Recyclable elastic filament based on a copolymer of polyamide and polyether blocks

Abstract

The invention relates to an elastic filament comprising a copolymer of polyamide blocks and polyether blocks, - the polyamide blocks being chosen from PA 11, PA 12, PA1010, PA 1012, PA 1014, their copolymer and their mixture, - the polyether blocks being blocks derived from polytetramethylene glycol with an average molecular mass by weight between 500 and 3000 g / mol, - the enthalpy of fusion of the copolymer being between 15 and 50 J / g.

Description

Title of the invention: Recyclable elastic filament based on a copolymer of polyamide and polyether blocks

[0001] The present invention relates to a recyclable elastic filament based on a block copolymer of polyamide and polyether. The invention also relates to a fiber comprising at least one filament according to the invention, a textile material, a method for manufacturing the filament, a use of the fiber for manufacturing woven and non-woven materials, as well as on the textile material. Finally, the invention relates to a method for recycling the fibers according to the invention.

[0002] The use of synthetic textile fibers based on polyamide has been known for many years. These textiles include fiber mats (dressings, filters, felt), wicks (dressings), yarns (sewing thread, knitting yarn, weaving yarn), knits (straight, circular, fully fashioned, or shaped), fabrics (traditional fabric, Jacquard fabric, multi-ply fabric, double-sided fabric, multi-axial fabric, 2.5D fabric, 3D fabric), and many others. Innovations in this field appear regularly, such as for sportswear that allows for easier sweat wicking. Furthermore, since the 1960s, elastic textiles based on polyurethane have been developed. These synthetic fibers are known as elastane. This name is a contraction of elastic and polyurethane.These fibers are notably used in the field of sports, or in elastic fabrics, which can contain between 2 and 10% elastane in their composition. For sports tights, elastic bands or socks, the elastane content in the garment can reach up to 30% by weight.

[0003] These fibers have particularly interesting characteristics, such as an elongation of up to 600%, an elastic recovery of more than 90%, and a very low weight.

[0004] However, in view of current environmental considerations, the recyclability of materials is a major issue, and in particular of textile materials, which are produced in considerable quantities.

[0005] It turns out that elastanes are cross-linked polyurethanes. This cross-linking prevents the recycling of these fibers because, after cross-linking, these fibers are no longer heat-fusible.

[0006] Alternatives exist such as polyesters or elastolefins, but their elasticity is limited and these materials are not compatible with polyamides.

[0007] Therefore, recyclable elastic filaments are sought, exhibiting a Improved elasticity and compatibility with other textile fibers, such as polyamides, are also sought. Textile materials that allow for a simple recycling process, requiring only a few steps, are also desired. Another objective is to obtain a valuable recycled product, meaning one that leads to a high-performing product either for the same application or for other industrial applications.

[0008] By "polymer compatible with other textile fibres", it is understood in the context of the present invention that, during recycling, and in particular after the melting stage, the molten material is homogeneous.

[0009] It has been discovered that the filaments according to the invention meet the existing need.

[0010] Brief description of the invention

[0011] Thus, the present invention relates to an elastic filament comprising a copolymer with polyamide blocks and polyether blocks, -the polyamide blocks being chosen from PA 11, PA 12, PA1010, PA 1012, PA 1014, their copolymer and their mixture, -polyether blocks being blocks derived from polytetramethylene glycol with a number-average molar mass between 500 and 3000 g / mol, -the enthalpy of fusion of the copolymer being between 15 and 50 J / g.

[0012] The invention relates to a fiber manufactured from the filament as defined below or the container.

[0013] The invention relates to a textile material made from the fiber as defined below.

[0014] The invention also relates to a method for manufacturing the fiber.

[0015] The invention also relates to a use of the filament to manufacture textile materials.

[0016] Finally, the invention relates to a method for recycling filament, fibers or textile material according to the invention.

[0017] The filament according to the invention has the advantage of being recyclable. Its rheological stability allows it to be easily remelted and reused to manufacture granules, potentially leading to new objects and new applications, such as new fibers. The properties of the fiber according to the invention, after repeated remelting, are very close to, or even identical to, those of the fiber melted for the first time. Detailed description of the invention

[0018] Other features, aspects, objects and advantages of the present invention will become even clearer upon reading the following description.

[0019] In this description of the invention, including in the examples below: - The term "thermoplastic polymer" refers to a polymer having the property of softening when heated sufficiently, and which, upon cooling, becomes hard again. The term "thermoplastic elastomer" refers to a polymer comprising both flexible and rigid segments, for example, in the form of a block copolymer, in which the rigid segments disappear as the temperature increases. Alternatively, it can refer to mixtures combining a flexible elastomer phase, crosslinked or not, dispersed within a continuous rigid thermoplastic phase. These mixtures may include, in particular, blends of a thermoplastic polymer with an elastomer. The term "copolymer" refers to a polymer resulting from the copolymerization of at least two chemically different types of monomers, called comonomers. A copolymer is therefore composed of at least two different repeating units. It can also be composed of three or more repeating units. More specifically, the terms "sequenced copolymer" or "block copolymer" refer to copolymers in the aforementioned sense, in which at least two distinct monomer blocks are covalently linked. The length of the blocks can vary. Preferably, the blocks are composed of 1 to 1000, preferably 1 to 100, and in particular 1 to 50 repeating units. The link between the two monomer blocks may sometimes require an intermediate non-repeating unit called a junction block. - The term "melting temperature" means the temperature at which a partially crystalline polymer transitions to a viscous liquid state, as measured during the first heating (Tfl) by differential scanning calorimetry (DSC) according to standard NF EN ISO 11 357-3 using a heating rate of 20°C / min. - The term "enthalpy of fusion" refers to the heat consumed during the solid / liquid transition of the thermoplastic elastomer, as measured by differential scanning calorimetry, according to ISO 11357-3: 1999.

[0020] The nomenclature used to define polyamides is described in ISO 1874-1:2011 "Plastics - Polyamide (PA) materials for molding and extrusion - Part 1: Designation", in particular on page 3 (tables 1 and 2) and is well known to those skilled in the art.

[0021] It is further specified that the expressions "between... and..." and "from... to..." used in this description should be understood as including each of the limits mentioned.

[0022] The word “polyamide” covers both homopolyamides and copolyamides.

[0023] In this description of the invention, the following definitions apply:

[0024] - by "textile material" or "textile" means any material made from fibers or filaments as well as any material forming a porous membrane characterized by a length / thickness ratio of at least 300;

[0025] - by "fiber" means any synthetic or natural material, characterized by a ratio length / diameter of at least 300;

[0026] - by "filament", any fiber of infinite length.

[0027] The invention is now described in more detail and in a non-limiting manner in the following description.

[0028] The filament

[0029] The invention relates to an elastic filament comprising a copolymer with polyamide blocks and polyether blocks, -the polyamide blocks being chosen from PA 11, PA 12, PA1010, PA 1012, PA 1014, their copolymer and their mixture, -polyether blocks being blocks derived from polytetramethylene glycol with a number-average molar mass between 500 and 3000 g / mol, -the enthalpy of fusion of the copolymer being between 15 and 50 J / g.

[0030] Generally, the number-average molar mass of polyethers is disclosed in the technical data sheets provided by the suppliers, polyether being a commercially available product.

[0031] If necessary, the number-average molar mass Mn of the polyether blocks included in the filament according to the invention can be measured before copolymerization by size exclusion chromatography (SEC) according to ISO 16014-1:2012 using hexafluoroisopropanol (HFIP) as the eluent, and for 24 h at room temperature at a concentration of 1 g / L before the molar mass is measured by the refractive index.

[0032] The polyamide-polyether block copolymer, also called block amide copolyether, or abbreviated as "PEBA", results from the polycondensation of reactive-end polyamide blocks with reactive-end polyether blocks, such as, among others: 1) polyamide blocks with diamine chain ends with polyoxyalkylene blocks with dicarboxylic chain ends; 2) polyamide blocks with dicarboxylic chain ends with polyoxyalkylene blocks with diamine chain ends, obtained by cyanoethylation and hydrogenation of aliphatic alpha-omega dihydroxylated polyoxyalkylene blocks called poly-etherdiols; 3) polyamide blocks with dicarboxylic chain ends with polyetherdiols, the products obtained being, in this particular case, polyetheresteramides.

[0033] Polyamide blocks with dicarboxylic chain ends are obtained, for example, from the condensation of polyamide precursors in the presence of a chain-limiting dicarboxylic acid. Polyamide blocks with diamine chain ends are obtained, for example, from the condensation of polyamide precursors in the presence of a chain-limiting diamine.

[0034] Rigid polyamide block

[0035] The polyamide block and polyether block copolymer included in the filament according to the invention comprises at least one polyamide block selected from PA 11, PA 12, PA 1010, PA 1012, PA 1014, their copolymer and their mixture.

[0036] In other words, the polyamide block contained in the copolymer according to the invention is obtained by polycondensation of at least one linear aliphatic motif selected from undecanolactam, lauryllactam, amino-11-undecanoic acid (noted 11), amino-12-dodecanoic acid (noted 12), the motif obtained by polycondensation of decanediamine and sebacic acid (noted 1010), the motif obtained by polycondensation of decanediamine and dodecanedioic acid (noted 1012), and the motif obtained by polycondensation of decanediamine and tetradecanedioic acid (noted 1014). Preferably, the PA blocks contained in the copolymer according to the invention are PAU and PA 12, their copolymer, and their mixture.

[0037] According to one embodiment of the invention, the number-average molar mass of the rigid polyamide blocks is between 500 and 4000 g / mol and preferably between 600 and 2000 g / mol.

[0038] The number-average molar mass can be determined from the quantities of reactants introduced into the reaction medium during the synthesis of the polyamide blocks. This mass can then be verified on the final copolymer by NMR.

[0039] Flexible polyether block

[0040] The polyamide-polyether block copolymer included in the filament according to the invention comprises at least one block consisting of tetramethylene glycol motifs, also called polytetrahydrofuran and hereinafter referred to as PTMG. The tetramethylene glycol block has OH chain ends. It is also possible to modify these ends into amine groups.

[0041] The flexible polyether blocks may comprise PTMG blocks with NH2 chain ends, such blocks being obtained by cyanoacetylation of the PTMG blocks. More particularly, Jeffamines may be used (For example Jeffamine® D400, D2000, ED 2003, XTJ 542, commercial products of Huntsman, also described in patent documents JP2004346274, JP2004352794 and EP1482011).

[0042] The flexible polyether blocks may also include PTMG blocks with PPG-NH2 chain ends. In other words, the PTMG chain terminates with a propylene glycol motif, followed by an amine function.

[0043] The average number-rate molar mass of flexible PTMG blocks is between 500 and 3,000 g / mol, preferably between 650 and 2500, and more particularly between 1000 and 2000 g / mol. block copolymer

[0044] By elastic, we mean according to the present invention the ability of the filament or fiber to return to at least 80% of the initial length LO after release of the stress applied to this same filament or fiber, under the conditions of the following test.

[0045] The elasticity measurement is performed using a dynamometer with a maximum capacity of 10 N. The initial filament length is L0 = 100 mm and the deformation rate is 100 mm / min. These conditions allow the yield stress of the filaments to be determined. A preload of 0.02 N is applied at the start of the test to limit the variation in the toe length. A 1-minute pause is applied before each elongation or relaxation. The values ​​are based on a minimum of 5 test specimens or filaments.

[0046] The copolymer included in the filament according to the invention has an enthalpy of fusion of between 15 and 50 J / g, measured according to the standard as defined above, preferably between 15 and 40 J / g, and more particularly between 20 and 40 J / g.

[0047] The number-average molar mass of the polyamide blocks and polyether blocks can be determined after copolymerization of the blocks by NMR. Measurement protocols are detailed in the article "Synthesis and characterization of poly(copolyethers-block-polyamides) - II. Characterization and properties of the multiblock copolymers", Maréchal et al., Polymer, Volume 41, 2000, 3561-3580.

[0048] Advantageously, in the copolymer included in the filament according to the invention, the weight ratio of the polyamide blocks to the polyether blocks is between 0.3 and 3, preferably between 0.3 and 2, and more particularly between 0.5 and 2.

[0049] The copolymer included in the filament according to the invention preferably has a hardness measured according to standard 7619-1 between 30 and 55 ShD, preferably between 30 and 40 ShD.

[0050] Preferably, the filament according to the invention has a melting temperature less than or equal to 150°C, and preferably less than or equal to 130°C; and / or a volume flow index MVR of 2 to 200 cm3 / 10 min, and preferably 5 to 70 cm3 / 10 min.

[0051] The elastic filament according to the invention can be made of the copolymer as defined above.

[0052] According to another embodiment, the filament according to the invention may comprise at least one other thermoplastic material.

[0053] The thermoplastic material can be chosen from polyamides, polyethylene terephthalates, polypropylenes, polyethylenes, PEBA copolymers other than that according to the invention.

[0054] According to an embodiment of the invention, the filament can be manufactured by co-extrusion. This co-extruded filament can be made of two or three different materials.

[0055] According to one embodiment, the filament is co-extruded with another thermoplastic material chosen from polyamides, polyethylene terephthalates, polypropylenes, polyethylenes, PEBA copolymers other than that defined according to the invention.

[0056] The co-extruded filament can be of different structures: core / skin, island in sea or trilobed.

[0057] According to a preferred embodiment of the invention, the filament is co-extruded, it comprises the polyamide and polyether block copolymer as defined above and polyamide, the core of the filament being PEBA according to the invention and the skin of the filament being polyamide.

[0058] These co-extruded filaments can be co-mixed to make fibers.

[0059] Process for preparing the copolymer

[0060] The block copolymer included in the filament according to the invention can be prepared in a manner known to those skilled in the art, for example, by mixing the polyamide and PTMG blocks in a molten state.

[0061] Alternatively, the block copolymer can be prepared by mixing in a molten state the monomers constituting the polyamide and PTMG blocks.

[0062] The process for synthesizing the copolymer defined above may include the following steps: - mixing and reacting at least one PA block with at least one PTMG block, - recovery of said copolymer.

[0063] According to a preferred embodiment, the process according to the invention comprises the following steps: - loading a reactor with a mixture comprising at least one PA block, at least one PTMG block, - heating to a setpoint temperature within the range of 180 to 340°C, preferably 200 to 300°C, preferably 220 to 270°C, - agitation and sweeping under inert gas, - vacuum sealing at a pressure below 100 mbar, preferably below 50 mbar, preferably below 10 mbar, - addition of a catalyst, - stop when a torque of at least 5 N.cm, preferably at least 10 N.cm, preferably at least 20 N.cm, is reached. Filament manufacturing process

[0064] All melt spinning processes can be used, in particular by passing the copolymer defined above through dies comprising one or more orifices. For the manufacture of multifilament yarns or fibers, examples include spinning or spinning-drawing or spinning-drawing-texturizing processes, whether integrated or not, regardless of the Spinning speed. Yarns can be produced by high-speed spinning, at a spinning speed of 3000 m / min or higher, preferably 4000 m / min or higher. Such processes are often referred to as POY (partially oriented yam), FOY (fully oriented yam), FEI (integrated spinning-drawing), and HOY (highly oriented yam with a speed exceeding 5500 m / min). These yarns or fibers can also be textured, depending on their intended use. Yarns or fibers obtained by these processes are particularly suitable for producing woven or knitted textile surfaces. According to the invention, the copolymer defined above can be used to manufacture monofilament yarns or fibers, multifilament yarns or fibers, continuous fibers (in spools), or staple fibers (chopped). Discontinuous filaments are particularly well suited for blending with natural fibers.

[0065] For individual filaments or monofilaments, the counts can range from 1 dtex to 1000 dtex / filament, with high counts being particularly well-suited for industrial applications. Multifilament yarns or fibers preferably have a count of 15 dtex / filament or less. For fiber manufacturing, the filaments can, for example, be joined into rovings or webs, either directly after spinning or in subsequent spinning, drawn, textured or curled, and cut.

[0066] Typically, the polymer is spun in the molten state, then stretched between 2 and 10 times its length, preferably 5 times its length at room temperature, then the yarn is shrunk at room temperature and preferably stabilized at 100°C. The fiber

[0067] The invention also relates to a fiber comprising at least one filament as defined above.

[0068] The fibre or fibres according to the invention may comprise one or more synthetic filaments different from that defined above and / or may comprise one or more natural filaments.

[0069] The fibers according to the invention can be used for the manufacture of nonwovens or fiber yarns. The filament or fiber can also be used for the manufacture of flocks. The filaments and fibers of the invention can undergo various treatments such as, for example, continuous or repeated single-stage drawing, sizing, oiling, interlacing, texturizing, curling, drawing, heat treatment for fixing or relaxing, twisting, pliing, and / or dyeing.

[0070] For dyeing, bath dyeing and jet dyeing processes are particularly noteworthy. Preferred dyes are acid dyes, metallic or non-metallic. Mass dyeing is also possible, through the use of a masterbatch.

[0071] In one embodiment, the toughness of the fiber according to the invention is 0.3 cN / dTex, in particular greater than 0.5 cN / dTex, in particular it is between 0.5 and 10 cN / dTex.

[0072] The fiber according to the invention can be co-mixed with at least one fiber in a thermoplastic matrix different from the PEBA copolymer defined above.

[0073] The thermoplastic material can be chosen from polyamides, polyethylene terephthalates, polypropylenes, polyethylenes, PEBA copolymers other than that according to the invention.

[0074] The fiber according to the invention can be continuous or discontinuous.

[0075] Textile material

[0076] The invention also relates to a textile material comprising at least one filament as defined above or at least one fiber as defined above.

[0077] Preferably, the textile material according to the invention comprises at least one fiber made of a thermoplastic material. Preferably, the thermoplastic material can be selected from polyamides, polyethylene terephthalates, polypropylenes, polyethylenes, and PEBA copolymers other than that according to the invention. More particularly, the fiber is made of polyamide, preferably selected from PA46, PA6, PA66, PA610, PA612, PA 1010, PA 1012, PAU, PA 12, their copolymers, and mixtures thereof.

[0078] The textile material according to the invention may also comprise one or more synthetic fibers different from those defined above and / or may comprise one or more natural fibers. The natural fibers may be chosen from cotton, wool, and silk; the artificial fibers may be made from natural raw materials, metallic fibers, and / or synthetic fibers other than fibers comprising copolymer filaments as defined above.

[0079] Advantageously, said textile comprises synthetic fibers obtained from bio-based raw materials. Preferably, the textile according to the invention is manufactured solely from bio-based raw materials, such as, for example, textile materials based on PAU, PA1010 and bio-based PEBA.

[0080] By renewable raw materials or bio-based raw materials, we mean materials that include bio-based or renewable carbon. Indeed, unlike materials derived from fossil fuels, materials composed of renewable raw materials contain 14C. The "renewable carbon content" or "bio-based carbon content" is determined in accordance with ASTM D 6866 (ASTM D 6866-06) and, where applicable, ASTM D 7026 (ASTM D 7026-04). The first standard describes a test for measuring the 14C / 12C ratio of a sample and comparing it with the 14C / 12C ratio of a reference sample of 100% bio-based origin, to give a relative percentage of bio-based carbon in the sample. The standard is based on the same concepts as 14C dating, but without making ap The dating equations are applied. The ratio thus calculated is designated as the "pMC" (percent Modern Carbon). If the material to be analyzed is a mixture of biomaterial and fossil material (without radioactive isotopes), then the pMC value obtained is directly correlated to the amount of biomaterial present in the sample. ASTM D 6866-06 proposes several techniques for measuring the 14C isotope content, based either on LSC (Liquid Scintillation Counting) or on AMS / IRMS (Accelerated Mass Spectrometry coupled with Isotope Radio Mass Spectrometry). The measurement method preferably used in the case of the present invention is the mass spectrometry described in ASTM D6866-06 ("accelerator mass spectrometry").

[0081] The textiles of the invention containing PA11 polyamide blocks according to the invention are derived at least in part from bio-based raw materials and therefore have a bio-based carbon content of at least 1%, which corresponds to a 12C / 14C isotopic ratio of at least 1.2 x 10¹⁴. Preferably, the textiles according to the invention comprise at least 50% by mass of bio-based carbon relative to the total mass of carbon, which corresponds to a 12C / 14C isotopic ratio of at least 0.6 x 10¹². This content is advantageously higher, in particular up to 100%, which corresponds to a 12C / 14C isotopic ratio of 1.2 x 10¹². The textiles according to the invention can therefore comprise 100% bio-based carbon or, conversely, result from a mixture with a fossil origin.

[0082] The textile material according to the invention can be a woven, knitted, non-woven or laminated surface.

[0083] According to one embodiment, the textile material according to the invention can consist solely of the elastic filament according to the invention.

[0084] The textile according to the invention advantageously constitutes a felt, a filter, a film, a gauze, a canvas, a dressing, a layer, a fabric, a knit, a clothing item, a garment, a bedding item, a furniture item, a curtain, a cabin covering, a functional technical textile, a geotextile and / or an agrotextile.

[0085] Said textile is advantageously used in the medical field, hygiene, luggage, clothing, apparel, household or home equipment, furniture, carpets, automotive, industry, in particular industrial filtration, agriculture and / or building, more particularly it is a textile material for clothing, parts of sports shoes, sports clothing, sports socks, bags, medical textile materials, bandages, compression stockings.

[0086] The present invention also relates to textile articles obtained by shaping the fiber according to the invention by an extrusion process, in particular by melt extrusion, in In particular, the extrusion of sheets, films, and filaments. Films can thus be obtained by the processes mentioned above using a flat die. The resulting films can undergo one or more processing steps, such as one-dimensional or two-dimensional stretching, heat stabilization treatment, antistatic treatment, and / or sizing.

[0087] The invention also relates to the use of the filament as described above to manufacture a fiber.

[0088] The invention also relates to the use of the filament as described above to manufacture a textile material for clothing, parts of sports shoes, sportswear, socks, in particular sports socks, bags, medical textile materials, bandages, compression stockings.

[0089] The invention also relates to the use of fibers as described above to manufacture a textile material.

[0090] Recycling process

[0091] The invention also relates to a process for recycling filament, fiber or textile material as defined above, comprising the following successive steps: a) grinding the filaments, fibers or said material to obtain particles, b) melting the particles to obtain a molten mixture, and c) the formation of granules from the molten mixture at the end of step b).

[0092] Before these steps, the recycling process may include a step of separating (detaching) the fibers from the structure that contains them, for example. For instance, when the textile comprises fibers according to the invention and fibers incompatible with them, that is, fibers which, in the melted state, lead to an inhomogeneous mixture, then a fiber separation step may prove necessary.

[0093] The grinding step is carried out to reduce the size of the material containing the filaments or fibers according to the invention. Thus, after grinding, particles are obtained that can have, for example, a Dv50 size of 0.1 to 10 mm.

[0094] The grinding step can be carried out in a counter-rotating pin mill, that is to say, a mill comprising a first set of brushes rotating in one direction and a second set of brushes rotating in the opposite direction. Alternatively, the grinding step can be carried out in a hammer mill or a whirl mill.

[0095] The particles obtained after the grinding step are then melted to obtain a molten mixture of the material or fibers. According to some embodiments, the particles are melted in the presence of one or more additives, which may include inert colorants such as titanium dioxide, fillers, surfactants, crosslinking agents, nucleating agents, reactive compounds, and other agents. Flame-retardant minerals or organics, ultraviolet (UV) or infrared (IR) light-absorbing agents, UV or IR fluorescent agents, waxes, thermal stabilizers (phenolic or phosphorus-based, for example), anti-blocking agents, and anti-foaming agents. Typical fillers include talc, calcium carbonate, clay, silica, mica, wollastonite, feldspar, aluminum silicate, alumina, hydrated alumina, glass microspheres, ceramic microspheres, thermoplastic microspheres, barite, and wood flour.

[0096] The particles can be melted at a temperature ranging from 150 to 300°C, and preferably from 180 to 280°C, more particularly from 180 to 250°C.

[0097] Optionally, this process may include a step of filtering the molten mixture in order to remove impurities having, for example, a particle size ranging from 5 pm to 1 mm.

[0098] Finally, the molten mixture, possibly filtered, is then used to form recycled granules. More specifically, the granules can be formed by extrusion.

[0099] When the textile material consists only of elastic filaments according to the invention, during its recycling, the material, after the melting step, results in a homogeneous mixture. The granules obtained can be reused. They can, for example, be used to manufacture elastic filaments.

[0100] When the textile material comprises elastic filaments according to the invention and inelastic PEBA filaments, during its recycling, the material, after the melting step, results in a homogeneous mixture. The resulting granules can be reused. They can, for example, be used to manufacture elastic filaments.

[0101] When the textile material comprises elastic filaments according to the invention and polyamide filaments, during its recycling, the material, after the melting step, results in a homogeneous mixture. The resulting granules can be reused. They can, for example, be used for a purpose other than textiles.

[0102] According to certain embodiments, the recycled granules can be used for the manufacture of the fibers according to the invention.

[0103] According to other embodiments, the recycled granules can in particular be introduced into an extruder or an injection molding machine to manufacture an extruded or injected article

[0104] Other objects and advantages of the present invention will become apparent from the following examples, which are given by way of no limitation whatsoever. Examples

[0105] Example 1 Preparation of copolymers

[0106] The copolymers illustrated in the table below are prepared by mixing the monomers in the molten state.

[0107] The table shows the average number molar mass (g / mol) of the blocks present in the copolymer.

[0108] [Tables] PEBA Block PAU Block PA12 PTMG Enthalpy of fusion (J / g) 1 Comparison - 600 2000 10 2 Invention 600 - 1000 18 3 Invention - 2000 2000 30 4 Invention - 1000 1000 34 5 Invention - 850 2000 15

[0109] Example 2 Manufacturing a filament

[0110] The copolymer 5 is melted and then passed through a die to produce a filament. The filament is drawn out of the die and then cooled by air. The filament is then drawn out to four times its length at room temperature and then released at room temperature. The filament is then heat-set at 100°C. [YES] Example 3 Evaluation of its elasticity

[0112] The elasticity measurement was performed using a dynamometer with a maximum capacity of 10 N. The initial filament length was L0 = 100 mm and the strain rate was 100 mm / min. These conditions allow the yield stress of the filaments to be determined. A preload of 0.02 N was applied at the start of the test to limit the variation in the toe length. A 1-minute pause was applied before each elongation or relaxation. The values ​​are based on a minimum of 5 test specimens or filaments.

[0113] Under these conditions, the monofilament manufactured with copolymer 5, pre-stretched 4x, exhibits an average elastic recovery of 95% over 225% elongation.

[0114] Example 4 Manufacturing of a woven material

[0115] A textile material is produced by weaving PA6 yarns and 10% filament of copolymer 5, in order to give the fabric elasticity. The weaving is carried out according to known techniques.

[0116] Examples Recycling of woven material

[0117] The fabric is ground to reduce it to particles. These are then melted. The molten mixture is homogeneous. Granules are recovered after compounding and cooling.

[0118] It has been observed that these granules can be reused to manufacture elastic filaments.

[0119] Example 6 Manufacturing of a woven material

[0120] An elastic textile material is produced by weaving only filaments made with copolymer 5. The weaving is carried out according to known techniques.

[0121] Example 7 Recycling of woven material

[0122] The fabric is ground to reduce it to particles. These are then melted. The molten mixture is homogeneous. Granules are recovered after compounding and cooling.

[0123] It has been observed that these granules can be reused to manufacture filaments, the elasticity of which is comparable to that of the initial filament.

Claims

Demands

1. Elastic filament comprising a copolymer of polyamide blocks and polyether blocks, -the polyamide blocks being selected from PA 11, PA 12, PA 1010, PA 1012, PA 1014, their copolymer and their mixture, -the polyether blocks being blocks derived from polytetramethylene glycol of number average molar mass between 500 and 3000 g / mol, -the enthalpy of fusion of the copolymer being between 15 and 50 J / g.

2. Filament according to claim 1, characterized in that the weight ratio of polyamide blocks to polyether blocks is between 0.3 and 3.

3. Filament according to claim 1 or 2, characterized in that the hardness of the copolymer is between 30 and 55 ShD.

4. Filament according to any one of the preceding claims, characterized in that the polyamide blocks are selected from PA 11, PA 12, their copolymer and their mixture.

5. Filament according to any one of the preceding claims, characterized in that the number-average molar mass of the polyamide blocks is between 500 and 4000 g / mol, preferably between 600 and 2000 g / mol.

6. Filament according to any one of the preceding claims, characterized in that it is co-extruded with another thermoplastic material selected from polyamides, polyethylene terephthalates, polypropylenes, polyethylenes, PEBA copolymers other than that defined in claims 1 to 5.

7. Filament according to claim 6 characterized in that it has the following structure: core / skin, sea island or trilobed.

8. Fibre comprising at least one filament as defined in any one of claims 1 to 7.

9. Fibre according to claim 8, characterized in that it comprises one or more synthetic filaments different from that defined in claims 1 to 7 and / or one or more natural filaments.

10. Fibre according to claim 8 or 9, characterized in that it is combined with at least one fibre in a thermoplastic matrix different from the copolymer defined in claim 1 to 5.

11. Fibre according to any one of claims 8 to 10, characterized in that it is continuous or discontinuous.

12. Textile material comprising at least one filament as defined in one any of claims 1 to 7 or comprising at least one fiber as defined in any one of claims 8 to 11.

13. Textile material according to claim 12, characterized in that it comprises at least one fiber of a thermoplastic material selected from polyamides, polyethylene terephthalates, polypropylenes, polyethylenes, PEBA copolymers other than that defined in claims 1 to 5, preferably the fiber is polyamide.

14. Textile material according to claim 12 or 13, characterized in that it is a woven, knitted, non-woven, or laminated surface.

15. Textile material according to any one of claims 12 to 14, characterized in that it comprises natural fibers such as cotton, wool, and silk, artificial fibers made from natural raw materials, metallic fibers and / or synthetic fibers other than fibers comprising copolymer filaments as defined in claims 1 to 6.

16. Use of the filament as defined in any one of claims 1 to 6 for the manufacture of textile material for clothing, parts of sports shoes, sportswear, socks, bags, medical textile materials, bandages, compression stockings.

17. A process for recycling filament, fiber or textile material as defined in any one of claims 1 to 15, characterized in that it comprises the following successive steps: a) grinding the filaments, fibers or said material to obtain particles, b) melting the particles to obtain a molten mixture, and c) forming granules from the molten mixture obtained at the end of step b).