Shoe element in contact with the ground

Abstract

The invention relates mainly to a shoe sole, in particular an outsole, made of a composition comprising, by weight relative to the total weight of the composition: 50 to 100% of at least one polyether block amide (PEBA) comprising polyamide blocks and polyether blocks, wherein the polyether blocks comprise on average more than 50% of polyether blocks, wherein the polyether blocks comprise on average more than 50% of ether motifs having at least 3 carbon atoms per oxygen atom; 0 to 50%, preferably 5 to 40% and in particular 10 to 30% of fillers; and 0 to 5%, preferably 0.1 to 4% and in particular 1 to 3% of additives in which the composition has a Shore hardness of less than 100A and a density greater than 0.85, and in which PEBA has a number-average molar mass Mn as measured by size exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol.

Description

Title of the invention: Shoe element in contact with the ground technical field

[0001] This patent application relates to a shoe sole, and more particularly to an outsole of a shoe, intended to be in direct contact with the ground, its manufacturing process as well as its use in the manufacture of shoes and a shoe comprising it. Previous technique

[0002] Shoes generally include an upper and a sole designed to insulate the foot from the ground, to prevent wear, and to contribute to the stabilization and better anchoring of the foot to the ground.

[0003] The sole can be simple, that is, formed of a single layer, or complex, with multiple structures. Thus, in classic shoes, we distinguish the first part, which is placed on the last and receives the stitching that joins the sole to the upper; the shank, a piece that reinforces the sole at the arch; the midsole, a piece placed between the first part and the outsole to increase the thickness of the sole; the outsole; and the heel. In athletic shoes, we generally distinguish the outsole, the midsole, and the insole.

[0004] Soles can be made from a variety of materials, the most common today being natural rubber, polyurethane and PVC. However, these materials are not or are difficult to recycle.

[0005] These materials must meet a large number of requirements. In particular, they are expected to provide significant comfort, and therefore great flexibility, quiet walking, lightness, and high slip resistance. They are also expected to contribute to extending the lifespan of the shoe thanks to their mechanical properties, particularly in terms of elongation at break, tear resistance, and abrasion resistance. Especially for athletic shoes, it is also desirable for the sole to have good responsiveness (elastic rebound). More recently, the requirement that the material be recyclable has been added to these requirements. Finally, these materials are preferably compatible with modern assembly processes such as bonding and overmolding.

[0006] Application WO 2021 / 101970 A1 describes insoles manufactured by extruding a composition comprising thermoplastic elastomer foam particles suspended in a polymer, in particular a thermoplastic polyurethane, polyester, or polyamide. The document mentions poly(ether-block-amides) (PEBA). comprising polyamide and ether blocks. US patent application US2016 / 0302508 A1 describes a shoe comprising an upper and sole made of the same thermoplastic polymer selected from TPU, PA, PET, or PBT. PEBA is mentioned among the polyamides. The outsole may have a Shore hardness between 40A and 80A.

[0007] These soles may, however, have insufficient mechanical properties, particularly in terms of slip resistance on smooth and wet surfaces. They may also be uncomfortable to wear, especially on uneven ground, deform in wet conditions, or produce unwanted noise. Summary of the invention

[0008] The invention therefore aims to provide a shoe sole, in particular an outsole, made of a composition comprising, by weight relative to the total weight of the composition: a. 50 to 100% of at least one polyether block amide (PEBA) comprising polyamide blocks and polyether blocks, comprising on average more than 50% polyether blocks, in which the polyether blocks comprise on average more than 50% ether motifs comprising at least 3 carbon atoms per oxygen atom; b. 0 to 50%, preferably 5 to 40% and in particular 10 to 30% of charges; and c. 0 to 5%, preferably 0.1 to 4% and in particular 1 to 3% of additives,

[0009] wherein the composition has a Shore hardness of less than 100A and a density greater than 0.85, and

[0010] wherein PEBA has an average number-average molar mass Mn as measured by size exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol.

[0011] Preferably, the composition further comprises (d) 0 to 40%, preferably 5 to 30% and in particular 10 to 20% by weight of a polymer other than (a). Advantageously, the composition further comprises (e) 0 to 20%, preferably 2 to 15% and in particular 5 to 10% by weight of rubber.

[0012] Preferably, the PEBA comprises 50 to 90%, in particular 55 to 85% and especially 60 to 80% by weight of polyether blocks. Advantageously, the polyether blocks comprise on average more than 50% by weight of PTMG motifs. Advantageously, the PEBA comprises on average more than 50% by weight of PTMG motifs. Preferably, the PEBA comprises polyamide blocks having 9 or more carbon atoms per amide group, in particular selected from PA10, PAU, PA12, PA513, PA514, PA516, PA518, PA536, PA612, PA613, PA614, PA616, PA618, PA636, PA912, PA104, PA109, PA1010, PA1012, PA1013, PA1014, PA1016, PA1018, PA1036, PA129, PA1210, PA1212, PA1213, PA1214, PA1216, PA1218, PA1236, PA12T, and their copolymers. Preferably, the PEBA comprises 10 to 50%, in particular 15 to 45%, and especially 20 to 40% by weight, of polyamide blocks. Advantageously, the PEBA has a ratio between the number-average molar mass of the polyamide blocks and the number-average molar mass of the polyether blocks of 0.1 to 3.0, preferably 0.2 to 2.0, and especially 0.3 to 1.0.

[0013] According to a second aspect, the invention relates to a method for manufacturing such a sole, comprising the steps of:

[0014] (i) Mix in the molten state, by weight relative to the total weight of the composition:

[0015] a. 50 to 100% of at least one polyether block amide (PEBA) comprising polyamide blocks and polyether blocks, comprising on average more than 50% polyether blocks, in which the polyether blocks comprise on average more than 50% ether motifs comprising at least 3 carbon atoms per oxygen atom;

[0016] b. 0 to 50% of charges; and

[0017] c. 0 to 5% additives,

[0018] the composition having a Shore hardness of less than 100A and a density greater than 0.85, and the PEBA having a number-average molar mass (Mn) as measured by size-exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol; and

[0019] (ii) shape the resulting composition to form a sole.

[0020] Preferably, step (ii) is carried out by injection.

[0021] According to a third aspect, the invention relates to the use of such a sole for the manufacture of a shoe.

[0022] According to a fourth aspect, the invention relates to a shoe, in particular a sports shoe, comprising such a sole. Preferably, these are dress shoes, for example sneakers, sandals, boots or ankle boots; sports shoes, in particular walking, hiking, athletics, running shoes; team sports shoes, in particular indoor sports, for example football, handball, basketball, or volleyball shoes; tennis shoes, table tennis shoes, badminton shoes, skateboard shoes; ski boots or safety shoes.

[0023] According to a fifth aspect, the invention relates to a method for manufacturing such a shoe, comprising the steps of:

[0024] (I) assembly of a sole as described with a shoe upper, in particular by gluing, heat bonding or overmolding.

[0025] According to a sixth and final aspect, the invention relates to a method for recycling such a shoe, comprising the steps of:

[0026] (1) separation of the sole of the shoe, if applicable;

[0027] (2) grinding of the sole to obtain a ground-up;

[0028] (3) heating the ground material obtained in step (2) until melting to obtain a mass fondue; and

[0029] (4) extrusion of the molten mass obtained in step (3) to obtain granules. Description of implementation methods Definition of terms

[0030] The term "sole" generally refers to the part of the shoe located under the foot and in contact with the ground. More specifically, when the sole has several parts, the term refers to the part(s) of the sole that are external in the sense that they come into contact with the ground, particularly the outsole and the heel. In the context of athletic shoes, this is called the outsole, which is distinct from the midsole and the insole.

[0031] The term "thermoplastic elastomer" refers to a polymer comprising rigid and flexible blocks, in the form of a block copolymer, in which the rigid blocks, generally semi-crystalline or having a high glass transition temperature, melt or soften as the temperature increases. Above the melting temperature or the glass transition temperature of the rigid block domains, the material can be processed using conventional thermoplastic polymer processing techniques. Below the melting temperature of the rigid block domains, the thermoplastic elastomer exhibits elastic properties close to those of cross-linked elastomers. PEBAs are explicitly excluded from this definition of thermoplastic elastomers.

[0032] The term “PEBA” is meant to designate a sequenced copolymer comprising rigid blocks and flexible blocks, the rigid blocks being polyamide blocks and the flexible blocks being polyether blocks.

[0033] The term "polyamide" or "PA" refers to a homopolyamide or a copolyamide, such as those obtained from the polycondensation of suitable monomers, in particular lactam, α,co-aminocarboxylic acid and / or dicarboxylic acid and diamine. The nomenclature used to define polyamides is described in ISO 1874-1:1992 "Plastics - Polyamide (PA) materials for molding and extrusion - Part 1: Designation", in particular on page 3 (Tables 1 and 2).

[0034] By "alloy", we mean a homogeneous mixture of polymers (macroscopically, i.e., visible to the naked eye). In one embodiment, the different components of the alloy are linked by one or more covalent bonds.

[0035] In what follows, physical quantities are, unless otherwise stated, measured under normal temperature and pressure conditions, in particular at 23°C and atmospheric pressure. It is further specified that the expressions "between... and..." and "from... to..." used in this description shall be understood including each of the mentioned limits. Finally, unless otherwise stated, percentages are expressed as a percentage of the total weight of the composition. A. Sole

[0036] According to a first aspect, the invention relates to a shoe sole, in particular a wear sole or an outsole, made of a composition comprising a specific PEBA and having a particular hardness and density.

[0037] The sole can in principle be of any shape, provided that it is compatible with its main functions of insulating the foot from the outside, preventing wear, and contributing to the stabilization and better anchoring of the foot to the ground. Nevertheless, it is generally essentially flat and follows the shape of the sole of the human foot.

[0038] The dimensions of the sole will depend on the size of the shoe. However, the sole generally has a maximum width of between 50 and 150 mm, preferably 70 to 120 mm and particularly 80 and 100 mm, and a maximum length of between 50 and 500 mm, preferably 80 to 400 mm and particularly 100 to 350 mm. The maximum thickness of the sole most often varies between 0.05 and 24 mm, preferably between 0.1 and 10 mm and advantageously between 0.5 and 5 mm. The length of the sole is generally between 9 and 40 cm.

[0039] Preferably, the sole is designed to allow both good grip on the ground and easy drainage of water. To this end, the sole may, for example, have grooved and / or protruding parts distributed regularly or irregularly over its surface. In particular, the sole may have, especially on the face intended to be in contact with the ground, grooves and protrusions forming patterns. Advantageously, the grooves form one or more continuous channels leading from the central part of the sole to its edge, thus allowing water to drain to the lateral side of the sole. These grooves preferably have a depth of 0.05 to 10 mm, in particular 0.1 to 5 mm, advantageously 0.2 to 3 mm, for a size 42 sole. The width of the grooves is preferably 0.5 to 100 mm, in particular 1 to 80 mm and advantageously 2 to 50 mm, for a size 42 sole.

[0040] Alternatively, the sole may be provided with one or more studs distributed over its surface. These studs are preferably made of a composition similar to that of the sole, in order to facilitate manufacturing and recycling.

[0041] The contact area between the sole and a rigid surface such as an aluminum plate, measured according to the method described in the publication by Moncalero et al., (International Journal of Industrial Ergonomics, Vol. 61, September 2017, pages 62-70) by applying a nominal force of 400N to the sole, represents preferably at least 40%, in particular 45 to 95%, especially 50 to 90% and advantageously 60 to 85% of the sole surface.

[0042] As mentioned above, the sole may comprise one or more parts, for example, 1 to 5 parts, preferably 1 to 3 parts, advantageously 1 or 2 parts. For example, the sole may comprise one part at the front of the foot and another at the heel, these two parts not necessarily being joined at the sole of the foot. The sole may also be formed from a single piece extending from the toe to the heel.

[0043] According to the invention, the sole is made of a composition comprising, by weight relative to the total weight of the composition: a. 50 to 100% of at least one polyether block amide (PEBA) comprising polyamide blocks and polyether blocks, wherein the polyether blocks comprise on average more than 50% polyether blocks, wherein the polyether blocks comprise on average more than 50% ether motifs comprising at least 3 carbon atoms per oxygen atom; b. 0 to 50%, preferably 5 to 40% and in particular 10 to 30% of charges; and c. 0 to 5%, preferably 0.1 to 4% and in particular 1 to 3% of additives

[0044] wherein the composition has a Shore hardness of less than 100A and a density greater than 0.85, and wherein PEBA has an average number molar mass Mn as measured by size exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol. PEBA

[0045] The composition therefore comprises, as a main component, a particular polyether block amide (PEBA).

[0046] PEBAs result from the polycondensation of reactive-end polyamide blocks with reactive-end polyether blocks. In particular, PEBAs can result from the polycondensation of: 1. Polyamide blocks with diamine ends and polyoxyalkylene blocks with dicarboxylic ends; or 2. Polyamide blocks with dicarboxylic ends with polyetherdiols (polyoxyalkylene α,co-dihydroxylated blocks), the products obtained in this case being polyetheresteramides.

[0047] According to the invention, the PEBA in the composition comprises at least 50%, preferably 50 to 90%, in particular 55 to 85% and especially 60 to 80% by weight of polyether blocks.

[0048] The polyether blocks essentially comprise or are made up of alkylene oxide motifs.

[0049] The polyether blocks comprise on average more than 50%, in particular more than 60%, especially more than 70%, more specifically more than 80%, particularly more than 90%, and particularly preferably 100% by weight of ether units comprising at least 3, and in particular at least 4, carbon atoms per oxygen atom. Preferably, a PEBA in which 80 to 100%, preferably 90 to 100%, and advantageously 95 to 100% by weight of the polyether blocks comprise at least 3, and in particular 4, carbon atoms per oxygen atom. Indeed, a PEBA with such polyether blocks exhibits reduced hydrophilicity and therefore a low affinity for water, reducing water absorption, particularly during use in wet weather, and improving dimensional stability over time.

[0050] These may include PPG (polypropylene glycol) blocks, consisting of propylene oxide motifs, PO3G (polytrimethylene glycol) blocks, consisting of polytrimethylene glycol ether motifs, and / or PTMG (polytetrahydrofuran) blocks, consisting of tetramethylene glycol motifs, with PTMG blocks being preferred.

[0051] PEBAs may include polyether blocks comprising several distinct polyether motifs, these copolyethers being able to be block or statistical.

[0052] Preferably, the PEBA in the composition comprises up to 50%, in particular 10 to 50%, in particular 15 to 45% and in particular 20 to 40% by weight of polyamide blocks.

[0053] Indeed, when the polyamide block content in the PEBA is higher, the PEBA does not adapt sufficiently to the surface irregularities, and therefore does not create the necessary grip with the substrate to achieve a coefficient of friction required for slip resistance, particularly on wet surfaces. Such PEBA also results in discomfort during use, especially on uneven ground.

[0054] Polyamide blocks with dicarboxylic acid ends are obtained, for example, from the condensation of polyamide precursors in the presence of a dicarboxylic acid acting as a chain-limiting agent. Polyamide blocks with diamine ends are obtained, for example, from the condensation of polyamide precursors in the presence of a diamine acting as a chain-limiting agent.

[0055] Three types of polyamide blocks can be used advantageously.

[0056] According to a first type, the polyamide blocks are obtained from the condensation of a dicarboxylic acid preferably having 4 to 36, in particular 4 to 20, and in particular 6 to 18 carbon atoms, and a diamine preferably having 2 to 20, in particular 6 to 14 carbon atoms.

[0057] The dicarboxylic acid may be, in particular, an aliphatic, cycloaliphatic, or aromatic dicarboxylic acid. Examples of dicarboxylic acids include butanedioic acid, adipic acid, azelaic acid, and suberic acid. sebacic acid, dodecanedicarboxylic acid, brassylic acid, thapsic acid, octadecanedicarboxylic acid, 1,4-cyclohexyldicarboxylic acid, terephthalic (T) acid, isophthalic (I) acid and dimerized fatty acids.

[0058] Dimerized fatty acids preferably have a dimer content of at least 98%; preferably they are hydrogenated; these are for example the products marketed under the brand "PRIPOL" by the company "CRODA", or under the brand EMPOL by the company BASF, or under the brand Radiacid by the company OLEON, and polyoxyalkylenes α,co-diacids.

[0059] The diamine may be, in particular, an aliphatic, cycloaliphatic or aromatic diamine. By way of example, tetramethylenediamine, cadaverine, rhexamethylenediamine, 1,10-decamethylenediamine, 1,12-dodecamethylenediamine, trimethylhexamethylenediamine, the isomers of bis-(4-aminocyclohexyl)methane (BACM), bis-(3-methyl-4-aminocyclohexyl)methane (BMACM), and 2-2-bis-(3-methyl-4-aminocyclohexyl)-propane (BMACP), p-amino-di-cyclohexylmethane (PACM), isophoronediamine (IPDA), 2,6-bis-(aminomethyl)norbomane (BAMN) and piperazine (Pip).

[0060] The polyamide block of the first type is preferably chosen from PA 412, PA 414, PA 418, PA 513, PA 516, PA 610, PA 612, PA 613, PA 614, PA 618, PA 912, PA 1010, PA 1012, PA 1014 and PA 1018.

[0061] According to a second type, the polyamide blocks result from the condensation of one or more α,co-aminocarboxylic acids and / or one or more lactams in the presence of a dicarboxylic acid having from 4 to 18 carbon atoms or a diamine.

[0062] Examples of α,co-amino carboxylic acids include aminocaproic, amino-7-heptanoic, amino-10-decanoic, amino-11-undecanoic and amino-12-dodecanoic acids.

[0063] The lactams are preferably chosen from those which preferably comprise 6 to 12 carbon atoms, in particular caprolactam, oenantholactam and lauryllactam.

[0064] Advantageously, the polyamide blocks of the second type are chosen from the PA 10, PA 11 and PA 12 blocks.

[0065] According to a third type, the polyamide blocks result from the condensation of monomers of the first and second type as described above respectively, for example of at least one α,co-aminocarboxylic acid or lactam with at least one diamine and at least one dicarboxylic acid.

[0066] Examples of third-type polyamide blocks include PA 66 / 6 and PA 66 / 610 / 11 / 12.

[0067] Advantageously, the PEBA thus comprises one or more polyamide blocks selected from PA 10, PA 11, PA 12, PA 54, PA 59, PA 510, PA 512, PA 513, PA 514, PA 516, PA 518, PA 536, PA 64, PA 66, PA 69, PA 610, PA 612, PA 613, PA 614, PA 616, PA 618, PA 636, PA 912, PA 104, PA 109, PA 1010, PA 1012, PA 1013, PA 1014, PA 1016, PA 1018, PA 1036, PA 10T, PA 124, PA 129, PA 1210, PA 1212, PA 1213, PA 1214, PA 1216, PA 1218, PA 1236, PA 12T, and their copolymers.

[0068] Particularly preferred are polyamide blocks comprising 7 or more, in particular 9 or more carbon atoms per amide group. These polyamides can notably be chosen from PA 10, PA 11, PA 12, PA 513, PA 514, PA 516, PA 518, PA 536, PA 612, PA 613, PA 614, PA 616, PA 618, PA 636, PA 912, PA 104, PA 109, PA 1010, PA 1012, PA 1013, PA 1014, PA 1016, PA 1018, PA 1036, PA 129, PA 1210, PA 1212, PA 1213, PA 1214, PA 1216, PA 1218, PA 1236, PA 12T, and their copolymers.

[0069] Particularly preferred PEBAs comprise polyamide PA 11 blocks and polyether PTMG blocks or polyamide PA 11 blocks and polyether PTMG blocks.

[0070] Particularly preferred are the polyamide blocks of PEBA selected from the PA 11, PA 12, PA 10, PA 1010 and PA 1012 blocks, especially PA 11 and PA 12, and the polyether blocks of PEBA selected from the polyethylene glycol and polytetrahydrofuran blocks. The particularly preferred PEBAs comprise blocks of PA 11 and PTMG or of PA 12 and PTMG.

[0071] PEBAs can be obtained, in particular, by copolycondensation of polyetherdiol with carboxyl-terminated polyamides. The general two-step method for preparing PEBA copolymers having ester bonds between the PA and PE blocks is described, for example, in document FR 2846332. The general method for preparing PEBA copolymers having amide bonds between the PA and PE blocks is described, for example, in document EP 1482011. The polyether blocks can also be mixed with polyamide precursors and a diacid chain limiter to prepare polymers with polyamide and polyether blocks having statistically distributed motifs (one-step process).

[0072] In addition to polyamide and polyether blocks, PEBAs may include other additional blocks. For example, PEBA may comprise three different types of blocks ("triblock"). This triblock may, for example, comprise a polyamide block, a polyether block, and a polyester block. Alternatively, it may comprise a polyamide block and two different polyether blocks, for example, a PPG block and a PTMG block. Preferred triblock PEBAs are copolyetheresteramides.

[0073] The number-average molar mass (Mn) of the polyamide blocks in the PEBA is preferably 400 to 20,000 g / mol, in particular 500 to 10,000 g / mol. Preferably, the number-average molar mass of the polyamide blocks in the PEBA is less than 4,000 g / mol, and in particular less than 3,000 g / mol. In some embodiments, the number-average molar mass of the polyamide blocks in the PEBA is 600 to 700 g / mol. or 700 to 800 g / mol, or 800 to 900 g / mol, or 900 to 1000 g / mol, or 1000 to 1100 g / mol, or 1100 to 1200 g / mol, or 1200 to 1300 g / mol, or 1300 to 1400 g / mol, or 1400 to 1500 g / mol, or 1500 to 1600 g / mol, or 1600 to 1700 g / mol, or 1700 to 1800 g / mol, or 1800 to 1900 g / mol, or 1900 to 2000 g / mol.

[0074] The number-average molar mass Mn of the polyether blocks is preferably 100 to 6000 g / mol, in particular 500 to 3000 g / mol. Preferably, the number-average molar mass of the polyether blocks is greater than 900 g / mol. In some embodiments, the number-average molar mass of the polyether blocks is 1000 to 1200 g / mol, or 1200 to 1400 g / mol, or 1400 to 1600 g / mol, or 1600 to 1800 g / mol, or 1800 to 2000 g / mol.

[0075] The number-average molar mass (Mn) of the respective blocks can be adjusted by the chain limiter content. It can be calculated according to the following relationship:

[0076] [Math.l] X iMÎVv ssMïf eksdisc ds

[0077] In this formula, nmonomer represents the number of moles of monomer, nichainimulator represents the number of moles of excess diacid limiter, MWrepeater represents the molar mass of the repeating motif, and MWichainimulator represents the molar mass of the excess diacid.

[0078] The number-average molar mass of the polyamide blocks and the polyether blocks can be measured before copolymerization of the blocks by gel permeation chromatography (GPC), according to ISO 16014-1:2019.

[0079] Preferably, the PEBA has a ratio between the number-average molar mass of the polyamide blocks and the number-average molar mass of the polyether blocks of 0.1 to 3.0, in particular from 0.2 to 2.0, and especially from 0.3 to 1.0. This ratio can be calculated by dividing the number-average molar mass of the polyamide blocks by the number-average molar mass of the polyether blocks. In particular, the mass ratio of the polyamide blocks to the polyether blocks of the PEBA can be from 0.2 to 0.5, or from 0.5 to 0.7, or from 0.7 to 1.0, or from 1.0 to 1.5, or from 1.5 to 2.0. Indeed, when this ratio is too high, the material is too rigid, which leads to poor slip resistance on smooth and wet surfaces, and also to discomfort when walking, particularly on uneven ground. Conversely, when this ratio is too low, the material is too flexible and therefore no longer sufficiently resists abrasion, reducing the lifespan of the shoe.

[0080] The PEBA in the composition has an average number molar mass Mn as measured by size exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol, preferably between 20,000 and 70,000 g / mol, advantageously between 30,000 and 70,000 g / mol.

[0081] PEBAs are commercially available, and sold in particular by Arkema under the name PEBAX®, by Evonik under the name Vestamid®, by EMS under the name Grilamid® and by Sanyo under the name Pelestat®. Other polymers

[0082] Advantageously, the composition may include, in addition to the PEBA(s), other polymers, in particular one or more other different thermoplastic polymers.

[0083] Thus, according to a preferred embodiment, the composition further comprises (d) 0 to 40%, preferably 5 to 30% and in particular 10 to 20% by weight of one or more thermoplastic polymers different from (a), in particular thermoplastic elastomers.

[0084] The thermoplastic polymer (d) may in particular be selected from polyolefins, in particular polypropylene (PP) and polyethylene (PE) and functionalized polyolefins, polyamides, polyesters such as polyethylene terephthalate (PET), polylactic acid (PLA) and poly(butylene succinate (PBS), polystyrene, acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC) and polymethyl methacrylate (PMMA).

[0085] Preferably, the thermoplastic polymer (d) has a Shore hardness of less than 100A, in particular less than 90A and especially less than 80A.

[0086] Preferably, the thermoplastic polymer (d) is a thermoplastic elastomer. The thermoplastic elastomer can be chosen in particular from a thermoplastic polyurethane (TPU), a styrene copolymer, a polyester elastomer, with thermoplastic polyurethane (TPU) and styrene copolymer being preferred.

[0087] In the thermoplastic elastomer, the soft blocks and the rigid blocks can be covalently linked by functions chosen from among the CC bonds, amides, esters, methanes, or ureas.

[0088] This may include a thermoplastic polyurethane (TPU). It generally results from the reaction of at least one polyisocyanate (X) with at least one compound reactive with the isocyanate, preferably having two functional groups reactive with the isocyanate, more preferably a polyol, and optionally with a chain extender, optionally in the presence of a catalyst.

[0089] The rigid blocks of the TPU can be blocks of motifs derived from polyisocyanates and chain extenders while the flexible blocks mainly comprise motifs derived from compounds reactive with isocyanate, preferably polyols.

[0090] The polyisocyanate may be aliphatic, cycloaliphatic, araliphatic, and / or aromatic. Preferably, the polyisocyanate is a diisocyanate. Advantageously, the polyisocyanate is selected from the group consisting of tri-, tetra-, penta-, hexa-, hepta-, and / or octamethylene diisocyanate, and 2-methylpentamethylene 1,5-düsocyanate, 2-ethylbutylene-1,4-diisocyanate, 1,5-pentamethylene diisocyanate, 1,4-butylene diisocyanate, l-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane (isophorone diisocyanate, IPDI), 1,4-bis(isocyanatomethyl)cyclohexane, 1,3-bis(isocyanatomethyl)cyclohexane (HXDI), 2,4-paraphenylene diisocyanate (PPDI), 2,4-tetramethylene xylene diisocyanate (TMXDI), 4,4'-, 2,4'- and / or 2,2'-dicyclohexylmethane diisocyanate (H12 MDI), 1,4-cyclohexane diisocyanate, l-methyl-2,4- and / or l-methyl-2,6-cyclohexane diisocyanate, 2,2'-, 2,4'- and / or 4,4'-diphenylmethane diisocyanate (MDI), 1,5-naphthylene diisocyanate (NDI), 2,4- and / or 2,6-toluene diisocyanate (TDI), diphenylmethane diisocyanate, 3,3'-dimethyl-diphenyl diisocyanate, 1,2-diphenylethane diisocyanate, phenylene diisocyanate, methylene bis (4-cyclohexylisocyanate) (HMDI) and mixtures thereof.Preferably, the polyisocyanate is selected from the group consisting of diphenylmethane diisocyanates (MDI), toluene diisocyanates (TDI), pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), methylene bis(4-cyclohexylisocyanate) (HMDI), and mixtures thereof. Even more preferably, the polyisocyanate is 4,4'-MDI (4,4'-diphenylmethane diisocyanate), 1,6-HDI (1,6-hexamethylene diisocyanate), or a mixture thereof. Advantageously, it does not comprise any cycloaliphatic diisocyanate. Preferably, the polyisocyanate is aliphatic.

[0091] The compound(s) reactive with isocyanate preferably have an average functionality between 1.8 and 3, more preferably between 1.8 and 2.6, and even more preferably between 1.8 and 2.2. The average functionality of the compound(s) reactive with isocyanate corresponds to the number of isocyanate-reactive functions of the molecules, calculated theoretically for one molecule from a quantity of compounds. Preferably, the compound reactive with isocyanate has, according to a statistical average, a number of active Zerewitinoff hydrogens in the above ranges.

[0092] Advantageously, the compound that reacts with the isocyanate has at least one reactive group selected from among the hydroxyl group, the amine group, the thiol group, and the carboxylic acid group. Preferably, the compound that reacts with the isocyanate has at least one hydroxyl reactive group, and more preferably several hydroxyl groups. Thus, particularly advantageously, the compound that reacts with the isocyanate comprises or consists of a polyol.

[0093] Preferably, the compound reactive with the isocyanate has a number-average molar mass, as determined by GPC, according to ISO 16014-1:2012, of 500 to 100000 g / mol, in particular of 500 to 8000 g / mol, preferably still of 700 to 6000 g / mol, in particular of 800 to 4000 g / mol.

[0094] Preferably, the polyol is selected from the group consisting of polyester polyols, polyether polyols, polycarbonate diols, polyalkylene diols, and mixtures thereof. More preferably, the polyol is a polyether polyol, a polyester polyol, and / or a polycarbonate diol, such that the flexible blocks of the thermoplastic polyurethane are polyether blocks, polyester blocks, and / or polycarbonate blocks, respectively. Even more preferably, the flexible blocks of the thermoplastic polyurethane are polyether blocks and / or polyester blocks (the polyol being a polyether polyol and / or a polyester polyol).

[0095] Examples of polyester polyols include polycaprolactone polyols and / or copolyesters based on one or more carboxylic acids selected from adipic acid, succinic acid, pentanedioic acid and / or sebacic acid and one or more alcohols selected from 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol and / or polytetrahydrofuran. Preferably, the polyol is not a cycloaliphatic diol.

[0096] More particularly, the copolyester may be based on adipic acid and a mixture of 1,2-ethanediol and 1,4-butanediol, or the copolyester may be based on adipic acid, succinic acid, pentanedioic acid, sebacic acid or mixtures thereof, and polytetrahydrofuran (tetramethylene glycol), or the copolyester may be a mixture of these copolyesters.

[0097] As a polyether polyol, polyetherdiols (i.e., aliphatic α,co-dihydroxylated polyoxyalkylene blocks) are preferably used. Preferably, the polyether polyol is a polyetherdiol based on ethylene oxide, propylene oxide, and / or butylene oxide, a block copolymer based on ethylene oxide and propylene oxide, polyethylene glycol, polypropylene glycol, polybutylene glycol, polytetrahydrofuran, polybutane diol, or a mixture thereof.

[0098] The polyether polyol is preferably a polytetrahydrofuran (flexible blocks of thermoplastic polyurethane being therefore blocks of polytetrahydrofuran) and / or a polypropylene glycol (flexible blocks of thermoplastic polyurethane being therefore blocks of polypropylene glycol) and / or a polyethylene glycol (flexible blocks of thermoplastic polyurethane being therefore blocks of polyethylene glycol), preferably a polytetrahydrofuran having an average number molar mass of 500 to 15000 g / mol, preferably of 1000 to 3000 g / mol.

[0099] The polyalkylene diols usable in the invention are preferably butadiene-based.

[0100] One or more polyols may be used as a reactive compound with the isocyanate.

[0101] In a particularly preferred manner, the flexible blocks of the TPU are blocks of polytetrahydrofuran, polypropylene glycol and / or polyethylene glycol.

[0102] Preferably, a chain extender (Y) is used for the preparation of the thermoplastic polyurethane, in addition to the isocyanate and the compound reactive with the isocyanate.

[0103] The chain extender may be aliphatic, araliphatic, aromatic and / or cycloaliphatic.

[0104] It advantageously has a number-average molar mass of 50 to 499 g / mol. The number-average molar mass can be determined by GPC, preferably according to ISO 16014-1:2012. The chain extender preferably has two reactive groups with the isocyanate (also called "functional groups").

[0105] A single chain extender or a mixture of at least two chain extenders can be used.

[0106] The chain extender is preferably bifunctional. Examples of extenders The chains are diamines and alkanediols having from 2 to 10 carbon atoms. In particular, the chain extender can be chosen from the group consisting of 1,2-ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanediol, 1,4-dimethanol cyclohexane, neopentyl glycol, hydroquinone bis(beta-hydroxyethyl) ether (HQEE), di-, tri-, tetra-, penta-, hexa-, hepta-, octa-, nona- and / or deca-alkylene glycol, their respective oligomers, polypropylene glycol and mixtures thereof. More preferably, the chain extender is chosen from the group consisting of 1,2-ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and mixtures thereof, and more preferably it is chosen from 1,3-propanediol, 1,4-butanediol and / or 1,6-hexanediol.Even more preferably, the chain extender is a mixture of 1,4-butanediol and 1,6-hexanediol, more preferably in a molar ratio of 6:1 to 10:1.

[0107] Preferably, the TPU is semi-crystalline. Its melting temperature Tf is preferably between 100°C and 230°C, and more preferably between 120°C and 160°C. The melting temperature can be measured according to ISO 11357-3 Plastics - Differential scanning calorimetry (DSC) Part 3.

[0108] Advantageously, the TPU can be recycled TPU and / or partially or completely bio-based TPU.

[0109] Advantageously, the rigid polyurethane block is composed of a diisocyanate selected from 4,4'-MDI, HDI or PDI and / or a diol selected from butanediol, propanediol, pentanediol and hexanediol.

[0110] The mass ratio between the rigid polyurethane blocks and the flexible polyol blocks of the TPU is preferably less than or equal to 1.0, in particular less than 0.9, and in particular less than 0.8. According to one embodiment, this mass ratio is from 0.1 to 1.0, preferably from 0.2 to 0.8 and in particular from 0.3 to 0.5.

[0111] According to one embodiment, PEBA forms an alloy with the thermoplastic elastomer.

[0112] Thus, TPU and PEBA can be linked by one or more covalent bonds, for example by a urethane function. Up to 10% by weight, in particular up to 5% by weight, of PEBA can thus be covalently linked to the thermoplastic polyurethane, preferably by a urethane function. Rubber

[0113] According to one embodiment, the composition further comprises (e) 0 to 30%, preferably 5 to 25% and in particular 5 to 20% by weight of rubber.

[0114] The rubber may in particular be a synthetic rubber selected from the group consisting of bromobutyl rubber, butyl rubber, polyisoprene rubber, polynorbomene rubber, ethylene-propylene rubber (EPR), ethylene-propylene-diene rubber (EPDM), nitrile rubber (NBR), carboxylated nitrile rubber, polychloroprene rubber (neoprene rubber), polysulfide rubber, polyacrylic rubber, silicone rubber, chlorosulfonated polyethylene rubber, polybutadiene rubber, styrene-butadiene rubber (SBR), butyl rubbers (isobutylene-isoprene) or one of their mixtures.

[0115] Among these, polyisoprene rubber, ethylene-propylene-diene rubber (EPDM), nitrile rubber (NBR), polybutadiene rubber, styrene-butadiene rubber (SBR), butyl rubber (isobutylene-isoprene), styrene-butadiene rubber, and mixtures thereof are particularly preferred. Butadiene rubber is particularly preferred. Charges

[0116] According to the invention, the composition of the sole also comprises 0 to 50% by weight, preferably 5 to 40% by weight, in particular 10 to 30% by weight of fillers relative to the total weight of the composition.

[0117] These may include mineral or organic fillers. Mineral fillers include, in particular, metal oxides and carbonates such as silica, calcium carbonate and zinc oxide, aluminum oxides, calcium carbonate and aluminosilicates, as well as carbon black or molybdenum disulfide. Organic fillers include, in particular, PTFE powder and aramid powder. Mineral fillers are preferred.

[0118] These fillers are generally in powder form but can also be in other forms, including fibers. Additives

[0119] According to the invention, the composition also comprises 0 to 5%, preferably 0.1 to 4% and in particular 0.5 to 3% by weight of additives relative to the total weight of the composition.

[0120] The additive(s) may be chosen in particular from among catalysts, antioxidants, thermal stabilizers, UV stabilizers, light stabilizers, lubricants, flame retardants, nucleating agents, crosslinking agents, anti-abrasion agents, chain extenders, pigments and dyes.

[0121] According to a preferred embodiment, the composition comprises 0.05 to 0.2% by weight of one or more antioxidant and / or UV-stabilizing agents. In particular, a phenolic agent combined with a phosphite compound may be used for this purpose. Composition

[0122] Advantageously, the PEBA composition is homogeneous when examined with the naked eye and forms a non-heterogeneous, for example non-porous, medium. Nevertheless, the sole may, for reasons of weight reduction or aesthetics, for example, have one or more cutouts.

[0123] According to the invention, the density of the sole composition, as measured according to ISO 1183-1, is greater than 0.85. Preferably, the density is less than 1.5 and in particular it is from 0.9 to 1.2. Advantageously, the composition is not lightened, in particular not foamed.

[0124] Due to its particular constitution, the sole of the invention has a set of interesting properties.

[0125] First of all, it has excellent mechanical properties, including high resistance to slipping on smooth and wet surfaces, which greatly improves grip on wet grass, for example.

[0126] The sole also advantageously exhibits high responsiveness (elastic rebound), as evidenced by the measurement of a low damping factor (tangent delta). The tangent delta is measured on a film approximately 250 µm thick obtained by pressing the granules in a mold above their melting temperature under a 2T load. The test is performed by DMA (Dynamic Mechanical Analysis) in tension according to ISO 6721, carrying out a temperature sweep from -100 to 180°C at a rate of 2°C / min and at a frequency of 1 Hz and an amplitude of 20 µm. The value of tan delta then corresponds to the maximum of the curve obtained. The value of the tangent delta over the measurement range remains below 0.3, advantageously below 0.2.

[0127] The sole also has a Shore hardness, as measured according to ISO 7619-1 after 3s, of less than 100A, preferably 50A to 95A, preferably 60A to 90A and in particular 70A to 85A.

[0128] Finally, it advantageously exhibits an elongation at break as measured according to ISO 527 greater than 400%.

[0129] The sole of the invention also provides great comfort in use. First, the flexibility of the material, even at low temperatures, makes it more comfortable, particularly on uneven ground, and reduces unwanted squeaking noises. Furthermore, the composition is lighter than rubber and aromatic TPU, which makes the shoe lighter.

[0130] Finally, the essentially thermoplastic composition of the sole facilitates its manufacture and recycling.

[0131] According to a preferred embodiment, the sole is made of a composition comprising, by weight relative to the total weight of the composition: a. 50 to 100%, preferably 60 to 95%, and in particular 70 to 90% of at least one polyether block amide (PEBA) comprising polyamide blocks and polyether blocks, wherein the polyether blocks comprise on average more than 50% of ether motifs having at least 3 carbon atoms per oxygen atom; b. 0 to 50%, preferably 5 to 40% and in particular 10 to 30% of charges; c. 0 to 5%, preferably 0.1 to 4% and in particular 1 to 3% of additives; d. 5 to 30% and in particular 10 to 20% by weight of one or more elastomers thermoplastics other than (a); and e. 2 to 25% and in particular 5 to 20% by weight of rubber,

[0132] wherein the composition has a Shore hardness of less than 100A and a density greater than 0.85, and wherein PEBA has a number-average molar mass Mn as measured by size exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol. A. Sole manufacturing process

[0133] According to a second aspect, the invention relates to a method for manufacturing a sole according to the invention, comprising the steps of:

[0134] (i) Mix in the molten state, by weight relative to the total weight of the composition:

[0135] a. 50 to 100% of at least one polyether block amide (PEBA) comprising polyamide blocks and polyether blocks, comprising on average more than 50% polyether blocks, wherein the polyether blocks comprise on average more than 50% ether motifs comprising at least 3 carbon atoms per oxygen atom;

[0136] b. 0 to 50% charges; and

[0137] c. 0 to 5.3% additives,

[0138] the composition having a Shore hardness of less than 100A and a density greater than 0.85, and the PEBA having a number-average molar mass (Mn) as measured by size-exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol; and

[0139] (ii) Shape the resulting composition to form a sole.

[0140] Step (i) of the process can in particular be carried out by heating under high shear, for example in an extruder, so as to allow good dispersion of the molten components and the obtaining of a homogeneous mixture.

[0141] The sole of the invention can be manufactured by any means known to a person skilled in the art. Preferably, it is manufactured by injection molding. Therefore, step (ii) can advantageously be carried out by injection molding. B. Usage

[0142] According to a third aspect, the invention relates to the use of a sole of the invention, in particular an outsole, for the manufacture of a shoe.

[0143] This may include dress shoes, for example sneakers, sandals, boots or ankle boots, or sports shoes, including walking, hiking, athletics, running, team sports, especially indoor sports, for example football, handball, basketball, or volleyball, tennis shoes, table tennis, badminton, skateboarding shoes, ski boots or even professional shoes such as safety shoes.

[0144] The shoe can be manufactured by any means known to a person skilled in the art. Thus, for example, the outsole can be assembled with the midsole and the upper, and then the insole is inserted into the shoe thus formed.

[0145] According to an advantageous embodiment, the upper comprises or is made of polyamide or PEBA. Such a sole and upper assembly is easily recyclable, unlike an assembly with a sole comprising or made of non-recyclable materials such as rubber. C. Shoe

[0146] According to a fourth aspect, the invention relates to a shoe, in particular a sports shoe, comprising a sole as described above.

[0147] Preferably, these are dress shoes, for example sneakers, trainers, sandals, boots or ankle boots. They can also be sports shoes, in particular walking, hiking, athletics, running, team sports, especially indoor sports, for example football, handball, basketball, or volleyball, tennis shoes, table tennis shoes, badminton shoes, skateboarding shoes, ski boots or safety shoes. Its use for the manufacture of sports shoes, including running shoes, ski boots or hiking shoes.

[0148] The shoe generally comprises, in addition to the sole, an upper surrounding the foot. The upper is advantageously made partially or entirely of thermoplastic polymer, preferably polyamide or PEBA.

[0149] Preferably, the polyamide is a polyamide with at least 7, in particular at least 9 carbon atoms per polyamide motif, specifically PA11 or PA12.

[0150] The PEBA intended for the manufacture of the stem preferably comprises, relative to the total polyamide blocks, at least 80 to 100%, in particular 90 to 100% and especially 95 to 100% by weight of polyamide blocks with at least 7, in particular at least 9 carbon atoms per polyamide unit, preferably PA11 or PA12 blocks. Furthermore, the PEBA preferably comprises, relative to the total polyether blocks, at least 80 to 100%, in particular 90 to 100% and especially 95 to 100% by weight of polyether blocks with at least 3, in particular at least 4 carbon atoms per ether oxygen, preferably PTMG blocks. A PEBA comprising PA11 and PTMG blocks or PA12 and PTMG blocks is particularly preferred.

[0151] According to one embodiment, the polyamide and / or PEBA may comprise 0 to 60% by weight of additives or fillers, in particular chosen from those described above for the composition of the sole.

[0152] The shoes of the invention have, in addition to their good performance and excellent comfort, the advantage of having a long lifespan. D. Shoe manufacturing process

[0153] The sole thus manufactured can then be assembled with other components such as an upper to form a shoe.

[0154] Also, according to a fifth aspect, the invention relates to a method for manufacturing a shoe as described above, comprising the steps of:

[0155] (I) assembly of a sole according to the invention with a shoe upper, including by sewing, gluing, heat bonding or overmolding.

[0156] According to a preferred embodiment, the outsole can be assembled with the midsole without the use of glue. In another embodiment, the outsole is then used as an insert and the midsole is overmolded by injection.

[0157] Advantageously, the midsole is made of a composition comprising 50% to 100%, in particular 60% to 100% and advantageously 70% to 100% by weight of PEBA or aliphatic TPU, preferably PEBA. The PEBA and TPU may in particular be selected from those described above with regard to the sole.

[0158] Preferably, the midsole comprises or is made of the composition in foam form. In this case, it is preferable that the foaming be carried out using a supercritical fluid. E. Shoe recycling process

[0159] The shoes thus obtained have, in addition to the advantages mentioned, also that of being easily recyclable.

[0160] Also, according to a sixth aspect, the invention relates to a method for recycling such a shoe, comprising the steps of: a. Separation of the sole from the upper, if applicable; b. Grinding the sole to obtain a mulch; c. Heating the ground material obtained in step (a) until melted to obtain a molten mass; and d. Extrusion of the molten mass obtained in step (b) to obtain granules.

[0161] The invention will be explained in more detail in the examples that follow. Examples

[0162] In order to evaluate properties of interest for the manufacture of soles, the following thermoplastic elastomer compositions were prepared and tested. The number molar masses were determined by size exclusion chromatography according to ISO 16014-1:2019.

[0163] PEBA 1: PA11 (600 g / mol) and PTMG (1000 g / mol) block copolymer with 62.5% PTMG, with a number molar mass of 60,000 g / mol.

[0164] PEBA 2: PA12 (850 g / mol) and PTMG (2000 g / mol) block copolymer with 70.2% PTMG, number molar mass of 61000 g / mol.

[0165] PEBA 3: PA12 (600 g / mol) and PTMG (2000 g / mol) block copolymer with 76.9% PTMG, number molar mass 66,000 g / mol.

[0166] PEBA 4: PA11 (6000 g / mol) and PTMG (650 g / mol) block copolymer with 9.8% PTMG, with a number molar mass of 46,000 g / mol.

[0167] PEBA 5: PA6 (Mn=1500 g / mol) and PEG (1500 g / mol) block copolymer with 50% PEG, with a number molar mass of 55,000 g / mol.

[0168] PEBA 6: PA11 block copolymer (Mn=1000 g / mol) and PTMG (1 OOOg / mol) with 50% PTMG, with a number molar mass of 45,000 g / mol.

[0169] PEBA 7: PA12 (850 g / mol) and PTMG (2000 g / mol) block copolymer with 70.2% PTMG, number molar mass of 5000 g / mol.

[0170] PEBA 8: PA12 (850 g / mol) and PTMG (2000 g / mol) block copolymer with 70.2% PTMG, number molar mass of 800000g / mol.

[0171] TPU1: Elastollan 1185A thermoplastic aromatic polyether-urethane commercially available from BASF.

[0172] PB: Europrene® NEOCIS BR 60 polybutadiene sold by Eni Versalis.

[0173] Compositions EI3 and EI4 were manufactured by molten-state mixing (compounding) in a twin-screw extruder.

[0174] [Table 1]: Thermoplastic elastomer compositions for soles (in % in weight) EU EI2 EI3 EI4 EI5 EC1 EC2 EC3 EC4 EC5 PEBA 1 100 - - - - - - - - - PEBA 2 - 100 - - - - - - - - PEBA 3 - - 60 70 - - - - - - PEBA 4 - - - - - 100 - - - - PEBA 5 - - - - - - 100 - - - PEBA 6 - - - - 100 - - - - 100 PEBA 7 - - - - - - - 100 - - PEBA 8 - - - - - - - - 100 - TPU 1 - - 30 25 - - - - - - PB - - 10 5 - - - - - - Total 100 100 100 100 100 100 100 100 100 100

[0175] For the purpose of evaluating the different compositions, plates of 100mm x 100mm x 100mm and 100mm x 100mm x 2mm, blocks of a diameter of 16mm and a thickness of 6mm and type IA pull-up dumbbells were prepared by injection using a Battenfeld BA800 CDC press with unpolished molds.

[0176] After drying the granules in a desiccator at 70°C for a minimum of 4 hours, they were injected under the following conditions (for examples EI5, EC1 and EC2): - Barrel temperature: 220-240°C - Nozzle temperature: 240°C - Mold temperature: 30°C - Cycle time 60 seconds.

[0177] The injection was carried out under slightly different conditions for examples EU to EI4 and EC3 to EC4: - Sheath temperature: 180-200°C - Nozzle temperature: 200°C - Mold temperature: 30°C - Cycle time 60 seconds.

[0178] The composition of example EC4 was difficult to inject; the resulting incomplete specimens did not allow for the evaluation of elongation at break. The molar mass of PEBA is therefore advantageously adapted to ensure that the composition has sufficient fluidity to allow the injection of thin parts over a long injection length.

[0179] The test specimens obtained with the other compositions were then evaluated in terms of hardness, density, elongation at break, water absorption, abrasion resistance and slip resistance as explained below. (a) Hardness

[0180] Shore A hardness is measured according to ISO 48-4:2008 using a durometer at 23°C. The results are summarized in Table 2 below. (b) Density

[0181] The density of an injected part is measured according to ISO 1183-1 by vertical push in water at 23°C using a Sartorius AC 210P hydrostatic balance equipped with a YDK 01 density kit. The results are summarized in Table 2 below. (c) Elongation at break in tension

[0182] The elongation at break is measured by tensile test according to ISO 527 on dumbbell-type specimens IA at a test speed of 50 mm / min after conditioning the specimens for 14 days at 23°C and in an atmosphere with a relative humidity of 50%. The results are summarized in Table 2 below, (d) Water absorption

[0183] The measurement is carried out on the 100 x 00 x 1 mm plate according to ISO 62:2008 (<5%) after immersion in water at 23°C until equilibrium is reached. Absorption is expressed as a percentage of the difference in mass before and after exposure to water relative to the initial mass. The results are summarized in Table 2 below, (e) Slip resistance

[0184] The dynamic friction coefficient is measured on 100 mm x 00 mm x 2 mm plates according to the SATRA TM 144 evaluation method on a wet STM 603AC quarry tile standard coating at 23°C, using SATRA STM 603 measuring equipment. The sliding resistance is expressed as a coefficient of friction. The higher this coefficient, the higher the sliding resistance. The results are summarized in Table 2 below. (0 Abrasion resistance

[0185] The abrasion resistance of the compositions is measured according to DIN ISO 4649:2017 (method B with rotating test specimen holder) on the injected pads with a diameter of 16 mm and a thickness of 6 mm. Abrasion resistance is expressed as the volume change before and after the test. A composition is considered satisfactory when the volume change is less than 100 mm³. The results are summarized in Table 2 below.

[0186] [Table 2]: Properties of the thermoplastic elastomer compositions studied eu EI2 EI3 EI4 EI5 EC1 EC2 EC3 EC4 EC5 Shore Hardness 89A 83A 74A 76A 94A >100 A 94A ND ND 50A Density 1.02 1.02 1.04 1.04 1.03 1.03 1.14 1.03 ND 0.3 Elongation at break [%] 800 800 650 700 600 400 <50 <50 ND* ND Water absorption [%] 1.3 1.2 1.5 1.5 1.4 1.5 >50 ND ND ND Dynamic friction coefficient 0.33 0.33 0.21 0.2 0.2 0.1 NDND ND ND AV after a brion [m m3] 60 83 70 67 38 <30 ND ND ND 300 * Injection impossible

[0188] The results highlight that the compositions of the soles of the invention present an excellent compromise of properties in terms of resistance to slipping and abrasion, combined with good mechanical properties, in particular elongation at break, low water absorption and moderate hardness.

[0189] The sole compositions of the invention thus exhibit better slip resistance compared to compositions comprising a PEBA with a low content of polyether blocks with 3 or more carbon atoms per oxygen atom (comparative example EC1). They exhibit lower water absorption and therefore better dimensional and density stability compared to PEBAs with PEG polyether blocks (comparative example EC2). Furthermore, the molar mass is appropriate to ensure good mechanical properties, for example, elongation at break (comparative example EC3), while limiting viscosity to allow the injection of thin parts (comparative example EC4). Finally, the density of the composition is important to ensure good abrasion resistance (comparative example EC5). List of documents cited

[0190] WO 2021 / 101970 Al

Claims

Demands

1. Shoe sole, in particular outsole, made of a composition comprising, by weight relative to the total weight of the composition: a. 50 to 100% of at least one polyether block amide (PEBA) comprising polyamide blocks and polyether blocks, comprising on average more than 50% polyether blocks, wherein the polyether blocks comprise on average more than 50% ether motifs having at least 3 carbon atoms per oxygen atom; b. 0 to 50%, preferably 5 to 40% and in particular 10 to 30% fillers; and c. 0 to 5%, preferably 0.1 to 4% and in particular 1 to 3% of additives, wherein the composition has a Shore hardness of less than 100A and a density greater than 0.85, and wherein the PEBA has a number-average molar mass Mn as measured by size exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol.

2. Sole according to claim 1, wherein the composition further comprises (d) 0 to 40%, preferably 5 to 30% and in particular 10 to 20% by weight of polymer different from (a).

3. Sole according to claim 1 or 2, wherein the composition further comprises (e) 0 to 20%, preferably 2 to 15% and in particular 5 to 10% by weight of rubber.

4. Sole according to any one of claims 1 to 3, wherein PEBA comprises 50 to 90%, in particular 55 to 85% and especially 60 to 80% by weight of polyether blocks.

5. Sole according to any one of claims 1 to 4, wherein the polyether blocks comprise on average more than 50% by weight of polytetrahydrofuran (PTMG) motifs.

6. Sole according to any one of claims 1 to 5, wherein the PEBA comprises polyamide blocks having 9 or more carbon atoms per amide group, in particular selected from PA10, PAU, PA12, PA513, PA514, PA516, PA518, PA536, PA612, PA613, PA614, PA616, PA618, PA636, PA912, PA104, PA109, PA1010, PA1012, PA1013, PA1014, PA1016, PA1018, PA1036, PA129, PA1210, PA1212, PA1213, PA1214, PA1216, PA1218, PA1236, PA12T, and their copolymers.

7. Sole according to any one of claims 1 to 6, wherein PEBA comprises 10 to 50%, in particular 15 to 45% and especially 20 to 40% by weight of polyamide blocks.

8. Sole according to any one of claims 1 to 7, wherein the PEBA has a ratio between the number-average molar mass of the polyamide blocks and the number-average molar mass of the polyether blocks of 0.1 to 3.0, preferably from 0.2 to 2.0 and in particular from 0.3 to 1.

0.

9. A method for manufacturing a sole according to any one of claims 1 to 8, comprising the steps of: (i) Mixing in a molten state, by weight relative to the total weight of the composition: a. 50 to 100% of at least one polyether block amide (PEBA) comprising polyamide blocks and polyether blocks, comprising on average more than 50% polyether blocks, wherein the polyether blocks comprise on average more than 50% ether motifs having at least 3 carbon atoms per oxygen atom; b. 0 to 50% fillers; and c. 0 to 5% of additives, wherein the composition has a Shore hardness of less than 100A and a density greater than 0.85, wherein PEBA has a number-average molar mass Mn as measured by size-exclusion chromatography according to ISO 16014-1:2019 of between 10,000 and 70,000 g / mol; and (ii) shape the resulting composition to form a sole.

10. A manufacturing method according to claim 9, wherein step (ii) is carried out by injection.

11. Use of a sole according to any one of claims 1 to 8 for the manufacture of a shoe.

12. Footwear, in particular sports footwear, comprising a sole according to any one of claims 1 to 8.

13. Footwear according to claim 12, characterized in that it is dress footwear, for example sneakers, sandals, boots or ankle boots; sports footwear, in particular walking shoes, hiking, athletics, running; team sports shoes, especially indoor shoes, for example football, handball, basketball, or volleyball; tennis shoes, table tennis shoes, badminton shoes, skateboard shoes; ski boots or safety shoes.

14. Method of manufacturing a shoe according to claim 12 or 13, comprising the steps of: I. assembling a sole according to one of claims 1 to 8 with a shoe upper, in particular by gluing, heat gluing or overmolding.

15. A method for recycling a shoe according to claim 12 or 13, comprising the steps of: (1) separating the sole from the shoe, if applicable; (2) grinding the sole to obtain a ground material; (3) heating the ground material obtained in step (2) until melted to obtain a molten mass; and (4) extruding the molten mass obtained in step (3) to obtain granules.