Single material objects, in particular recyclable objects, and recycling thereof

Abstract

The invention relates to a single-material object, in particular a recyclable object, consisting essentially of a long-chain polyamide, comprising at least two elements:-at least one first element consisting of at least one extruded or blow-molded part intended for transporting, dispensing and / or storing fluids,-at least one second element consisting of at least one extruded or blow-molded part intended for transporting, dispensing and / or storing fluids, the invention relates to a first element comprising at least one layer consisting of a first composition comprising at least 30% by weight, relative to the total weight of the first element, of at least one homopolyamide or copolyamide having a C / N ratio greater than or equal to 8,-at least one second element consisting of at least one injected part, the injected part consists of a second composition comprising at least 30% by weight, relative to the total weight of the second element, of at least one homopolyamide or at least one copolyamide as defined for the first composition, and the first element and the second element can be at least partially adhered to each other.

Description

TECHNICAL FIELD

[0001] The present invention relates to single material objects, notably recyclable single material objects, comprising at least two elements, to methods for manufacturing them and for recycling them, and to compositions thus obtained and their use in the manufacture of objects, in particular single material objects. BACKGROUND

[0002] Through the circular economy, it is possible to limit the generation of waste, the consumption of earth resources and the environmental impact. There is a particular interest today in producing objects through materials that, after recycling, will have properties sufficient to enable them to be used for high-performance applications and not only for lower-performance applications, such as for street furniture or roads.

[0003] In order to facilitate the recycling of components allowing the transport, distribution and / or storage of fluids in different means of transport (saloon cars, trucks, drones, etc.), equipment manufacturers wish to ecologically design their products to improve their recyclability (connectors comprising a majority of polyamide, pipes comprising a majority of polyamide, etc.).

[0004] In order to facilitate their recycling, patent EP 3 081 109 B1 proposes a sports shoe whose upper part and sole are formed mainly or even entirely from the same thermoplastic base material.

[0005] Patent application WO 2020 / 201370 A1 proposes a method for recycling a sports shoe, in which the shoe is ground and then melted. As with the previous document, the document focuses on thermoplastic polyurethane (TPU).

[0006] Patent application US 2017 / 0151470 A1 relates to a ball, in particular a football, and to a method for manufacturing and recycling the ball. The ball is composed of a bladder, an intermediate layer and an outer layer, the bladder and the two layers being composed of a first type of material of the main weight component, the material being chosen from polyurethane, polyvinyl chloride, polyethylene, polyamide and polypropylene.

[0007] International patent application WO 2021 / 148148 A1 relates to a lined apparel article comprising an outer layer, an inner layer and a lining between the two layers.

[0008] Each layer contains a major amount of material from a class chosen from thermoplastic polymers, notably recycled polyesters or virgin polymers chosen from thermoplastic polyurethane (TPU), polyamide (PA), polyethylene terephthalate (PET) or polybutylene terephthalate (PBT). Polyesters have the drawback of being very sensitive to hydrolysis.

[0009] All these patent applications above relate only to sports shoes, sports balls or clothing items and not to components allowing the transport, distribution and / or storage of fluids in different transport means. SUMMARY

[0010] It is therefore the object of the present invention to propose a single material object, notably a recyclable single material object, so as to be able to obtain, upon recycling, a composition which can be used for the manufacture of objects, notably single material objects, or for the manufacture of systems for the transport, distribution and / or storage of fluids.

[0011] In particular, in the case of systems for the transport, distribution and / or storage of fluids, notably in the case of systems for devices having thermal or electric engines, such as airplanes, drones, aircraft, trucks or motor vehicles, separating the various elements constituting said systems, notably tubes, tanks and connectors or other injection-moulded parts, in view of their sorting and their possible recycling, is generally labor-intensive and / or expensive. These separation and sorting steps, which must be performed manually by an operator, do not currently allow recycling these materials quantitatively and thus in an economically viable manner.

[0012] The need to separate and sort these different elements is therefore the main obstacle to their current recycling.

[0013] The object of the present invention is to solve this problem by providing a particular single material element which makes it possible to overcome these difficulties.

[0014] The present invention therefore relates to a single material object, notably a recyclable single material object, consisting essentially of long chain polyamides, comprising at least two elements:

[0015] - at least one first element consisting of at least one extruded or extrusion blow-moulded part intended for the transport, distribution and / or storage of fluids, notably chosen from tubes and tanks, comprising at least one layer consisting of a first composition comprising at least 30% by weight, notably at least 50%, in particular at least 70%, more particularly at least 90%, relative to the total weight of the first element, of at least one homopolyamide or at least one copolyamide, the C / N ratio of said at least one homopolyamide or at least one copolyamide of the first composition being greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10,

[0016] said at least one homopolyamide and said at least one copolyamide, independently of one another, denote a repeating unit chosen from units obtained by polycondensation of at least one C4-C 36 amino acid, units obtained by polycondensation of at least one C4-C 36obtained from the polycondensation of lactams and XY units obtained from the polycondensation of:

[0017] - at least one diamine chosen from linear or branched aliphatic diamines, cycloaliphatic diamines and semi-aromatic aliphatic diamines, or mixtures thereof, and

[0018] at least one dicarboxylic acid chosen from:

[0019] aliphatic, cycloaliphatic and aromatic diacids or mixtures thereof,

[0020] said diamine and said diacid comprising from 4 to 36 carbon atoms, advantageously from 6 to 18 carbon atoms,

[0021] - at least one second element consisting of at least one injection-moulded part, in particular chosen from connectors, said injection-moulded part consisting of a second composition comprising at least 30%, notably at least 50%, in particular at least 70%, more particularly at least 90%, by weight relative to the total weight of the second element, of at least one homopolyamide or at least one copolyamide as defined above for the first composition,

[0022] and said first element and second element being capable of adhering at least partially to one another.

[0023] The term "single-material object" is understood to mean an object consisting essentially of the same material, in this case long-chain polyamide.

[0024] More precisely, the term "single-material object" is understood to mean an object comprising at least two elements, each element consisting of a composition comprising at least one polymeric matrix, respectively, wherein said polymeric matrix comprises essentially, i.e. more than 50% by weight relative to its total weight, at least one long-chain polyamide as defined according to the invention.

[0025] For the purposes of the present invention, a single-material object can in particular be an object comprising at least two elements, each element being single-material, i.e. each element consisting essentially of the same material as defined according to the invention.

[0026] The term "polymeric matrix" is intended to denote the part of the composition consisting only of polymers, i.e. excluding here non-polymeric fillers and additives.

[0027] Preferably, said polymeric matrix comprises at least 60% by weight, preferably at least 80% by weight, preferably at least 90% by weight, advantageously at least 95% by weight, or even 100% by weight of at least one long-chain polyamide as defined according to the invention.

[0028] According to one embodiment, for the purposes of the present application, a "single material object" is an object comprising at least two elements, wherein at least one element, preferably each element, consists of a composition comprising at least 50% by weight, relative to their total weight, of at least one long chain polyamide as defined according to the present application.

[0029] Preferably, at least one element, preferably each element, consists of a composition comprising at least 80% by weight, preferably at least 90% by weight, advantageously at least 95% by weight, or even 100% by weight, of at least one long chain polyamide as defined according to the present application.

[0030] According to one embodiment, the single material object of the present application is an object comprising at least two elements, wherein at least one element, preferably each element, consists of a composition comprising less than 20% by weight, preferably less than 10% by weight, for example less than 5% by weight, for example less than 3% by weight, in particular 0% by weight, of short chain polyamides, i.e. polyamides having a C / N ratio strictly less than 8, notably less than or equal to 7, in particular less than or equal to 6.

[0031] According to one embodiment, the single material object of the present application comprises less than 20% by weight, preferably less than 10% by weight, for example less than 5% by weight, for example less than 3% by weight, in particular 0% by weight, of short chain polyamides, i.e. polyamides having a C / N ratio strictly less than 8, notably less than or equal to 7, in particular less than or equal to 6, relative to its total weight.

[0032] The expression "single material object, notably a recyclable single material object, consisting essentially of long chain polyamides" means for example that said object consists of a single kind of material and that it comprises at least 50% by weight of long chain polyamides having a C / N ratio (i.e. average number of carbon atoms per nitrogen atom) greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10.

[0033] According to one embodiment, the first element of said single material object of the present application can consist of at least one extruded or extrusion blow-molded part intended for the transport, distribution and / or storage of a fluid, said part being chosen from the group consisting of a pipe and a tank. Said pipe or tank can comprise from one to five layers.

[0034] In one embodiment, said pipe or tank comprises only a polyamide layer.

[0035] According to one embodiment, the first element of the single material object of the application comprises at least 60% by weight, in particular at least 70% by weight, notably 80% by weight, advantageously 90% by weight, more advantageously 100% by weight of long chain polyamide.

[0036] When the first element of the single material object of the application comprises less than 100% by weight of long chain polyamide, the remaining up to 100% is made of another polyamide which can or can not have long chains or of another polymer such as EVOH (ethylene-vinyl alcohol).

[0037] Advantageously, the single material object of the application comprises at least 60% by weight, in particular at least 70% by weight, notably 80% by weight, advantageously 90% by weight, more advantageously 100% by weight of long chain polyamide.

[0038] When the object comprises less than 100% by weight of long chain polyamide, the remaining up to 100% is made of another polyamide which can or can not have long chains or of another polymer such as EVOH (ethylene-vinyl alcohol).

[0039] In one embodiment, the copolyamide bearing amide units (Bal) and polyether units (Ba2) is excluded from the first composition.

[0040] In another embodiment, the copolyamide bearing amide units (Bal) and polyether units (Ba2) is excluded from the second composition.

[0041] In yet another embodiment, the copolyamide bearing amide units (Bal) and polyether units (Ba2) is excluded from the first composition and from the second composition.

[0042] Advantageously, the single material object as defined above is chosen from the group consisting of motor vehicle, truck, aircraft and drone parts.

[0043] The term "fluid" means air, oil (for example for cooling automatic gearboxes ("TOC", transmission oil cooler)), water, urea solution, refrigerant (refrigerant liquid), in particular R1234yf, glycol-based coolant (coolant liquid), fuel, for example gasoline, in particular bio-gasoline or diesel, in particular bio-diesel, hydrogen or coolant, in particular battery or fuel cell coolant (coolant liquid).

[0044] In one embodiment, the fluid is a coolant (coolant liquid), in particular a battery or fuel cell coolant (coolant liquid).

[0045] In another embodiment, the fluid is hydrogen.

[0046] According to one embodiment, the second element of the mono-material object according to the invention may consist of at least one injection-molded part intended for transporting, distributing and / or storing fluids, said injection-molded part being chosen from connectors.

[0047] According to one embodiment, the monomaterial object of the invention may be a system for transporting, distributing and / or storing fluids, in particular for devices with thermal or electric engines, such as airplanes, drones, aircraft, trucks or motor vehicles.

[0048] It may notably be a system combining at least one tube and at least one connector, preferably a system combining at least one tube and two connectors, wherein said connectors allow said tubes to be assembled.

[0049] It may also be a system combining at least one tank and at least one connector, preferably a system combining at least one tank, at least one connector and at least one tube, wherein the connector allows the assembly of the tube and the tank.

[0050] According to one embodiment, the monolithic object of the present invention can be a system for transporting, distributing and / or storing fluids, notably for devices with thermal or electric engines, such as aircraft, drones, aircraft, trucks or motor vehicles, which combines at least one first element consisting of at least one extruded or extrusion-blow-molded part as defined according to the invention and at least one second element consisting of at least one injection-molded part as defined according to the invention, preferably at least two second elements consisting of at least one injection-molded part as defined according to the invention.

[0051] In particular, the monolithic object of the present invention can be a system for transporting, distributing and / or storing fluids, notably for a device having a thermal engine or an electric engine, such as an airplane, a drone, an aircraft, a truck or a motor vehicle, which combines at least N first elements consisting of at least one extruded or extrusion-blow-molded part as defined in accordance with the present invention and at least N+1 second elements consisting of at least one injection-molded part as defined in accordance with the present invention, where N is an integer greater than or equal to 1, in particular an integer greater than or equal to 2, for example an integer between 1 and 100. DETAILED DESCRIPTION

[0052] Long-chain homopolyamide and long-chain copolyamide regarding the composition of the first element and the second element

[0053] The nomenclature used to define polyamides is described in standard ISO 1874-1:2011 “Plastics—Polyamide (PA) molding and extrusion materials—Part 1: Designation”, in particular on page 3 (Tables 1 and 2), and is well known to those skilled in the art.

[0054] The long-chain homopolyamides and copolyamides (also referred to as “long-chain polyamides” for the purposes of the present invention) are polyamides having a C / N ratio (average number of carbon atoms per nitrogen atom) greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10.

[0055] In a first variant of the invention, the repeating unit is composed of at least one C4-C 36 Units obtained by polycondensation of amino acids (or aminocarboxylic acids),

[0056] Advantageously, the aminocarboxylic acid comprises 9 to 12 carbon atoms. Thus, it may be chosen from 9-aminononanoic acid (denoted as 9), 10-aminodecanoic acid (denoted as 10), 11-aminoundecanoic acid (denoted as 11) and 12-aminododecanoic acid (denoted as 12); advantageously, the aminocarboxylic acid is 11-aminoundecanoic acid.

[0057] In a second variant of the invention, the repeating unit is composed of at least one C4-C 36 Units obtained by polycondensation of lactams.

[0058] Advantageously, the lactam comprises 9 to 12 carbon atoms. Thus, it may be chosen from caprylic acid (denoted as 10), undecanoic acid (denoted as 11) and laurolactam or lauryllactam (denoted as 12); advantageously, the lactam is lauryllactam.

[0059] However, it is entirely conceivable to use mixtures of two or more aminocarboxylic acids, mixtures of two or more lactams, and mixtures of one, two or more aminocarboxylic acids with one, two or more lactams.

[0060] More particularly preferably, the repeat unit is derived from a single aminocarboxylic acid or a single lactam.

[0061] Repeating unit XY

[0062] In another variation, the repeating unit is unit XY.

[0063] The repeating units XY are units obtainable by polycondensation of at least one diamine selected from linear or branched aliphatic diamines, alicyclic diamines and semiaromatic aliphatic diamines, or mixtures thereof, and

[0064] At least one dicarboxylic acid selected from the group consisting of:

[0065] aliphatic diacids, cycloaliphatic diacids and aromatic diacids or mixtures thereof.

[0066] The molar ratio of diamine to dicarboxylic acid is preferably stoichiometric.

[0067] The diamine comprises from 4 to 36 carbon atoms, advantageously from 6 to 18 carbon atoms.

[0068] According to one embodiment, the diamine comprises 6 to 12 carbon atoms.

[0069] In the case where the diamine used to produce the repeating unit XY is an aliphatic diamine having a linear backbone, the linear backbone may include one or more methyl and / or ethyl substituents, where appropriate; in the latter configuration, it is referred to as a "branched aliphatic diamine". In the case where the backbone does not include any substituents, the aliphatic diamine is referred to as a "straight-chain aliphatic diamine".

[0070] Whether or not it comprises methyl and / or ethyl substituents on the main chain, the aliphatic diamine used to obtain the recurring unit XY comprises from 4 to 36 carbon atoms, advantageously from 6 to 18 carbon atoms, notably from 9 to 18 carbon atoms.

[0071] When the diamine is a linear aliphatic diamine, it corresponds to the formula H2N-(CH2)x-NH2 and can be chosen, for example, from butanediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decanediamine, undecanediamine, dodecanediamine, tridecanediamine, tetradecanediamine, hexadecanediamine, octadecanediamine and octadecenediamine. The linear aliphatic diamines just mentioned can all be biobased within the meaning of standard ASTM D6866.

[0072] When the diamine is a branched aliphatic diamine, it may notably be 2-methylpentanediamine, 2-methyl-1,8-octanediamine or (2,2,4- or 2,4,4-)trimethylenehexanediamine.

[0073] Cycloaliphatic diamines can be chosen, for example, from bis(3,5-dialkyl-4- aminocyclohexyl)methane, bis(3,5-dialkyl-4-aminocyclohexyl)ethane, bis(3,5-dialkyl-4- aminocyclohexyl)propane, bis(3,5-dialkyl-4-aminocyclohexyl)butane, bis(3-methyl-4- aminocyclohexyl)methane or 3'-dimethyl-4,4'-diaminodicyclohexylmethane, commonly known as "BMACM" or "MACM" (and denoted B hereafter), p-bis(aminocyclohexyl)methane, commonly known as "PACM", (and denoted P hereafter), isopropylidene di(cyclohexylamine), commonly known as "PACP", isophorone diamine (denoted IPD hereafter) and 2,6-bis(aminomethyl)norbornane, commonly known as "BAMN" or bis(aminomethyl)cyclohexane, commonly known as "BAC".

[0074] A non-exhaustive list of these cycloaliphatic diamines is given in the publication "Cycloaliphatic Amines" (Encyclopedia of Chemical Technology, Kirk-Othmer, 4thEdition (1992), pages 386-405).

[0075] When the diamine is a semi-aromatic aliphatic diamine, it is chosen, for example, from 1,3-xylylenediamine and 1,4-xylylenediamine.

[0076] The dicarboxylic acid comprises from 4 to 36 carbon atoms, advantageously from 6 to 18 carbon atoms and notably from 6 to 12 carbon atoms.

[0077] When the dicarboxylic acid is aliphatic, it can be chosen from linear or branched aliphatic dicarboxylic acids.

[0078] When the dicarboxylic acid is aliphatic and linear, it can be chosen from succinic acid (4), glutaric acid (5), adipic acid (6), pimelic acid (7), suberic acid (8), azelaic acid (9), sebacic acid (10), undecanedioic acid (11), dodecanedioic acid (12), tridecanedioic acid (13), tetradecanedioic acid (14), hexadecanedioic acid (16), octadecanedioic acid (18), octadecenoic acid (18), eicosanedioic acid (20), docosanedioic acid (22) and fatty acid dimers containing 36 carbons.

[0079] The fatty acid dimers mentioned above are dimer fatty acids obtained by oligomerization or polymerization of unsaturated monohydric fatty acids having long hydrocarbon chains, such as linoleic acid and oleic acid, as notably described in EP 0 471 566.

[0080] When the dicarboxylic acid is aromatic, it can be chosen from terephthalic acid (denoted T), isophthalic acid (denoted I) and naphthalenic acid (denoted N).

[0081] In one embodiment, the composition of the first element and the composition of the second element each consist of a single homopolyamide.

[0082] In another embodiment, the homopolyamides of the composition of the first element and of the second element are aliphatic semi-crystalline homopolyamides.

[0083] For the purposes of the present invention, the term "semi-crystalline homopolyamide" means a material that is generally solid at room temperature and softens during a temperature increase, in particular after passing through its glass transition temperature (Tg), and can melt sharply when passing through its "melting temperature" (Tm), and becomes solid again when the temperature decreases below its crystallization temperature.

[0084] For the purposes of the present invention, the semi-crystalline homopolyamide has a melting temperature (Tm) according to standard ISO 11357-3:2013 by DSC, and a crystallization enthalpy according to standard ISO 11357-3 of 2013 by DSC during the cooling step at a rate of 20 K / min greater than 25 J / g, preferably greater than 40 J / g.

[0085] Tg, Tc and Tm are determined according to standards 11357-2:2013 and 11357-3:2013 respectively by differential scanning calorimetry (DSC).

[0086] The number average molecular weight Mn of said semi-crystalline homopolyamide is preferably in the range extending from 10 000 to 85 000, notably from 10 000 to 60 000, preferably from 10 000 to 50 000, even more preferentially from 12 000 to 50 000.

[0087] In a first variant, the first and second compositions of the two elements are different.

[0088] The term "different" is understood to mean that the homopolyamide or copolyamide of the first composition is different from the homopolyamide or copolyamide of the second composition, or that the homopolyamide or copolyamide is identical, but in this case the compositions differ in terms of the ingredients other than the polyamide.

[0089] Advantageously, in the latter case, only one of the two compositions comprises a filler, the other not comprising any filler.

[0090] The term "filler" includes glass beads, fibres such as glass and carbon fibres, talc, carbon black and carbon nanotubes.

[0091] Preferably, the injection molded part comprises glass or carbon fibers or glass beads.

[0092] In one embodiment, the injection molded part comprises an electric current conducting filler, notably carbon black or carbon nanotubes (CNT).

[0093] In another embodiment, the extruded part and the injection molded part comprise an electric current conducting filler, notably carbon black or carbon nanotubes (CNT).

[0094] In a second variant, the first composition and the second composition comprise the same polyamide.

[0095] Advantageously, the first composition and the second composition comprise the same polyamide, in particular PA11, PA12, PA1010, PA1012, PA610 and PA612.

[0096] In a third variant, the single material object consists essentially of long chain aliphatic polyamides or a mixture of elements consisting of long chain aliphatic and semi-aromatic polyamides.

[0097] In a fourth variant, at least 10% by weight, in particular at least 30% by weight, of the units of the at least one homopolyamide or of the at least one copolyamide constituting the first composition and the second composition are identical.

[0098] In one embodiment of these four variants, the long chain homopolyamide is selected from:

[0099] Polyamide 11 (PA11), polyamide 12 (PA12), polyamide 1010 (PA1010), polyamide 1012 (PA1012), polyamide 1212 (PA1212), polyamide 612 (PA612), polyamide 610 (PA610) or mixtures thereof or copolyamides thereof, in particular PA11, PA12, PA610 and PA612.

[0100] With regard to copolyamides (PEBA) with amide units (Ba1) and polyether units (Ba2)

[0101] The following definitions apply both to the PEBA optionally excluded from the composition of the first element and the second element, and to the PEBA that can be present in the composition of the first element, the second element and the third element, as defined hereafter.

[0102] Polyether block amides (PEBA) are copolymers containing amide units (Ba1 ) corresponding to aliphatic repeating units selected from units obtained from at least one amino acid or units obtained from at least one lactam, or units X.Y obtained from the polycondensation of:

[0103] - at least one diamine, the diamine being preferably selected from linear or branched aliphatic diamines, or mixtures thereof, and

[0104] - at least one dicarboxylic acid, the diacid being preferably selected from:

[0105] linear or branched aliphatic diacids or mixtures thereof,

[0106] The diamine and the diacid comprise from 4 to 36 carbon atoms, advantageously from 6 to 18 carbon atoms;

[0107] The polyether units (Ba2) are notably obtained from at least one polyalkylene ether polyol, notably a polyalkylene ether diol.

[0108] PEBA is notably produced from the co-polycondensation of polyamide blocks with reactive ends with polyether blocks with reactive ends, for example, notably:

[0109] 1 ) polyamide blocks with diamine chain ends with polyoxyalkylene blocks with dicarboxylic acid chain ends.

[0110] 2) polyamide blocks with dicarboxylic acid chain ends with polyoxyalkylene blocks with diamine chain ends, obtained by cyanoethylation and hydrogenation of aliphatic a, w-dihydroxylated polyoxyalkylene blocks known as polyalkylene ether diols (polyether diols).

[0111] 3) polyamide blocks with dicarboxylic acid chain ends with polyether diols, the product obtained in this particular case being a polyether ester amide. The copolymers of the application are advantageously of this type.

[0112] Polyamide blocks with dicarboxylic acid chain ends are for example derived from the condensation of polyamide precursors in the presence of chain-limiting dicarboxylic acids.

[0113] Polyamide blocks with diamine chain ends are for example derived from the condensation of polyamide precursors in the presence of chain-limiting diamines.

[0114] Polymers with polyamide blocks and polyether blocks can also comprise units distributed randomly. These polymers can be prepared by simultaneous reaction of the precursors of the polyether and polyamide blocks.

[0115] For example, a polyether diol, a polyamide precursor and a chain-limiting diacid can be reacted. The obtained polymer essentially has polyamide blocks and polyether blocks of very variable length, but also various reagents that have reacted randomly, which are distributed randomly (statistically) along the polymer chain.

[0116] A polyether diamine, a polyamide precursor and a chain-limiting diacid can also be reacted. The obtained polymer essentially has polyamide blocks and polyether blocks of very variable length, but also various reagents that have reacted randomly, which are distributed randomly (statistically) along the polymer chain.

[0117] Amide unit (Ba1):

[0118] The amide unit (Ba1) corresponds to an aliphatic repeating unit as defined above.

[0119] Advantageously, the amide unit (Ba1) is selected from the group consisting of polyamide 11, polyamide 12, polyamide 610, polyamide 612, polyamide 1010, polyamide 910, polyamide 613, polyamide 514, polyamide 109, polyamide 1011, polyamide 516, polyamide 615, polyamide 913, polyamide 129, polyamide 1012, in particular polyamide 11.

[0120] More advantageously, the amide unit (Ba1) is selected from the group consisting of polyamide 11 and polyamide 12, in particular polyamide 11.

[0121] Polyether unit (Ba2):

[0122] The polyether unit is notably derived from at least one polyalkylene ether polyol, in other words, the polyether unit is formed from at least one polyalkylene ether polyol. In this embodiment, the term "at least one polyalkylene ether polyol" means that the polyether unit consists only of alcohol chain ends and thus cannot be a compound of the polyether diamine tri-block type.

[0123] Thus, the composition of the invention does not contain a polyether diamine tri-block.

[0124] Advantageously, the polyether unit (Ba2) is selected from the group consisting of polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene glycol (PO3G), polytetramethylene glycol (PTMG), and mixtures thereof or copolymers thereof, in particular PTMG.

[0125] The number average molecular weight (Mn) of the polyether block is advantageously between 200 and 4000 g / mol, preferably between 250 and 2500 g / mol, in particular between 300 and 1100 g / mol.

[0126] PEBA can be prepared by the following process, in which:

[0127] - in a first step, the polyamide block (Ba1) is prepared by polycondensation in the presence of a chain limiter chosen from dicarboxylic acids

[0128] lactams, or

[0129] amino acids, or

[0130] diamines and dicarboxylic acids; and, where appropriate, a comonomer chosen from lactams and a, w-amino carboxylic acids;

[0131] and then

[0132] - in a second step, the polyamide block (Ba1) obtained is reacted with a polyether block (Ba2) in the presence of a catalyst.

[0133] The two-step general process for preparing the inventive copolymer is known and is described, for example, in French patent FR 2 846 332 and European patent EP 1 482 011.

[0134] The reaction for forming the block (Ba1) is generally carried out at 180°C to 300°C, preferably 200°C to 290°C, and the pressure in the reactor is brought to be established at 5 bar to 30 bar and maintained for about 2 hours to 3 hours. The pressure is slowly reduced while the reactor is brought back to atmospheric pressure and then the excess water is removed by evaporation, for example, over 1 or 2 hours.

[0135] Once the polyamide with carboxylic acid end groups has been prepared, the polyether and the catalyst are then added. The polyether can be added in one or more portions, as can the catalyst. According to one advantageous form, the polyether is added first; the reaction of the OH end groups of the polyether and the COOH end groups of the polyamide begins with the formation of ester bonds and the elimination of water. As much water as possible is removed from the medium by distillation, then the catalyst is introduced to complete the linking of the polyamide block and the polyether block. This second step is carried out under stirring, preferably under vacuum of at least 15 mmHg (2000 Pa), at a temperature such that the reagents and the copolymer obtained are in molten form. For example, this temperature can be from 100°C to 400°C, and more commonly from 200°C to 300°C. The monitoring is carried out by measuring the torque exerted on the stirrer by the molten polymer or by measuring the electrical power consumed by the stirrer. The end of the reaction is determined by the target torque or power value.

[0136] During the synthesis, it is also possible to add one or more molecules used as antioxidants at the moment considered to be the most appropriate, for example Irganox ® 1010 or Irganox ® 245.

[0137] It is also possible to consider a PEBA preparation process which makes it possible to add all the monomers at the start, i.e. in a single step, to achieve the polycondensation of: - a diamine and a dicarboxylic acid; and, where appropriate, a comonomer chosen from lactams and a, w-amino carboxylic acids.

[0138] lactams, or

[0139] amino acids, or

[0140] diamines and dicarboxylic acids; and, if appropriate, other polyamide comonomers;

[0141] in the presence of a chain limiter selected from dicarboxylic acids;

[0142] in the presence of a (Ba2)(polyether) block;

[0143] in the presence of a catalyst for the flexibility between the (Ba2) block and the (Ba1) block.

[0144] Advantageously, the dicarboxylic acid is used as a chain limiter, introduced in stoichiometric excess relative to the diamine.

[0145] Advantageously, a derivative of a metal formed from titanium, zirconium and hafnium, or a strong acid such as phosphoric acid, hypophosphorous acid or boric acid is used as catalyst.

[0146] The polycondensation can be carried out at a temperature of 240 to 280°C.

[0147] In general, the known copolymers with ether and amide units consist of copolymers of semi-crystalline, linear, aliphatic polyamide blocks (such as Pebax® from Arkema).

[0148] In one embodiment, the copolyamide with amide units (Ba1) and polyether units (Ba2) has a density greater than or equal to 1, in particular greater than or equal to 1.01, notably greater than or equal to 1.02, as determined according to ISO 1183-3:1999.

[0149] In one embodiment, polyether amines are excluded from the polyether units (Ba2).

[0150] Regarding the single-material object

[0151] It consists of at least two elements: said at least one first element, defined here as (E1), and said at least one second element, defined here as (E2).

[0152] In a first variant, it consists of two said elements: E1 / E2.

[0153] The element E1 can be at least partially adhered to the element E2; in particular, E1 and E2 are at least partially adhered and in particular E1 and E2 are completely adhered, in particular by adhesive.

[0154] In a second variant, it consists of more than two elements: E1 / (E1)n / E2 / (E2)m, n and m being from 0 to 50, in particular from 3 to 50 elements, notably from 5 to 30 elements, in particular from 10 to 30 elements, and when n = 0, then m is greater than 0, and when m = 0, then n is greater than 0.

[0155] Needless to say, when two elements E1 or two elements E2 are side by side, they can be at least partially adhered together.

[0156] According to one embodiment, E1 and / or E2, preferably E1 and E2, can be intended for the transport, distribution and / or storage of fluids, notably for devices with thermal or electric motor, such as airplanes, drones, aircrafts, trucks or motor vehicles.

[0157] E1 can notably be chosen from tubes and tanks.

[0158] E2 can notably be a connector.

[0159] The present invention relates to a system protecting a combination of at least one tube or tank and at least one connector.

[0160] According to one embodiment, the single material object of the invention can be a system combining at least one tube and at least one connector, preferably a system combining at least two tubes and one connector, wherein said connector allows assembling said tubes.

[0161] According to one embodiment, the single material object of the invention can be a system combining at least two tubes and at least three connectors, preferably a system combining at least three tubes and four connectors, wherein said connectors allow assembling said tubes.

[0162] It can also be a system combining at least one tank and at least one connector, preferably a system combining at least one tank, at least one connector and at least one tube, wherein said connector allows assembling said tube and said tank.

[0163] The present invention also encompasses a system combining at least two tubes, preferably at least three tubes, at least three connectors, preferably at least four connectors, and optionally at least one tank.

[0164] In one embodiment, the homopolyamide or copolyamide of elements E1 and E2 comprises the same monomers, for example at least 10% by weight, advantageously at least 30%, of the same monomers relative to the total of the composition of said homopolyamide or copolyamide.

[0165] In another embodiment, said single material object as defined above is characterized in that at least 10 wt%, in particular at least 30 wt%, of the units of the at least one homopolyamide or the at least one copolyamide of the first composition and the second composition are identical; in particular, the units are PA11, PA12, PA1010, PA1012, PA610 and 612 units.

[0166] In yet another embodiment, said single material object as defined above is characterized in that the C / N difference between the at least one homopolyamide or the at least one copolyamide of the first composition and the at least one homopolyamide or the at least one copolyamide of the second composition is less than or equal to 3, in particular less than or equal to 2, notably less than or equal to 1.

[0167] In another embodiment, said single material object as defined above is characterized in that the at least one homopolyamide or the at least one copolyamide of the first composition and the at least one homopolyamide or the at least one copolyamide of the second composition comprise monomers having the same C / N.

[0168] The term "monomer" is to be understood as meaning a basic block, for example a combination of a lactam, an amino acid or a diamine with a dicarboxylic acid, as defined above.

[0169] In one embodiment, the monomers are identical in each composition.

[0170] In a third variant, said single material object can consist of more than two elements, i.e. at least three elements: said at least one first element defined herein as (E1) and said at least one second element defined herein as (E2) and said third element defined herein as E3.

[0171] Said single material object comprising at least a third element consists of a third composition comprising at least one homopolyamide or at least one copolyamide as defined above, or at least one copolyamide containing amide units (Bal) and polyether units (Ba2) or a mixture thereof.

[0172] The third element can be an extruded or extrusion blow molded part or an injection molded part.

[0173] In one embodiment, it consists of three elements: E1 / E2 / E3 or E1 / E3 / E2 or E3 / E1 / E2.

[0174] Element E1 can be at least partially adhered to element E2; in particular, E1 and E2 are at least partially adhered and notably E1 and E2 are completely adhered, in particular by an adhesive.

[0175] Element E2 can be at least partially adhered to element E3; in particular, E2 and E3 are at least partially adhered and notably E2 and E3 are completely adhered, in particular by an adhesive.

[0176] Element E1 can be at least partially adhered to element E3; in particular, E1 and E3 are at least partially adhered and notably E1 and E3 are completely adhered, in particular by an adhesive.

[0177] If at least one other element E1 and / or E2 and / or E3 is present in said single material object, it will not be outside the context of the present invention.

[0178] In a fourth variant, said single material object can consist of more than three elements, i.e. at least four elements: said at least one first element, defined here as (E1), said at least one second element, defined here as (E2), said third element, defined here as E3, and said fourth element, defined here as E4.

[0179] The third element can be an extruded or extrusion blow molded part or an injection molded part.

[0180] The fourth element can be an extruded or extrusion blow molded part or an injection molded part.

[0181] In one embodiment, it consists of four elements: E1 / E2 / E3 / E4 and all possible combinations of the arrangement of these four elements.

[0182] Each element can be at least partially adhered to the element behind it, in particular each element is at least partially adhered and notably each element is completely adhered.

[0183] Each element can be of non-recycled origin or at least partially of recycled origin.

[0184] The term "at least partially recycled" means that at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% of the recycled composition is present in said element, said recycled composition itself comprising at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90% of long chain homopolyamide or copolyamide.

[0185] In one embodiment, when the single material consists of three or more elements, said composition of the third element comprises at least one long chain homopolyamide or at least one long chain copolyamide.

[0186] In another embodiment, when the single material consists of three or more elements, said composition of the third element (E3) comprises at least one copolyamide bearing amide units (Ba1) and polyether units (Ba2).

[0187] In yet another embodiment, when the single material is composed of three or more elements, the composition of the third element comprises at least one long chain homopolyamide or a blend of at least one long chain copolyamide and at least one copolyamide bearing amide units (Bal) and polyether units (Ba2).

[0188] In another embodiment, the composition of the first element (El) comprises a single long chain homopolyamide or at least one long chain copolyamide.

[0189] In another embodiment, the composition of the second element (E2) comprises a single long chain homopolyamide or at least one long chain copolyamide.

[0190] In another embodiment, the composition of the third element (E3) (if present) comprises a single long chain homopolyamide or at least one long chain copolyamide.

[0191] In another embodiment, the composition of the third element (E3) (if present) comprises a single copolyamide bearing amide units (Bal) and polyether units (Ba2).

[0192] In another embodiment, the composition of the first element (El) comprises a single long chain homopolyamide or at least one long chain copolyamide and the composition of the second element (E2) comprises a single long chain homopolyamide or at least one long chain copolyamide.

[0193] In another embodiment, the composition of the first element (El) comprises a single long chain homopolyamide or at least one long chain copolyamide and the composition of the second element (E2) comprises a single long chain homopolyamide or at least one long chain copolyamide and the composition of the third element (E3) (if present) comprises a single long chain homopolyamide or at least one long chain copolyamide.

[0194] In another embodiment, the composition of the first element (El) comprises a single long chain homopolyamide or at least one long chain copolyamide and the composition of the second element (E2) comprises a single long chain homopolyamide or at least one long chain copolyamide and the composition of the third element (E3) (if present) comprises a single copolyamide bearing amide units (Bal) and polyether units (Ba2).

[0195] As mentioned above, the first element and the second element can be at least partially adhered to each other. When they are at least partially adhered to each other, the first element and the second element are adhered to each other by welding, dovetailing or by adhesion or clipping with a non-polyamide adhesive, the content of which ranges from 0.01 to 10% by weight, in particular from 0.1 to 4% by weight, relative to the total mass of the object, or the first element and the second element are introduced into each other.

[0196] The adhesive can be a polyurethane, acrylic, acrylonitrile, polyester, polyisoprene, polybutadiene or vinyl adhesive, preferably chosen from polyurethane, acrylic and polyester adhesives; advantageously, it corresponds to a polyurethane adhesive.

[0197] According to another aspect, the application relates to a method for manufacturing a single-material object as defined above, comprising steps involving:

[0198] - providing a first element consisting of a first composition comprising at least 30% by weight, notably at least 50%, in particular at least 70%, more particularly at least 90%, relative to the total weight of the first element, of at least one long-chain homopolyamide or at least one long-chain copolyamide, as defined above,

[0199] - providing a second element consisting of a second composition comprising at least 30% by weight, notably at least 50%, in particular at least 70%, more particularly at least 90%, relative to the total weight of the second element, of at least one long-chain homopolyamide or at least one long-chain copolyamide, as defined above,

[0200] The elements of the object are assembled, where appropriate by welding or adhesive, to form a finished or semi-finished object.

[0201] According to one embodiment, the method for manufacturing a single-material object as defined above can in particular comprise steps involving: assembling the elements of the object, where appropriate by means of welding, or by fir tree dowel joining, by clipping, or adhesion with a non-polyamide adhesive, to form a finished or semi-finished object.

[0202] In one embodiment, the method as defined above comprises a further step of providing, before assembly, a third element consisting of a third composition comprising at least 30% by weight, notably at least 50%, in particular at least 70%, more particularly at least 90%, relative to the total weight of the third element, of at least one long-chain homopolyamide or at least one long-chain copolyamide, as defined above, or at least one copolyamide bearing amide units (Bal) and polyether units (Ba2), or a mixture of the two.

[0203] In another embodiment, the method as defined above comprises a further step of providing, before assembly, a fourth element after the third element, the fourth element consisting of a fourth composition comprising at least 30%, notably at least 50%, in particular at least 70%, more particularly at least 90%, by weight relative to the total weight of the third element, of at least one long chain homopolyamide or at least one long chain copolyamide as defined above, or at least one copolyamide bearing amide units (Bal) and polyether units (Ba2), or a mixture of both.

[0204] In yet another embodiment, the method as defined above comprises a further step of providing, before assembly, an nth element consisting of an nth composition comprising at least 30%, notably at least 50%, in particular at least 70%, more particularly at least 90%, by weight relative to the total weight of the third element, of at least one long chain homopolyamide or at least one long chain copolyamide as defined above, or at least one copolyamide bearing amide units (Bal) and polyether units (Ba2), or a mixture of both, after the fourth element.

[0205] In another embodiment, the method as defined above comprises at least one further step after assembly.

[0206] After assembly, the further step can be a step of installation on a vehicle and of first commissioning by storing, distributing or transporting a fluid of need.

[0207] According to another aspect, the present application relates to a method for recycling an object as defined above, comprising steps involving:

[0208] (a) providing a used object,

[0209] (b) optionally separating elements of said object which are not recyclable in said method,

[0210] (c) optionally cleaning the used object from step (a) or (b),

[0211] (d) optionally, when cleaning of step (c) is performed, a first grinding of the used object of step (a) or (b), or of the used object of step (c), to obtain a first ground material,

[0212] (e) when cleaning of step (c) is not performed, optionally washing the first ground material,

[0213] (f) grinding the used object from step (a) and / or (b) and / or (c) and / or (d) and / or (e) to obtain a first ground material or a second ground material in case a first grinding in step (d) has been performed,

[0214] (g) optionally heating the ground material from step (f) until it is molten and pelletizing,

[0215] (h) optionally compounding and pelletizing,

[0216] (i) extruding or injection molding to manufacture an object.

[0217] The first and / or second grinding can be performed before or after cleaning.

[0218] Cleaning (or decontamination) is necessary in case of transporting, distributing or storing a liquid fluid, but is not necessary in case of transporting, distributing or storing a gas such as hydrogen or air.

[0219] Cleaning is performed by treating the structure with compressed air, in particular under pressure, or with hot water or steam.

[0220] Cleaning with compressed air allows removing non-polymeric particles such as dirt, sand or dust from the used object.

[0221] Cleaning with hot water or steam allows at least partially dissolving and removing water-soluble substances of the used object to obtain other constituents of the used object.

[0222] The temperature of the hot water or water steam is between 70°C and 150°C, in particular between 70°C and 120°C.

[0223] The hot water can have a pH between 1 and 12.

[0224] Compounding step (h) makes it possible to add impact modifiers and / or fillers and / or additives and / or plasticizers. This depends on the properties of the product after product analysis in step (f) or (g).

[0225] If step (h) is performed, the material obtained after said step (h) is in the form of pellets for the subsequent extrusion or injection molding.

[0226] The term "used object" means an object which is no longer new, which has already been used or which has already undergone a use, but in any case does not mean an industrial post-object which is to be recycled without having been used or without having been subjected to a use.

[0227] In another embodiment, the present application relates to the defined recycling method as above, further comprising the following steps:

[0228] (j) adding a new material to the abrasive material of the used object before or after step (f) or after step (g).

[0229] The term "new material" means another polymer, in particular another polyamide, in particular a polyamide having a C / N of less than 8, such as fillers and additives.

[0230] According to yet another aspect, the application relates to a recycled polyamide composition that can be obtained via the process as defined above.

[0231] According to yet another aspect, the application relates to a composition comprising, based on weight:

[0232] 15% to 100%, in particular 30% to 100%, advantageously 50% to 99% of a recycled polyamide obtained from an object as defined above,

[0233] 0% to 70% of a virgin polyamide selected from homopolyamides, in particular having a C / N ratio greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10, copolyamides, in particular having a C / N ratio greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10, and PEBA; the virgin polyamide is advantageously a homopolyamide, in particular having a C / N ratio greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10,

[0234] - 0% to 65%, in particular 0% to 35% of a virgin or recycled filler obtained from an object as defined above,

[0235] 0% to 30% of an impact modifier,

[0236] 0% to 5% of additives,

[0237] The recycled polyamide has functional groups resulting from oxidation selected from primary amide functions, nitriles, chain end methyl groups, olefins, formamides, imides, carboxylic acids and alcohols and mixtures thereof, in a molar ratio with respect to amide functions greater than the molar ratio of this functional group resulting from oxidation with respect to amide functions of the same polyamide constituting the virgin object that has never been used.

[0238] In particular, according to the application, the functional groups resulting from oxidation can be present in the recycled polyamide of the application in a molar ratio with respect to secondary amide functions at least 10% greater, for example at least 100% greater, for example at least 150% greater, for example at least 300% greater, than the molar ratio of the functional groups resulting from oxidation with respect to secondary amide functions of the same virgin polyamide elastomer.

[0239] When single material objects are used, new substances resulting from oxidation mechanisms can be seen in the polyamide constituting the pipe, the connector or the tank, notably amide functions and / or methylenes in alpha position of said amide functions, such as imide functions, carboxylic acids, primary amides and alcohols.

[0240] Said functions are considered as a result of UV radiation or heat, or as a result of a reaction with compounds with which the object is in contact (such as gasoline, sunscreen, lubricants, etc.).

[0241] Said functions can be detected by infrared or NMR spectroscopy.

[0242] Thus, an absorption band between 1700 and 1740 cm -1 corresponds to an imide, an absorption band between 1680 and 1720 cm -1 corresponds to the carbonyl of a carboxylic acid, an absorption band between 3580 and 3670 cm -1 corresponds to the alcohol function of a carboxylic acid.

[0243] An absorption band between 3580 and 3670 cm -1 corresponds to a free alcohol function.

[0244] The amide function is first of all characterized by a pair of absorption bands between 3100 and 3500 cm -1 and between 1560 and 1640 cm -1 corresponding to the NH groups of the amide, and secondly by an absorption band between 1650 and 1700 cm -1 corresponding to the carbonyl group of the amide.

[0245] In a first variant, the composition comprises by weight:

[0246] 50% to 70% of recycled polyamide from a single material object as defined above,

[0247] 30% to 50% of virgin polyamide chosen from homopolyamides, in particular long-chain homopolyamides, copolyamides, in particular long-chain copolyamides and PEBA; advantageously, the virgin polyamide is a homopolyamide,

[0248] 0 to 30% of impact modifier,

[0249] 0 to 5%, in particular 0.1% to 5%, of additives,

[0250] the sum of the components being equal to 100%.

[0251] In a second variant, the composition comprises by weight:

[0252] 30 to 50% of recycled polyamide from single material objects as defined above,

[0253] 0 to 65% of virgin polyamide selected from homopolyamides, in particular long chain homopolyamides, copolyamides, in particular long chain copolyamides and PEBA; advantageously, the virgin polyamide is a homopolyamide, in particular a long chain homopolyamide,

[0254] 0 to 30% of impact modifier,

[0255] 5 to 65% of filler, in particular 5 to 35% of filler,

[0256] 0 to 5%, in particular 0.1 to 5% of additives,

[0257] The sum of the components equals 100%.

[0258] In a third variant, the composition comprises by weight:

[0259] - 60 to 80% of recycled polyamide from single material objects as defined above,

[0260] - 0 to 20% of virgin polyamide selected from homopolyamides, in particular long chain homopolyamides, copolyamides, in particular long chain copolyamides and PEBA; advantageously, the virgin polyamide is a homopolyamide, in particular a long chain homopolyamide,

[0261] 0 to 30% of impact modifier,

[0262] 20 to 40% of filler,

[0263] 0 to 5%, in particular 0.1 to 5% of additives,

[0264] The sum of the components equals 100%.

[0265] In a fourth variant, the composition comprises by weight:

[0266] 40 to 60% of recycled polyamide from single material objects as defined above,

[0267] 0 to 20% of virgin polyamide selected from homopolyamides (in particular long chain homopolyamides), copolyamides (in particular long chain copolyamides) and PEBA; advantageously, the virgin polyamide is a homopolyamide, in particular a long chain homopolyamide,

[0268] 0 to 30% of impact modifier,

[0269] 40 to 60% of filler,

[0270] 0 to 5%, in particular 0.1 to 5% of additives,

[0271] The sum of the components equals 100%.

[0272] In one embodiment, in the composition of the other aspect and of its four variants, the term "comprising" is replaced by the term "consisting of".

[0273] The compositions of these four variants and of their embodiments are especially suitable for the compositions of the embodiments wherein the features of the single material object defined above are characterized by the fact that only one of the two compositions comprises a filler while the other one does not comprise any filler.

[0274] In one embodiment, said molar ratio of functional groups resulting from the oxidation reaction relative to the secondary amide functional groups is between 0.0001 and 0.3.

[0275] The concentration can be measured by proton NMR in dichloromethane-d2 with the addition of HFIP (hexafluoroisopropanol) to dissolve the polyamide.

[0276] In the first variant, said molar ratio of imide functional groups relative to the secondary amide functional groups is between 0.0005 and 0.02, notably between 0.001 and 0.08 and in particular between 0.005 and 0.05.

[0277] In one embodiment of this first variant, said molar ratio of imide functional groups relative to the secondary amide functional groups is between 1 / 1000 and 1 / 100, notably between 1 / 1000 and 1 / 300, in particular between 1 / 1000 and 1 / 500, more particularly between 1 / 1000 and 1 / 750.

[0278] In another embodiment of this first variant, said molar ratio of imide functional groups relative to the secondary amide functional groups is between 1 / 750 and 1 / 20, notably between 1 / 750 and 1 / 50, in particular between 1 / 750 and 1 / 100, more particularly between 1 / 750 and 1 / 300, in particular between 1 / 750 and 1 / 500.

[0279] In yet another embodiment of this first variant, said molar ratio of imide functional groups relative to the secondary amide functional groups ranges between 1 / 500 and 1 / 20, notably between 1 / 500 and 1 / 100, in particular between 1 / 750 and 1 / 300.

[0280] In yet another embodiment of this first variant, said molar ratio of imide functional groups relative to the secondary amide functional groups ranges between 1 / 300 and 1 / 20, in particular between 1 / 300 and 1 / 50, in particular between 1 / 300 and 1 / 100.

[0281] In a second variant, said molar ratio of carboxylic acid functions ranges from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.05.

[0282] In one embodiment of this second variant, said molar ratio of carboxylic acid functions to secondary amide functions ranges from 1 / 5000 to 1 / 20, in particular from 1 / 3000 to 1 / 25, notably from 1 / 3000 to 1 / 50, very advantageously from 1 / 500 to 1 / 15.

[0283] In one embodiment of this second variant, said molar ratio of carboxylic acid functions to secondary amide functions ranges from 1 / 1000 to 1 / 100, notably from 1 / 500 to 1 / 100, in particular from 1 / 400 to 1 / 100, more particularly from 1 / 300 to 1 / 100.

[0284] In a third variant, said molar ratio of alcohol functions ranges from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.05.

[0285] In one embodiment of this third variant, said molar ratio of alcohol functions to secondary amide functions ranges from 1 / 1000 to 1 / 20, advantageously from 1 / 1000 to 1 / 25 and very advantageously from 1 / 200 to 1 / 50.

[0286] In one embodiment of this third variant, said molar ratio of alcohol functions to secondary amide functions ranges from 1 / 1000 to 1 / 200, notably from 1 / 1000 to 1 / 300, in particular from 1 / 1000 to 1 / 400, more particularly from 1 / 1000 to 1 / 500.

[0287] In a fourth variant, said molar ratio of primary amide functions to secondary amide functions ranges from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.05.

[0288] In one embodiment of this fourth variant, said molar ratio of primary amide functions to secondary amide functions ranges from 1 / 500 to 1 / 15, in particular from 1 / 400 to 1 / 15, notably from 1 / 300 to 1 / 15, more particularly from 1 / 200 to 1 / 15, notably from 1 / 100 to 1 / 15.

[0289] In a fifth variant, said molar ratio of nitrile functions to secondary amide functions ranges from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.05.

[0290] In a sixth variant, said molar ratio of chain end methyl functions relative to secondary amide functions ranges from 0.0005 to 0.02, notably 0.001 to 0.08, in particular 0.005 to 0.05.

[0291] Needless to say, depending on the single material objects used and the exposure they have been subjected to, there can be one or more functions resulting from oxidation reactions.

[0292] The composition advantageously also comprises residues of a stabilizer selected from phenols, quinones, stilbenes and phosphites.

[0293] The recycled polyamide advantageously comprises alkyl chain ends having a carbon number (between 1 and 18) greater than that of the original PA. Advantageously, the alkyl chain end content is between 1 ppm and 0.5%.

[0294] According to another aspect, the application relates to the use of a composition as defined above for the manufacture of an object, in particular a single material object.

[0295] Said single material object thus manufactured from a used single material object can itself be recycled according to the method of the application at least once, in particular between 1 and 10 times.

[0296] According to another aspect, the application relates to the use of a composition as defined above for the manufacture of an object, in particular a single material object.

[0297] According to another aspect, the application relates to the use of a single material object as defined above for the manufacture of a system for transporting, distributing and / or storing a fluid, notably for a device with a thermal or electric engine, such as an airplane, drone, aircraft, truck or motor vehicle.

[0298] In one embodiment, said fluid is selected from hydrogen and a coolant.

[0299] Example

[0300] The examples in Tables 1, 2 and 3 below were ground and then granulated using a twin-screw extruder.

[0301] [Table 1]

[0302]

[0303] [Table 2]

[0304]

[0305] [Table 3]

[0306]

[0307] Injection molded parts 1, 2, 3, 4, 5 and 6 are connectors.

[0308] Extruded parts 1, 2, 3, 4, 5 and 6 are single layer pipes for the transport of coolant.

[0309] PA 11 BESNO TL: Arkema

[0310] PA 11 KNO: Arkema

[0311] Orevac IM 800: SK functional polymer

[0312] Stabilizers: 0.5% Lowinox 44B25 (SI group) and 0.2% Irgafos 168 (BASF)

[0313] HDPE: High Density Polyethylene 5502: Total Energie

[0314] PA 6 Ultramid B27: BASF

[0315] Glass fibers: CS 7928: Lanxess Deutschland GMBH

[0316] Objects CE1, IE1, CE2, IE2, CE3 and IE3 were ground to a size of less than 30 mm and then compounded in an 18 mm twin-screw extruder at a flow rate of 5 kg / h and a temperature of 280°C in order to obtain granules for the evaluation of the properties obtained during the second life of the material.

[0317] The granules thus obtained were then injection molded using a Battenfeld BA800 CDC press in order to manufacture ISO 527 1A test specimens and ISO 179 impact bars. The following parameters were applied during injection molding:

[0318] - Cylinder temperature: 270°C.

[0319] - Nozzle temperature: 290°C.

[0320] - Mold temperature: 40°C.

[0321] - Cycle time: 60 seconds.

[0322] The impact strength was determined on five V-notched bars measuring 80 mm x 10 mm x 4 mm on dry samples at a temperature of 30°C ± 2°C according to the standard ISO 179-1:2010 / 1eA (Charpy impact).

[0323] The elongation at break is measured on test specimens corresponding to the standard ISO 527 1 A.

[0324] The results are presented in Tables 4 and 5.

[0325] [Table 4]

[0326]

[0327] [Table 5]

[0328]

[0329] The above examples show that the properties obtained after recycling the objects according to the application are better, so that the objects can be recycled to make new high-performance objects.

[0330] Furthermore, the evaluation of the cold impact strength shows that the objects of the application have better performance after recycling.

[0331] Examples CE1 and IE1 comprise an impact modifier (Orevac IM800) and are particularly suitable for applications requiring impact strength, in particular with respect to cold.

[0332] Examples CE2 and IE2 comprise glass fibers and are particularly suitable when resistance to pressure is required.

[0333] Examples CE3 and IE3 allow a compromise to be reached between impact strength, elongation at break and a rather high tensile modulus (compared to CE1 and IE1).

[0334] In all three cases, the composition according to the application makes it possible to achieve better performance of the objects and therefore greater durability.

Claims

1. A monomaterial object, notably a recyclable monomaterial object, consisting essentially of long-chain polyamide, comprising at least two elements: at least one first element, at least one first element consisting of at least one extruded or extrusion-blow-molded part intended for the transport, distribution and / or storage of fluids, in particular chosen from pipes and tanks, comprising at least one layer consisting of a first composition comprising at least 30%, notably at least 50%, in particular at least 70%, more in particular at least 90% by weight of at least one homopolyamide or at least one copolyamide relative to the total weight of the first element, said at least one homopolyamide or at least one copolyamide of the first composition having a C / N ratio greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10, The at least one homopolyamide and the at least one copolyamide independently represent repeating units selected from the group consisting of at least one C4-C 36 The unit obtained by polycondensation of amino acids, composed of at least one C4-C 36 Units obtained by polycondensation of lactams and XY units obtained by polycondensation of: at least one diamine selected from linear or branched aliphatic diamines, alicyclic diamines and semiaromatic aliphatic diamines, or mixtures thereof, and At least one dicarboxylic acid selected from the group consisting of: aliphatic diacids, cycloaliphatic diacids and aromatic diacids or mixtures thereof, said diamine and said diacid contain from 4 to 36 carbon atoms, advantageously from 6 to 18 carbon atoms, at least one second element consisting of at least one injection-molded part consisting of a second composition comprising at least 30%, notably at least 50%, in particular at least 70%, more particularly at least 90% by weight of at least one homopolyamide or at least one copolyamide as defined above for the first composition, relative to the total weight of the second element, And the first element and the second element can be at least partially adhered to each other.

2. The single-material object according to claim 1, characterized in that The single-material object is selected from the group consisting of a motor vehicle component, a truck component, an aircraft component, and a drone component.

3. The single-material object according to claim 1 or 2, characterized in that The first composition and the second composition are different.

4. The single-material object according to claim 1, wherein Only one of the two compositions contained a filler, the other did not contain any filler.

5. The single-material object according to claim 1, characterized in that The single-material object consists essentially of aliphatic long-chain polyamide or a mixture of elements consisting of aliphatic and semiaromatic long-chain polyamide.

6. The monolithic object according to claim 1, wherein: The first composition and the second composition comprise the same polyamide, in particular PA11, PA12, PA1010, PA1012, PA610 or PA612.

7. The single-material object according to claim 1, characterized in that At least 10% by weight, in particular at least 30% by weight, of the units constituting the at least one homopolyamide or the at least one copolyamide of the first and second compositions are identical; in particular, the units are PA11, PA12, PA1010, PA1012, PA610 and PA612 units.

8. The monolithic object according to claim 1, characterized in that The C / N difference between the at least one homopolyamide or the at least one copolyamide of the first composition and the at least one homopolyamide or the at least one copolyamide of the second composition is less than or equal to 3, in particular less than or equal to 2, in particular less than or equal to 1.

9. The monolithic object according to claim 1, wherein: The at least one homopolyamide or the at least one copolyamide of the first composition and the at least one homopolyamide or the at least one copolyamide of the second composition comprise monomers having the same C / N ratio.

10. The single-material object according to claim 9, characterized in that The monomers were the same in each composition.

11. The monolithic object according to claim 1, wherein: The first element and the second element are adhered to each other by welding, fir-tree dovetail joints, or bonding or clamping with the aid of a non-polyamide adhesive, wherein the content of the non-polyamide adhesive ranges from 0.01% to 10% by weight, in particular from 0.1% to 4% by weight, relative to the total mass of the object, or the first element and the second element are introduced into each other.

12. The monolithic object according to claim 1, characterized in that The monomaterial object comprises at least one third element consisting of a third composition comprising at least one homopolyamide or at least one copolyamide as defined in claim 1, or at least one copolyamide containing amide units (Ba1) and polyether units (Ba2), or a mixture thereof.

13. The single-material object according to claim 12, characterized in that The monomaterial object comprises at most 50 elements, in particular 3 to 50 elements, in particular 5 to 30 elements, in particular 10 to 30 elements.

14. A method for producing a mono-material object according to any one of claims 1 to 13, comprising the steps of: providing a first element consisting of a first composition comprising at least 30%, notably at least 50%, in particular at least 70%, more particularly at least 90% by weight of at least one long-chain homopolyamide or at least one long-chain copolyamide as defined above, relative to the total weight of the first element, providing a second element consisting of a second composition comprising at least 30%, notably at least 50%, in particular at least 70%, more particularly at least 90% by weight of at least one long-chain homopolyamide or at least one long-chain copolyamide as defined above, relative to the total weight of the second element, The elements of the object are assembled, where appropriate, by means of welding or adhesives, to form a finished or semi-finished object.

15. A method for recycling an object as defined in any one of claims 1 to 13, comprising the steps of: (a) provide the used object, (b) optionally separating elements of the object that are not recyclable in the process, (c) optionally cleaning the used object from step (a) or (b), (d) optionally, while performing the cleaning of step (c), performing a first grinding of the used object of step (a) or (b), or the used object of step (c), to obtain a first ground material, (e) when the cleaning of step (c) is not performed, optionally washing the first abrasive material, (f) grinding the used objects from step (a) and / or (b) and / or (c) and / or (d) and / or (e) to obtain a first ground material or, in case the first grinding in step (d) has been carried out, a second ground material, (g) optionally heating the ground material from step (f) until it is molten and granulating, (h) optionally compounding and granulating, (i) Extrusion or injection molding to make objects.

16. The recycling method according to claim 15, further comprising the steps of: (j) adding new material to the ground material of the used object before or after step (f) or after step (g).

17. A recycled polyamide composition obtainable via the process according to claims 15 to 16.

18. A composition comprising, by weight: 15% to 100%, in particular 30% to 100%, advantageously 50% to 99% of recycled polyamide obtained from the object defined in any one of claims 1 to 13, 0 to 70% of a virgin polyamide chosen from homopolyamides, in particular having a C / N ratio greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10, copolyamides and PEBAs; the virgin polyamide is advantageously a homopolyamide, in particular having a C / N ratio greater than or equal to 8, in particular greater than or equal to 9, notably greater than or equal to 10, 0 to 65%, advantageously 0 to 35%, of virgin or recycled filler obtained from a body as defined in any one of claims 1 to 8, 0 to 30% impact modifier, 0 to 5% additives, The recycled polyamide has functional groups derived from oxidation selected from the group consisting of primary amide functional groups, nitriles, chain-terminal methyl groups, olefins, formamides, imides, carboxylic acids and alcohols, and mixtures thereof, wherein the molar ratio of the functional groups derived from oxidation to the amide functional groups is greater than the molar ratio of the functional groups derived from oxidation to the amide functional groups of the same polyamide constituting an virgin object that has never been used.

19. The composition according to claim 18, characterized in that The molar ratio of the functional groups generated by the oxidation reaction relative to the secondary amide functional groups is 0.0001 to 0.

3.

20. The composition according to any one of claims 18 and 19, characterized in that Said molar ratio of imide functional groups is from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.

05.

21. The composition according to any one of claims 18 to 20, characterized in that Said molar ratio of carboxylic acid functional groups relative to secondary amide functional groups is from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.

05.

22. The composition according to any one of claims 18 to 21, characterized in that Said molar ratio of alcohol functions relative to secondary amide functions is from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.

05.

23. The composition according to any one of claims 18 to 22, characterized in that Said molar ratio of primary amide functional groups relative to secondary amide functional groups is from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.

05.

24. The composition according to any one of claims 18 to 23, characterized in that Said molar ratio of nitrile functional groups relative to secondary amide functional groups is from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.

05.

25. The composition according to any one of claims 18 to 24, characterized in that Said molar ratio of chain end methyl functions relative to secondary amide functions is from 0.0005 to 0.02, notably from 0.001 to 0.08, in particular from 0.005 to 0.

05.

26. Use of the composition according to any one of claims 17 to 25 for producing an object, in particular a monomaterial object.

27. Use of a single-material object as defined in any one of claims 1 to 13 for producing a system for transporting, distributing or storing fluids, notably for devices with a thermal or electric engine such as airplanes, drones, aircraft, trucks or motor vehicles.

28. Use of a monomaterial object according to claim 27, characterized in that The fluid is selected from hydrogen gas and a cooling liquid.

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