S. application No.63 / 658002 filed on June 10, 2024 and to European application No.24215863.2 filed on November 27, 2024, the entire content of these applications being incorporated herein by reference for all purposes. TECHNICAL FIELD The present invention relates to a high-flow thermoplastic composition comprising a poly(biphenyl ether sulfone) and a non-halogenated phosphonate flame retardant. Such a composition exhibits an outstanding balance of thermal and rheology properties and is especially well suited for the manufacturing of aircraft interior components. BACKGROUND For several years, the industry, in particular the aircraft industry, has required fire resistant and robust materials for the manufacturing of aircraft interior components such as wall panels, overhead storage lockers, serving trays, seat backs, cabin partitions, and ducts. Materials for use in constructing interior aircraft components must meet stringent flammability safety requirements. Particular requirements include smoke density, flame spread, and heat release values. In the United States, Federal Aviation Regulation (FAR) Part 25.853 sets forth the airworthiness standards for aircraft compartment interiors. The safety standards for aircraft and transportation systems used in the United States include a smoke density test specified in FAR 25.5 Appendix F, Part V Arndt 25-116. Flammability requirements include the “60 second test” specified in FAR 25.853(a) Appendix F, Part I, (a), 1 , (i) and the heat release rate standard (referred to as the OSU 65 / 65 standard) described in FAR F25.4 (FAR Section 25, Appendix F, Part IV), or the French flame retardant tests such as, NF-P-92-504 (flame spread) or NF-P-92-505 (drip test). In another example, the aircraft manufacturer Airbus has smoke density and other safety requirements set forth in ABD0031. In addition, because disinfectants and cleaning products are used on aircraft compartment interiors, it is desirable to provide thermoplastic compositions with improved chemical resistance. Among the key properties of poly(aryl ether sulfone)s are their ability to withstand long periods of exposure to elevated temperatures in air and in water and their processability by conventional thermoplastic techniques. These and other mechanical and physical properties render these resins exceptionally well suited for applications in hostile environments. Among poly(aryl ether sulfone)s polymers, poly(biphenyl ether sulfone)s offer as such a rather attractive combination of properties, especially excellent chemical resistance, high stiffness, high toughness, a rather high fire resistance and a rather high flowability. For these reasons, they appear to be engineering polymers of premium choice for use as the base ingredient of a polymer composition for the manufacture of aircraft interior components. One deficiency which tends to limit their use has been their relatively poor flame resistance and too high melt viscosity in comparison to what is required in large and / or complex parts as are common in the transportation industry. For injection molding of thin wall parts for example, it is still desirable to have a PPSU that has low melt viscosities, so that molding operations can be performed with improved flow and molding performance. Because of its high melt viscosity, PPSU is usually processed at a temperature between 360 and 400°C which is far beyond its glass transition temperature Tg of about 220°C. Therefore, neat poly(biphenyl ether sulfone)s are generally not suitable for the manufacturing of aircraft interior components, since the material requirements by the aircraft industry include both a higher fire resistance and a higher flowability that neat poly(biphenyl ether sulfone)s cannot provide. The state-of-the-art approach to rendering polymers fire resistant is to use additives such as flame retardant additives containing at least one halogen (such as fluorine, bromine or chlorine) or flame retardant additives containing aluminum and / or phosphorus such as metal phosphinate or diphosphinate salts, particularly aluminum diethylphosphinate. Non- brominated and non- chlorinated phosphorous-containing flame retardants may be preferred in certain applications for regulatory reasons, for example organic phosphates and organic compounds containing phosphorous-nitrogen bonds. However, use of such additives with a thermoplastic polymer may have a deleterious effect on the processing characteristics and / or the mechanical performance of articles produced from them. In addition, some of these additives are toxic, and can leach into the environment over time making their use less desirable. In some countries, certain halogenated additives are being phased-out of use because of environmental concerns. It has already been attempted to increase the fire resistance of poly(biphenyl ether sulfone)s. For example, US 5204400 and US 5916958 exemplify various polymer compositions comprising a poly(biphenyl ether sulfone), a polytetrafluoroethylene, and anhydrous zinc borate and / or titanium dioxide ; the compositions of US 5204400 and US 5916958 are in general still not suitable for the manufacturing of aircraft interior components because none of the above listed additives (polytetrafluoroethylene, and anhydrous zinc borate and / or titanium dioxide) helps to reduce substantially the melt viscosity. US 2007 / 0037928A1 describes the use of a fluorocarbon polymer comprising recurring units derived from a perfluorinated mono-olefin and a perfluoroalkylvinylether (such as MFA) for lowering the melt viscosity of poly(biphenyl ether sulfone)s and other sulfone polymers, so that poly(biphenyl ether sulfone) compositions exhibiting a flowability as high as desirable by the aircraft industry can be produced. The choice of MFA or the like makes it further possible to provide poly(biphenyl ether sulfone) compositions exhibiting a fire resistance as high as desirable (as otherwise obtainable e.g. by the incorporation of polytetrafluoroethylene). In a particular embodiment of US’928, as shown in Example 5, the poly(biphenyl ether sulfone) composition may further include a bisphenol A polysulfone, which can also help to reduce the melt viscosity. The compositions of US’928, while realizing a substantial progress when compared to the previously available PPSU compositions, are still not as performing as desirable for the manufacturing of aircraft interior components because the use of MFA or the like results in a substantial loss of toughness, as measured by the penetration impact DYNATUP®test. US 2011 / 060093A1 describes a polymer composition (C) containing (i) a poly(biphenyl ether sulfone) “PPSU” and optionally a bisphenol A polysulfone “PSU” and (ii) a combination of a MFA and a PTFE, and further discloses a shaped article comprising the polymer composition (C), which is said to be especially suitable for aircraft interior components. In a particular embodiment of US’093, as shown in example E1, the poly(biphenyl ether sulfone) composition had a viscosity ^3513 at high shear rate (D=3513 s-1) of 185 Pa∙s, which is above the desirable level of ^3513 of 175 Pa∙s or less especially for certain applications when extremely thin parts have to be molded. Similarly to US’928, the addition of PSU to the PPSU compositions helped to reduce the melt viscosity as shown in examples E2 and E3. However in practice there can be processing issues when molding such PPSU compositions without PSU, such as those exemplified by Example E1 in US 2011 / 060093. The PPSU-based compositions in US 5204400, US 5916958, US 2007 / 0037928 and US 2011 / 060093 however all contained at least one fluorinated polymer, PTFE and / or MFA. The addition of halogen containing flame retarding agents to polysulfones, although improving their flammability rating (UL94, V-0), presents a drawback in that the high temperatures required in the thermoplastic processing of polysulfones may cause a decomposition of the additives and consequential poor properties of the molded part. Moreover, some flame retarding additives tend to increase the melt viscosity rendering the resulting compositions more difficult to mold and increasing the risk of molding defects in the resulting molded articles. Replacing these fluorinated polymers with non-halogenated substitutes in these PPSU-based compositions though is not very straightforward, because there is a high risk that the highly desired properties of high fire resistance and / or high flowability may be negatively impacted. For example, the non-halogenated substitutes would need to sustain the molding processing conditions, meaning that they should not be thermally and / or chemically degraded during the preparation of the PPSU-based composition or during the making of an article from such a composition. As such, the removal of these fluorinated materials such as PTFE which is generally used as anti-dripping agent and / or MFA which is generally used as flow enhancer from these PPSU-based compositions present a significant challenge for reformulation. SUMMARY The present invention aims to address several challenges, especially associated with molded interior aircraft articles, by providing a fire-resistant high-flow thermoplastic composition which exhibits surprisingly a unique combination of high fire resistance and high flowability (as high as desirable to make it possible to mold aircraft interior components), while still providing suitable mechanical properties. Of course, these improvements cannot be at the detriment of good chemical resistance from PPSU-based compositions. In this invention, a non-halogenated polyphosphonate is used as efficient flame retardant and furthermore as flowability enhancer to address the demand for PPSU-based formulations that are more environmentally friendly and thus that utilize halogen-free flame retardant, but also have a reduced melt viscosity to improve flow during molding and to reduce injection molding defects (e.g., splaying) when these PPSU-based formulations are molded to form articles. Of course, these improvements cannot be at the detriment of mechanical properties and chemical resistance. The various aspects of the present invention are set out in the appended set of claims. A first aspect of the invention relates to a non-halogenated fire-resistant high-flow thermoplastic composition (C) [ hereinafter “composition (C)” ] defined in any one of claims 1-11. The composition (C) is particularly suitable as thermoplastic molding compositions. In particular, the composition (C) according to the invention comprises the following ingredients: - at least one poly(biphenyl ether sulfone) (P1), - at least one non-halogenated polyphosphonate (P2), and - at least one white pigment (A1). The composition (C) according to the invention may further comprise at least one of the following optional ingredients: - at least one poly(aryl ether ketone) (P3) and / or at least one poly(para- phenylene sulfide) (P4), and / or - at least one melt stabilizer (A2), and / or - at least one non-halogenated flame retardant synergist (A3), and / or - one or more other additives (A4) which is / are different than ingredients (P1) to (P4) and (A1) to (A3). The at least one white pigment (A1) and optional ingredients used in the composition (C) are preferably non-halogenated. In the present invention, halogenated flame retardants are preferably not present in the composition (C). In the present invention, phosphinate and phosphate salt flame retardants are preferably not present in the composition (C). A second aspect of the invention relates to a method for manufacturing such a composition (C) defined in claim 12. A third aspect of the invention relates to a shaped article defined in claim 13, which comprises or is made from the composition (C). In particular, the shaped article may be an interior aircraft component. A fourth aspect of the invention relates to a method defined in claim 14 for improving the properties related to fire resistance, melt flowability and ability to color-match of a neat poly(biphenyl ether sulfone) so as to form the composition (C). A sixth aspect of the invention is the use defined in claim 15 of such a composition (C) to make a shaped article, particularly an interior aircraft component. A further aspect of the invention relates to an aircraft comprising such a shaped article. More precisions and details about various embodiments, advantages, and features of the invention will be more readily understood and appreciated by reference to the detailed description and examples. DETAILED DESCRIPTION Definitions In the present descriptive specification, some terms are intended to have the following meanings. In the present disclosure, the term “recurring unit” designates the smallest unit of a polymer which is repeating in the polymeric chain. The term “recurring unit” is synonymous to the terms “repeating unit” and “structural unit”. As used herein, the term “homopolymer” encompasses a polymer which only has one type of recurring unit. As used herein, the term “copolymer” encompasses a polymer which may have two or more different types of recurring units. As used herein, the term ‘ppm” means parts per million and unless otherwise stated, it is on weight basis. For example, a content of 500 ppm X is equivalent to 500 micrograms of X per gram of composition (C). As used herein, the term “non-halogenated” when used in relation to an ingredient such as a the flame retardant (P2), the white pigment (A1), optional polymer(s), optional additive(s), etc. indicates that ingredient contains less than 900 ppm of each halogen (Cl, Br, F, I), said ppm being based on weight, or less than 1500 ppm when two or more halogens are present. For chlorine and bromine, the ‘halogen-free’ standard called IEC 61249-2-21 from the International Electrochemical Commission (IEC) is applicable in the present definition, as it defines halogen-free as the following: Cl < 900 ppm, or Br < 900 ppm, or the sum of both Cl + Br is < 1500 ppm. The halogen content may be measured by IC-combustion, by a halogen analyzer or by XRF. It should be understood that a poly(biphenyl ether sulfone) as PPSU (P1) has connected recurring units that form at least one main polymeric chain and also so-called “end groups” terminating the polymeric chain(s). For the purpose of the present invention, the poly(biphenyl ether sulfone) preferably does not contain any halogen in the recurring units, meaning no halogen atom is present in the main polymeric chain(s) and in any of its pendant groups branching off the main polymeric chain(s). However, some of its end groups typically comprise a halogen atom such as chlorine and / or fluorine, preferably chlorine, which are derived from halogenated monomers such as dichlorodiphenylsulfone and / or difluorodiphenylsulfone used during its synthesis. As such, the halogen content in the poly(biphenyl ether sulfone) as PPSU (P1) may be at most 5000 ppm F and / or Cl. Most commercial grades of poly(biphenyl ether sulfone)s may typically have a chlorine content of from 3000 to 4500 ppm, while others are halogen-free and may have a chlorine content of 300 ppm to 900 ppm (by weight). In the present specification, the choice of an element from a group of elements (such as a Markush group) also explicitly describes: - the choice of two or the choice of several elements from the group, - the choice of an element from a subgroup of elements consisting of the group of elements from which one or more elements have been removed. In the passages of the present specification which will follow, any description, even though described in relation to a specific embodiment, is applicable to and interchangeable with other embodiments of the present disclosure. Each embodiment thus defined may be combined with another embodiment, unless otherwise indicated or clearly incompatible. In addition, it should be understood that the elements and / or the characteristics of a polymer, a reaction medium, a composition, a solution, a product or article, a process or a use, described in the present specification, may be combined in all possible ways with the other elements and / or characteristics of the polymer, reaction medium, composition, solution, product or article, process or use, explicitly or implicitly, this being done without departing from the scope of the present description. In the present application, 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 related embodiments explicitly contemplated here, the element or component can also be any one of the individual 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. Further, it should be understood that elements, embodiments, and / or features of processes or methods described herein can be combined in a variety of ways without departing from the scope and disclosure of the present teaching, whether explicit or implicit herein. In the present specification, the description of a range of values for a variable, defined by a bottom limit, or by a top limit, or by a bottom limit and a top limit, also comprises the embodiments where the variable is chosen, respectively, within the range of values: excluding the bottom limit, or excluding the top limit, or excluding the bottom limit and the top limit. 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. The term "comprising" (or “comprise”) includes "consisting essentially of" (or “consist essentially of”) and also "consisting of" (or “consist of”). The term “consisting essentially of” in relation to a polymer, composition, product, polymer, solution, process, method, etc. is intended to mean that any additional element or feature which may not be explicitly described herein and which does not materially affect the basic and novel characteristics of such a polymer, composition, product, polymer, solution, process, method, etc. can be included in such an embodiment. For example, when a polymer, composition, compound, product, polymer, or solution “consists essentially of” required elements, it is generally understood that any additional element may be present in not more than 1 wt.% based on the total weight of the polymer, composition, compound, product, polymer, solution, etc. or not more than 1 mol% based on the total number of moles of the polymer, composition, compound, product, polymer or solution. In the particular context of polymer (such as P1, P2, P3, P4, etc.), the expression ‘consisting essentially of’ is used for defining constituents of the polymer to take into account end chains, defects, irregularities and monomer rearrangements which might be comprised in said polymer in minor amounts, without this modifying essential properties of the polymer. The use of the singular ‘a’ or ‘one’ herein means “at least one” and includes the plural unless specifically stated otherwise. The disclosure of all patent applications, and publications cited herein are hereby incorporated by reference, to the extent that they provide exemplary, procedural or other details supplementary to those set forth herein. Should the disclosure of any patents, patent applications, and publications which 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. COMPOSITION (C) The particular advantages of the thermoplastic composition (C) according to the invention are as follows: - fire resistance meeting the requirements of FAR 25.853 (d), Appendix F, Part IV equivalent to FAA Fire Test Handbook, Chapter 5; Boeing BSS 7322; and Douglas DMS 2277 and being compliant with 14 CFR 25.853(d); - suitable melt flowability, which is the same or better than current halogenated PPSU-based products, to permit the composition (C) to be molded into an article with less defects (such as splaying); and - ability to color-match to permit a shaped article comprising, or made from, the composition (C) to be colored according to the end user’s specification. In addition, the thermoplastic composition (C) according to the invention has suitable mechanical properties for its intended end use in aircraft interior components. In addition, the thermoplastic composition (C) according to the invention has suitable chemical resistance to be used in aircraft interior components which may be subjected to possible staining agents. Properties of Composition (C) The thermoplastic composition (C) according to the invention is heat resistant, having an average 2 minute OSU Heat Release Total value of < 65 kW min / m2and an average OSU Peak Heat Release Value of < 65 kW / m2when tested in accordance to the requirements of FAR 25.853 (d), Appendix F, Part IV. The Heat Release Rate (OSU) test is used by the aerospace / aviation industry to determine the heat release rate of cabin compartment materials when exposed to radiant heat. This OSU test is most commonly used to show compliance with 14 CFR 25.853(d). Test methods equivalent to 14 CFR 25, Appendix F, Part IV are FAA Fire Test Handbook, Chapter 5; Boeing BSS 7322; and Douglas DMS 2277. Items in transport category aircraft require the Heat Release test when these items are located in a compartment occupied by the passengers. These items typically include: ^ ceiling panels and wall panels ^ partitions ^ galley structures ^ cabinet walls ^ stowage compartments The thermoplastic composition (C) according to the invention further has at least one of the following properties: - a tensile yield strength measured using ASTM D-638 (2022) of at least 55 MPa (8,000 psi), with values of at least 69 MPa (10 kpsi) being preferred; and / or - a yield elongation measured using ASTM D-638 (2022) of at least about 5 %; and / or - a tensile modulus measured using ASTM D-638 (2022) of at least 1720 MPa (250 kpsi); and / or - a flexural strength measured using ASTM D790 (2017) of at least 82.5 MPa (12 kpsi), with values of at least 93 MPa (13.5 kpsi) being preferred; and / or - a flexural modulus measured using ASTM D790 (2017) of at least 2068 MPa (300 kpsi); and / or - a notched Izod impact (++) measured using ASTM D256 (2023) of at least 53.4 J / m (1.0 ft•lb / in); and / or - a melt viscosity ^100at shear rate=100 s-1measured at 340oC (ASTM D3835, 2016) of at most 1300 Pa.s; and / or - an onset glass transition point Tg(measured by DCS, 2ndheat) which is less than the onset glass transition point Tg(PPSU)of neat PPSU,which is preferably at least 10oC less than Tg(PPSU), which is more preferably at least 15oC less than Tg(PPSU), and which is still more preferably at least 20oC less than Tg(PPSU). A typical Tg(PPSU)value is 216-220oC. Formulation of Composition (C) The non-halogenated fire-resistant high-flow thermoplastic composition (C) [hereinafter “composition (C)”] comprises: - at least one poly(biphenyl ether sulfone) (P1) [hereinafter “PPSU (P1)”], - at least one non-halogenated polyphosphonate (P2) [hereinafter “nhPPP (P2)”]; and - at least one white pigment (A1). The composition (C) may particularly comprise the following ingredients: - between 60 wt.% and 94 wt.% of at least one PPSU (P1), - from 5 wt.% to 20 wt.% of at least one nhPPP (P2), and - from 1 to 10 wt.% of at least one white pigment (A1), wherein the wt.% of each ingredient is based on the total weight of the composition (C), and wherein the combined weights from the ingredients (P1), (P2), (A1) is less than or equal to 100 wt.% based on the total weight of the composition (C). The composition (C) may further comprise at least one melt stabilizer (A2). The composition (C) may even more particularly comprise the following ingredients: - between 60 wt.% and 93.95 wt. % of at least one PPSU (P1), - from 5 wt.% to 20 wt.% of at least one nhPPP (P2), - from 1 to 10 wt.% of at least one white pigment (A1), and - from 0.05 to 1 wt.% of at least one melt stabilizer (A2), wherein the wt.% of each ingredient is based on the total weight of the composition (C), and wherein the combined weights from the ingredients (P1), (P2), (A1), (A2) is less than or equal to 100 wt.% based on the total weight of the composition (C). Yet even more particularly, the composition (C) according to the invention may comprise the following ingredients: - between 60 wt.% and 90 wt.% of at least one PPSU (P1), - from 8 wt.% to 16 wt.% of a nhPPP (P2), - from 1 to 8 wt.% of a white pigment (A1), - from 0.05 to 1 wt.% of at least one melt stabilizer (A2), - from 0 wt.% to 30 wt.%, of at least one poly(aryl ether ketone) (P3) [hereinafter “PAEK (P3)”], and / or at least one poly(para-phenylene sulfide) (P4) [hereinafter “PPS (P4)”], - from 0 wt.% to 20 wt.% of at least one non-halogenated flame retardant synergist (A3) [hereinafter “FR synergist (A3)”], and - from 0 wt.% to 5 wt.% of other additives (A4), wherein the wt.% of each ingredient is based on the total weight of the composition (C), and wherein the combined weights from the ingredients (P1), (P2), (A1), (A2), (P3), (P4), (A3), (A4) is less than or equal to 100 wt.% based on the total weight of the composition (C). The composition (C) according to the invention may have a phosphorus content of from 0.1 wt.% to 5.0 wt.%, or from 0.2 wt.% to 4.0 wt.%, or from 0.5 wt.% to 3.0 wt.%, or from 0.8 wt.% to 2.5 wt.%, based on the total weight of the composition (C). Phosphorus content may be measured through inductively coupled plasma (ICP) or x-ray fluorescence (XRF) spectroscopy with appropriate calibration. It is also possible to estimate the maximum P content in the composition (C) by calculating the weight percentage (wt.%) of the total amount of P originating from the ingredients used in the composition (C), principally from the polyphosphonate flame retardant (P2), divided by the total weight of the composition (C). The composition (C) according to the invention does not contain any per(halo)fluoropolymer, or, when the composition (C) contains a per(halo)fluoropolymer, its content in per(halo)fluoropolymers is >0 and less than 0.5 wt.%, or preferably less than 0.3 wt.%, or more preferably less than 0.1 wt.%, based on the total weight of the composition (C). As used herein, a per(halo)fluoropolymer material is intended to denote one or more per(halo)fluoropolymers, i.e. one or more polyaddition polymers of which at least 98.0 wt.% of the recurring units are derived from at least one per(halo)fluoromonomer or perfluoromonomer which is free of halogen other than fluorine. In particular, the composition (C) does not contain any fluorocarbon polymer comprising recurring units derived from at least one perfluorinated monoolefin and at least one perfluoroalkylvinylether (such as MFA), examples of which are described in US 2007 / 0037928A1. PTFE is commonly known as an anti-drip agent in molding compositions. Preferably though, the composition (C) according to the invention does not contain any polytetrafluoroethylene (PTFE), or, when the composition (C) contains PTFE, its PTFE content is >0 and less than 0.5 wt.%, or less than 0.3 wt.%, or preferably less than 0.1 wt.%, based on the total weight of the composition (C). In particular, the composition (C) does not contain any PTFE which are described in US 5204400, US 5916958, US 2007 / 0037928A1 and US 2011 / 060093A1. The composition (C) according to the invention does not contain any halogenated organic flame retardant, or when the composition (C) contains an halogenated organic flame retardant, its content in halogenated organic flame retardant(s) is >0 and less than 0.5 wt.%, or preferably less than 0.3 wt.%, or more preferably less than 0.1 wt.%, based on the total weight of the composition (C). Examples of halogenated organic flame retardants may be halogenated bisphenols of which the following are representative: 2,2- bis-(3,5- dichlorophenyl)-propane; bis-(2-chlorophenyl)-methane; bis(2,6- dibromophenyl)- methane; l,l-bis-(4-iodophenyl)-ethane; l,2-bis-(2,6- dichlorophenyl)-ethane; l,l-bis-(2- chloro-4-iodophenyl)ethane; l,l-bis-(2-chloro- 4-methylphenyl)-ethane; 1 , 1 -bis-(3,5- dichlorophenyl)-ethane; 2,2-bis-(3- phenyl-4-bromophenyl)-ethane; 2,6-bis-(4,6- dichloronaphthyl)-propane; and 2,2-bis-(3,5-dichloro-4-hydroxyphenyl)-propane 2,2 bis-(3- bromo-4- hydroxyphenyl)-propane. Other examples of halogenated organic flame retardant materials include 1,3-dichlorobenzene, 1 ,4-dibromobenzene, l,3-dichloro-4- hydroxybenzene, and biphenyls such as 2,2'- dichlorobiphenyl, polybrominated 1 ,4-diphenoxy benzene, 2,4'-dibromobiphenyl, and 2,4'- dichlorobiphenyl as well as decabromo diphenyl oxide, as well as oligomeric and polymeric halogenated aromatic compounds, such as a copolycarbonate of bisphenol A and tetrabromobisphenol A and a carbonate precursor, e.g., phosgene. Yet another example of halogenated organic flame retardant includes linear or branched brominated polycarbonate polymers or oligomers, any mixtures thereof, and any copolymers thereof. The composition (C) according to the invention does not contain any metal borate such as zinc borate, or, when the composition (C) contains metal borate salt such as zinc borate, its content in metal borate (e.g., ZnB) is >0 and at most 1 wt.%, or at most 0.8 wt.%, or at most 0.6 wt.%, or at most 0.4 wt.%, or preferably at most 0.2 wt.%, based on the total weight of the composition (C). The composition (C) does not contain any flame retardant additives containing aluminum and / or phosphorous, such as phosphinate salts, particularly aluminum phosphinate salts. Or, when the composition (C) contains one or more flame retardant additives containing aluminum and / or phosphorus such as metal phosphonate salts, and particularly aluminum metal phosphinate salts, their combined content is >0 and less than 3 wt.%, or less than 2.5 wt.%, or less than 2 wt.%, or less than 1.5 wt.%, or preferably less than 1 wt.%, or more preferably less than 0.5 wt.%, based on the total weight of the composition (C). The terms "phosphinic salt" or "phosphinate" as used herein include salts of phosphinic and diphosphinic acids and polymers thereof. A "phosphinate" refers to any inorganic metal phosphinate salt, organic phosphinate salt, phosphinate esters or salts of phosphinic acids. Exemplary phosphinic acids as a constituent of the phosphinic salts include dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid, methyl-n-propylpbosphinic acid, methanedi(methylphosphinic acid), benzene-1,4-(dimethylphosphinic acid), methylphenylphosphinic acid and diphenylphosphinic acid. A commercial example of such a phosphinate flame retardant is Exolit® OP 1230-aluminum diethylphosphinate from Clariant. Because the PPSU (P1) requires high processing temperature (such as ≥ 340oC) during compounding with the other ingredients in order to make the composition (C), the flame retardant additives containing aluminum and / or phosphorus, such as phosphinate or phosphate salts, are not sufficiently thermally stable to sustain such a high processing temperature. As a result, their likely degradation, even if partial, during compounding and / or extrusion renders them unsuitable for this type of PPSU-based compositions. Even if at least a portion of the flame retardant additive containing aluminum and / or phosphorus would survive the high processing temperature conditions, it is likely that its efficacy in imparting fire resistance to the PPSU-based composition would be significantly reduced, and / or that its degradation products could even degrade the properties of the PPSU-based composition. The poly(biphenyl ether sulfone) (P1) As previously mentioned, the polymer composition (C) contains a poly(biphenyl ether sulfone) (P1). The poly(biphenyl ether sulfone) is generally abbreviated as “PPSU” in the present text. As used herein, a PPSU denotes any polymer of which more than 50 mol % of its recurring units, based on the total number of moles of recurring units in the PPSU, are recurring units (RPPSU) of formula (K): , Preferably, at least 60 mol %, at least 70 mol %, at least 80 mol %, at least 90 mol %, at least 95 mol %, at least 99 mol %, or most preferably all, of the recurring units in the PPSU are recurring units (RPPSU) of formula (K), said mol % being based on the total number of moles of recurring units in the PPSU. PPSU can be prepared by known methods and is notably available as RADEL®PPSU from Solvay Specialty Polymers USA, LLC (Syensqo group). The poly(biphenyl ether sulfone) (P1) may be used in pellet form and / or powder form. The poly(biphenyl ether sulfone) (P1) has a melt flow rate (“MFR”) of from 12 to 40 g / 10 min measured with 5.0 kg load at a temperature of 365oC according to ASTM D1238 (2023). Suitable but non-limiting examples of poly(biphenyl ether sulfone) (P1) are Radel® R-5500NT having a melt flow rate of 12-17 g / 10 min (5.0 kg load ; 365oC); Radel® R-5600NT having a melt flow rate of 30-40 g / 10 min (5.0 kg load ; 365oC); Radel® R-5800NT having a melt flow rate of 20-28 g / 10 min (5.0 kg load ; 365oC); Radel® R-5900NT having a melt flow rate of 26-36 g / 10 min (5.0 kg load ; 365oC). The MFR for these Radel® PPSU products are measured with 5.0 kg load at a temperature of 365oC according to ASTM D1238 (2023). When the composition (C) is intended for injection molding, the PPSU (P1) has a MFR of at least 25 g / 10 min, at least 27 g / 10 min, at least 30 g / 10 min, or at least 34 g / 10 min, said MFR being measured with 5 kg load at a temperature of 365oC (ASTM D1238, 2023). Particularly suitable PPSU products to be used as PPSU (P1) in the composition (C) for injection molding are Radel® R-5600NT, Radel® R-5800NT and / or Radel® R-5900NT. When the composition (C) is intended for extrusion, the PPSU (P1) has a melt flow rate (MFR) of less than 25 g / 10 min, at most 22 g / min, or at most 20 g / 10 min, with 5 kg load at a temperature of 365oC (ASTM D1238, 2023). Particularly suitable PPSU products for extrusion are Radel® R-5100NT and / or Radel® R-5200NT. The content of the PPSU (P1) in the composition (C) is at least 61 wt.%, or at least 63 wt.%, or at least 65 wt.%, or at least 68 wt.%, or at least 71 wt.%, or at least 73 wt.%, or at least 75 wt.%, based on the total weight of the composition (C). When high flowability is desirable for the composition (C), the content of the PPSU (P1), based on the total weight of the composition (C), is preferably below 95 wt.%, or at most 94 wt.%, or at most 93.95 wt.%, or at most 93 wt.%, or at most 91 wt.%, or at most 90 wt.%, or at most 88 wt.%, or at most 86 wt.%, or at most 84 wt.%, or at most 82 wt.%, or at most 80 wt.%, based on the total weight of the composition (C). Non-halogenated polyphosphonate (P2) As previously mentioned, the polymer composition (C) contains a non- halogenated polyphosphonate (P2). The non-halogenated polyphosphonate is generally abbreviated as “nhPPP” in the present text. The nhPPP (P2) may be a polymer having recurring units (RnhPPP) of formula (I): , C2-20alkene, C2-20alkyne, C5- 20 20from 2 to about 200, or from 2 to about 100, or from 2 to about 50. The nhPPP (P2) comprises, based on the total number of moles of recurring units in the nhPPP (P2), at least 80 mol %, or at least 85 mol %, or at least 90 mol %, or at least 95 mol %, or at least 97 mol %, or at least 99 mol %, or essentially 100 mol %, of recurring units (RnhPPP) of Formula (I). In the Formula (I), the linking group Ar and the group R do not contain any halogen atom. The —O—Ar—O— in the formula (I) is derived from an aromatic diol which is not halogenated, meaning that it does not contain any halogen atom. The aromatic diol is preferably selected from the group consisting of resorcinols, hydroquinones, bisphenols, and combinations thereof. A single aromatic diol may be used, or various combinations of such aromatic diols may be incorporated into the nhPPP (P2). Some illustrative examples of aromatic diols include the following: bisphenol compounds such as 4, 4'-dihydroxy biphenyl, l,4- dihydroxynaphthalene, l,5-dihydroxynaphthalene, l,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7- dihydroxynaphthalene, bis(4- hydroxyphenyl)methane, bis(4-hydroxyphenyl)phenylmethane, bis(4- hydroxyphenyl)diphenylmethane, bis(4-hydroxy-3,5-dimethylphenyl)methane, bis(4- hydroxy-3,5-dichlorophenyl)methane, bis(4-hydroxy-3,5- dibromophenyl)methane, bis(4- hydroxy-3-methylphenyl)methane, bis(4- hydroxy-3-chlorophenyl)methane, bis(4- hy droxyphenyl)- 1 -naphthylmethane, 1 ,2-bis(4-hydroxyphenyl)ethane, 1 , 1 -bis(4- hydroxyphenyl)-l-phenylethane, 2,2-bis(4-hydroxyphenyl)propane (“bisphenol A” or “BPA”), 2-(4- hydroxyphenyl)-2-(3-hydroxyphenyl)propane, l,l-bis(4- hy droxyphenyl)cy clopentane, 1 , 1 -bis(4-hy droxyphenyl)cy clohexane, 1 , 1 -bis(4-hydroxy-3- methylphenyl)cyclohexane, l,l-bis-(4-hydroxyphenyl)-3, 3, 5-trimethylcy clohexane, 1,1- bis(4-hydroxyphenyl)isobutene, l,l-bis(4- hydroxyphenyl)cyclododecane, trans-2,3-bis(4- hydroxyphenyl)-2-butene, 2,2- bis(4-hydroxyphenyl)adamantane, alpha, alpha'-bis(4- hydroxyphenyl)toluene, bis(4-hydroxyphenyl)acetonitrile, 2,2-bis(3-methyl-4- hydroxyphenyl)propane, 2,2-bis(3-ethyl-4-hydroxyphenyl)propane, 2,2-bis(3-n-propyl-4- hydroxyphenyl)propane, 2,2-bis(3-isopropyl-4-hydroxyphenyl)propane, 2,2- bis(3-sec-butyl- 4-hydroxyphenyl)propane, 2,2-bis(3-t-butyl-4- hydroxyphenyl)propane, 2,2-bis(3-cyclohexyl- 4-hydroxyphenyl)propane, 2,2- bis(3-allyl-4-hydroxyphenyl)propane, 2,2-bis(3-methoxy-4- hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2- bis(4-hydroxy- 3-chlorophenyl)propane, 2,2-bis(4-hydroxy-3,5- dichlorophenyl)propane, 4,4'- dihydroxybenzophenone, bis(4-hydroxy-3,5- dimethylphenyl)ketone, bis(4-hydroxy-3,5- dichlorophenyl)ketone, 3,3-bis(4- hydroxyphenyl)-2-butanone, l,6-bis(4-hy droxyphenyl)- 1,6- hexanedione, ethylene glycol bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)ether, bis(4- hy droxyphenyl) sulfide, bis(4-hydroxyphenyl)sulfoxide, bis(4- hydroxyphenyl)sulfone, 9,9- bis(4-hydroxyphenyl)fluorene, 2,7- dihydroxypyrene, 6,6'-dihydroxy-3,3,3',3'- tetramethylspiro(bis)indane (“spirobiindane bisphenol”), phenolphthalein and phenolphthalein derivatives, 3,3-bis(4-hydroxyphenyl)phthalimide, 2, 6-dihydroxy dibenzo-p- dioxin, 2,6- dihydroxythianthrene, 2,7-dihydroxyphenoxathin, 2,7-dihydroxy-9,l0- dimethylphenazine, 3,6-dihydroxydibenzofuran, 3,6- dihydroxydibenzothiophene, and 2,7- dihydroxycarbazole; resorcinol, substituted resorcinol compounds such as 5-methyl resorcinol, 5-ethyl resorcinol, 5-propyl resorcinol, 5-butyl resorcinol, 5-t-butyl resorcinol, 5- phenyl resorcinol, 5-cumyl resorcinol, or the like; catechol; hydroquinone; substituted hydroquinones such as 2-methyl hydroquinone, 2-ethyl hydroquinone, 2-propyl hydroquinone, 2- butyl hydroquinone, 2-t-butyl hydroquinone, 2-phenyl hydroquinone, 2- cumyl hydroquinone, 2,3,5,6-tetramethyl hydroquinone, 2,3,5,6-tetra-t-butyl hydroquinone, chlorohydroquinone, acetoxyhydroquinone, and nitrohydroquinone. Specific aromatic diols may be selected from the group consisting of resorcinol, hydroquinone, bisphenols, and any combination thereof, in which the bisphenol is selected from bisphenol A, bisphenol F, 4,4′-biphenol, phenolphthalein, 4,4′-thiodiphenol, 4,4′-sulfonyldiphenol (also known as bisphenol S), and / or 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane. Preferably, the Ar in the formula (I) for RnhPPP is derived from bisphenol A, and R in the formula (I) for RnhPPP is a methyl group. In such an instance, the non-halogenated polyphosphonate (P2) preferably comprises, based on the total number of moles of recurring units in the nhPPP (P2), at least 80 mol %, or at least 85 mol %, or at least 90 mol %, or at least 95 mol %, or at least 97 mol %, or at least 99 mol %, or essentially 100 mol %, of recurring units (RnhPPP) of Formula (II): . of the 4 wt.% to about 16 wt.%, or from 6 wt.% to 14 wt.%, or from 8 wt.% to 12 wt.%, or from 10 wt.% to 11 wt.%, or a value between any of these ranges. Preferably, the nhPPP (P2) is prepared from bisphenol A, has recurring units (RnhPPP) of formula (II), and has a phosphorus content of from 10 to 11 wt.%. The at least one nhPPP (P2) may have a weight average molecular weight (Mw) of from 10,000 g / mole to 100,000 g / mole, preferably from 40,000 g / mole to 100,000 g / mole. The Mwmay be measure by Gel Permeation Chromatography using polystyrene calibration standards. The at least one nhPPP (P2) may have a glass transition temperature (Tg) of 100-105oC. The at least one nhPPP (P2) may have a TGA decomposition (5% in air) of at least 440oC, wherein ‘TGA’ stands for thermogravimetric analysis. Suitable but non-limiting examples of non-halogenated polyphosphonate products for the nhPPP (P2) are Nofia® polyphosphonates commercially available from FRX Polymers, Inc., Chelmsford, MA. Particularly advantageous when used in the composition (C) of the present invention are the following Nofia® polyphosphonates with some characteristics available from the supplier : o Nofia® HM7000 having a melt viscosity rate of 80 cm3 / 10 min (240oC, 1.2 kg) and of 20 cm3 / 10 min (200oC, 1.2 kg), a Tg of 105oC, a TGA decomposition 5 wt.% (air) ≥ 460oC, a phosphorous content of 10.5 wt.%; o Nofia® HM9000 having a melt viscosity rate of 25 cm3 / 10 min (240oC, 1.2 kg) and of 5 cm3 / 10 min (200oC, 1.2 kg), a Tg of 105oC, a TGA decomposition 5 wt.% (air) ≥ 460oC, a phosphorous content of 10.5 wt.%; o Nofia® HM1100 having a melt viscosity rate of 10 cm3 / 10 min (240oC, 1.2 kg) and of 2.5 cm3 / 10 min (200oC, 1.2 kg), a Tg of 105oC, a TGA decomposition 5 wt.% (air) ≥ 440oC, a phosphorous content of 10.5 wt.%. The white pigment (A1) The composition (C) further comprises from 0.1 to 15 wt.% of at least one white pigment (A1), the wt.% being based on the total weight of the composition (C). The composition (C) comprises advantageously at least 0.2 wt.%, or preferably at least 0.5 wt.%, more preferably at least 1 wt.%, still more preferably at least 3 wt.%, and even more preferably at least 4 wt.%, f the at least one white pigment (A1), based on the total weight of the composition (C). The composition (C) comprises advantageously at most 14 wt.%, preferably at most 12 wt.%, more preferably at most 10 wt.%, still more preferably at most 9 wt.%, and even more preferably at most 8 wt.%, of the at least one white pigment (A1), based on the total weight of the composition (C). The composition (C) may comprise from 0.2 wt.% to 14 wt.%, preferably from 0.5 wt.% to 12 wt.%, more preferably from 1 to 10 wt.%, still more preferably from 3 to 10 wt.% or from 3 to 9 wt.%, and even more preferably from 4 to 8 wt.%, of the at least one white pigment (A1), based on the total weight of the composition (C). When the composition (C) further comprises another inorganic and / or organic pigment as optional additive (A4) different than the at least one white pigment (A1), the total amount of pigments should fall within the content ranges specified above. The at least one white pigment (A1) in the composition (C) according to the present invention may be selected from the group consisting of titanium dioxide (rutile, anatase), barium sulfate, zinc sulfide, lithopone, titanium-zinc- mixed oxides, and any mixture thereof. Preferably, the at least one white pigment (A1) in the composition (C) may be selected from the group consisting of titanium dioxide, zinc sulfide, and any combination thereof. The at least one white pigment (A1) in the composition (C) according to the present invention preferably comprises titanium oxide. Any of the available crystalline forms (rutile, anatase) of the titanium dioxide may be used, with the rutile form being preferred due to its superior pigment properties. More advantageously, the white pigment (A1) in the composition (C) may be titanium oxide or a combination of titanium dioxide and zinc sulfide, the titanium dioxide preferably being in rutile form. Most advantageously, the white pigment (A1) in the composition (C) is titanium oxide, preferably being in rutile form. As described in notably in US 5204400 and US 5916058, titanium dioxide can be used as a pigment of poly(biphenyl ether sulfone) compositions, and it is further known that it can be profitably combined with a fluorocarbon polymer, to provide efficiently pigmented and flame-retarded compositions. Because of its possible beneficial effect on fire resistance (in combination with the nhPPP (P2)), titanium dioxide may qualify per se as an inorganic flame- retardant synergist. The weight of titanium dioxide, based on the weight of PPSU (P1), is advantageously below 8 %. The weight of titanium dioxide, based on the weight of PPSU (P1), is preferably between 2 and 6 %; more preferably, it is between 3 % and 5 %. The at least white pigment (A1) is generally in the form of solid particles. When present in the composition (C), the TiO2content, based on the total weight of the composition (C), is preferably at least 1.0 wt.%, more preferably at least 2.0 wt.% and still more preferably at least 3.0 wt.%. On the other end, the TiO2content, based on the total weight of the composition (C), is preferably at most12 wt.%, more preferably at most 10.0 % or at most 9.0 wt.%, still more preferably at most 8.0 wt.%, and most preferably at most 7.0 wt.%. Any white pigment (A1) used in the composition (C) is preferably non- halogenated. Any white pigment (A1) used in the composition (C) more preferably does not contain any halogen atom. The melt stabilizer (A2) As mentioned previously, the composition (C) may further comprise at least one melt stabilizer (A2). The melt stabilizer (A2) is preferably a metal oxide; more preferably, it is zinc oxide. The weight of the melt stabilizer (A2), relative to the weight of PPSU (P1), may be from 0.0.05 to 2.0 % ; more preferably, it may be from 0.05 to 1.0%. When zinc oxide is present as melt stabilizer (A2) in the composition (C), its content, based on the total weight of the composition (C), ranges advantageously from 0.01 wt.% to 0.5 wt.%. The zinc oxide content, based on the total weight of the composition (C), is preferably at least 0.10 wt.% and more preferably at least 0.15 wt.%. On the other end, the zinc oxide content, based on the total weight of the composition (C), is preferably at most 0.40 wt.% and more preferably at most 0.3 wt.%. More advantageously, the zinc oxide content, based on the total weight of the composition (C), is from 0.1 wt.% to 0.23 wt.%. Any melt stabilizer (A2) used in the composition (C) is preferably non- halogenated. The melt stabilizer (A2) used in the composition (C) more preferably does not contain any halogen atom. The non-halogenated flame retardant synergist (A3) The composition (C) may further comprise up to 20 wt.%, or from 0.1 wt.% to 18 wt.%, of at least one non-halogenated flame retardant synergist (A3) [ “FR synergist (A3)” ], said wt.% being based on the total weight of the composition (C). Synergistic mixtures of the nhPPP (P2) and the FR synergist (A3) should allow higher efficiency in fire resistance at lower loadings for the resulting composition (C). Nitrogen-containing compounds which can be used in the FR synergist (A3) include compounds of following formulae (III) to (VIII) or any combination thereof:

[0002] , , , are or mono- or diC1-C8alkyl amino; or C1-C8alkyl, C5-C16cycloalkyl, -alkylcycloalkyl, wherein each may be substituted by a hydroxyl or a C1-C4hydroxyalkyl, C2-C8alkenyl, C1-C8alkoxy, -acyl, -acyloxy, C6-C12aryl, -OR4and -N(R4)R5; or are N-alicyclic or N-aromatic, where N-alicyclic denotes cyclic nitrogen containing compounds such as pyrrolidine, piperidine, imidazolidine, piperazine, and the like, and N- aromatic denotes nitrogen containing heteroaromatic ring compounds such as pyrrole, pyridine, imidazole, pyrazine, and the like; R7, R8, R9, R10and R11are independently hydrogen, C1-C8alkyl, C5-C16cycloalkyl or -alkyl(cycloalkyl), each may be substituted by a hydroxyl or a C1-C4hydroxyalkyl, C2-C8alkenyl, C1-C8alkoxy, -acyl, -acyloxy, C6-C12aryl, and -O-R4; X is phosphoric acid or pyrophosphoric acid; q is 1, 2, 3, or 4; and b is 1, 2, 3, or 4. Particularly suitable nitrogen-containing compounds to be used in the FR synergist (A3) may be selected from the group consisting of benzoguanine compounds, terepthalic ester compounds of tris(hydroxyalkyl)isocyanurate, allantoin compounds, glycoluril compounds, melamine cyanurate, melamine phosphate compounds, dimelamine phosphate compounds, melamine pyrophosphate compounds, melem, melam, and combinations thereof. Preferably, suitable nitrogen compounds which may be used as non- halogenated FR synergist (A3) is a melamine containing compound. For example, the non-halogenated FR synergist (A3) may include or may be melamine cyanurate, melamine phosphate compounds (e.g., melamine polyphosphate), dimelamine phosphate compounds, melamine pyrophosphate compounds, or combination thereof. Examples of commercial melamine containing compounds may be MC-melamine cyanurate and MPP-melamine polyphosphate from JLS Chemicals. Silicone compounds as FR synergist (A3) may also be used in the composition (C). Particularly suitable siloxane-containing compounds to be used in the FR synergist (A3) may be selected from the group consisting of polyalkylsiloxanes. The polyalkylsiloxane contains more than 50 mol % of siloxane recurring units (RSil) of formula (IX): R (IX), n of one another, is a C1-C30alkyl group, preferably each R is methyl; and n is an integer from 2 to 200, preferably from 5 to 200, and wherein said mol % is based on the total number of moles of recurring units in the polyalkylsiloxane. Preferably, at least 60 mol %, at least 70 mol %, at least 80 mol %, at least 90 mol %, at least 95 mol %, at least 99 mol %, or most preferably all, of the recurring units in the polyalkylsiloxane are recurring units (RSil) of formula (IX), said mol % being based on the total number of moles of recurring units in the polyalkylsiloxane. The FR synergist (A3) may preferably comprise, or consist of, a polydimethylsiloxane homopolymer or copolymer [ hereinafter “PDMS” ]. The PDMS contains, based on the total number of moles of recurring units in the PDMS, at least 50 mol % of dimethylsiloxane recurring units (RDMSil) of formula (IX’): n (IX’), from 5 to 200. The FR synergist (A3) may more preferably comprise, or consist of, a linear PDMS homopolymer or copolymer. Examples of PDMS copolymers as FR synergist (A3) are polycarbonate- polydimethylsiloxane [ “PC-PDMS” ] block copolymers. An inorganic FR synergist (A3), particularly a metal synergist e.g., antimony oxide, may also be used in the composition (C) with the nhPPP (P2) as flame retardant. Any FR synergist (A3) used in the composition (C) preferably does not contain any halogen atom. Poly(aryl ether ketone) (P3) The composition (C) may further comprise up to 30 wt.%, of at least one poly(aryl ether ketone (P3), said wt.% being based on the total weight of the composition (C). The poly(aryl ether ketone (P3) is generally referred to as “PAEK (P3)” in the text. As used herein, a PAEK (P3) denotes any polymer comprising more than 50 mol % of recurring units (RPAEK) comprising a Ar’-C(=O)-Ar* group, where Ar’ and Ar*, equal to or different from each other, are aromatic groups. The recurring units (RPAEK) of PAEK (P3) are selected from the group consisting of units of formulae (J-A) to (J-D) below: wherein : - each the group consisting of 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; and - j’ is zero or an integer ranging from 1 to 4. In recurring unit (RPAEK), the respective phenylene moieties may independently have 1,2-, 1,4- or 1,3-linkages to the other moieties different from R’ in the recurring unit (RPAEK). Preferably, said phenylene moieties have 1,3- or 1,4- linkages, more preferably they have a 1,4-linkage. In recurring units (RPAEK), j’ is preferably at each occurrence zero so that the phenylene moieties have no other substituents than those linking the main chain of the polymer. The PAEK (P3) is preferably a poly(ether ether ketone). As used herein, a poly(ether ether ketone) [ hereinafter “PEEK” ] denotes any PAEK (P3) of which more than 50 mol % of the recurring units (RPAEK) are recurring units (RPEEK) of formula J’-A : . mol %, at least 90 mol %, at least 95 mol %, or at least 99 mol %, and most preferably all, of recurring units (RPAEK) in the PEEK are recurring units (RPEEK) of formula (J'-A). Poly(ether ether ketone)s homopolymers are notably commercially available as KetaSpire®from Solvay Specialty Polymers USA, LLC (SYENSQO group). Examples of PEEK products suitable for the PAEK (P3) are Ketaspire® PEEK KT-880 P having melt flow rate of 36 g / 10 min (400 °C / 2.16 kg ASTM D1238) or Ketaspire® PEEK KT-820 P having melt flow rate of 3 g / 10 min (400 °C / 2.16 kg ASTM D1238). Any PAEK (P3) used in the composition (C) is preferably non- halogenated. Poly(para-phenylene sulfide) (P4) The composition (C) may further comprise up to 20 wt.%, of at least one poly(para-phenylene sulfide) (P4), said wt.% being based on the total weight of the composition (C). The poly(para-phenylene sulfide) (P4) is generally referred to as “PPS (P4)” in the text. As used herein, a PPS (P4) denotes any polymer of which more than 50 mol % of the recurring units are recurring units (RPPS) of formula (L): , said total number of moles of recurring units in the PPS (P4). Preferably at least 60 mol %, or at least 70 mol %, or at least 80 mol %, or at least 90 mol %, or at least 95 mol %, or at least 99 mol %, or most preferably all, of the recurring units in the PPS (P4) are the recurring units (RPPS) of formula (L), wherein the mol% is based on the total number of moles of recurring units in the PPS (P4). PPS homopolymers are manufactured and sold under the tradename Ryton®PPS by Solvay Specialty Polymers USA, LLC (SYENSQO group). The PPS (P4) may be water washed, acid washed or not acid washed. When the PPS (P4) is acid washed, the PPS (P4) is preferably an acetic acid- washed PPS. The melt flow rate (at 316°C under a weight of 5 kg according to ASTM D1238, 2023, procedure B) of the PPS (P4) may be from 50 g / 10 min to 400 g / 10 min, for example from 60 g / 10 min to 300 g / 10 min or from 70 g / 10 min to 200 g / 10 min. The melt flow rate of the poly(para-phenylene sulfide) (P4) is measured with 5 kg load at a temperature of 316oC (ASTM D1238, 2023, procedure B). As used herein, the melt flow rate (MFR), also known as melt flow index (MFI), is used to characterize polymer melts. It is an indirect measure of molecular weight, meaning that high MFR corresponds to low molecular weight. At the same time, the melt flow rate is a measure of the ability of the material's melt to flow under pressure. The melt flow rate is inversely proportional to the viscosity of the polymer melt. If the MFI or MFR is low, then its melt viscosity and melt flow resistance is high. Suitable commercially-available products for the PPS (P4) are PPS homopolymers manufactured and sold under the tradename Ryton®PPS by Solvay Specialty Polymers USA, LLC (SYENSQO group). In the text of the application, a PPS product Ryton® starting with the prefix ‘QA’ such as QA 149A or QA 200N means an acid-washed PPS. Suitable but non-limiting examples of PPS products are Ryton® PPS QA 220N and QA 200N having a melt flow rate of 160 g / 10 min and 100 g / 10 min, respectively; and Ryton® PPS QC 220N, QC 210N and QC 200N having a melt flow rate of 175 g / 10 min, 135 g / 10 min, and 100 g / 10 min, respectively. A particular advantageous PPS is Ryton® PPS QA 149A, which has a melt flow rate of 25 – 45 g / 10 min at 316 °C, 5.0 kg. Any PPS (P4) used in the composition (C) is preferably non-halogenated. Optional other ingredient(s) (A4) The composition (C) may consist essentially of (or even, may consist of) the PPSU (P1), the nhPPP (P2), the white pigment (A1), the optional melt stabilizer (A2), the optional PAEK (P3) and / or optional PPS (P4). Alternatively, the composition (C) may further comprise one or more optional ingredient(s) (A4). In rare instances, the total weight content of the optional ingredient(s) (A4), based on the total weight of the composition (C), may be up to 30 wt.%; it is however generally below 25 wt.%, preferably below 12 wt.%, more preferably below 10 wt.%, still more preferably below 8 wt.%, and yet even more preferably below 5 wt.%. Any optional ingredient (A4) in the composition (C) is advantageously chosen from ingredients which do not detrimentally affect the beneficial properties of the composition (C). The selection of a particular additional ingredient (A4), and the amount in the composition (C), may depend upon the end use envisioned for the composition (C). The composition (C) may further include at least one other ingredient (A4) selected from the group consisting of glass fiber, carbon fiber, inorganic fiber, organic fiber, fillers, surfactants, organic binders, polymeric binders, crosslinking agents, coupling agents, anti-dripping agents, colorants (i.e., colored pigments, carbon black, and dyes), inks, antioxidants, anti-hydrolysis agents, or combinations thereof. Any optional ingredient (A4) used in the composition (C) is preferably non-halogenated. Optional colorant(s) different than white pigment (A1) In addition to the at least one white pigment (A1), the composition (C) may further comprise at least one inorganic and / or organic colorant as an optional ingredient (A4). Such colorants are well known from the skilled person and are notably chosen from : carbon black, iron oxide pigments, chromium oxide green, lead chromate molybdate pigments, cadmium pigments, mixed metal oxide pigments, or dyes such as ultramarine blue, etc. The total amounts of both the white pigment(s) (A1) and the optional colorant(s) (A4) in the composition (C) according to the present invention are preferably present in the composition (C) in an amount of at least 1 wt.%, more preferably of at least about 1.5 wt.%, yet more preferably of at least about 3 wt.%, or still more preferably of at least about 4 wt.%, based on the total weight of the composition (C). On the other hand, the total amounts of the white pigment (A1) and the optional colorant(s) (A4) are preferably present in the composition (C) in an amount of at most 35 wt.%, more preferably of at most 25 wt.%, yet more preferably of at most 15 wt.%, or still more preferably of at most 10 wt.%, and most preferably of at most 8 wt.%, based on the total weight of the composition (C). Excellent results are obtained when both white pigment(s) (A1) and optional colorant(s) (A4) are present in the composition (C) in combined amounts from 5.0 to 7.0 wt.%, or from 5.5 to 6.5 wt.%, based on the total weight of the composition (C). Any optional inorganic and / or organic colorant (A4) used in the composition (C) is preferably non-halogenated. Anhydrous zinc borate and other inorganic flame retardants The composition (C) according to the invention may optionally further comprise anhydrous zinc borate as optional ingredient (A4). The weight ratio (q1) of the anhydrous zinc borate over the nhPPP (P2) is advantageously such that 0 ^ q1 ^ 50%. As described in US 5204400, anhydrous zinc borate (i.e. zinc borate with less than 0.2 wt.% of water, and preferably with no measurable water content like XPI-187 zinc borate from U.S. Borax) is a suitable flame retardant additive for poly(biphenyl ether sulfone) compositions. The weight ratio q1 is preferably below 30%, and more preferably below 10%. Still more preferably, q1is equal to 0 ; otherwise said, the composition (C) according to the invention is then free of anhydrous zinc borate. The weight of anhydrous zinc borate, based on the weight of the PPSU (P1), is advantageously below 4.0 %, preferably below 2.0 %, and more preferably below 1.0 %. Still more preferably, the composition (C) according to the invention is free of anhydrous zinc borate, as previously described. More generally, should the composition (C) contain inorganic flame retardants, their content in the composition (C) should advantageously be low when compared to the weight of the nhPPP (P2). Accordingly, it is advantageous that the weight ratio (q’1) of the inorganic flame retardant(s) over the nhPPP (P2) is such that 0 ^ q’1 ^ 60%. The weight ratio q’1 is preferably below 30% and more preferably below 10%. The weight of inorganic flame retardant(s), based on the weight of the PPSU (P1), is advantageously below 6 %, preferably below 3 %, and more preferably below 1 %. Any anhydrous zinc borate or any other inorganic flame retardant used as optional ingredient (A4) used in the composition (C) is preferably non- halogenated. Polymers different than polymers (P1), (P2), (P3), (P4) The composition (C) is often free of any polymer different than the polymers (P1), (P2), and optional polymers (P3), (P4), described above. Yet, the composition (C) may further comprise at least one additional polymer as an optional additive (A4) which is different than the polymers (P1), (P2), (P3) and (P4), in an amount generally below 10 wt.%, based on the total weight of the composition (C). The polymer different than the polymers (P1), (P2), (P3) and (P4) may be a polymer selected from the group consisting of : (a): poly(aryl ether sulfone)s different than PPSU (P1), such as polysulfones (“PSU”), polyetherethersulfones (“PEES”) and polyethersulfones (“PES”); (b): poly(ether imide)s (“PEI”); (c): wholly aromatic polyesters ; and (d) any mixture thereof. Polyetherethersulfones, as herein defined, are polycondensation polymers of which more than 50 wt.% of the recurring units are: O OO S polymers of which more than 50 mol. % of the recurring units are: O O O SO. as VERADEL®from Solvay Specialty Polymers USA, LLC (SYENSQO group). Polysulfones, as herein defined, are polycondensation polymers of which more than 50 mol. % of the recurring units are: CH3O OO S . A polyetherimide (PEI), as herein defined, denotes any polymer of which more than 50 mol % of the recurring units (RPEI) comprise at least one aromatic ring, at least one imide group, as such and / or in its amic acid form, and at least one ether group. Preferably at least 60 mol %, 70 mol %, 80 mol %, 90 mol %, 95 mol %, 99 mol %, and most preferably all of recurring units of the PEI are recurring units (RPEI). Recurring units (RPEI) may optionally further comprise at least one amide group which is not included in the amic acid form of an imide group. The recurring units (RPEI) are advantageously of a formula selected from the group consisting of following formulae (M), (N), (O), (P), (Q), and any combination thereof : O O O O O R HOOC R O wherein, in the formulae (M) to (Q) : - Ar are tetravalent aromatic moieties and Ar’’’ are trivalent aromatic moieties independently selected from the group consisting of a substituted or unsubstituted, saturated, unsaturated or aromatic monocyclic and polycyclic group having 5 to 50 carbon atoms; and - R is a divalent radical of the general formula (S) : , (i) Y is atoms, in particular –C(CH3)2; (ii) R’’ 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; and (iii) p is independently 0, 1, 2, 3 or 4; with the proviso that at least one of Ar, Ar’’’ and R comprises at least one ether group, wherein said ether group is present in the polymer chain backbone. Polyetherimides are commercially available under the tradename ULTEM® from Sabic. Particularly suitable PEI are Ultem® 1000, 1040, 1010 and 1100 series having a glass transition temperature of 217oC. Wholly aromatic polyesters, as herein defined, are polycondensation polymers essentially all (or even, all) the recurring units of which are derived from at least one aromatic diacid and at least one aromatic diol in a molar ratio diacid:diol of about 1.00:1.00, and / or at least one aromatic monoacid– monoalcohol. Wholly aromatic polyesters are notably commercially available as XYDAR®from Solvay Specialty Polymers USA, LLC (SYENSQO group). Any polymer, different than the polymers (P1), (P2), (P3) and (P4), which may be used as optional ingredient (A4) in the composition (C), such as any of the polymers (a), (b) and (c) described above, is preferably non-halogenated. Filler and / or reinforcing agent The composition (C) may further comprise at least one solid filler and / or reinforcing agent as an optional additive (A4), in a weight amount which might be up to 30 wt.%, although being generally below 25 wt.%, based on the total weight of the composition (C). In such an instance, the composition (C) may include at least 1 wt. % or at least 5 wt.% of the solid filler and / or reinforcing agent. Fibers which may serve as reinforcing agent include, but are not limited to, glass fibers, graphitic carbon fibers, amorphous carbon fibers, synthetic polymeric fibers, aluminum fibers, aluminum silicate fibers, oxide of metals such as aluminum fibers, titanium fibers, magnesium fibers, wollastonite, rock wool fibers, steel fibers, tungsten fibers, etc. Non-fibrous reinforcing agents may include glass flakes. Representative solid fillers include glass, calcium silicate, silica, clays, talc, mica, wollastonite, graphite, aluminum trihydrate, sodium aluminum carbonate, barium ferrite and pigments such as carbon black, iron oxide, cadmium red, iron blue, and the like. Any solid filler and / or reinforcing agent as an optional which is used as optional ingredient (A4) in the composition (C) is preferably non-halogenated. Other optional ingredients (A4) The composition (C) may also further comprise additional ingredients commonly employed in the resin art such as thermal stabilizers, ultraviolet light stabilizers, smoke suppressants, plasticizers, mold release agents, impact modifiers, and the like. Any of such additional ingredient is preferably non- halogenated. METHOD FOR PREPARING THE COMPOSITION (C) The composition (C) is advantageously prepared by any conventional mixing method. The method preferably comprises melt-processing. A particular method may comprise dry mixing the ingredients of the composition (C) in powder or granular form, using e.g. a mechanical blender, then extruding the mixture into strands and chopping the strands into pellets. Accordingly, the individual ingredients, commonly provided in the form of chips, pellets and / or powders, can be physically mixed together in an appropriate apparatus such as a mechanical drum tumbler and then optionally dried, if desired, preferably under vacuum or in a circulating air oven, to remove water from the physical mixture so as to facilitate compounding; the composition may then be pelletized, for example by melt extrusion to form a strand which, upon solidification, can be broken up into chips or pellets. It is not necessary to combine all ingredients in a single operation; for example, a pigment-free composition can be compounded first with the polymers (P1) and (P2) and optional polymer (P3) and / or (P4), and melt blended with the desired amount of white pigment (A1), such as TiO2, in a later operation. A melt-blending method may be used for mixing polymeric ingredients and non-polymeric ingredients in the context of the present invention. For example, polymeric ingredient(s) (P1, P2, P3, P4, etc.) and non-polymeric ingredients (A1, A2, A3, etc.) may be fed into a melt mixer, such as single screw extruder or twin screw extruder, agitator, single screw or twin screw kneader, or Banbury mixer, and the addition step may be addition of all ingredients at once or gradual addition in batches. When the polymeric ingredient(s) and non- polymeric ingredients are gradually added in batches, a part of the polymeric ingredient(s) and / or non-polymeric ingredients is first added, and then is melt- mixed with the remaining polymeric ingredient(s) and non-polymeric ingredients that are subsequently added, until an adequately mixed composition is obtained. METHOD FOR INCREASING FIRE RESISTANCE AND FLOWABILITY OF NEAT PPSU Another aspect of the present invention is directed to a method for improving the fire resistance, flowability and ability to color-match of neat poly(biphenyl ether sulfone), which includes compounding a neat poly(biphenyl ether sulfone) (P1) with at least one non-halogenated polyphosphonate (P2), at least one white pigment (A1) and any optional ingredient(s) such as at least one melt stabilizer (A2) to form a fire-resistant high-flow composition (C), with the proviso that no halogenated flame retardant is used. Preferably, the at least one white pigment (A1) and the optional melt stabilizer (A2) are not halogenated. In such a method, up to 20 wt.% of nhPPP (P2) and up to 15 wt.% of the white pigment (A1) are melt-processed with the PPSU (P1) to form the composition (C). Any of the various embodiments described in relation to the composition (C), to any of its ingredients (including optional ingredients) and to the method of making such a composition (C) is equally applicable here. USE OF COMPOSITION (C) Another aspect of the present invention is directed to the use of the composition (C) according to the invention for manufacturing an article. Any of the various embodiments described in relation to the composition (C) and / or to any of its ingredients (including optional ingredients) is equally applicable here. ARTICLE Another aspect of the present invention is directed to a shaped article comprising, or made from, the polymer composition (C) as above described. Any of the various embodiments described in relation to the composition (C) and to any of its ingredients (including optional ingredients) is equally applicable here. Preferably, the inventive shaped article comprises more than 50 wt.% of the composition (C). The shaped article may consist essentially of (or may even consist of) the composition (C). The invented shaped article may comprise one or more parts. More than 50 wt.% of at least one part of the invented shaped article may be comprised of the composition (C). The invented shaped article may comprise at least one part consisting essentially of (or even consisting of) the composition (C). The shaped article according to the present invention is advantageously used notably anywhere where high fire resistance, and / or high flowability (low melt viscosity at high shear rate), for thin-wall parts and consequently for light- weight aircraft interior components) are important. The shaped article according to the present invention can be a three- dimensional article, a fiber, a film, a tape, a sheet (which may be suitable for use in laminating and for coating applications) or a slab. The shaped article according to the present invention can be fabricated according to the known methods in the field, for example, forming the article using injection molding or extrusion. The shaped article according to the present invention is preferably an aircraft component, more preferably an aircraft interior component. Still more preferably, the shaped article is an aircraft interior component selected from the group consisting of overhead passenger service units, stowage compartments, galley structures, window reveals, air return grills, ceiling panels, wall panels, overhead storage lockers, serving trays, seat backs, cabin partitions, and ducts. APPLICATIONS A last aspect of the present invention concerns an aircraft comprising at least one aircraft component. The aircraft component may be any of the above- described aircraft components. 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 invention. EXAMPLES The invention will now be described with reference to the following examples, whose purpose is merely illustrative and not intended to limit the scope of the invention. As used in the Examples, “E” denotes an example embodiment of the present invention and “CE” denotes a counter-example. The following examples demonstrate the unexpected merits of the polymer composition (C) according to the present invention. Exemplified polymer compositions Seventeen (17) polymer compositions were prepared, five (5) polymer compositions as comparative examples (named CE1 to CE6) and twelve (12) polymer compositions in accordance with the present invention (named E7 to E17). The nature and amount of the ingredients for each composition are detailed in Tables 2-4 hereinafter, together with the results obtained herewith. Preparation of the polymer compositions The melt-blending was carried out using a Coperion® ZSK-26 co-rotating twin-screw extruder and the compounded samples were subsequently molded according to ASTM D3641. Prior to mixing the polyphosphonate in the exemplified compositions, the polyphosphonate (P2) was dried prior to melt processing so as to achieve < 50- 200 ppm moisture. The drying step was carried out at 95oC for at least 6 hours. The presence of moisture could hydrolyse this polymer in the melt phase at high temperature (e.g., 220oC) thereby reducing its molecular weight. The polymer compositions were extruded at a melt temperature of 360° C. The first vent port was open to the atmosphere while the second vent port was connected to a vacuum pump. The strands were then passed through a water trough for cooling and then pelletized. Raw Materials The raw materials used to form the samples as provided below in Table 1. Table 1 Abbr.Raw materials Sources(P1) RADEL®R-5600 NT is a natural grade of Solvay Specialty PPSU polyphenylsulfone homopolymer (PPSU), with a Polymers USA heat deflection temperature of 236° C and a melt (SYENSQO) flow in the range of 30 to 40 g / 10 min at 365 ° C and under a 5.0 kg load Available in powder and / or pellet form (P2-A) Nofia® HM1100 having a melt viscosity rate (240oFRX Polymers PPP C, 1.2 kg) of 10 cm3 / 10 min, a Tg of 105oC, a phosphorous content of 10.5 wt.% (P2-B) Nofia® HM9000 having a melt viscosity rate (240oFRX Polymers PPP C, 1.2 kg) of 25 cm3 / 10 min, a Tg of 105oC, a phosphorous content of 10.5 wt.% (P2-C) Nofia® HM7000 having a melt viscosity rate (240oFRX Polymers PPP C, 1.2 kg) of 80 cm3 / 10 min, a Tg of 105oC, a phosphorous content of 10.5 wt.%. (A1) Ti-Pure® R-105 rutile titanium dioxide Chemours TiO2 (A2) ZOCO 102 Zinc Oxide UNIVAR ZnO SOLUTIONS USA INC – Nexeo Solutions (P3) PEEK Ketaspire® 880 is a polyetheretherketone Solvay Specialty PEEK (PEEK), with a melt flow rate in the range of 36 Polymers USA g / 10 min (400° C ; 2.16 kg load via ASTM D1238) (SYENSQO) in powder and / or pellet form. (P4) PPS Ryton® QA149A is a polyphenylsulfide with a Solvay Specialty PPS melt flow rate in the range of 25 – 45 g / 10 min at Polymers USA 316 ° C and under a 5.0 kg load (ASTM 1238) in (SYENSQO) powder and / or pellet form. ZnB Zinc borate Smokeshield ZB5 St. Louis Group PTFE POLYMIST®F5A is a micronized, non fibrillating Solvay Specialty polytetrafluoroethylene having a melt flow index of Polymers Italy 20 g / 10 min measured at 380°C and under a 21 kg (SYENSQO) load MFA HYFLON®MFA 1041 is a tetrafluoroethylene- Solvay Specialty perfluoromethylvinylether copolymer with a melt Polymers Italy flow rate of about 18.3 g / 10 min (ASTM D1238) (SYENSQO) Test methods ^ Tensile properties – ASTM D-638 (2022) The tensile properties (yield strength, yield elongation, elongation at break and tensile modulus) were measured on 5 injection-molded standard 3.2 mm (0.125 in) thick ASTM test specimens. ^ Flexural properties (strength and modulus) - ASTM D790 (2017) The flexural properties (strength and modulus) were measured on 5 injection- molded standard 3.2 mm (0.125 in) thick ASTM test specimens. ^ Notched Izod impact strength – ASTM D256 (2023) Notched Izod impact strength was measured in J / m on 5 injection-molded, rectangular bars having dimensions of 3.2 mm thickness by 12.7 mm width by 125 mm length. ^ OSU Heat Release A heat calorimetry testing methodology developed at Ohio State University, known as the OSU Flammability Test, was used to determine whether the polymer compositions met U.S. government air worthiness standards. The OSU tests measure the two minute total heat release (“2-min THR”) and the peak heat release rate (“Maximum HRR”), expressed in kilowatt times minutes per square meter of surface area (kW-min / m²) and kilowatt per square meter of surface area (kW / m²) respectively, for the first five minutes of a burn test under the conditions of the OSU testing. More precisely, the heat release properties of the polymer compositions were evaluated in accordance with FAR 25.853 Amendment 25-83, Appendix F, Part IV. The “Part IV—Test Method To Determine the Heat Release Rate From Cabin Materials Exposed to Radiant Heat” is accessible via the following internet link: https: / / www.ecfr.gov / current / title-14 / chapter-I / subchapter-C / part-25 / appendix- Appendix%20F%20to%20Part%2025. Specimens were prepared by injection molding plaques of following dimensions: 15 cm x 15 cm x 0.2 cm (6 in x 6 in x 0.080 in) from the compositions in a Mitsubishi molding press. The samples were mounted vertically in an enclosed chamber and exposed to flame by multiple pilots mounted at the top and bottom of the sample fixture. The samples were simultaneously exposed to a radiant heat flux of 3.5 W / cm2and 2.4 m3 / min (85 ft3 / min) airflow. The heat released during combustion was determined by measuring the difference in temperature of the effluent air from the inlet air. To pass the OSU test, the total 2- minute heat release (2-min THR) and the maximum heat release rate (Max. HRR) should not exceed 65 KW•min / m2and 65 KW / m2, respectively regulated by FAR 25-853(d). ^ Rheology - ASTM D3835 (2016) Melt viscosity measurements were made using a Kayeness®capillary rheometer in accordance with ASTM D3835. 20 g samples of the polymer compositions were dried at 160°C for 2 hours prior to testing. The samples were loaded into the barrel and allowed to melt. A motor driven crosshead with a load transducer used a packing force of 2224 N to drive a piston through a heated steel cylinder maintained at a temperature of 380°C. The sample was forced through a 1.02 mm (0.040 in) diameter, 20.32 mm (0.800 in) long die with an entrance angle of 120° at a controlled rate. The rate and force exerted by the sample were used to calculate the viscosity ^100of the polymer composition at a given shear rate of -1 100 s . ^ Thermal - glass transition point Tg(DSC) Differential Scanning Calorimeter (DSC) was used to determine glass transition temperatures (Tg). DSC experiments were carried out using a TA Instrument Q100. DSC curves were recorded by heating, cooling, re-heating, and then re- cooling the sample between 25°C and 320°C at a heating and cooling rate of 20°C / min. All DSC measurements were taken under a nitrogen purge. The reported Tg values were provided using the second heat curve unless otherwise noted. Results. All the results are provided in Tables 2-4. Table 2FormulationsUnits CE1 CE2 CE3 CE4 CE5 CE6(P1) PPSUwt.% 100 91 91.5 92.5 61 90(P2-A) PPP HM7000wt.% 10(A1) TiO2wt.% 6 6 6 6(P4) PPSwt.% 30ZnBwt.% 1 1 1 1PTFEwt.% 1.5 1.5 2MFAwt.% 0.5 0.5Mechanical Properties Tensile PropertiesYield Strengthkpsi 10.9 10.9 10.9 11.0 11.7 13.8*MPa 75 75 75 76 81 95Yield Elongation% 8 7.5 7.5 7.5 6.8 6.9Elongation at break% 63 30 32 38 63 10Tensile Moduluskpsi 333 365 363 365 394 398*MPa 2296 2517 2503 2517 2717 2744Flexural PropertiesFlexural Strengthkpsi 14 15 15 15.3 16.4 18.8*MPa 97 103 103 105 113 130Flexural Moduluskpsi 345 382 380 381 402 414*MPa 2379 2634 2620 2627 2772 2854Impact Properties Notched Izod Impact 11.8 (complete break) ft•lb / in (partial 1.7 1.8 1.94 1.79 1.04 break) **J / m 630 91 96 104 96 56Thermal PropertiesTg onset (2nd heat, DSC) oC 218 n / a n / a n / a n / a 159OSU Heat ReleaseMaximum HRRkW / m265.6 36.0 45.9 47.2 48.2 43.92 min THR kW.min / m26.8 0.9 3.9 8.3 1.2 3.1Pass / FailFail Pass Pass Pass Pass PassRheologyMelt viscosity temp. oC 380 380 380 380 340^100at shear rate=100 s-1Pa.s n / a 479.7 730.4 715.2 394.4 621.1Impact on rheology + (comment) - -- -- (temp. too ++ high) n / a: not available * Conversion: 1 kpsi = 6,89476 MPa ; ** Conversion: 1 ft•lb / in = 53.3787 J / m Table 3 Formulations Units E7 E8 E9 E10 E11 E12 (P1) PPSU wt.% 83.77 78.77 83.77 83.77 83.77 78.77 (P2-A) PPP HM7000 wt.% 10 15 10 (P2-B) PPP HM9000 wt.% 10 10 15 (A1) TiO2wt.% 6 6 6 6 6 6 (A2) Zinc Oxide wt.% 0.23 0.23 0.23 0.23 0.23 0.23 Mechanical Properties Tensile Properties Yield Strength kpsi 12.3 12.4 12.3 12.4 12.4 12.5 * MPa 85 85.5 85 85.5 85.5 86 Yield Elongation % 6.3 5.5 6.2 6.7 6.7 6.6 Break Elongation % 10 8 11 11 15 23 Tensile Modulus kpsi 413 433 415 397 397 407 * MPa 2848 2985 2861 2737 2737 2806 Flexural Properties Flexural Strength kpsi 18.6 19.6 19.0 17.5 17.6 17.9 * MPa 128 135 131 121 121 123 Flexural Modulus kpsi 428 447 432 410 409 419 * MPa Impact Properties Notched Izod Impact ft•lb / in 1.49 1.2 1.46 1.51 1.55 1.34 ** J / m 80 64 78 81 83 72 Thermal Properties Tgonset (2nd heat, DSC)oC 172 185 176 186 195 196 OSU Heat Release Maximum HRR kW / m253.6 43.8 38.8 49.7 55.4 51.1 2-min THR kW.min / m28.8 5.9 6.4 5.7 8 7.2 Pass / Fail Pass Pass Pass Pass Pass Pass Rheology Melt viscosity temp.oC 340 340 340 340 340 340 ^100at shear rate=100 s-1Pa.s 962.5 719.7 949.5 958.3 1015 742.1 Impact on rheology + ++ + + + ++ * Conversion: 1 kpsi = 6,89476 MPa ; ** Conversion: 1 ft•lb / in = 53.3787 J / m

[0003] Table 4FormulationsUnits E13 E14 E15 E16 E17(P1) PPSUwt.% 83.77 78.77 68.77 53.77 63.77(P2-C) PPP HM1100wt.% 10 15 10 10 10(A1) TiO2wt.% 6 6 6 6 6(A2) Zinc Oxidewt.% 0.23 0.23 0.23 0.23 0.23(P3) PEEKwt.% 15 30(P4) PPSwt.% 20Mechanical Properties Tensile PropertiesYield Strengthkpsi 12.5 12.5 12.7 13.1 n / a*MPa 86 86 88 90 n / aYield Elongation% 6.7 6.6 6.4 5.8 n / aBreak Elongation% 23 24 12 13 5.3Tensile Moduluskpsi 402 409 411 451 429*MPa 2772 2820 2834 3110 2958Flexural PropertiesFlexural Strengthkpsi 17.8 18.1 18.3 19.3 18.9*MPa 123 125 126 133 130Flexural Moduluskpsi 412 421 426 459 452*MPa 2840 2903 2937 3165 3116Impact PropertiesNotched Izod Impactft•lb / in 1.55 1.28 1.22 1.22 0.761**J / m 83 68 65 65 41Thermal PropertiesTgonset (2nd heat, DSC) oC 195 195 n / a n / a n / aOSU Heat ReleaseMaximum HRRkW / m253.5 51.2 56.8 54.1 56.32 min THR kW.min / m25.3 7.5 8 8.1 13.8Pass / FailPass Pass Pass Pass PassRheologyMelt viscosity temp. oC 340 340 340 340 340^100at shear rate=100 s-1Pa.s 1010 708.4 1256 5558 1161Impact on rheology + - + (comment) + ++ (temp. (temp (temp. too too too low) low) low) n / a: not available * Conversion: 1 kpsi = 6,89476 MPa ; ** Conversion: 1 ft•lb / in = 53.3787 J / m Keys to interpret the results These keys, in the form various desirable levels of properties to be achieved, are based on the Applicant’s practical high experience and / or the requirements as set forth by its customers, e.g. manufactures of aircraft parts. For a polymer composition to be fully satisfactory, each of its properties should be at a level equal to or higher than the minimum level, as herein defined. Polymer compositions of which one or more of these properties do not reach the desirable levels have substantial chances not to be approved by the end users (as not compliant to the customers’ specs), or even to lamentably fail when effectively used in certain practical applications. Certain properties are more important than others; precisely, hereinbelow, a symbol (++, + or -) has been mentioned into brackets to the right of each property to indicate how important this property is : “++” means “very important”, “+” means “important” and “-” means “of low importance”. The nature and amount of each of the ingredients contained in the inventive compositions result from complex and careful optimization trials made by the Applicant to achieve the most suitable balance of properties. Given the requirements detailed below, the burden appeared very heavy, with very weak chances of success on the basis of the prior art teachings. If finally successful results could be obtained by the Applicant at the intended, this is notably because the invented polymer compositions exhibited some really unexpected advantageous behavior, with synergetic effects being observed. ^ (Tensile) yield strength (++) : the desirable level is typically of at least 55 MPa (8,000 psi), with values of at least 69 MPa (10 kpsi) being preferred. ^ Yield elongation (+) : the desirable level is typically of at least about 5 %. ^ Break elongation (-) : essentially no minimum desirable level. ^ Tensile modulus (++) : the desirable level is typically of at least 1724 MPa (250 kpsi). ^ Flexural strength (++) : the desirable level is typically of at least 82.7 MPa (12 kpsi), with values of at least 93 MPa (13.5 kpsi) being preferred. ^ Flexural modulus (++) : the desirable level is typically of at least 2068 MPa (300 kpsi). ^ Notched Izod impact (++) : the desirable level is typically at least 53.4 J / m (1.0 ft•lb / in). ^ 2-min THR and Maximum HRR at OSU Heat Release test (++) : the most recent airworthiness standards, enacted in 1990, for engineering thermoplastics require that both 2-min THR (in kW•min / m2), and Maximum HRR (in kW / m2) have values of 65 or less ; moreover, in the future, airworthiness standards are likely to become still stricter, leading to a further lowering of permissible 2-min THR and / or maximum HRR values ; having this in mind, it is desirable that both 2-min THR (in kW•min / m2), and maximum HRR (in kW / m2) have values of 55 or less, or of 50 or less. ^ ^100 measured at medium shear rate (100 s-1) (++) : it is desirable that the melt viscosity measured at a melt temperature which is within typical processing (molding) temperatures for PPSU based compositions, such as at 340oC, be as low as possible while maintaining all other material properties. For certain particular applications, this is especially important to reduce the composition melt viscosity when extremely thin parts have to be molded from such a PPSU based composition. In that respect, the compositions CE2 to CE4 containing fluorinated polymers (PTFE and / or MFA) are considered benchmarks; materials with similar melt viscosities when measured at the same melt temperature and shear rate are considered acceptable, while materials having similar melt viscosity when measured at a lower melt temperature and same shear rate is preferred.   Interpretation of the results PTFE-based and / or MFA-based polymer compositions CE2 to CE4 exhibit a much too high melt viscosity ^100, which makes them generally difficult to handle for manufacturing thin-walled, and consequently light-weight, aircraft interior components. When TiO2as (A1) and ZnO as (A2) were added to the combination of PPSU as (P1) and nhPPP (P2), this resulted in an increase in melt viscosity – see CE6 vs. E7-E16. However, it was observed that increasing the nhPPP content when TiO2as (A1) and ZnO as (A2) were present, reduced the melt viscosity of the resulting PPSU based compositions – see for example comparison of sample E7 versus sample E8, comparison of sample E11 versus sample E12, and comparison of sample E13 versus sample E14. It was also observed that while the composition containing only PPSU and nhPPP (CE6) had excellent fire resistant with a maximum HRR of 43.9 kW / m2, the resulting onset glass transition point Tg was low (159oC). When TiO2 as (A1) and ZnO as (A2) were added to the combination of PPSU (P1) and nhPPP (P2), this resulted in an increase in the onset glass transition point Tg ranging from 172oC to 196oC in samples E7-E14, which was about 20 to 40oC less than the neat PPSU (218oC) – see sample CE1. Overall, examples E7 to E17 demonstrated that these composition variations resulted in mechanical and thermal properties that were comparable to those of the benchmark compositions CE2 to CE4, which contained MFA and / or PTFE, and composition CE6, which contains only PPSU (P1) and nhPPP (P2). The addition of PEEK or PPS in samples E15 to E17 did not exhibit as clear a rheological improvement at lower temperature compared with other samples, however maintenance of other properties (e.g., mechanical and thermal properties) was quite notable. Furthermore, it was observed that injection molding of the sample CE5, despite its lower melt viscosity, was more challenging to achieve homogeneous appearance in molded parts. In contrast, there was no such issue when injection molding the samples E15 to E17. All references, patents, applications, tests, standards, documents, publications, brochures, texts, articles, etc. mentioned herein are incorporated herein by reference. Where a numerical limit or range is stated, the endpoints are included. Also, all values and subranges within a numerical limit or range are specifically included as if explicitly written out. Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. What is claimed is:

Claims

C L A I M S 1 - A composition (C) comprising the following ingredients: - at least one poly(biphenyl ether sulfone) (P1) [hereinafter “PPSU (P1)”], - at least one non-halogenated polyphosphonate (P2) [hereinafter “nhPPP (P2)”]; and - at least one white pigment (A1). 2 – The composition (C) according to claim 1, comprising the following ingredients: - between 60 wt.% and 94 wt. % of the at least one PPSU (P1), - from 5 wt.% to 20 wt.% of the at least one nhPPP (P2), - from 1 to 10 wt.% of the at least one white pigment (A1), and - from 0 wt.% to 1 wt.% of at least one melt stabilizer (A2), wherein the wt.% of each ingredient is based on the total weight of the composition (C), and wherein the combined weight from the ingredients (P1), (P2), (A1), (A2) is less than or equal to 100 wt.% based on the total weight of the composition (C). 3 – The composition (C) according to claim 1, comprising the following ingredients: - between 60 wt.% and 90 wt.% of the at least one PPSU (P1), - from 8 wt.% to 16 wt.% of the at least one nhPPP (P2), - from 1 to 8 wt.% of the white pigment (A1), - from 0.05 to 1 wt.% of at least one melt stabilizer (A2), - from 0 wt.% to 30 wt.%, of at least one PAEK (P3) and / or at least one PPS (P4), - from 0 wt.% to 20 wt.% of a non-halogenated flame retardant synergist (A3), and - from 0 wt.% to 5 wt.% of other additives (A4), wherein the wt.% of each ingredient is based on the total weight of the composition (C), andwherein the combined weight from the ingredients (P1), (P2), (A1), (A2), (P3), (P4), (A3), (A4) is less than or equal to 100 wt.% based on the total weight of the composition (C). 4 – The composition (C) according to any one of claims 1 to 3, having a phosphorus content of from 0.1 wt.% to 5.0 wt.%, or from 0.2 wt.% to 4.0 wt.%, or from 0.5 wt.% to 3.0 wt.%, or from 0.8 wt.% to 2.5 wt.%. 5 – The composition (C) according to any one of claims 1 to 4, wherein the PPSU (P1) has more than 50 mol %, or at least 60 mol %, or at least 70 mol %, or at least 80 mol %, or at least 90 mol %, or at least 95 mol %, or at least 99 mol %, of recurring units (RPPSU) of formula (K): O OO S, whereinunits in the PPSU (P1). 6 – The composition (C) according to any one of claims 1 to 5, wherein the PPSU (P1) has a MFR of at least 25 g / 10 min, or at least 27 g / 10 min, or at least 30 g / 10 min, or at least 34 g / 10 min, said MFR being measured with 5 kg load at a temperature of 365oC according to ASTM D1238 (2023). 7 – The composition (C) according to any one of claims 1 to 6, wherein the nhPPP (P2) is a polymer having more than 50 mol %, or at least 60 mol %, or at least 70 mol %, or at least 80 mol %, or at least 90 mol %, or at least 95 mol %, or at least 99 mol %, of recurring units (RnhPPP) of formula (I): , of moles of recurring units in thewherein in the formula (I), Ar is an aromatic group; R is a C1-20 alkyl, C2- 20 alkene, C2-20 alkyne, C5-20 cycloalkyl, or C6-20 aryl; and n may be an integer from 2 to about 200; and wherein the linking group Ar and the group R in the formula (I) do not contain any halogen atom. 8 – The composition (C) according to any one of claims 1 to 7, wherein the nhPPP (P2) has a phosphorus content, expressed in terms of wt.% based on the total weight of the nhPPP (P2), in the range from 2 wt.% to 18 wt.%, or from 4 wt.% to about 16 wt.%, or from 6 wt.% to 14 wt.%, or from 8 wt.% to 12 wt.%, or from 10 wt.% to 11 wt.%, or a value between any of these ranges; and / or wherein the nhPPP (P2) has a glass transition temperature of 100-105oC and has a TGA decomposition (5% in air) of at least 440oC. 9 – The composition (C) according to any one of claims 1 to 8, wherein the nhPPP (P2) comprises at least 80 mol %, or at least 85 mol %, or at least 90 mol %, or at least 95 mol %, or at least 97 mol %, or at least 99 mol %, of recurring units (RnhPPP) of Formula (II): , units in the. 10 – The composition (C) according to any one of claims 1 to 9, wherein the white pigment (A1) is selected from the group consisting of titanium dioxide (rutile, anatase), barium sulfate, zinc sulfide, lithopone, titanium-zinc-mixed oxides, and any mixture thereof; preferably selected from the group consisting of titanium dioxide, zinc sulfide, and any combination thereof; more preferably selected from titanium oxide or a combination of titanium dioxide and zinc sulfide.11 – The composition (C) according to any one of claims 1 to 10, wherein a melt stabilizer (A2) is present in the composition (C) and is a metal oxide, preferably zinc oxide. 12 – A method for manufacturing the composition (C) according to any one of claims 1 to 11, comprising melt-processing the ingredients (P1), (P2), (A1), and any optional ingredient(s), preferably via melt-blending or extrusion. 13 – A shaped article comprising the composition (C) according to any one of claims 1 to 11, being an aircraft interior component, preferably selected from the group consisting of overhead passenger service units, stowage compartments, galley structures, window reveals, air return grills, ceiling panels, wall panels, overhead storage lockers, serving trays, seat backs, cabin partitions, and ducts.

14. A method for improving the properties related to fire resistance, melt flowability and ability to color-match of a neat poly(biphenyl ether sulfone), said method comprising compounding a neat poly(biphenyl ether sulfone) (P1) with at least one non-halogenated polyphosphonate (P2), at least one white pigment (A1), and any optional ingredients to form the composition (C) according to any one of claims 1 to 11, with the proviso that no halogenated flame retardant is used in the composition (C).

15. Use of the composition (C) according to any one of claims 1 to 11 to make a shaped article, particularly an interior aircraft component, using injection molding or extrusion.

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