Flexible composition with improved slip resistance

Abstract

The invention relates principally to a polymer composition comprising: (a) 55 to 99%, preferably 60 to 95%, advantageously 65 to 90%, and in particular 70 to 85% by weight of polyether block amide (PEBA) having a number-average molar mass ratio of polyamide blocks to polyether blocks less than or equal to 1.0; (b) 1 to 45% by weight of a modifier selected from: i. a thermoplastic elastomer in the form of a block copolymer with a number-average molar mass ratio D of rigid blocks to flexible blocks less than 0.8; ii. a rubber, raw or crosslinked; (c) 0 to 5% by weight of additives; and (d) 0 to 5% by weight of fillers, the sum of the percentages of components (a) to (d) adding up to 100%, and in which the composition comprises less than 4% by weight of carbon black.

Description

Title of the invention: Flexible composition with improved slip resistance technical field

[0001] This patent application relates to flexible compositions based on elastomers with improved slip resistance, their manufacturing process, articles comprising these compositions and the use of these compositions in particular for the manufacture of soles for sports shoes. Previous technique

[0002] Thermoplastic elastomers (TPE) are widely used, for example in the field of sports equipment, in particular for the manufacture of soles or sole components of sports shoes.

[0003] In these applications, materials with a specific property profile are sought, including good elastic recovery ensuring good responsiveness, low density, low dissipation factor (tan delta), high tensile elongation at break, low tensile residual deformation and good ability to withstand repeated impacts and return to the initial shape.

[0004] In order to improve the safety and durability of footwear, materials combining high slip resistance on wet surfaces with high abrasion resistance are also sought. Furthermore, it is desirable that the material not leave marks on the floor and retain an attractive appearance after abrasion. To be compatible with most footwear manufacturing processes, these materials are also required to exhibit good overmolding and injection molding properties.

[0005] US patent application 2015 / 0267045 A1 describes lightweight composite materials comprising rubber, a polymer, in particular thermoplastic polyurethane (TPU) or polymethacrylate, and one or more fillers or additives. Their manufacture requires several steps and a prolonged time.

[0006] Patent application WO 2016 / 033273 Al describes shoe soles with improved slip resistance by promoting the removal of wet soil accumulated outside a profiled sole, the sole having on its outer surface a polymeric layer capable of absorbing water, which is expelled under compression and removes the soil from the interface.

[0007] Composites obtained by dynamic vulcanization of a functionalized and vulcanizable elastomer during its mixing with a polyether or polyester block-sequenced copolymer are also known from patent application EP 0 656 388 Al amorphous in the presence of a vulcanization system. These composites are considered, among other things, as wear layers or abrasion-resistant and slip-resistant cleats for polyetheresteramide soles of footwear. These compositions are obtained by a process that exhibits low productivity and is batch-based.

[0008] Patent application WO 2023 / 118761 describes compositions comprising a PEBA and a cross-linked rubber powder. These compositions exhibit good elastic recovery, low density, and good anti-slip properties. However, these compositions tend to leave marks on the floor when subjected to abrasion. Furthermore, their elongation at break and injection properties are generally insufficient for use as athletic shoe soles.

[0009] Patent application WO 2023 / 118760 describes compositions comprising a thermoplastic elastomer and a cross-linked rubber powder. These compositions exhibit good anti-slip properties, but also tend to mark the floor when subjected to abrasion. Summary of the invention

[0010] The invention therefore aims to provide a composition that meets all these requirements, and in particular exhibits resistance to abrasion and slippage, with a high coefficient of friction on wet surfaces. The invention also aims to provide a composition that leaves little or no marks on the floor.

[0011] The invention therefore aims to provide a polymer composition comprising:

[0012] (a) 55 to 99%, preferably 60 to 95%, advantageously 65 to 90%, and in particular 70 to 85% by weight of polyether block amide (PEBA) having a number average molar mass ratio of polyamide blocks and polyether blocks less than or equal to 1.0, preferably less than 0.8;

[0013] (b) 1 to 45%, preferably 5 to 40%, advantageously 10 to 35%, and in particular 15 to 30% by weight of a modifier chosen from:

[0014] (i) a thermoplastic elastomer in the form of a block copolymer with a ratio D of the number-average molar mass of the rigid blocks and the flexible blocks less than 0.8, preferably less than 0.7, and advantageously less than 0.5; and

[0015] (ii) a raw or crosslinked rubber; and

[0016] (c) 0 to 5%, preferably 0.1 to 4%, in particular 1 to 2% by weight of additives; and

[0017] (d) 0 to 5%, preferably 0.5 to 3% by weight of fillers,

[0018] the sum of the percentages by weight of components (a) to (d) adding to 100%,

[0019] wherein the composition comprises less than 4%, preferably less than 2%, and advantageously less than 1% by weight of carbon black.

[0020] According to a preferred embodiment, the composition has a Shore hardness of 10A to 100A, preferably from 20A to 90A, and in particular from 40A to 85A.

[0021] Preferably, the PEBA comprises polyamide blocks selected from the group consisting of PA 6, 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 or their copolymers.

[0022] In particular, PEBA may include polyether blocks selected from the group consisting of PEG (polyethylene glycol) blocks, PPG (propylene glycol) blocks, PO3G (polytrimethylene glycol) blocks and PTMG (polytetramethylene glycol) blocks.

[0023] Preferably, the PEBA comprises PA 11 and PTMG blocks or PA 12 and PTMG blocks.

[0024] According to one embodiment, when the modifier is a thermoplastic elastomer, it is chosen from thermoplastic polyurethanes (TPU) and styrene copolymers.

[0025] According to another embodiment, when the modifier is a rubber, it is chosen from the group consisting of polyisoprene rubber, ethylene-propylene-diene rubber (EPDM), nitrile rubber (NBR), polybutadiene rubber, styrene-butadiene rubber (SBR), butyl rubber (isobutylene-isoprene) and one of their mixtures.

[0026] Advantageously, when the modifier is a rubber, it is dispersed in the composition in the form of nodules of average diameter in a number of less than 850 pm, preferably less than 800 pm, advantageously less than 750 pm.

[0027] According to a second aspect, the invention relates to a method for manufacturing the composition according to the invention, comprising the steps of:

[0028] (i) mix in the molten state, preferably in a twin-screw extruder or in a co mixer:

[0029] (a) 55 to 99% by weight of polyether block amide (PEBA) having a ratio of the number average molar mass of polyamide blocks and polyether blocks less than or equal to 1.0;

[0030] (b) 1 to 45% by weight of a modifier selected from:

[0031] i. a thermoplastic elastomer in the form of a block copolymer with a number-average molar mass ratio D of rigid blocks to flexible blocks of less than 0.8; and

[0032] ii. a rubber, raw or cross-linked;

[0033] (c) 0 to 5% by weight of additives; and

[0034] (d) 0 to 5% by weight of charges;

[0035] the sum of the percentages by weight of components (a) to (d) adding up to 100%,

[0036] wherein the composition comprises less than 4% carbon black,

[0037] (ii) optionally, shape the mixture into granules, filaments or powder; and

[0038] (iii) retrieve the obtained composition.

[0039] According to a third aspect, the invention aims at the use of the composition according to the invention for the manufacture of an article selected from the group consisting of shoe components, sports equipment parts, treadmills, aquatic equipment, eyeglass frame parts, ski mask frames, vibration isolation parts in electronics and on machines, external battery cases, automotive parts and wheel treads.

[0040] Preferably, the composition is used for the manufacture of an outsole or an outsole.

[0041] According to a fourth aspect, the invention relates to a method of manufacturing an article implementing the composition according to the invention.

[0042] According to a fifth aspect, the invention relates to an article comprising the composition according to the invention selected from the group consisting of shoe components, sports equipment parts, treadmills, aquatic equipment, eyeglass frame parts, ski mask frames, vibration isolation parts in electronics and on machines, external battery cases, automotive parts and wheel treads.

[0043] Advantageously, this is a wear sole or an outsole.

[0044] According to a sixth aspect, the invention relates to a method for recycling an article according to the invention, comprising the following successive steps: i. recovery, after possible separation, of at least a part of said article in thermoplastic material comprising a composition according to the invention; ii. grinding the thermoplastic material to obtain particles, iii. melting the particles to obtain a molten mixture, and iv. optionally, adding other components to the molten mixture, and v. optionally, forming granules, filaments or powders from the molten mixture obtained at the end of step iii) or iv), and vi. Optionally, shaping of granules, filaments or powders. Brief description of the drawings

[0045] The invention will be better understood with regard to the following description and the figures, which show:

[0046] [Fig-1]: Appearance of the composition according to the comparison example EC1 after the test abrasion resistance according to DIN ISO 4649:2017; and

[0047] [Fig.2]: appearance of the composition according to the example according to the EU invention after the abrasion resistance test according to DIN ISO 4649:2017. Description of implementation methods Definition of terms

[0048] Throughout the description, the terms listed below have the following meanings.

[0049] The term "polymer composition" refers to a macroscopically homogeneous composition comprising several polymers in a mixture. The term also encompasses compositions composed of immiscible phases dispersed on a micrometer scale. For example, rubber may be present in the composition in dispersed form, for example, as nodules. However, the number-average diameter of the dispersed phase particles or nodules is advantageously less than 850 pm, preferably less than 800 pm, and particularly less than 750 pm. Advantageously, the number-average diameter of the nodules is greater than 1 pm, advantageously greater than 5 pm, and particularly greater than 20 pm.

[0050] The number-average diameter of the nodules in the composition can be measured by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). SEM has a large field of view and allows observation at magnifications up to x5000. For observing subnanometer particles, the use of TEM is preferable. Preferably, a molded sample is observed by SEM, providing an overview, followed by more precise observation by TEM to observe the smallest nodules according to the following protocol:

[0051] (i) Obtaining a smooth surface: cold microtome surfacing with a knife diamond;

[0052] (ii) Labeling of one of the two phases: depending on the chemical composition, either labeling of the dispersed phase with a 2% aqueous solution of osmium tetroxide or ruthenium tetroxide by immersion or vapor, for a time to be defined from a few seconds to a few minutes, depending on the observation technique used; or labeling of the matrix with phosphotungstic acid (2%) for a time to be defined from a few seconds to a few minutes depending on the observation technique used;

[0053] (iii) Observation of the morphology by SEM with the appropriate magnification to observe both the continuous and dispersed phases of the composition, the dispersed phase having at least 200 nodules; and

[0054] (iv) Observation of the morphology by TEM with the appropriate magnification to observe both the continuous and dispersed phases of the composition, the dispersed phase having at least 200 nodules. A maximum magnification of 2,000x is generally used;

[0055] (v) Analysis of images obtained by SEM and TEM with ImageJ type software:

[0056] 1. Segmentation of the dispersed phase; and

[0057] 2. Analysis of the size distribution of the nodules and calculation of the average number, in volume of equivalent circle diameters, standard deviation and distribution histogram on each image.

[0058] (vi) Calculation of the average of the equivalent number diameters obtained on the SEM image and the TEM image to obtain the average number diameter of the nodules in the composition

[0059] The term “PEBA” refers to a sequenced copolymer comprising polyamide blocks and polyether blocks.

[0060] The term "polyamide" or "PA" refers throughout to a homopolyamide or copolyamide, that is, the products of the condensation of polyamide monomers, in particular lactams, α,co-aminocarboxylic acids and / or dicarboxylic acids and diamines. 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).

[0061] The term "modifying" is meant to designate a thermoplastic or thermosetting elastomer which has the effect of modifying the properties of the matrix, formed here mainly by a PEBA.

[0062] The term "thermoplastic elastomer" or "TPE" 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. For the purposes of this discussion, PEBAs are explicitly excluded from this definition of TPEs.

[0063] The term "rubber" refers to a thermosetting elastomer. The term encompasses both crosslinkable but not yet crosslinked rubbers, also called "raw rubber" or "unrefined rubber", and crosslinked rubbers, in which the molecular chains are linked by bridges forming a three-dimensional network.

[0064] The term "copolymer" refers to a polymer resulting from the copolymerization of at least two types of chemically different monomers, called comonomers. A copolymer is therefore formed of at least two repeating units. It may also be formed of three or more repeating units.

[0065] By "alloy", we mean a homogeneous mixture (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.

[0066] In what follows, physical quantities are, unless otherwise stated, measured under normal temperature and pressure conditions, specifically 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 as including each of the limits mentioned. Finally, unless otherwise stated, percentages are expressed by weight relative to the total weight of the composition. PEBA

[0067] The composition according to the invention therefore comprises, as a major component, a particular polyether block amide (PEBA).

[0068] PEBAs result from the polycondensation of reactive-end polyamide blocks (rigid blocks) with reactive ends and reactive-end polyether blocks (flexible blocks). In particular, PEBAs can result from the polycondensation of: a. polyamide blocks with diamine ends with polyoxyalkylene blocks with dicarboxylic ends; or of b. polyamide blocks with dicarboxylic ends with polyetherdiols (polyoxyalkylene α,co-dihydroxylated blocks), the products obtained in this case being polyetheresteramides.

[0069] Preferably, 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.

[0070] The polyether blocks essentially comprise or are made up of alkylene oxide motifs.

[0071] These may include PEG (polyethylene glycol) blocks made up of ethylene oxide motifs, PPG (propylene glycol) blocks made up of propylene oxide motifs, PO3G (trimethylene ether glycol) blocks, PTMG (polytetramethylene glycol) blocks made up of tetrahydrofuran motifs, with PTMG blocks being preferred.

[0072] PEBAs may include in their chain several distinct types of polyethers, the copolyethers being block or statistical.

[0073] 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.

[0074] 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.

[0075] Three types of polyamide blocks can be used advantageously.

[0076] 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.

[0077] The dicarboxylic acid may be, in particular, an aliphatic, cycloaliphatic or aromatic dicarboxylic acid. By way of example, butanedioic acid, adipic acid, azelaic acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, brassylic acid, thapsic acid, octadecanedicarboxylic acid, 1,4-cyclohexyldicarboxylic acid, terephthalic acid, isophthalic acid and dimerized fatty acids may be mentioned.

[0078] 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.

[0079] The diamine may be, in particular, an aliphatic, cycloaliphatic or aromatic diamine. By way of examples, 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).

[0080] 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.

[0081] 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.

[0082] Examples of α,co-amino carboxylic acids include aminocaproic, amino-7-heptanoic, amino-10-decanoic, amino-11-undecanoic and amino-12-dodecanoic acids.

[0083] The lactams are preferably chosen from those which preferably comprise 6 to 12 carbon atoms, in particular caprolactam, oenantholactam and lauryllactam.

[0084] Advantageously, the polyamide blocks of the second type are chosen from the PA 6, PA 10, PA 11 and PA 12 blocks.

[0085] 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.

[0086] Examples of third-type polyamide blocks include PA 66 / 6 and PA 66 / 610 / 11 / 12.

[0087] Advantageously, the PEBA comprises polyamide blocks chosen from 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 10, PA 104, PA 109, PA 1010, PA 1012, PA 1013, PA 1014, PA 1016, PA 1018, PA 1036, PA 10T, PA 11, PA 12, PA 124, PA 129, PA 1210, PA 1212, PA 1213, PA 1214, PA 1216, PA 1218, PA 1236, PA 12T, and their copolymers.

[0088] 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.

[0089] 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.

[0090] PEBAs can be obtained in particular by copolycondensation of polyetherdiol with polyamide blocks having carboxylic ends. The general two-step method for preparing PEBA copolymers having ester bonds between the PA blocks and PE blocks is described, for example, in document FR 2846332. The general method for preparing PEBA copolymers having amide linkages between PA blocks and PE blocks is described, for example, in document EP 1482011. 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).

[0091] PEBA may include, in addition to polyamide and polyether blocks, other additional blocks.

[0092] For example, the 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 PEG block and a PTMG block. The PEBA triblock is preferably a copolyetheresteramide.

[0093] The number-average molar mass (Mn) of the polyamide blocks in 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 PEBA is less than 2,000 g / mol, and in particular less than 1,000 g / mol. In embodiments, the number-average molar mass of polyamide blocks in 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.

[0094] 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.

[0095] The number-average molar mass of Mn can be adjusted by the chain-limiting agent content. It can be calculated according to the following relationship:

[0096] [Math.l] M ■ vW -.....— / tv - > , - + MWr ■ s > * *■*•*&■ «-faosoww avvt ^massif duiw ~ *»xvv

[0097] In this formula, nmonomer represents the number of moles of monomer, ni chain imitator represents the number of moles of excess diacid limiter, MWrepeater represents the molar mass of the repeating motif, and MWichain imitator represents the molar mass of the excess diacid.

[0098] 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.

[0099] According to the invention, the ratio of the number-average molar mass of the polyamide blocks and the polyether blocks in the PEBA is less than or equal to 1.0, in particular less than 0.9, and in particular less than 0.8. 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.

[0100] Advantageously, the ratio of the number-average molar mass of the polyamide blocks to that of the polyether blocks of the PEBA is from 0.1 to 1.0, preferably from 0.2 to 0.9 and in particular from 0.3 to 0.8. In particular, the ratio can be from 0.1 to 0.2, or from 0.2 to 0.3, or from 0.3 to 0.4, or from 0.4 to 0.5, or from 0.5 to 0.6, or from 0.6 to 0.7, or from 0.7 to 0.8, or from 0.8 to 0.9, or from 0.9 to 1.0.

[0101] Indeed, when this ratio is too high, the material is too rigid, resulting in poor slip resistance on smooth and wet surfaces, and also 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, thus reducing the lifespan of the shoe.

[0102] The PEBA in the composition preferably 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.

[0103] 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®. Modifiers

[0104] The composition according to the invention further comprises, as a minor component, a modifier, which may be either a specific thermoplastic elastomer or a rubber.

[0105] More specifically, it comprises from 1 to 45%, preferably from 5 to 40%, advantageously from 10 to 35%, and most particularly 15 to 30% by weight of such a modifier.

[0106] According to a first embodiment, the modifier is a thermoplastic elastomer in the form of a block copolymer with a number-average molar mass ratio D of the rigid blocks and the flexible blocks less than 0.8, preferably less than 0.7 and advantageously less than 0.5.

[0107] Preferably, the thermoplastic elastomer comprises rigid blocks of motifs selected from polyurethanes, polystyrene, and polyesters. Preferably, the thermoplastic elastomer comprises flexible blocks of motifs selected from polyols. The flexible and rigid blocks of the thermoplastic elastomer are advantageously covalently linked by functional groups selected from C-C bonds, esters, methanes, and ureas.

[0108] Preferably, the thermoplastic elastomer is chosen from thermoplastic polyurethanes, styrene copolymers and polyester elastomers, preferably from thermoplastic polyurethanes and styrene copolymers.

[0109] Advantageously, the thermoplastic elastomer has a tensile modulus, as measured according to ISO 527, of between 5 and 800 MPa, preferably between 10 and 300 MPa, and more preferably between 20 and 150 MPa. The tensile modulus can be controlled, in particular, by means of the number-average molar mass ratio of rigid blocks to flexible blocks in the elastomer.

[0110] According to one embodiment, the thermoplastic elastomer also has a Shore hardness between 10A and 90A, in particular between 20A and 80A. Thermoplastic polyurethanes

[0111] The modifying element in the composition of the invention may be, in particular, a thermoplastic polyurethane (TPU).

[0112] Thermoplastic polyurethane is a rigid block and flexible block copolymer. 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.

[0113] 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.

[0114] The polyisocyanate may be aliphatic, cycloaliphatic, araliphatic and / or aromatic. Preferably, the polyisocyanate is a diisocyanate.

[0115] Advantageously, the polyisocyanate is selected from the group consisting of tri-, tetra-, penta-, hexa-, hepta- and / or octamethylene diisocyanate, 2-methylpentamethylene 1,5-diisocyanate, 2-ethylbutylene-1,4-diisocyanate, 1,5-pentamethylene diisocyanate, 1,4-butylene diisocyanate, l-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 1,4-bis(isocyanatomethyl)cyclohexane, l,3-bis(isocyanatomethyl)cyclohexane (HXDI), 2,4-paraphenylene diisocyanate (PPDI), 2,4-tetramethylenexylene 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 düsocyanate, 2,2'-, 2,4'- and / or 4,4'-diphenylmethane düsocyanate (MDI), 1,5-naphthylene düsocyanate (NDI), 2,4- and / or 2,6-toluene düsocyanate (TDI), diphenylmethane düsocyanate, 3,3'-dimethyl-diphenyl düsocyanate, 1,2-diphenylethane düsocyanate, phenylene düsocyanate, methylene bis (4-cyclohexylisocyanate) (HMDI) and mixtures thereof.

[0116] More preferably, the polyisocyanate is chosen from the group consisting of diphenylmethane diisocyanates (MDI), toluene diisocyanates (TDI), pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), methylene bis (4-cyclohexyüsocyanate) (HMDI) and mixtures thereof.

[0117] Even more preferably, the polyisocyanate is 4,4'-MDI (4,4'-diphenylmethane dusocyanate), 1,6-HDI (1,6-hexamethylene dusocyanate), or a mixture thereof. Advantageously, it does not comprise cycloaliphatic dusocyanate.

[0118] Preferably, the polyisocyanate is aliphatic.

[0119] 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.

[0120] Advantageously, the compound that reacts with the isocyanate has at least one reactive group selected from 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.

[0121] 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.

[0122] 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, so 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 polyurethanes are polyether blocks and / or polyester blocks (the polyol being a polyether polyol and / or a polyester polyol).

[0123] 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.

[0124] 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.

[0125] 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.

[0126] The polyether polyol is preferably a polytetrahydrofuran (flexible blocks of thermoplastic polyurethane therefore being blocks of polytetrahydrofuran) and / or a polypropylene glycol (flexible blocks of thermoplastic polyurethane therefore being blocks of polypropylene glycol) and / or a polyethylene glycol (flexible blocks of thermoplastic polyurethane therefore being blocks of polyethylene glycol), preferably a polytetrahydrofuran having a number-average molar mass of 500 to 15,000 g / mol, preferably of 1,000 to 3,000 g / mol. The polyether polyol may be a polyetherdiol, which is the reaction product of ethylene oxide and propylene oxide; the molar ratio of ethylene oxide to propylene oxide is preferably 0.01 to 100, more preferably 0.1 to 9, more preferably 0.25 to 4, more preferably 0.4 to 2.5, more preferably 0.6 to 1.5 and it is more preferably 1.

[0127] The polyalkylene diols usable in the invention are preferably butadiene-based.

[0128] One or more polyols may be used as a reactive compound with the isocyanate.

[0129] In a particularly preferred manner, the flexible blocks of the TPU are blocks of polytetrahydrofuran, polypropylene glycol and / or polyethylene glycol.

[0130] 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.

[0131] The chain extender may be aliphatic, araliphatic, aromatic and / or cycloaliphatic.

[0132] 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").

[0133] A single chain extender or a mixture of at least two chain extenders can be used.

[0134] 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.

[0135] 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.

[0136] Advantageously, the TPU can be recycled TPU and / or partially or completely bio-based TPU.

[0137] 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.

[0138] The ratio of the number-average molar mass of the rigid polyurethane blocks to 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 a method of In practice, this ratio is 0.1 to 1.0, preferably 0.2 to 0.8 and in particular 0.3 to 0.5.

[0139] According to one embodiment, PEBA forms an alloy with TPU during mixing.

[0140] 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. Styrene copolymers

[0141] The modifier in the composition of the invention may also be a styrene copolymer.

[0142] In the broadest sense, a styrene copolymer is a copolymer comprising at least one repeating unit containing styrene. However, generally, the styrene copolymer used in the composition of the invention comprises up to 50% by weight, preferably up to 45%, and advantageously up to 40% by weight of styrene.

[0143] This copolymer can be selected from conjugated styrene and alpha-olefin or diene copolymers, such as ethylene, propylene, 1-butene, 1-octene, butadiene, or isoprene. By way of example, the following block copolymers may be mentioned: styrene / ethylene-butene / styrene (SEBS), styrene-ethylene-propylene (SEP), styrene / ethylene-propylene / styrene (SEPS), styrene / isoprene / butadiene / styrene (SIBS), styrene / butadiene / styrene (SBS), and styrene / isoprene / styrene (SIS). The styrene / ethylene-butene / styrene (SEBS) and styrene-ethylene-propylene (SEP) block copolymers are particularly preferred.

[0144] The styrene copolymer is obtained by sequenced copolymerization. The copolymer may also have a linear or branched structure, a linear structure being preferred.

[0145] The ratio of the number average molar mass of rigid polystyrene blocks and flexible blocks, for example conjugated alpha-olefins or dienes, 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 ratio is from 0.1 to 1.0, preferably from 0.2 to 0.8 and in particular from 0.3 to 0.5.

[0146] The styrene copolymer can also be hydrogenated. Preferably, it is hydrogenated.

[0147] The styrene copolymer may be functionalized, non-functionalized, or partially functionalized. A functionalized copolymer may be obtained by copolymerization with a comonomer comprising reactive motifs, in particular acid, anhydride, or epoxy functions.

[0148] The styrene copolymer can also be grafted, in particular by reacting the copolymer with a reagent such as an unsaturated epoxide like glycidyl methacrylate, an unsaturated carboxylic acid like (meth)acrylic acid, possibly partially or totally neutralized, or an unsaturated carboxylic acid anhydride like maleic anhydride, maleic anhydride and glycidyl methacrylate being preferred. A grafted styrene copolymer preferably has a grafting ratio of 0.01 to 5%, in particular 0.1 to 3% and in particular 0.5 to 2% by weight.

[0149] The styrene / ethylene-butene / maleic anhydride grafted block copolymer (SEBS-g-MAH) and the glycidyl methacrylate grafted block copolymer (SEBS-g-GMA) are particularly preferred.

[0150] Preferably the styrene copolymer comprises less than 5%, advantageously less than 1% by weight of oil. Rubber

[0151] According to a second embodiment, the modifier in the composition of the invention is a rubber.

[0152] The rubber may, in particular, be raw, uncrosslinked rubber, or rubber that is at least partially crosslinked. The rubber may come from a wide variety of sources.

[0153] Rubber may in particular be natural or synthetic rubber or a mixture of these.

[0154] Natural rubber may in particular be selected from cis-1,4-polyisoprene and / or trans-1,4-polyisoprene.

[0155] Synthetic rubber may in particular be selected from the group consisting of bromobutyl rubber, butyl rubber, polyisoprene rubber, polynorbornene 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. Among these, polyisoprene rubber, ethylene-propylene-diene rubber (EPDM), nitrile rubber (NBR), polybutadiene rubber, styrene-butadiene rubber (SBR), butyl rubber (isobutylene-isoprene) and their mixtures are particularly preferred.

[0156] As an example of a rubber mixture, one can cite a mixture of natural rubber and polybutadiene rubber and a mixture of natural rubber and styrene-butadiene rubber.

[0157] Advantageously, the rubber contains less than 5%, preferably less than 2% by weight of carboxylated nitrile rubber (XNBR). Advantageously, the rubber is not functionalized.

[0158] Alternatively, it may be a rubber comprising a branched nitrile rubber (NBR) and a pre-crosslinked branched nitrile rubber (NBR), such as the products in the Chemigum powder range marketed by Synthomer, United Kingdom, or a rubber comprising a pre-crosslinked acrylate terpolymer, such as the products in the Sunigum powder range marketed by the same company.

[0159] According to one embodiment, the rubber is recycled rubber.

[0160] Preferably, the rubber is in powder form. It may be particularly ground cross-linked rubber. The powder preferably has a median volume diameter (Dv50) between 2 and 1000 µm, especially less than 850 µm, even more preferably less than 800 µm, and especially less than 750 µm. Dv50 corresponds to the particle size value that divides the particle volume exactly in half. A low Dv50 value improves the suitability for injection molding thin parts. Dv50 is measured according to ISO 13320:2020, using a Malvem Insitec laser particle size analyzer and RTSizer software. Rubber in powder form can be prepared using various methods. For example, rubber can be obtained by a grinding process. Various grinding processes exist such as, for example, mechanical grinding at room temperature, cryogenic grinding, grinding using water jets, or powder micronization.

[0161] According to another embodiment, a raw rubber can be used which is crosslinked in situ during the mixing process, in particular the compounding step. Additives

[0162] The composition of the invention further comprises 0 to 5% by weight, preferably 0.1 to 2% by weight of additives relative to the total weight of the composition.

[0163] 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.

[0164] According to a preferred embodiment, the composition comprises 0.05 to 0.2% by weight of one or more antioxidant and / or UV stabilizer agents.

[0165] Crosslinking additives are particularly useful when using raw rubber intended to be crosslinked during the mixing of the composition. Among the abrasion-resistant additives useful for improving abrasion resistance, high or even ultra-high molecular weight polysiloxanes, especially in powder form, and dimethylsilicone in fluid form, can be mentioned in particular.

[0166] Advantageously, the composition contains less than 4%, and in particular less than 2% by weight of copolyolefins containing glycidyl methacrylate. Charges

[0167] According to the invention, the composition also comprises 0 to 5% by weight, preferably 0.5 to 3% by weight of fillers relative to the total weight of the composition.

[0168] 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.

[0169] These fillers are generally in powder form but can also be in other forms, particularly in the form of fibers. Preferably, the composition does not include glass fibers.

[0170] The fillers can be added to the composition separately or through other components, for example rubber. Indeed, rubber, particularly when recycled, can contain up to 50%, in particular 2 to 30%, and especially 3 to 10% by weight of fillers.

[0171] Some rubbers, particularly recycled ones, also contain carbon black. However, a high carbon black content leads to road marking during use. Therefore, the composition contains less than 4% carbon black, specifically less than 2%, and in particular less than 1% by weight. The carbon black content is determined by TGA according to ISO 11358 by performing a dynamic test under nitrogen from 30 to 900°C at 10°C / min, followed by a 10-minute hold at 900°C in air to degrade the carbon derivatives. The quantity of carbon black corresponds to the difference between the residue levels obtained at 900°C under nitrogen and at 900°C after air treatment. A. Composition

[0172] The composition of the invention as described above has a set of interesting properties, particularly in comparison with rubber or TPU compositions.

[0173] Advantageously, the composition is homogeneous when examined with the naked eye, and forms a non-heterogeneous medium, for example non-porous.

[0174] This is preferably a flexible composition, with a Shore hardness as measured according to ISO 48-5:2018, from 10A to 100A, preferably from 20A to 90A, and advantageously from 40A to 85A. The hardness of the composition can be adjusted by choosing the PEBA and the modifier. Thus, the hardness can be decreased, for example, by choosing a softer PEBA and / or modifier. Conversely, the hardness can be increased by choosing a less flexible PEBA and / or modifier.

[0175] Furthermore, the composition exhibits high resistance to abrasion, which is manifested by a volume variation after the test of less than 100 mm3, and in particular less than 90 mm3, advantageously less than 80 mm3.

[0176] The composition also exhibits good resistance to slippage on wet surfaces. Thus, its coefficient of dynamic friction, as measured according to SATRA TM 144, is preferably greater than 0.2, and in particular greater than 0.25, advantageously greater than 0.3.

[0177] Preferably, the composition also produces a low or even zero ground marking, as measured according to the SATRA TM223 standard.

[0178] Similarly, the composition preferably has a damping, expressed by the tan delta, between 0.1 and 0.5, preferably between 0.2 and 0.4. Such a composition makes it possible to ensure both good adhesion to the ground and good responsiveness.

[0179] 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 dynamic mechanical analysis (DMA) 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.

[0180] The composition of the invention is also lighter than rubber and TPU. Generally, its density, as measured according to ISO 1183-1, is less than 1.1.

[0181] Advantageously, the composition of the invention also exhibits an elongation at break, as measured according to ISO 527, greater than 400%, in particular 500%, and especially 600%.

[0182] Furthermore, the composition preferably has a melt flow index (MVI) greater than 5 cm³ / 10 min, in particular greater than 10 cm³ / 10 min, and especially greater than 15 cm³ / 10 min. The melt flow index (MVI) is measured according to the ISO 1133:2011-1 standard at 220°C under a load of 2.16 kg on a material with a moisture content of less than 0.02%.

[0183] Furthermore, the composition of the invention is also more tear-resistant than rubber. Advantageously, it exhibits a tear resistance, as measured according to ISO 34-1:2022, greater than 30 N / mm, preferably greater than 40 N / mm.

[0184] The composition of the invention lends itself easily to injection, and therefore allows in particular the manufacture of thin parts, and to overmolding, a process of interest in particular for the assembly of shoes, in particular of the insole with the outsole.

[0185] According to one embodiment, the composition of the invention does not require vulcanization and therefore allows for faster manufacturing than rubber.

[0186] Finally, the composition of the invention exhibits good recyclability compared to rubber, which does not allow recycling, and TPU, which tends to release isocyanates. B. Manufacturing process for the composition

[0187] According to a second aspect, the invention relates to a method for manufacturing the composition according to the invention, comprising the steps of:

[0188] (a) mix in the molten state, preferably in a twin-screw extruder, or in a co mixer:

[0189] a. 55 to 99% by weight of polyether block amide (PEBA) having a number-average molar mass ratio of polyamide blocks and polyether blocks less than or equal to 1.0;

[0190] b. 1 to 45% by weight of a modifier selected from:

[0191] i. a thermoplastic elastomer in the form of a block copolymer with a number-average molar mass ratio D of rigid blocks to flexible blocks of less than 0.8; and

[0192] ii. a rubber; and

[0193] c. 0 to 5% additives; and

[0194] d. 0 to 5% by weight of charges;

[0195] the sum of the percentages by weight of components (a) to (d) adding up to 100%,

[0196] wherein the composition comprises less than 4% by weight of carbon black,

[0197] (b) optionally, shape the mixture into granules, filaments or powder, and

[0198] (c) retrieve the composition obtained.

[0199] The mixing step of the process can in particular be carried out by applying high shear, for example in an extruder, combined with heating or a irradiation to allow good dispersion of the molten components and thus obtain a homogeneous mixture. C. Use of the composition

[0200] According to yet another aspect, the invention aims at the use of the composition described above for the manufacture of shoe components, in particular shoe soles.

[0201] Given its good properties, in particular resistance to abrasion, slippage and its low marking on the ground, the composition appears particularly interesting for the manufacture of an outsole or wear sole.

[0202] Due to its good suitability for injection and overmolding, the composition also appears particularly useful for use in the assembly of soles comprising an insole and an outsole or wear sole. D. Articles comprising the composition

[0203] According to yet another aspect, the invention relates to an article made up of, or comprising at least one element made up of, or comprising a composition as described above.

[0204] Said article is preferably selected from the group of footwear components, in particular running, baseball, rugby, soccer, golf and American football shoes, such as soles, in particular outsoles and outsoles, cleats, in particular cleat tips, sports equipment parts such as ski pole parts, racket handles and covers, golf club handles, goalkeeper gloves, treadmills, aquatic equipment such as diving booties, mask and snorkel parts, spectacle frame parts (sleeve, temples, nose pads), ski mask frames, vibration isolation parts in electronics and on machinery, external battery cases, automotive parts and wheel treads.

[0205] Soles, in particular outsoles or external soles, are particularly preferred.

[0206] Articles or elements made of a composition such as described above can be manufactured in particular by injection molding.

[0207] The outsole can have variable dimensions. In general, however, it preferably has a thickness between 0.1 and 30 mm, preferably between 0.5 and 20 mm, advantageously between 1 and 10 mm.

[0208] The sole may be provided with patterns and / or studs.

[0209] The sole may consist of one or more parts. For example, the sole may comprise a central part (midsole) and an outer part (outsole). The The outer part can then be assembled to the central part or be directly attached to the stem.

[0210] The assembly of the parts forming the sole and of the sole to the rest of the shoe can be carried out in particular by sewing, gluing, heat gluing or overmolding.

[0211] Advantageously, the sole formed of an inner sole and an outer sole can be made by injection overmolding of the outer sole, used as an insert, with a PEBA foam, the foam forming the inner sole. E. Recycling

[0212] Advantageously, the composition of the invention is recyclable, after possible separation from other parts, grinding and extrusion. The granules thus obtained can be used again for the manufacture of other articles.

[0213] According to yet another aspect, the invention therefore also relates to a method for recycling an article according to the invention comprising the following successive steps:

[0214] a) recovery, after possible separation, of at least a part of said article in thermoplastic material comprising a composition according to the invention;

[0215] b) grinding the thermoplastic material to obtain particles,

[0216] c) melting of the particles to obtain a molten mixture, and

[0217] d) optionally, adding other components to the molten mixture, and

[0218] e) optionally, the formation of granules, filaments or powders from the molten mixture obtained at the end of step c) or d), and

[0219] f) optionally, shaping of granules, filaments or powders.

[0220] The invention will be explained in more detail in the examples that follow. Examples

[0221] Compositions were prepared using the following polymers:

[0222] PEBA 1: block copolymer of PA 11 (Mn= 600 g / mol) and PTMG (Mn= 1000 g / mol), with 62.5% PTMG, with Shore hardness 90A.

[0223] PEBA 2: block copolymer of PA 12 (Mn= 600 g / mol) and PTMG (Mn= 2000 g / mol), with 76.9% PTMG of Shore 80 A hardness.

[0224] Elastomer 1: Styrene and ethylene / butylene (SE / BS) triblock copolymer containing 32.9% by weight of styrene and 1% by weight of maleic anhydride, sold by Kraton under the name Kraton MD6684 GS-N. Ratio D between the Mn of the rigid blocks and the flexible blocks less than 0.5.

[0225] Elastomer 2: Styrene and ethylene / butylene (SE / BS) triblock copolymer containing between 11.5 and 13.5% by weight of styrene, sold by Kraton under the name Kraton G1645 V. Ratio D between the Mn of the rigid blocks and the flexible blocks less than 0.2.

[0226] Elastomer 3: Styrene and ethylene / butylene (SE / BS) triblock copolymer containing 13% by weight of styrene and 1% by weight of maleic anhydride, sold by Kraton under the name Kraton FG1924. Ratio D between the Mn of the rigid blocks and the flexible blocks less than 0.2.

[0227] Elastomer 4: Styrene and ethylene / butylene (SE / BS) triblock copolymer containing 28.6% styrene, sold by Kraton under the name Kraton MD1542 V. Ratio D between the Mn of the rigid blocks and the flexible blocks less than 0.4.

[0228] Elastomer 5: Styrene and ethylene / butylene (SE / BS) triblock copolymer containing 34% by weight of styrene and between 0.8 and 2% by weight of grafted maleic anhydride, sold by Kraton under the name Kraton MD6186 GO. Ratio D between the Mn of the rigid blocks and the flexible blocks less than 0.6.

[0229] Elastomer 6: Styrene-ethylene / propylene linear block copolymer, sold by LCY under the name Globalprene SEP85O1U. Ratio D between the Mn of the rigid blocks and the flexible blocks less than 0.6.

[0230] Elastomer 7: Thermoplastic polyurethane marketed by Covestro under the name Desmopan 6064A. Ratio D between the Mn of the rigid blocks and the flexible blocks less than 0.8.

[0231] Elastomer 8: saturated styrene / isobutylene / styrene (SIBS) block copolymer sold by Kaneka under the name Sibstar 062T-FD. Ratio D between the Mn of the rigid blocks and the flexible blocks less than 0.8.

[0232] Rubber 1: Rubber powder from used tires (D50 = 160 pm; D90 = 340 pm) marketed by Tyre Recycling Solutions under the name TyreXol® CW 50 which contains between 5 and 17% carbon black.

[0233] Rubber 2: Polybutadiene marketed by Eni Versalis under the name Europrene® NEOCIS BR 60.

[0234] Additive 1: silicone powder consisting of silica compounded with polydimethylsiloxane marketed by Dow under the name Dowsil Trefil F-202.

[0235] Additive 2: Crosslinking agent.

[0236] Additive 3: Statistical copolymer of ethylene, acrylic ester and glycidyl methacrylate marketed by SK Chemicals under the name Lotader® AX8900.

[0237] Different compositions were manufactured by mixing the polymers using a ZSK26 twin-screw extruder. The barrel temperature was set at 190°C. The screw speed was set at 200 rpm with a throughput of 15 kg / h. The quantity of the different ingredients as mass percentages relative to the mass of the final composition is shown in Table 1 below. Example EC2 is manufactured by mixing PEBA and rubber powder in a Buss PR46 co-mixer at a throughput of 15 kg / h and with a co-mixing speed of 250 rpm.

[0238] The compositions, in the form of granules, are then dried under reduced pressure at 70°C in order to achieve a moisture content of less than 0.08% by mass.

[0239] Except for the compositions in the comparative examples, the compositions present They have a homogeneous appearance and a natural color when examined with the naked eye. Comparative examples EC1 and EC2 are black.

[0240] [Table 1]: Composition of examples EC1 EC2 EU EI2 EI3 El 4 El 5 El 6 El 7 El 8 E9 EU 0 PEBA No. 1 - - 70 90 90 - 90 - - 60 94 80 PEBA No. 2 82 60 - - - 90 - 70 60 - - - Elastomer 1 - - 30 - - - - - - - - 10 Elastomer 2 - - - 5 - - - - - - - - Elastomer 3 - - - 5 - - - - - 10 - - Elastomer 4 - - - - 5 - - - - - - - Elastomer 5 - - - - 5 - - - - - - - Elastomer 6 - - - - - 10 10 - - - - - Elastomer 7 - - - - - - - 20 35 - - 10 Elastomer 8 - - - - - - - - - - 5 - Rubber 1 10 40 - - - - - - - - - - Rubber 2 - - - - - - - 9.9 4.9 29.9 - - Additive 1 - - - - - - - - - - 1 - Additive 2 - - - - - - - 0.1 0.1 0.1 - - Additive 3 8 - - - - - - - - - - - Total 100 100 100 100 100 100 100 100 100 100 100 100

[0241] From the compositions manufactured in the form of granules, pellets with a diameter of 16 mm and a thickness of 6 mm, plates of 100x100x2 mm3 and plates of 200x200x0.4mm3 were molded by injection using a Battenfeld BA800 CDC press with unpolished molds and the following injection parameters:

[0242] - Sheath temperature: 170-190°C

[0243] - Nozzle temperature: 190°C

[0244] - Mold temperature: 20°C

[0245] - Cycle time: 60 seconds.

[0246] Specimens of type 1BA shape and of a thickness of 0.4 mm are obtained using a punch from the 200x200x0.4 mm3 plates in order to replicate the maximum elongation supported by a 0.4mm thick base.

[0247] The compositions were evaluated in terms of appearance after abrasion, elongation at break, ground marking and suitability for injection according to the following test protocols. (a) Abrasion resistance

[0248] The abrasion resistance of the compositions is measured according to DIN ISO 4649:2017 (method B with rotating test specimen holder) on 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. (b) Appearance after abrasion

[0249] The appearance of the compositions after abrasion is assessed by visual inspection. The abrasiond pad must be free of filaments, and the pad's contour at the abraded area must be smooth, without any material protrusion exceeding 0.01 mm. The appearance of the pads after testing is rated as satisfactory (+) or unsatisfactory (-). The results are summarized in Table 2 below. (c) Elongation at break in tension

[0250] The 0.4 mm thick 1BA test specimens are conditioned for 14 days at 50% relative humidity and a temperature of 23°C, and their elongation at break is then measured at 200 mm / min, following the rest of the ISO 527 standard. The elongation at break thus measured, required for the application, must be greater than or equal to 150%. The results are summarized in Table 2 below. (d) Ground markings

[0251] The tendency of a composition to leave marks on floors is evaluated according to the SATRA TM223 method. The result is considered satisfactory (+) if the material, after being subjected to the abrasion test according to ISO 4649:2017, method B, does not leave a black mark on a white floor covering, and unsatisfactory (-) if the material creates a black mark on the covering. The results are summarized in Table 2 below. (e) Ability to inject

[0252] The injectability of the composition is assessed by measuring the flow length on an injection molding machine equipped with a mirror-polished spiral mold (spiral flow test) with the following parameters: • Mold temperature: 40°C • Material holding pressure: 900 bars • Temperature profile: 170 / 200 °C • Flow rate: 57 cm³ / s • Cooling time: 20 s

[0253] The test is carried out by injecting the molten composition through the central core, which directly feeds the spiral, 20 mm wide, 1 mm thick, and with a maximum length of 1280 mm. There is a 10 mm gap between the walls of the spiral channels. The average flow length of ten tests performed for each sample is reported in Table 2 below. (f) Slip resistance on wet ground

[0254] The resistance to slipping on wet ground is determined by measuring the coefficient of dynamic friction.

[0255] Samples are prepared by cutting 50 mm x 50 mm x 2 mm plates from the injected plates using a die. The plates are then beveled on two sides on a glazing bench. The plates are then laminated onto rigid PVC sheets and cleaned with a 1:1 volume mixture of demineralized water and ethanol. The dynamic friction coefficient of the samples is then measured on standard STM 603AQ clay tiles wetted with demineralized water, laid flat under a vertical load of 500 N at a speed of 50 mm / min and up to an elongation of 25 mm according to the SATRA TM 144:2011 procedure. A satisfactory composition exhibits a dynamic friction coefficient greater than 0.2. The results are summarized in Table 2 below.

[0256] [Table 2]: Results of the composition evaluation Examples Appearance after abrasion AV after abrasion (mm m3) Dynamic friction coefficient Elongation at break (thickness 0.4mm) [%] Ground marking Flow length [mm] EC1 - 74 0.18 105 - < 1000 EC2 - 180 0.24 52 - <800 EU + 99 0.3 170 + > 1100 EI2 + 78 0.29 169 + > 1100 EI3 + 70 0.31 158 + > 1100 EI4 + 85 0.3 173 + > 1100 EI5 + 92 0.21 165 + > 1100 EI6 + 52 0.23 180 + > 1100 EI7 + 55 0.26 178 + > 1100 EI8 + ND ND 152 + > 1100 EI9 + 63 0.3 190 + >1100 EU0 + ND ND 181 + > 1100

[0257] These experimental results highlight that the compositions according to the invention have a better appearance after abrasion than the comparative examples EC1 and EC2.

[0258] These compositions according to the invention also exhibit excellent injection-molding properties, making it possible to manufacture thinner and therefore lighter soles, thus reducing the weight of the shoes. Furthermore, they exhibit a tensile elongation at break exceeding 150% on a 0.4 mm thick piece, representative of a running shoe, which is very satisfactory.

[0259] Finally, it has been verified that these compositions do not produce ground markings.

[0260] In contrast, the compositions according to the comparative examples exhibit an unsatisfactory appearance after abrasion (see FIG. 1) as well as lower elongation at break. They also leave marks on the ground and, finally, exhibit less suitability for injection. Comparative example 2 is also less resistant to abrasion than the compositions according to the invention, and comparative example 1 has a coefficient of dynamic friction that is too low for the intended application. List of documents cited

[0261] US 2009 / 0292073 A1

[0262] US 2005 / 0004326 Al

[0263] US 8,013,251 B2

[0264] US 2017 / 0242372 Al

Claims

Demands

1. Polymer composition comprising: (a) 55 to 99%, preferably 60 to 95%, advantageously 65 to 90%, and in particular 70 to 85% by weight of polyether block amide (PEBA) having a number-average molar mass ratio of polyamide blocks to polyether blocks less than or equal to 1.0, preferably less than 0.8; (b) 1 to 45%, preferably 5 to 40%, advantageously 10 to 35%, and in particular 15 to 30% by weight of a modifier selected from: i.a thermoplastic elastomer in the form of a block copolymer with a number-average molar mass ratio D of rigid blocks and flexible blocks of less than 0.8, preferably less than 0.7 and advantageously less than 0.5; ii a rubber, raw or crosslinked; (c) 0 to 5%, preferably 0.1 to 4%, including 1 to 2% by weight of additives; and (d) 0 to 5%, preferably 0.5 to 3% by weight of fillers, the sum of the percentages of components (a) to (d) adding up to 100%, and in which the composition comprises less than 4%, preferably less than 2%, advantageously less than 1% by weight of carbon black.

2. Composition according to claim 1, having a Shore hardness of 10A to 100A, preferably from 20A to 90A, and in particular from 40A to 85A.

3. Composition according to claim 1 or 2, wherein the PEBA comprises polyamide blocks selected from the group consisting of PA 6, 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 or their copolymers.

4. Composition according to any one of claims 1 to 3, wherein the PEBA comprises polyether blocks selected from the group consisting of PEG (polyethylene glycol) blocks, PPG blocks (polypropylene glycol), PO3G (polytrimethylene glycol) blocks and PTMG (polytetramethylene glycol) blocks.

5. Composition according to any one of claims 1 to 4, wherein the PEBA comprises PA 11 and PTMG blocks or PA 12 and PTMG blocks.

6. Composition according to any one of claims 1 to 5, wherein where the modifier is a thermoplastic elastomer, it is selected from thermoplastic polyurethanes (TPU) and styrene copolymers.

7. Composition according to any one of claims 1 to 5, wherein where the modifier is a rubber, it is selected from the group consisting of polyisoprene rubber, ethylene-propylene-diene rubber (EPDM), nitrile rubber (NBR), polybutadiene rubber, styrene-butadiene rubber (SBR), butyl rubber (isobutylene-isoprene) and any mixture thereof.

8. Composition according to any one of claims 1 to 5 or 7, wherein where the modifier is a rubber, it is dispersed in the composition in the form of nodules of average diameter in number less than 850 pm, preferably less than 800 pm, advantageously less than 750 pm.

9. A method for manufacturing the composition according to claims 1 to 8, comprising the steps of: (i) mixing in a molten state, preferably in a twin-screw extruder or co-mixer: (a) 55 to 99% by weight of polyether block amide (PEBA) having a number-average molar mass ratio of polyamide blocks to polyether blocks less than or equal to 1.0; (b) 1 to 45% by weight of a modifier selected from: i. a thermoplastic elastomer in the form of a block copolymer with a number-average molar mass ratio D of rigid blocks to flexible blocks less than 0.8; and ii. a rubber, raw or crosslinked; (c) 0 to 5% by weight of additives; and (d) 0 to 5% by weight of fillers; the sum of the percentages by weight of components (a) to (d) adding up to 100%, in which the composition contains less than 4% carbon black, (ii) optionally, shape the mixture into granules, filaments or powder; and (iii) recover the resulting composition.

10. Use of the composition according to any one of claims 1 to 8 for the manufacture of an article selected from the group consisting of shoe components, sports equipment parts, treadmills, aquatic equipment, spectacle frame parts, ski mask frames, vibration isolation parts in electronics and on machinery, external battery cases, automotive parts and wheel treads.

11. Use according to claim 10, wherein the composition is used for the manufacture of an outsole or an outsole.

12. Article comprising the composition according to any one of claims 1 to 8, selected from the group consisting of shoe components, sports equipment parts, treadmills, aquatic equipment, spectacle frame parts, ski mask frames, vibration isolation parts in electronics and on machinery, external battery cases, automotive parts and wheel treads.

13. Article according to claim 12, which is a wear sole or an outsole.

14. A method for recycling an article according to claim 12 or 13, comprising the following successive steps: i. recovering, after possible separation, at least a portion of said article in thermoplastic material comprising a composition according to the invention; ii. grinding the thermoplastic material to obtain particles; iii. melting the particles to obtain a molten mixture; and iv. optionally, adding other components to the molten mixture. 32 V. Optionally, the formation of granules, filaments or powders from the molten mixture obtained at the end of step iii) or iv), and vi. Optionally, shaping of the granules, filaments or powders.

Images