LAMINATE COMPRISING A COMPOSITION BASED ON A POLYAMIDE HOMOPOLYMER OR COPOLYMER AND A THERMOPLASTIC ELASTOMER

Abstract

The invention relates to a laminate comprising at least one central layer disposed between and in contact with a first adjacent layer and a second adjacent layer. The central layer comprises a polymer composition whose polymer matrix comprises 40% to 60% by mass of at least one polymer A comprising repeat units A1 linked together by an amide bond, and 40% to 60% by mass of at least one thermoplastic elastomer B comprising at least one flexible polyether block and at least one rigid polyamide block, the rigid block comprising repeat units B1 linked together by an amide bond, which B1 units are different from the A1 repeat units. The adjacent layers comprise, respectively, polymers C and D having a polyamide block comprising repeat units C1 identical to the A1 repeat units and a polyamide block comprising repeat units D1 identical to the B1 repeat units.

Description

Title of the invention: LAMINATE COMPRISING A HOMOPOLYMER-BASED COMPOSITION OR POLYAMIDE COPOLYMER AND OF A THERMOPLASTIC ELASTOMER

[0001] The field of the present invention is that of laminates comprising an adhesion composition enabling the assembly of at least two layers, in particular layers intended for use in a non-pneumatic bandage.

[0002] A non-pneumatic tire typically comprises a base (mounting band), designed for example for mounting on a rigid rim, a crown reinforcement (or shear band) that connects to a tread, and a deformable structure, such as spokes, ribs, or dimples, this structure being arranged between the base and the crown. Non-pneumatic tires are described, for example, in documents WO 03 / 018332A1 and FR2898077A1.

[0003] In the manufacture of a non-pneumatic tire, for example, the various constituent elements of the tire, in particular the tread, the apex reinforcement, the spokes (or rib or cells) and the mounting strip, are assembled together.

[0004] The assembly of the constituent elements of a non-pneumatic bandage can be carried out by overinjection, by gluing, by riveting or by welding.

[0005] Although riveting allows for the mechanical assembly of the constituent elements, it has the disadvantage of being difficult to implement industrially, and also of increasing the weight of the non-pneumatic tire, which is detrimental to the fuel consumption of vehicles equipped with such tires. Furthermore, riveting has the disadvantage of concentrating mechanical stresses at the rivets, which can potentially initiate crack formation at these points.

[0006] The same applies to welding, which has the disadvantage of being difficult to implement industrially.

[0007] Thus, assemblies made by overinjection or by gluing remain preferred.

[0008] Furthermore, each of the constituent elements of the non-pneumatic tire performs a specific function. The tread, for example, which is designed to come into contact with the ground when the tire is rolling, must have very specific properties, including good grip on both dry and wet surfaces, low rolling resistance, and good wear resistance. The shear strip, for its part, must be deformable and allow for the homogenization of the tire's pressure on the ground. The spokes, meanwhile, serve to support The vehicle's load. As for the mounting band, it must ensure a secure attachment of the wheel to the hub and allow for the transfer of driving forces to the object or braking forces to the vehicle. Therefore, each of these components comprises very specific materials, generally different from one another, and meeting the aforementioned requirements.

[0009] These differences in composition can lead to a decrease in the adhesion properties between the different constituent elements of the bandage.

[0010] Therefore, it remains important to have a laminate comprising a composition exhibiting good adhesion properties with respect to the adjacent layers to be assembled, in particular when the compositions of the adjacent layers are of a different nature.

[0011] Thus, a first object of the invention is a laminate comprising at least: - a central layer of polymeric composition whose polymer matrix comprises: o 40% to 60% by mass of at least one polymer A, which polymer A is a homopolymer or copolymer comprising a polyamide block which includes repeating Al units linked together by an amide bond, o 40% to 60% by mass of at least one thermoplastic elastomer B comprising at least one flexible polyether block and at least one rigid polyamide block, the rigid block comprising repeat units B1 linked together by an amide bond, which B1 units are different from the repeat units Al, - a first adjacent layer of polymeric composition whose polymer matrix comprises more than 50% by mass of at least one polymer C, which polymer C is a homopolymer or copolymer comprising a polyamide block which comprises repeat units Cl linked together by an amide bond, which Cl units are identical to the repeat units Al, - a second adjacent layer of polymeric composition whose polymer matrix comprises more than 50% by mass of at least one polymer D, which polymer D is a homopolymer or copolymer comprising a polyamide block which includes DI repeat units linked together by an amide bond, which DI units are identical to the Bl repeat units, the central layer being disposed between and in contact with the first adjacent layer and the second adjacent layer.

[0012] The present invention also relates to an article, in particular a non-pneumatic bandage, comprising a laminate according to the invention. I- DEFINITIONS

[0013] The expression "composition based on" means a composition comprising the mixture and / or the in situ reaction product of the various constituents used, some of these constituents being able to react and / or intended to react between them, at least partially, during the different phases of manufacturing the composition; the composition can thus be in a totally or partially crosslinked state or in a non-crosslinked state.

[0014] Unless otherwise indicated, the rates of units resulting from the insertion of a monomer into a copolymer are expressed as a molar percentage relative to the total monomer units of the copolymer.

[0015] In the present, unless expressly stated otherwise, all percentages (%) indicated are percentages (%) by mass.

[0016] The term "polymer matrix" refers to all the thermoplastic polymers and thermoplastic elastomers present in a given composition. Various additives, such as plasticizers (liquids or resins) and fillers, potentially present in a given composition, are not included and do not form part of the polymer matrix of that composition.

[0017] On the other hand, any interval of values ​​designated by the expression "between a and b" represents the domain of values ​​from greater than a to less than b (i.e., excluding the bounds a and b), while any interval of values ​​designated by the expression "from a to b" means the domain of values ​​from a to b (i.e., including the strict bounds a and b). In the present case, when an interval of values ​​is designated by the expression "from a to b", the interval represented by the expression "between a and b" is also and preferably designated.

[0018] The compounds mentioned in the description may be of fossil origin or bio-based. In the latter case, they may be partially or totally derived from biomass or obtained from renewable raw materials derived from biomass. Similarly, the compounds mentioned may also come from the recycling of materials already used, that is to say, they may be partially or totally derived from a recycling process, or obtained from raw materials themselves derived from a recycling process. This includes, in particular, polymers, plasticizers, fillers, etc.

[0019] Unless otherwise indicated, all glass transition temperature “Tg” or melting temperature “Tf” values ​​described herein are measured in a known manner by DSC (Differential Scanning Calorimetry) according to ASTM D3418 (1999). II- DESCRIPTION OF THE INVENTION

[0020] As previously stated, the present invention relates to a laminate comprising at least: - a central layer of polymeric composition whose polymer matrix comprises: o 40% to 60% by mass of at least one polymer A, which polymer A is a homopolymer or copolymer comprising a polyamide block comprising repeating Al units linked together by an amide bond, o 40% to 60% by mass of at least one thermoplastic elastomer B comprising at least one flexible polyether block and at least one rigid polyamide block, the rigid block comprising repeat units B1 linked together by an amide bond, which B1 units are different from the repeat units Al, - a first adjacent layer of polymeric composition whose polymer matrix comprises more than 50% by mass of at least one polymer C, which polymer C is a homopolymer or copolymer comprising a polyamide block which comprises repeat units Cl linked together by an amide bond, which Cl units are identical to the repeat units Al, - a second adjacent layer of polymeric composition whose polymer matrix comprises more than 50% by mass of at least one polymer D, which polymer D is a homopolymer or copolymer comprising a polyamide block which includes DI repeat units linked together by an amide bond, which DI units are identical to the Bl repeat units, the central layer being disposed between and in contact with the first adjacent layer and the second adjacent layer.

[0021] By monomer unit (or repeating unit or repeating unit) of a polymer, we mean, in a manner known to those skilled in the art, the smallest constituent unit whose repetition describes said polymer. For example, the monomer unit of PA6 is -[(CH2)5-CONH]- and that of PA 11 is -[(CH2)10-CO-NH]-.

[0022] A person skilled in the art understands the expression "repeating units linked together by an amide bond" with the help of this general knowledge (Odian (2004), "Principles of Polymerization", 4th edition, page 3, Table 1-1).

[0023] In the present, "at least one polymer A" refers to "at least one polymer A, which polymer A is a homopolymer or copolymer comprising a polyamide block which includes repeating Al units linked together by an amide bond".

[0024] The at least one polymer A can thus be a homopolymer consisting of a polyamide block which includes repeat units Al linked together by an amide bond or a homopolymer mixture consisting of a polyamide block which includes repeat units Al linked together by an amide bond, for example of different molecular masses.

[0025] The at least one polymer A may also be a copolymer comprising a polyamide block which includes repeat units Al linked together by an amide bond, i.e. a polymer comprising repeat units Al linked between They are linked by an amide bond and repeating units other than Al without any particular limitation. It is possible that the repeating units other than Al of copolymer A may be identical to or different from the repeating units B1 of at least one thermoplastic elastomer B. Preferably, the repeating units other than Al of copolymer A are different from the repeating units B1 of at least one thermoplastic elastomer B.

[0026] The at least one polymer A may also be a mixture of at least one homopolymer comprising a polyamide block which includes repeat units Al linked together by an amide bond and at least one copolymer comprising a polyamide block which includes repeat units Al linked together by an amide bond.

[0027] When polymer A is a copolymer comprising a polyamide block which includes repeating Al units linked together by an amide bond, the Al units advantageously represent from 20% to 80% by mass of the copolymer, preferably from 30% to 70% by mass of the copolymer.

[0028] When polymer A is a copolymer comprising a polyamide block which includes repeating Al units linked together by an amide bond, it may be, for example, a copolymer comprising at least one block of PA6 and at least one block of a polymer other than PA6, for example, and without limitation, a PA66, PA10 or PA12 block.

[0029] Particularly advantageously, at least one polymer A is a homopolymer or a mixture of homopolymers consisting of a polyamide block which includes repeating units Al linked together by an amide bond.

[0030] Advantageously, the number-average molecular mass (Mn) of the at least polymer A is in the range of 5,000 to 200,000 g / mol, preferably 7,000 to 100,000 g / mol, preferably 10,000 to 30,000 g / mol.

[0031] The number-average molecular weight (Mn) of thermoplastic polymers is determined in a known manner by size-exclusion chromatography (SEC). For example, in the case of polyamides, the sample is first solubilized in hexafluoro-2-propanol with the addition of 0.02 M sodium trifluoroacetate at a concentration of approximately 2 g / L. The apparatus used is a WATERS alliance chromatographic system. The elution solvent is hexafluoro-2-propanol with the addition of 0.02 M sodium trifluoroacetate, the flow rate is 0.5 mL / min, and the system temperature is 35°C. A set of three PHENOMENEX columns in series, with the trade names "Phenogel" ("10 pm 10⁵", "10 pm 10⁴", and "10 pm 10³"), is used. The injected volume of the polymer sample solution is 100 µL. The detector is a WATERS 2410 differential refractometer and its software The associated chromatographic data processing system is the "WATERS MILLENIUM". The calculated average molar masses are relative to a calibration curve established using PMMA standards. The conditions are adaptable by a person skilled in the art.

[0032] The repeating units Al of the polyamide block of polymer A can be of any type provided they are different from the repeating units B1 of the rigid block of the thermoplastic elastomer B. Thus, the polyamide block of polymer A can be a block selected from the group comprising, preferably consisting of, PA6, PA12, PAU, PA4.6, PA6.6, PA6.9, PA6.10, PA6.12, PA10.10, PA10.12, PA6.6 / 6, PA6 / 6.6 / 6 and PA6 / 6.6 / 10. Preferably, the polyamide block of polymer A is a block selected from the group consisting of PA6, PA12, PAU, PA4.6, PA6.6, PA6.9, PA6.10, PA6.12, PA10.10, PA10.12. Preferably, the polyamide block of polymer A is a block chosen from the group consisting of PA6, PA12 and PAU.

[0033] Advantageously, polymer A is a thermoplastic polymer. In other words, it is not a thermoplastic elastomer.

[0034] Examples of commercially available homopolymer polymer A include "Akulon F223-D" from Envalior NV or PA6 in "UDea™ Akulon® K20HG60" from DSM, which is composed of PA6 and reinforced with 60% by mass of glass fiber.

[0035] Examples of commercially available copolymer polymer A include “Ultramid® C3” from BASF, which is a copolymer of PA6 and PA66; “Grilon® TS V0” from EMS-GRIVORY, which is a PA6 / PA66 copolymer with flame retardant; “Vestamid® L1930” from Evonik, which is a copolymer of PA6 and PA12; and “Rilsan® PA6-10” from Arkema, which is a copolymer of PA6 and PA10.

[0036] In the present, "at least one thermoplastic elastomer B" refers to "at least one thermoplastic elastomer B comprising at least one flexible polyether-type block and at least one rigid polyamide-type block the rigid block comprising repeat units B1 linked together by an amide bond, which B1 units are different from the repeat units Al".

[0037] In general, thermoplastic elastomers (abbreviated as "TPE") have an intermediate structure between thermoplastic polymers and elastomers. They are block copolymers, consisting of rigid, thermoplastic blocks linked by flexible, elastomer blocks.

[0038] In what follows, reference is made to a polyether-type block, preferably to an elastomeric block composed of more than 50% by mass (preferably more than 80%, preferably more than 90%, preferably 100%) of a polymer resulting from the polymerization of an ether-type monomer. When reference is made to a block of the polyamide type, it is preferably a block composed of more than 50% by mass (preferably more than 80%, preferably more than 90%, preferably 100%) of a polymer resulting from the polymerization of polyamide monomer.

[0039] Preferably, the melting temperature (Tf) of the thermoplastic elastomer B is in the range of 120°C to 200°C. Advantageously, the Tf of the thermoplastic elastomer is in the range of 140°C to 195°C, preferably from 160°C to 190°C. It may be noted that the Tf of the thermoplastic elastomer corresponds to the Tf of the thermoplastic blocks of the thermoplastic elastomer.

[0040] The number-average molecular weight (Mn) of the thermoplastic elastomer B is preferably between 30,000 and 500,000 g / mol, more preferably between 45,000 and 350,000 g / mol. Even more preferably, the Mn of the thermoplastic elastomer is in the range of 50,000 to 300,000 g / mol, and better still, of 60,000 to 150,000 g / mol.

[0041] The Mn of thermoplastic elastomers is determined in a known manner, by size exclusion chromatography (SEC), in the same way as described above for thermoplastic polymers.

[0042] The thermoplastic elastomer B can be in a linear form. For example, the thermoplastic elastomer is a diblock copolymer: polyether block / polyamide block. The thermoplastic elastomer can also be a triblock copolymer: polyether block / polyamide block / polyether block, that is, a central elastomer block and two terminal thermoplastic blocks, one at each end of the elastomer block. Similarly, the multiblock thermoplastic elastomer can be a linear sequence of polyether blocks and polyamide blocks.

[0043] The thermoplastic elastomer B useful for the purposes of the invention may also be in a star shape with at least three points. For example, the thermoplastic elastomer B may then consist of a star-shaped polyether block with at least three points and a thermoplastic polyamide block located at the end of each of the points of the polyether block. The number of points of the central elastomer may vary, for example, from 3 to 12, and preferably from 3 to 6.

[0044] The thermoplastic elastomer B can also be in a branched or dendrimer form. The thermoplastic elastomer B can then consist of a branched or dendrimer polyether block and a polyamide block, located at the ends of the branches of the dendrimer polyether block.

[0045] Preferably, the thermoplastic elastomer B is in linear and multiblock form.

[0046] The elastomer blocks of the thermoplastic elastomer B for the purposes of the invention, can be any polyether type elastomers known to those skilled in the art.

[0047] These polyether type elastomer blocks preferably have a Tg less than -20°C, preferably having a Tg in a range from -110°C to -35°C, preferably from -90°C to -40°C.

[0048] The polyether-type elastomer blocks of the thermoplastic elastomer B can be composed of monomers selected from cyclic alcohols or ethers, preferably aliphatic cyclic alcohols or ethers, such as, for example, ethanol or tetrahydrofuran. Preferably, at least one flexible polyether-type block of the thermoplastic elastomer B is selected from the group consisting of polytetramethylene glycols (PTMG), polyethylene glycols (PEG), polypropylene ether glycols (PPG), polyhexamethylene ether glycols, polytrimethylene ether glycols (PO3G), poly(3-alkyltetrahydrofurans), and mixtures thereof. Preferably, the polyether elastomer block(s) of the thermoplastic elastomer are chosen from the group consisting of polytetramethylene glycol (PTMG), polyethylene glycol (PEG) and their mixtures.

[0049] Advantageously, the polyether type elastomer blocks of the thermoplastic elastomer have, in total, a Mn ranging from 25,000 g / mol to 350,000 g / mol, preferably from 35,000 g / mol to 250,000 g / mol so as to give the thermoplastic elastomer good elastomeric properties and sufficient mechanical strength compatible with use in the article according to the invention.

[0050] The thermoplastic blocks (rigid polyamide-type blocks) of the thermoplastic elastomer B can be homopolymer or copolymer blocks. In other words, the rigid polyamide-type blocks of the thermoplastic elastomer B can comprise polyamide sequences (or blocks) whose repeating units are all identical or not.

[0051] Preferably, the at least one rigid polyamide-type block of the at least one thermoplastic elastomer B is a homopolymer or copolymer, preferably a homopolymer, comprising from 30% to 80% by mass, preferably from 50% to 70% by mass, of repeat units B1 linked together by an amide bond, which B1 units are different from the AL repeat units

[0052] The repeating units B1 of the rigid block of the thermoplastic elastomer B can be of any type as long as they are different from the repeating units Al of the polyamide block of the polymer A. Thus, the rigid polyamide-type block of the thermoplastic elastomer B can be a block selected from the group comprising, preferably consisting of, PA6, PA12, PAU, PA4.6, PA6.6, PA6.9, PA6.10, PA6.12, PA10.10, PAIO. 12, PA6.6 / 6, PA6 / 6.6 / 6 and PA6 / 6.6 / 10. Preferably, the rigid polyamide block of thermoplastic elastomer B is a block selected from the group consisting of PA6, PA12, PAU, PA4.6, PA6.6, PA6.9, PA6.10, PA6.12, PA10.10, PAIO. 12. Even more preferably, the rigid polyamide block of thermoplastic elastomer B is a block selected from the group consisting of PA6, PA12 and PAU.

[0053] The mass fraction of the flexible polyether type block of the thermoplastic elastomer B can be in the range of 1% to 70%, preferably 10% to 65%, preferably 20% to 60%, and the mass fraction of the rigid polyamide type block of the thermoplastic elastomer B can be in the range of 30% to 99%, preferably 35% to 90%, preferably 40% to 80%.

[0054] Particular thermoplastic elastomers in which the thermoplastic blocks are polyamides are usually denoted TPE-A or TPA (thermoplastic copolyamide) or PEBA (block amide copolyether), and they are particularly preferred for the purposes of the invention. Advantageously, thermoplastic elastomer B is chosen from the group consisting of polyether and polyamide block copolymers (PEBA), said polyamide blocks preferably being a homopolymer or copolymer, preferably a homopolymer, of PAU.

[0055] According to the invention, the thermoplastic blocks of the thermoplastic elastomer B have, in total, an average number molecular mass ("Mn") ranging from 5,000 g / mol to 150,000 g / mol, preferably from 10,000 to 100,000 g / mol, so as to give the thermoplastic elastomer good elastomeric properties and sufficient mechanical strength compatible with use in the article according to the invention.

[0056] As an example of commercially available thermoplastic elastomer B, one can cite for example the "Pebax® Rnew® 55R53 SP 01" from the company Arkema which is a TPE based on PAU.

[0057] In the composition of the central layer of the laminate according to the invention, the content of polymer A is preferably in the range of 41% to 59% by mass, preferably from 45% to 55% by mass, relative to the mass of the polymer matrix. Furthermore, in the composition of the central layer of the laminate according to the invention, the content of thermoplastic elastomer B is in the range of 41% to 59% by mass, preferably from 45% to 55% by mass, relative to the mass of the polymer matrix.

[0058] Advantageously, the polymer matrix does not comprise any polymer other than at least polymer A and at least one thermoplastic elastomer B, or comprises less than 20% by mass, preferably less than 10% by mass, preferably less than 5% by mass. Preferably, the polymer matrix does not comprise any polymer other than at least polymer A and at least one thermoplastic elastomer B, i.e., at least one polymer A and at least one thermoplastic elastomer B constitute 100% by mass of the polymer matrix.

[0059] The composition of the central layer of the laminate according to the invention may comprise compounds other than at least one polymer A and at least one thermoplastic elastomer B. These may be additives, known to those skilled in the art, for use with thermoplastics or thermoplastic elastomers. Examples of additives include plasticizers, fillers, processing aids, pigments, and protective agents such as UV stabilizers, ozone stabilizers, antioxidants, and anti-fatigue agents. Of course, reinforcing elements such as metal or textile cables, inorganic fibers (e.g., glass fibers), etc., which may potentially be embedded in a composition, are not additives and are therefore not part of the composition under consideration.

[0060] The rate of additives in the composition of the central layer can represent from 0% to 20% by mass, for example from 1% to 10% by mass, relative to the mass of the composition according to the invention.

[0061] Thus, the total proportion of polymer A and thermoplastic elastomer B in the composition can be from 80% to 100% by mass, for example from 90% to 99% by mass.

[0062] The laminate according to the invention comprises a first adjacent layer of polymeric composition, the polymer matrix of which comprises more than 50% by mass of at least one polymer C, which polymer C is a homopolymer or copolymer comprising a polyamide block comprising repeat units Cl linked together by an amide bond, which Cl units are identical to the AL repeat units

[0063] In the present, "at least one polymer C" refers to "at least one polymer C, which polymer C is a homopolymer or copolymer comprising a polyamide block which includes repeat units Cl linked together by an amide bond, which Cl units are identical to the repeat units Al".

[0064] The at least one polymer C can thus be a homopolymer consisting of a polyamide block which includes repeat units Cl linked together by an amide bond or a homopolymer mixture consisting of a polyamide block which includes repeat units Cl linked together by an amide bond, for example of different molecular masses.

[0065] The at least one polymer C may also be a copolymer comprising a polyamide block which includes repeat units Cl linked together by an amide bond, i.e. a polymer comprising repeat units Cl linked together by an amide bond and repeat units other than Cl without limitation particular. It is possible that the repeat units other than Cl of the copolymer C are identical or different from the repeat units B1 of at least one thermoplastic elastomer B. Preferably, the repeat units other than Cl of the copolymer C are different from the repeat units B1 of at least one thermoplastic elastomer B.

[0066] The at least one polymer C may also be a mixture of at least one homopolymer comprising a polyamide block which includes repeat units Cl linked together by an amide bond and at least one copolymer comprising a polyamide block which includes repeat units Cl linked together by an amide bond.

[0067] When polymer C is a copolymer comprising a polyamide block which includes repeat units Cl linked together by an amide bond, the Cl units advantageously represent from 5% to 95% by mass of the copolymer, for example from 9% to 70% by mass of the copolymer.

[0068] The repeating units Cl of the polyamide block of polymer C can be of any type provided they are identical to the repeating units Al of polymer A. Thus, the polyamide block of polymer C can be a block selected from the group comprising, preferably, PA6, PA12, PAU, PA4.6, PA6.6, PA6.9, PA6.10, PA6.12, PA10.10, PA10.12, PA6.6 / 6, PA6 / 6.6 / 6 and PA6 / 6.6 / 10. Preferably, the polyamide block of polymer C is a block selected from the group comprising PA6, PA12, PAU, PA4.6, PA6.6, PA6.9, PA6.10, PA6.12, PA10.10, PA10.12. Even more preferably, the polyamide block of polymer C is a block selected from the group comprising PA6, PA12 and PAU.

[0069] Advantageously, polymer C is a thermoplastic polymer. In other words, it is not a thermoplastic elastomer.

[0070] Advantageously, the Mn of at least one polymer C is in the range of 5,000 to 200,000 g / mol, preferably 7,000 to 100,000 g / mol, preferably 10,000 to 30,000 g / mol.

[0071] Advantageously, the polymer matrix of the first adjacent layer comprises more than 60% by mass, preferably more than 65% by mass, preferably more than 80% by mass of polymer C. Preferably, the polymer matrix of the composition of the first adjacent layer may not comprise any polymer other than at least one polymer C, or may comprise less than 20% by mass, preferably less than 10% by mass, preferably less than 5% by mass. Even more preferably, the polymer matrix may not comprise any polymer other than at least one polymer C, that is to say, at least one polymer C constitutes 100% by mass of the polymer matrix of the composition of the first adjacent layer of the laminate according to the invention.

[0072] The composition of the first layer may include compounds other than at least one polymer C. These may include, in particular, the aforementioned additives for the composition according to the invention.

[0073] The rate of additives in the composition of the first layer can represent from 0% to 20% by mass, for example from 1% to 10% by mass, relative to the mass of the composition according to the invention.

[0074] Thus, preferably, the total rate of polymer C in the composition of the first adjacent layer can be from 80% to 100% by mass, for example from 90% to 99% by mass.

[0075] The laminate according to the invention comprises a second adjacent layer of polymeric composition, the polymer matrix of which comprises more than 50% by mass (preferably more than 80%, preferably more than 90%, preferably 100%) of at least one polymer D, which polymer D is a homopolymer or copolymer comprising a polyamide block which comprises DI repeat units linked together by an amide bond, which DI units are identical to the Bl repeat units.

[0076] In the present, "at least one polymer D" refers to "at least one polymer D, which polymer D is a homopolymer or copolymer comprising a polyamide block which includes DI repeat units linked together by an amide bond, which DI units are identical to the Bl repeat units".

[0077] The at least one polymer D can thus be a homopolymer consisting of a polyamide block which includes DI repeat units linked together by an amide bond or a homopolymer mixture consisting of a polyamide block which includes DI repeat units linked together by an amide bond, for example of different molecular masses.

[0078] The at least one polymer D may also be a copolymer comprising a polyamide block that includes DI repeat units linked together by an amide bond, i.e., a polymer comprising DI repeat units linked together by an amide bond and non-DI repeat units without any particular limitation. It is possible that the non-DI repeat units of copolymer D may be identical to or different from the Al repeat units of the at least one polymer A. Preferably, the non-DI repeat units of copolymer D are different from the Bl repeat units of the at least one polymer A.

[0079] The at least one polymer D may also be a mixture of at least one homopolymer comprising a polyamide block which includes DI repeat units linked together by an amide bond and at least one copolymer comprising a polyamide block which includes DI repeat units linked together by an amide bond.

[0080] When the polymer D is a copolymer comprising a polyamide block which includes DI repeat units linked together by an amide bond, the DI units advantageously represent from 5% to 95% by mass of the copolymer, for example from 9% to 70% by mass of the copolymer.

[0081] The repeat units DI of the polyamide block of polymer D can be of any type provided they are identical to the repeat units B1 of the rigid block of thermoplastic elastomer B. Thus, the polyamide block of polymer D can be a block selected from the group comprising, preferably consisting of, PA6, PA12, PAU, PA4.6, PA6.6, PA6.9, PA6.10, PA6.12, PA10.10, PA10.12, PA6.6 / 6, PA6 / 6.6 / 6 and PA6 / 6.6 / 10. Preferably, the polyamide block of polymer D is a block selected from the group consisting of PA6, PA12, PAU, PA4.6, PA6.6, PA6.9, PA6.10, PA6.12, PA10.10, PA10.12. Preferably, the polyamide block of polymer D is a block chosen from the group consisting of PA6, PA12 and PAU.

[0082] Advantageously, polymer D is a thermoplastic polymer. In other words, it is not a thermoplastic elastomer.

[0083] Advantageously, the Mn of the at least polymer D is in a range of 5,000 to 200,000 g / mol, preferably 7,000 to 100,000 g / mol, preferably 10,000 to 30,000 g / mol.

[0084] Advantageously, the polymer matrix of the second adjacent layer comprises more than 60% by mass, preferably more than 65% by mass, preferably more than 80% by mass of polymer D. Preferably, the polymer matrix of the composition of the second adjacent layer does not comprise any polymer other than at least one polymer D, or comprises less than 20% by mass, preferably less than 10% by mass, preferably less than 5% by mass. Even more preferably, the polymer matrix comprises no polymer other than at least one polymer D, that is to say, at least one polymer D constitutes 100% by mass of the polymer matrix of the composition of the second adjacent layer of the laminate according to the invention.

[0085] The composition of the second adjacent layer may include compounds other than at least one polymer D. These may include, in particular, the aforementioned additives for the composition according to the invention.

[0086] The rate of additives in the composition of the second adjacent layer can represent from 0% to 20% by mass, for example from 1% to 10% by mass, relative to the mass of the composition according to the invention.

[0087] Thus, preferably, the total percentage of polymer D in the composition of the second adjacent layer can be from 80% to 100% by mass, for example from 90% to 99% by mass. mass.

[0088] As examples of commercially available homopolymer C or D polymers, one can cite, for example, "Rilsan® - Polyamide 11" from the company Arkema.

[0089] Examples of commercially available C or D copolymer polymers include "Rilsan® Clear G850" from Arkema.

[0090] Advantageously, polymer C is different from polymer D. This is particularly interesting when it comes to adhering layers of different nature together thanks to the composition of the central layer of the laminate according to the invention.

[0091] Preferably, polymer A comprises at least one PA6 polyamide block, thermoplastic elastomer B comprises the rigid polyamide block of at least one thermoplastic elastomer B comprises a PAU polyamide block, polymer C comprises at least one PA6 block and polymer D comprises at least one PAU polyamide block.

[0092] The compositions of the central and adjacent layers of the laminate according to the invention can be manufactured in a manner known to those skilled in the art, for example by mixing the various constituents in a molten state in a suitable mixer or extruder (twin-screw extruders, single-screw extruders, mixers). The compositions can be granulated for subsequent use (simply by remelting) or directly injected into a mold or an extrusion or co-extrusion device.

[0093] The laminate according to the invention can be manufactured (in other words, the layers of the laminate can be assembled) in a manner known to a person skilled in the art, for example by overinjection using an injection press or by assembly by welding.

[0094] The laminate according to the invention can be used in various articles, in particular when the article requires improved adhesion between two compositions of different nature that constitute it.

[0095] Thus, the present invention also relates to an article comprising at least one laminate according to the invention.

[0096] The article can find applications in a wide variety of fields, for example in food packaging, electronics, automotive, and medical materials. A specific application in the field of non-pneumatic vehicle tires is described below.

[0097] Thus, the article according to the invention can be a non-pneumatic bandage.

[0098] Preferably, the article is a non-pneumatic tire comprising a tread, an annular band, a plurality of spokes extending transversely and radially within the annular band, a mounting band for connecting the plurality of spokes to a wheel, the tire comprising cushions made of a composition of the central layer of the laminate according to the invention, said cushions being arranged between and in contact with the spokes and the radially inner portion of the annular strip and / or between and in contact with the spokes and the radially inner portion of the mounting strip. Preferably, the radially inner portion of the annular strip and / or the radially inner portion of the mounting strip is made of a composition of the first adjacent layer of the laminate according to the invention, and the spokes in contact with the cushions are made of a composition of the second adjacent layer of the laminate according to the invention. III- EXAMPLES

[0099] Adhesion tests were carried out to determine the quality of the interface between two materials in contact with each other. For this purpose, the following protocol was implemented, which is based on the ASTM D1002 (2019) standard.

[0100] Various sheets of "Material A" were prepared. Materials MAI and MA3 were prepared by injection molding using a Béwéplast Boy XS injection molding machine in an 80x20x2mm mold. The injection conditions were as follows: material temperature: 280°C, mold temperature during injection: 80°C, injection pressure: 1000 bar. Material MA2 is a strip that was cut to the desired dimensions (80x20x2mm). The Material A samples tested were as follows: MAY: “Akulon® F223-D” from the company Envalior NV which is a PA6; MA2: “UDea™ Akulon® K20HG60” from the company DSM which is composed of PA6 in which approximately 60% by mass of fiberglass is embedded at least partially; MA3: “Rilsan® Clear G850” from the company Arkema which is a copolymer comprising a PAU block.

[0101] In these examples, the materials MAI and MA2 conform to the first adjacent layer of the laminate according to the invention and the material MA3 conforms to the second adjacent layer of the laminate according to the invention.

[0102] Various mixtures of "Material B" were prepared by mixing a thermoplastic (TP), a thermoplastic elastomer (TPE), or a mixture thereof, using a Krauss Maffei "32D Twin Screw Extruder". The mixing conditions were as follows: rotation speed: 300 rpm, total throughput: 3 kg / h, temperature at the extruder barrel: 220°C. The mixture was immediately granulated under water at the screw outlet on a GALA MAP (Manual Adjustable Pelletizer). The Material B tested were as follows: MB1: 100% by mass of MAI; MB2: mixture of 50% by mass of MAI and 50% by mass of "Arkema Pebax® Rnew® 55R53 SP 01" from the company Arkema which is a TPE whose rigid blocks are in PAU; MB3: mixture of 30% by mass of MAI and 70% by mass of "Arkema Pebax® Rnew® 55R53 SP 01"; MB4: 100% by mass of MA3.

[0103] Materials MB1, MB3, and MB4 are control compositions that do not conform to the composition of the core layer of the laminate according to the invention. Material MB2, on the other hand, does conform to the composition of the core layer of the laminate according to the invention.

[0104] Test specimens of "Material A+B" were produced by over-injecting "Material B" into a 20x20 mm area at one end of a "Material A" wafer, which had been previously cleaned with ethanol before being placed in its dedicated cavity in the over-injection mold. The over-injection conditions were as follows: material temperature: 280°C, mold temperature during injection: 80°C, injection pressure: 1000 bar. This resulted in test specimens consisting of two plates, one of "Material A" and the other of "Material B," both measuring 80x20x2 mm, with a 20x20 mm overlap area at the ends of the wafers.

[0105] Once cooled, the test specimens were placed in a tensile testing machine (Instron 6800 series) by inserting the free ends of the plates into the jaws. The longitudinal force required to break the specimens was measured using the "BlueHill" software associated with Instron tensile testing machines.

[0106] The adhesion results, expressed in Newtons (N), of different specimens of "Material A" / "Material B" are presented in Table 1 below.

[0107] The higher the adhesion value, the better the adhesion. Since Materials B are intended to bond two compositions of Material A of different natures, it is understood that the best Material B will be the one that exhibits the highest minimum adhesion result with respect to two Materials A.

[0108] [Tables] MB1 (PA6) (control) MB2 (50% PA6 + 5 0% TPE with PAU blocks) (invention) MB3 (30% PA6 + 7 0% TPE with PAU blocks) (control) MB4 (TPE with PAU blocks) (control) MAI (PA6) 2231 1383 792 582 MA2 (PA6 + fibers of glass) 923 1115 648 150 MA3 (P Ail block copolymer) 336 1357 1512 844

[0109] The results presented in Table 1 above show that only the MB2 material conforming to the central layer of the laminate according to the invention exhibits results greater than 1000 N with respect to the MAI, MA2 and MA3 materials.

[0110] As expected, the MAI material exhibits stronger adhesion to itself than to other materials (MB2, MB3, MB4). Conversely, and surprisingly, Material MB2 (consisting of a 50% by mass mixture of MAI and 50% by mass of TPE with rigid blocks made of PAU) adheres better to Material MA3 (consisting of a copolymer comprising a PA11 block) than Material MB3 (consisting of TPE with rigid blocks made of PA11) adheres better to Material MA3.

[0111] Similarly, it would have been expected that the MA2 material (made of PA6) would adhere better to MB1 (made of PA6) than to MB2 (made of a mixture of 50% by mass PA6 and 50% by mass TPE, the rigid blocks of which are made of PA11). As previously stated, the MA2 material is a compound comprising 60% by mass of reinforcing elements (glass fibers) embedded at least partially in a PA6 composition. This implies that some of the glass fibers are exposed on the surface of the MA2 material plate. The MB2 material, according to the invention, unexpectedly exhibits better adhesion to the MA2 material (and therefore to the glass fibers) than the MBL material.

[0112] The various tests carried out by the Applicant have shown that this surprising effect is obtained when Material B comprises between 40% and 60% by mass of at least one polymer A and between 40% and 60% by mass of at least one thermoplastic elastomer B. Beyond these rates, the surprising effect described above is not observed, as shown by the adhesion tests of material MB3 on materials MAI and MA2.

[0113] The present invention therefore provides very interesting materials for improving the adhesion of two materials of different natures. It finds applications in many fields, for example in that of non-pneumatic bandages.

Claims

1. Demands Laminate containing at least: - a central layer of polymeric composition whose polymer matrix comprises: • 40% to 60% by mass of at least one polymer A, which polymer A is a homopolymer or copolymer comprising a polyamide block comprising repeating Al units linked together by an amide bond, • 40% to 60% by mass of at least one thermoplastic elastomer B comprising at least one flexible polyether block and at least one rigid polyamide block, the rigid block comprising repeat units B1 linked together by an amide bond, which B1 units are different from the repeat units Al, - a first adjacent layer of polymeric composition whose polymer matrix comprises more than 50% by mass of at least one polymer C, which polymer C is a homopolymer or copolymer comprising a polyamide block which includes repeat units Cl linked together by an amide bond, which Cl units are identical to the repeat units Al, - a second adjacent layer of polymeric composition whose polymer matrix comprises more than 50% by mass of at least one polymer D, which polymer D is a homopolymer or copolymer comprising a polyamide block comprising DI repeat units linked together by an amide bond, which DI units are identical to the Bl repeat units, the central layer being arranged between and in contact with the first adjacent layer and the second adjacent layer.

2. Laminated according to claim 1, wherein the polymer A content is in the range of 41% to 59% by mass, preferably 45% to 55% by mass, relative to the mass of the polymer matrix of the middle layer.

3. Laminated according to any one of the preceding claims, wherein the thermoplastic elastomer B content is in the range of 41% to 59% by mass, preferably 45% to 55% by mass, relative to the mass of the polymer matrix of the middle layer.

4. Laminated according to any one of the preceding claims, wherein at least one flexible polyether-type block of thermoplastic elastomer B is selected from the group consisting of polytetramethylene glycol (PTMG), polyethylene glycols (PEG), polypropylene ether glycol (PPG), polyhexamethylene ether glycol, polytrimethylene ether glycol (PO3G), poly(3-alkyltetrahydrofurans), and mixtures thereof, preferably from the group consisting of polytetramethylene glycol (PTMG), polyethylene glycols (PEG) and mixtures thereof.

5. Laminated according to any one of the preceding claims, wherein at least one rigid polyamide-type block of at least one thermoplastic elastomer B comprises from 30% to 80% by mass, preferably from 50% to 70% by mass of Bl repeat units.

6. Laminated according to any one of the preceding claims, wherein the mass fraction of flexible polyether-type block of at least one thermoplastic elastomer B is in the range of 1% to 70%, preferably 10% to 65%, preferably 20% to 60%, and the mass fraction of rigid polyamide-type block of at least one thermoplastic elastomer B is in the range of 30% to 99%, preferably 35% to 90%, preferably 40% to 80%.

7. Laminated according to any one of the preceding claims, wherein the polymer matrix of the middle layer does not comprise any polymer other than at least one polymer A and at least one thermoplastic elastomer B, or comprises less than 20% by mass, preferably less than 10% by mass, preferably less than 5% by mass.

8. Laminated according to any one of the preceding claims, wherein the polymer matrix of the first adjacent layer comprises more than 60% by mass, preferably more than 65% by mass, preferably more than 80% by mass of polymer C.

9. Laminated according to any one of the preceding claims, wherein the polymer matrix of the second adjacent layer comprises more than 60% by mass, preferably more than 65% by mass, preferably more than 80% by mass of polymer D.

10. Laminated according to any one of the preceding claims, wherein polymer A, polymer C and polymer D are thermoplastic polymers.

11. Article comprising a laminate according to any one of claims 1 to 10.

12. Article according to claim 11, the article being a non-pneumatic tire comprising a tread, an annular band, a plurality of spokes extending transversely and radially within the annular band, a mounting band for connecting the plurality of spokes with a wheel, characterized in that the tire comprises cushions made of a composition of the central layer as defined in any one of claims 1 to 10, said cushions being arranged between and in contact with the spokes and the radially inner part of the annular band and / or between and in contact with the spokes and the radially inner part of the mounting band.