PEBA for direct adhesion to TPU containing hollow glass beads

Abstract

The present invention relates to a molded article comprising a first polymeric material comprising at least one copolymer comprising a PA polyamide block and a PE polyether block (PEBA) and a second polymeric material comprising at least one thermoplastic polyurethane (TPU), the first polymeric material directly adhering to a second adhesive polymeric material, the second polymeric material comprising hollow glass beads. The present invention also relates to the assembly of the first polymeric material onto the second polymeric material comprising hollow glass beads by a direct adhesion method.

Description

[Technical field]

[0001] The present invention relates to a molded article comprising a first polymeric material comprising at least one copolymer comprising a PA polyamide block and a PE polyether block (PEBA) and a second polymeric material comprising at least one thermoplastic polyurethane (TPU), the first polymeric material being directly bonded to the second polymeric material, the second polymeric material comprising hollow glass beads. The present invention also relates to the assembly of the first polymeric material onto the second polymeric material comprising hollow glass beads by a direct bonding method. [Background technology]

[0002] Materials based on thermoplastic elastomer (TPE) polymers, such as PEBA or TPU copolymers or copolyether block esters (CoPEs), are known for their use in the manufacture of automotive parts, sporting goods, especially sports shoes, electrical and electronic equipment parts, medical device parts, etc.

[0003] Such applications may require the combination of materials with similar or different chemical and mechanical properties. Assembly may be performed by methods such as molding or extrusion, optionally cutting parts and then gluing and pressing these parts together, or direct bonding of these TPEs.

[0004] The term "direct bonding method" is understood to mean a bonding method that does not add a binder, in particular a bonding method that does not add a glue or adhesive. Glue or adhesive can cause pollution, which makes recycling more difficult. Compared with traditional bonding methods that generally use organic solvent-based adhesives and involve many complicated methods, direct bonding methods are more economical and non-polluting. Examples of direct bonding methods can include overmolding, hot pressing, coextrusion, thermoforming, co-injection, and any other possible bonding methods that use one or more of the traditional methods such as injection molding, extrusion molding, and / or blow molding.

[0005] More specifically, the overmolding technique consists of injecting a material into an insert placed at the bottom of a mold. The adhesion between the two materials is achieved by their adhesiveness in the molten state and by the compatibility of the overmolding material with the insert.

[0006] Unfortunately, the adhesion levels of the TPE-based materials in systems obtained by direct bonding are not always optimal.

[0007] Furthermore, these TPE-based materials may contain additives and reinforcements such as fibers or glass beads to improve mechanical properties for electronic, sports, automotive or industrial applications. Furthermore, the addition of hollow glass beads has been considered in the past, which allows the end product to be lighter, thus reducing energy consumption or consuming as little energy as possible during use.

[0008] However, these additives and / or reinforcements can have detrimental effects, such as adhesion problems during assembly. For example, in "Investigation of the interfacial adhesion of glass bead-filled multicomponent injection molded composites, Suplicz et al., IOP Conf. Series: Materials Science and Engineering 903 (2020)," adhesion failure was observed to result in reduced bond strength between two overmolded materials containing glass fibers or glass beads.

[0009] Therefore, there is a real need to provide molded articles that have good adhesion between these various materials, including additives and / or reinforcing materials, especially materials that include hollow glass beads. Summary of the Invention

[0010] The present invention relates first to a molded article comprising a first polymeric material comprising at least one copolymer comprising polyamide blocks and polyether blocks (PEBA) and a second polymeric material comprising at least one thermoplastic polyurethane (TPU), the first polymeric material being directly adhered to the second polymeric material, the second polymeric material comprising hollow glass beads.

[0011] According to one embodiment, the adhesive strength between two polymeric materials, expressed as peel strength in kgf / cm, is greater than or equal to 10 kgf / cm, preferably greater than or equal to 12 kgf / cm.

[0012] According to one embodiment, the hollow glass beads have a content of 3% to 25% by weight relative to the total weight of the second polymeric material.

[0013] According to one embodiment, the hollow glass beads contain zinc oxide having a content of 1.0% by weight or more relative to the total weight of the hollow glass beads, preferably 2.0% by weight or more relative to the total weight of the hollow glass beads.

[0014] The present invention makes it possible to meet the above-mentioned needs and also provides molded articles having a desired low density in addition to good direct adhesion between different TPE materials.

[0015] The invention also provides a method for directly adhering a first polymeric material comprising at least one PEBA to a second polymeric material comprising at least one TPU and hollow glass beads, characterized in that the assembly is carried out by a method comprising heating the first polymeric material, and this material, melted or softened under heating, is brought into contact with at least a portion of the second polymeric material so as to adhere the two materials together.

[0016] It has been surprisingly discovered that the presence of hollow glass beads makes it possible to provide a molded article having reduced density without affecting the adhesion between a first polymeric material and a second polymeric material, more specifically, the adhesion between two polymeric materials is maintained or improved despite the presence of hollow glass beads near the interface of the two materials.

[0017] For the purposes of the present invention, the expressions "maintained adhesion" or "similar adhesion" are understood to mean a ratio between the adhesion of a material in the presence of hollow glass beads and the adhesion of the same material without hollow glass beads of greater than 75%.

[0018] The invention also relates to the use of the above defined molded article for the manufacture of sports goods, shoe materials, personal protective equipment, automotive parts, construction parts, optical equipment parts, electrical and electronic equipment parts (e.g. AR / VR headsets, smartphone parts, computer hardware), medical equipment parts such as catheters, or power transmission or conveyor belts. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The invention will now be described in more detail and in a non-limiting manner.

[0020] molded product Firstly, the invention relates to a moulded article comprising a first polymeric material and a second polymeric material, the first polymeric material being directly adhered to the second polymeric material. The term "adhere directly" or "direct adhesion" is understood to mean adhesion without the addition of a binder, in particular without the addition of a glue or adhesive. Preferably, this moulded article is obtained by the direct adhesion method described below.

[0021] First polymer material The first polymeric material according to the invention comprises at least one copolymer comprising PA polyamide blocks and PE polyether blocks (PEBA).

[0022] PEBA copolymers can be produced by the polycondensation of a polyamide block having a reactive end with a polyether block having a reactive end, e.g.: 1) polycondensation of a polyamide block having a diamine chain end and a polyoxyalkylene block having a dicarboxylic acid chain end; 2) polycondensation of polyamide blocks containing dicarboxylic acid chain ends with polyoxyalkylene blocks containing diamine chain ends (known as polyetheramines) (obtained by cyanoethylation and hydrogenation of α,ω-dihydroxylated aliphatic polyoxyalkylene blocks (known as polyetherdiols); 3) Polycondensation of polyamide blocks having dicarboxylic acid chain ends with polyether diols (the resulting product is in this particular case a polyether ester amide). arises from.

[0023] Polyamide blocks with diamine chain ends result, for example, from the condensation of polyamide precursors in the presence of a chain-limiting diamine. Polyamide blocks with dicarboxylic acid chain ends result, for example, from the condensation of polyamide precursors in the presence of a chain-limiting dicarboxylic acid.

[0024] Three types of polyamide blocks may be advantageously used.

[0025] In the first type, the polyamide blocks result from the condensation of dicarboxylic acids, in particular those having from 4 to 36 carbon atoms, preferably those having from 6 to 18 carbon atoms, with aliphatic or aromatic diamines, in particular those having from 2 to 20 carbon atoms, preferably those having from 4 to 14 carbon atoms.

[0026] Examples of dicarboxylic acids include 1,4-cyclohexanedicarboxylic acid, butanedioic acid, adipic acid, azelaic acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, terephthalic acid, and isophthalic acid, as well as dimerized fatty acids, which preferably have a dimer content of at least 98%; they are preferably hydrogenated; they are, for example, the products sold under the brand name Pripol by Croda, or under the brand name Empol by BASF, or under the brand name Radiacid by Oleon, and polyoxyalkylene α,ω-diacids.

[0027] Examples of diamines include tetramethylenediamine, hexamethylenediamine, 1,10-decamethylenediamine, dodecamethylenediamine, trimethylhexamethylenediamine, bis(4-aminocyclohexyl)methane (BACM), bis(3-methyl-4-aminocyclohexyl)methane (BMACM), and isomers of 2,2-bis(3-methyl-4-aminocyclohexyl)propane (BMACP), and para-aminodicyclohexylmethane (PACM), and isophoronediamine (IPDA), 2,6-bis(aminomethyl)norbornane (BAMN), and piperazine (Pip).

[0028] For example, PA412, PA414, PA418, PA610, PA612, PA614, PA618, PA912, PA1010, PA1012, PA1014 and PA1018 blocks. In the PA XY notation, conventionally, X represents the number of carbon atoms originating from the diamine residue and Y represents the number of carbon atoms originating from the diacid residue.

[0029] In the second type, the polyamide blocks result from the condensation of one or more α,ω-aminocarboxylic acids and / or one or more lactams containing from 6 to 12 carbon atoms in the presence of a dicarboxylic acid containing from 4 to 36 carbon atoms or in the presence of a diamine. Examples of lactams include caprolactam, oenantholactam, lauryllactam. Examples of α,ω-aminocarboxylic acids include aminocaproic acid, 7-aminoheptanoic acid, 11-aminoundecanoic acid and 12-aminododecanoic acid.

[0030] Advantageously, the second type of polyamide block is made of PA 11, PA 12 or PA 6.

[0031] In the third type, the polyamide blocks result from the condensation of at least one α,ω-aminocarboxylic acid (or lactam), at least one diamine, and at least one dicarboxylic acid. In the notation PA X, X represents the number of carbon atoms derived from the amino acid residue.

[0032] In this case, the polyamide PA block is in the presence of a chain limiting agent selected from dicarboxylic acids, - polycondensation of a diamine containing X carbon atoms, - polycondensation of a dicarboxylic acid having Y carbon atoms, - polycondensation of comonomers {Z} ((X1,Y1) are different from (X,Y)) selected from lactams and α,ω-aminocarboxylic acids containing Z carbon atoms and an equimolar mixture of at least one diamine containing X1 carbon atoms and at least one dicarboxylic acid containing Y1 carbon atoms, Prepared from said comonomer {Z} is incorporated in a weight proportion ranging at most 50%, preferably at most 20% and even more advantageously at most 10% relative to the total amount of polyamide precursor monomers.

[0033] Advantageously, a dicarboxylic acid having Y carbon atoms is used as chain limiter, which is introduced in excess with respect to the stoichiometry of the diamine.

[0034] In one variant of this third type, the polyamide blocks result from the condensation, optionally in the presence of a chain limiter, of at least two α,ω-amino carboxylic acids, or of at least two lactams containing from 6 to 12 carbon atoms, or of one lactam and one amino carboxylic acid not having the same number of carbon atoms. The α,ω-amino carboxylic acids, lactams, diamines and dicarboxylic acids may be of the types described above.

[0035] As examples of polyamide blocks of the third type, mention may be made of the following: 66 / 6, 66 / 610 / 11 / 12.

[0036] Preferably, the polymer comprises from 1% to 80% by weight of polyether blocks and from 20% to 99% by weight of polyamide blocks, more preferably from 4% to 80% by weight of polyether blocks and from 20% to 96% by weight of polyamide blocks.

[0037] The polyether blocks are composed of alkylene oxide units. The blocks may be derived in particular from PEG (polyethylene glycol) blocks, i.e. composed of ethylene oxide units, PPG (propylene glycol) blocks, i.e. composed of propylene oxide units, PO3G (polytrimethylene glycol) blocks, i.e. composed of polytrimethylene glycol ether units, and / or PTMG (polytetramethylene glycol) blocks, i.e. composed of tetramethylene glycol units, also known as polytetrahydrofuran. The PEBA copolymers may contain several types of polyethers in their chain, the copolyethers possibly being in block or statistical form.

[0038] It is also possible to use blocks obtained by oxyethylation of bisphenols, such as bisphenol A. The latter products are described in patent document EP 613919.

[0039] The polyether blocks may also be comprised of ethoxylated primary amines. Examples of ethoxylated primary amines include those of the formula: The product of JPEG2025507731000001.jpg35170 can be mentioned. where m and n are between 1 and 20, and x is between 8 and 18. These products are commercially available from Arkema under the Noramox® brand and from Clariant under the Genamin® brand.

[0040] The polyether blocks may comprise polyoxyalkylene blocks having OH diol chain ends (known as polyether diols).

[0041] The polyether block is NH 2 It may contain polyoxyalkylene blocks with diamine chain ends. Such blocks can be obtained by cyanoacetylation of α,ω-dihydroxylated aliphatic polyoxyalkylene blocks. More particularly, commercial products of Jeffamine or Elastamine (e.g. Jeffamine® D400, D2000, ED 2003, XTJ 542, commercial products from Huntsman) may be used.

[0042] According to one embodiment, the polyether blocks in the copolymer are polyether diols.

[0043] The general method for the two-step preparation of PEBA copolymers having ester bonds between the PA and PE blocks is known and is described, for example, in French patent FR 2846332. The general method for the preparation of the PEBA copolymers of the invention containing amide bonds between the PA and PE blocks is known and is described, for example, in European patent EP 148 2011. The polyether blocks can be mixed with a polyamide precursor and a diacid chain limiter to prepare polymers having polyamide blocks and polyether blocks with randomly distributed units (one-step process).

[0044] It will be appreciated that the designation PEBA in the description of this invention may refer to Pebax® products sold by Arkema, Vestamid® products sold by Evonik®, Grilamid® products sold by EMS, as well as Kellaflex® products sold by DSM, or other PEBAs from other suppliers.

[0045] Advantageously, the PA block of the PEBA copolymer is chosen from PA 6, 11, 12, 612, 66 / 6, 1010, 614 and / or copolymers thereof, preferably PA 11, 12 and / or copolymers thereof, and / or the PE block of the PEBA copolymer is a PTMG block.

[0046] Advantageously, the PEBA used in the composition according to the invention is derived at least in part from bio-based feedstocks.

[0047] The term "renewably derived feedstock" or "bio-based feedstock" is understood to mean a material that contains bio-based carbon or carbon of renewable origin. In particular, a material that is composed of renewable starting materials, as opposed to a material obtained from fossil materials. 14C. "Renewably derived carbon content" or "bio-based carbon content" is determined by applying the standards ASTM D 6866 (ASTM D 6866-06) and ASTM D 7026 (ASTM D 7026-04). As an example, a PEBA based on polyamide 11 is at least partially derived from bio-based feedstocks and has a bio-based carbon content of at least 1%, which is at least 1.2×10 -14 of 12 C / 14 C isotope ratio. Preferably, the PEBA according to the present invention comprises at least 50% by weight of biobased carbon based on the total weight of carbon, which is at least 0.6×10 -12 of 12 C / 14 This content can be advantageously high, up to 100%, in particular in the case of PEBA containing PA11 blocks and PE blocks containing PO3G, PTMG and / or PPG derived from starting materials of renewable origin, which corresponds to the C isotope ratio. 12 C / 14 C isotope ratio 1.2×10 -12 is equivalent to.

[0048] The first polymeric material may comprise a PEBA content of 70% to 97% by weight, preferably 80% to 96% by weight, based on the weight of the first polymeric material. For example, this content may be 70% to 75%; or 75% to 80%; or 80% to 85%; or 85% to 90%; or 90% to 95%; or 95% to 97% by weight, based on the weight of the first polymeric material.

[0049] According to one embodiment, the first polymeric material comprises PEBA.

[0050] Advantageously, the PEBA copolymer has an instantaneous Shore D hardness of 30 or more, preferably 35 or more, and 80 Shore D or less, preferably 75 Shore D or less.

[0051] Instantaneous hardness measurements may be performed according to ISO standard 868:2003.

[0052] In some embodiments, the first polymeric material may include one or more additional polymers, which or these additional polymers may be selected from polyamides, which are preferably as described for the types of polyamide blocks above.

[0053] According to some embodiments, the first polymeric material does not include hollow glass beads.

[0054] Alternatively, the first polymeric material comprises hollow glass beads.

[0055] According to one embodiment, the first polymeric material may comprise a hollow glass bead content of 3% to 25% by weight, preferably 4% to 20% by weight, relative to the weight of the first polymeric material. For example, this content may be 3% to 5%; or 5% to 10%; or 10% to 15%; or 15% to 20%; or 20% to 25% by weight, relative to the weight of the first polymeric material.

[0056] Hollow glass beads are glass materials that are hollow (as opposed to solid) in structure.

[0057] The hollow glass beads may have a compressive strength, measured in glycerol according to ASTM D 3102-72 (1982), of at least 50 MPa, particularly preferably at least 100 MPa.

[0058] Hollow glass beads (hollow glass microspheres) usually have an aspect ratio (L / D ratio, where L represents the largest dimension of the bead cross-section and D the smallest dimension of the bead cross-section) of 0.85 to 1, in particular 0.90 to 1, preferably equal to 1. L and D can be measured by scanning electron microscopy (SEM).

[0059] The hollow glass beads are typically spherical or substantially spherical.

[0060] Advantageously, the hollow glass beads may have a volume average diameter D50, measured by laser diffraction method according to ASTM standard B 822-17, of between 10 and 80 μm, preferably between 13 and 50 μm.

[0061] The hollow glass beads may be surface treated, for example, with silanes (especially aminosilanes and epoxysilanes), polyamides, especially water-soluble polyamides, fatty acids, waxes, titanates, urethanes, polyhydroxyethers, epoxides, nickel or mixtures thereof. The hollow glass beads are preferably surface treated with aminosilanes, epoxysilanes, polyamides or mixtures thereof.

[0062] The hollow glass beads may be formed from borosilicate glass, preferably sodium carbonate-calcium oxide-borosilicate glass.

[0063] The hollow glass beads preferably have a density of 0.10 to 0.80 g / cm3, measured according to ASTM standard D 2840-69 (1976) using a gas pycnometer and helium as the measuring gas. 3 , preferably 0.30 to 0.77 g / cm 3 , particularly preferably 0.40 to 0.67 g / cm 3 The true density may be

[0064] According to a preferred embodiment, the hollow glass beads may contain zinc oxide having a content of 1.0% by weight or more relative to the total weight of the hollow glass beads, preferably 2.0% by weight or more relative to the total weight of the hollow glass beads.

[0065] Hollow glass beads suitable for the present invention may be Glass bubbles (registered trademark) sold by 3M Company, Winlight (registered trademark) sold by AXYZ Chemical Co, Ltd., Sphericel (registered trademark) sold by Potters, and SiLiBeads (registered trademark) sold by Sigmund-Linder.

[0066] The first polymeric material may also include one or more additives.

[0067] The first polymeric material may comprise an additive content of 0% to 5% by weight, preferably 0.1% to 4% by weight, relative to the weight of the first polymeric material. For example, this content may be 0% to 0.5%; or 0.5% to 1%; or 1% to 1.5%; or 1.5% to 2%; or 2% to 2.5%; or 2.5% to 3%; or 3% to 3.5%; or 3.5% to 4%; or 4% to 4.5%; or 4.5% to 5% by weight, relative to the weight of the first polymeric material.

[0068] The additives may be selected from fillers, dyes, stabilizers, plasticizers, surfactants, nucleating agents, pigments, gloss agents, antioxidants, lubricants, flame retardants, natural waxes, impact modifiers, laser marking additives, and mixtures thereof.

[0069] For example, the stabilizer may be a UV stabilizer, an organic stabilizer, or more generally a combination of organic stabilizers, such as phenolic antioxidants (e.g. Irganox® 245, 1098 or 1010 types from Ciba-BASF), phosphite antioxidants (e.g. Irgaphos® 126 from Ciba-BASF), possibly other stabilizers, such as HALS (short for Hindered Amine Light Stabilizer) (e.g. Tinuvin® 770 from Ciba-BASF), UV absorbers (e.g. Tinuvin® 312 from Ciba) or phosphorus stabilizers. Also amine antioxidants, such as Naugard 445 from Crompton, or multifunctional stabilizers, such as Nylostab S-EED from Clariant, may be used.

[0070] The stabilizer may also be an inorganic stabilizer, such as a copper-based stabilizer. Examples of such inorganic stabilizers include copper halides and copper acetate. Incidentally, other metals such as silver may also be considered as an option, but they are known to be less effective. These copper-based compounds are usually combined with halides of alkali metals, especially potassium.

[0071] By way of example, the plasticizer may be selected from benzenesulfonamide derivatives, such as n-butylbenzenesulfonamide (BBSA); ethyltoluenesulfonamide or N-cyclohexyltoluenesulfonamide; esters of hydroxybenzoic acid, such as 2-ethylhexyl para-hydroxybenzoate and 2-decylhexyl para-hydroxybenzoate; esters or ethers of tetrahydrofurfuryl alcohol, such as oligoethyleneoxytetrahydrofurfuryl alcohol; and esters of citric acid or hydroxymalonic acid, such as oligoethyleneoxymalonic acid.

[0072] By way of example, the fillers may be selected from silica, graphite, expanded graphite, carbon black, kaolin, magnesia, slag, talc, wollastonite, mica, nanofillers (carbon nanotubes), pigments, metal oxides (titanium oxide), metals, advantageously wollastonite and talc, preferentially talc.

[0073] By way of example, the impact modifier is a polyolefin having a modulus of elasticity of <200 MPa, in particular <100 MPa, measured according to the standard ISO 178:2010 at 23° C.

[0074] In one embodiment the impact modifier is selected from functionalized or non-functionalized polyolefins having a modulus of <200 MPa, in particular <100 MPa, and mixtures thereof.

[0075] Advantageously, the functionalized polyolefin has a functional group selected from maleic anhydride, carboxylic acid, carboxylic anhydride and epoxide functional groups, in particular ethylene / octene copolymers, ethylene / butene copolymers, ethylene / propylene elastomers (EPR), elastomeric ethylene / propylene / diene copolymers (EPDM) and ethylene / alkyl(meth)acrylate copolymers.

[0076] Exemplary additives for laser marking are: Iriotec® 8835 / Iriotec® 8850 from Merck, and Laser Mark® 1001074-E / Laser Mark® 1001088-E from Ampacet Corporation.

[0077] The first polymeric material may be in the form of a layer in the shaped article according to the invention.

[0078] Second Polymer Material The second polymeric material according to the invention comprises at least one thermoplastic polyurethane (TPU), which may be chosen from copolyether block urethanes and copolyester block urethanes.

[0079] The thermoplastic polyurethanes (TPUs) according to the invention are copolymers having hard and soft blocks. They result from the reaction of at least one polyisocyanate with at least one isocyanate-reactive compound, preferably having two isocyanate-reactive functional groups, more preferentially a polyol, and optionally a chain extender, optionally in the presence of a catalyst.

[0080] The rigid TPU block is a block consisting of units derived from polyisocyanates and chain extenders, the flexible block mainly comprises units derived from isocyanate-reactive compounds, preferably polyols, having a molar mass between 0.5 kg / mol and 100 kg / mol.

[0081] The polyisocyanates may be aliphatic, cycloaliphatic, araliphatic and / or aromatic. Preferably, the polyisocyanates are diisocyanates. Advantageously, the polyisocyanates are 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, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane. Isophorone diisocyanate, IPDI, 1,4-bis(isocyanatomethyl)cyclohexane, 1,3-bis(isocyanatomethyl)cyclohexane (HXDI), 2,4-paraphenylene diisocyanate (PPDI), 2,4-tetramethylene xylylene diisocyanate (TMXDI), 4,4'-, 2,4'- and / or 2,2'-dicyclohexylmethane diisocyanate (H12 The diisocyanate may be selected from the group consisting of 1,4-cyclohexane diisocyanate, 1-methyl-2,4- and / or 1-methyl-2,6-cyclohexane diisocyanate, 2,2'-, 2,4'- and / or 4,4'-diphenylmethane diisocyanate (MDI), 1,5-naphthylene diisocyanate (NDI), 2,4- and / or 2,6-toluene diisocyanate (TDI), diphenylmethane diisocyanate, 3,3'-dimethyldiphenyl diisocyanate, 1,2-diphenylethane diisocyanate, phenylene diisocyanate, methylene bis(4-cyclohexyl isocyanate) (HMDI) and mixtures thereof.

[0082] More preferably, the polyisocyanate is selected from the group consisting of diphenylmethane diisocyanate (MDI), toluene diisocyanate (TDI), pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), methylene bis(4-cyclohexylisocyanate) (HMDI), and mixtures thereof.

[0083] Even more preferably, the polyisocyanate is 4,4'-MDI (diphenylmethane-4,4'-diisocyanate), 1,6-HDI (hexamethylene-1,6-diisocyanate) or a mixture thereof.

[0084] The isocyanate-reactive compound preferably has an average functionality between 1.8 and 3, more preferably between 1.8 and 2.6, even more preferably between 1.8 and 2.2. The average functionality of the isocyanate-reactive compound corresponds to the number of isocyanate-reactive functional groups of the molecule theoretically calculated per molecule from the amount of compound. Preferably, the isocyanate-reactive compound has a number of Zerewitinoff active hydrogens within the above range according to a statistical average.

[0085] Preferably, the isocyanate-reactive compound, preferably a polyol, has a number average molar mass of 500 to 100000 g / mol. The isocyanate-reactive compound may have a number average molar mass of 500 to 8000 g / mol, more preferably 700 to 6000 g / mol, and even more particularly 800 to 4000 g / mol. In an embodiment, the isocyanate-reactive compound has a molecular weight of 500 to 600 g / mol, or 600 to 700 g / mol, or 700 to 800 g / mol, or 800 to 1000 g / mol, or 1000 to 1500 g / mol, or 1500 to 2000 g / mol, or 2000 to 2500 g / mol, or 2500 to 3000 g / mol, or 3000 to 3500 g / mol, or 3500 to 4000 g / mol, or 4000 to 5000 g / mol, or 5000 to 6000 g / mol, or 6000 to 7000 g / mol. 000 g / mol, or 7000 to 8000 g / mol, or 8000 to 10000 g / mol, or 10000 to 15000 g / mol, or 15000 to 20000 g / mol, or 20000 to 30000 g / mol, or 30000 to 40000 g / mol, or 40000 to 50000 g / mol, or 50000 to 60000 g / mol, or 60000 to 70000 g / mol, or 70000 to 80000 g / mol, or 80000 to 100000 g / mol. The number average molar mass can be determined by GPC, preferably according to ISO standard 16014-1:2012.

[0086] Advantageously, the isocyanate-reactive compound has at least one reactive group selected from hydroxyl, amine, thiol and carboxylic acid groups. Preferably, the isocyanate-reactive compound has at least one reactive hydroxyl group, more preferably a plurality of hydroxyl groups. Thus, particularly advantageously, the isocyanate-reactive compound consists of or comprises a polyol.

[0087] Preferably, the polyol is selected from the group consisting of polyester polyols, polyether polyols, polycarbonate diols, polysiloxane diols, polyalkylene diols and mixtures thereof. More preferably, the polyol is a polyether polyol, a polyester polyol and / or a polycarbonate diol, and the flexible blocks of the thermoplastic polyurethane are polyether blocks, polyester blocks and / or polycarbonate blocks, respectively. Also preferably, the flexible blocks of the thermoplastic polyurethane are polyether blocks and / or polyester blocks (the polyol is a polyether polyol and / or a polyester polyol).

[0088] The polyester polyols may include copolyesters based on polycaprolactone polyols and / or 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. More specifically, the copolyesters may be based on adipic acid and a mixture of 1,2-ethanediol and 1,4-butanediol, or the copolyesters may be based on adipic acid, succinic acid, pentanedioic acid, sebacic acid or mixtures thereof, and polytetrahydrofuran (tetramethylene glycol), or the copolyesters may be mixtures of these copolyesters.

[0089] As polyether polyols, polyether diols (i.e. aliphatic α,ω-dihydroxyl polyoxyalkylene blocks) are preferably used. Preferably, the polyether polyols are polyether diols based on ethylene oxide, propylene oxide and / or butylene oxide, block copolymers based on ethylene oxide and propylene oxide, polyethylene glycol, polypropylene glycol, polybutylene glycol, polytetrahydrofuran, polybutanediol or mixtures thereof. The polyether polyols are preferably polytetrahydrofuran (the flexible blocks of the thermoplastic polyurethane are therefore polytetrahydrofuran blocks) and / or polypropylene glycol (the flexible blocks of the thermoplastic polyurethane are therefore polypropylene glycol blocks) and / or polyethylene glycol (the flexible blocks of the thermoplastic polyurethane are therefore polyethylene glycol blocks), preferably polytetrahydrofuran with a number average molar mass of 500 to 15000 g / mol, preferably 1000 to 3000 g / mol. The polyether polyol may be a polyether diol which is the reaction product of ethylene oxide and propylene oxide, the molar ratio of ethylene oxide to propylene oxide being preferably from 0.01 to 100, more preferentially from 0.1 to 9, more preferentially from 0.25 to 4, more preferentially from 0.4 to 2.5, more preferentially from 0.6 to 1.5, more preferentially 1.

[0090] The polysiloxane diols that may be used in the present invention preferably have a number average molar mass of 500 to 15000 g / mol, preferably 1000 to 3000 g / mol. The number average molar mass may be determined by GPC, preferably according to ISO standard 16014-1:2012. Advantageously, the polysiloxane diol has the formula (I): HO-[RO] n -R-Si(R') 2 -[O-Si(R') 2 ] m-O-Si(R') 2 -R-[OR] p -OH (I) where R is preferably C 2 -C 4 alkylene, R' is preferably C 1 -C 4 alkyl, and each of n, m and p independently represents an integer between 0 and 50, m being more preferably from 1 to 50, and even more preferentially from 2 to 50. Preferably, the polysiloxane has the following formula (II): JPEG2025507731000002.jpg19170 [wherein Me is a methyl group] Or the following formula (III): JPEG2025507731000003.jpg19170. The polyalkylene diols that may be used in the present invention are preferably based on butadiene.

[0091] The polycarbonate diols that can be used in the present invention are preferably aliphatic polycarbonate diols. The polycarbonate diols are preferably based on alkane diols. They are preferably strictly difunctional. The preferred polycarbonate diols according to the present invention are based on butane diols, pentane diols and / or hexane diols, in particular 1,4-butane diol, 1,5-pentane diol, 1,6-hexane diol, 3-methylpentane-(1,5)-diol or mixtures thereof, more preferentially based on 1,4-butane diol, 1,5-pentane diol, 1,6-hexane diol or mixtures thereof. In particular, the polycarbonate diol may be a polycarbonate diol based on butanediol and hexanediol, a polycarbonate diol based on pentanediol and hexanediol, or a polycarbonate diol based on hexanediol, or a mixture of two or more of these polycarbonate diols. The polycarbonate diol advantageously has a number average molar mass ranging from 500 to 4000 g / mol, preferably from 650 to 3500 g / mol, more preferentially from 800 to 3000 g / mol. The number average molar mass may be determined by GPC, preferably according to ISO standard 16014-1:2012.

[0092] As isocyanate-reactive compounds, one or more polyols may be used.

[0093] Particularly preferably, the flexible blocks of the TPU are polytetrahydrofuran, polypropylene glycol and / or polyethylene glycol blocks.

[0094] Preferably, in addition to the isocyanate and the isocyanate-reactive compound, a chain extender is used in the preparation of the thermoplastic polyurethane.

[0095] The chain extender may be aliphatic, araliphatic, aromatic and / or cycloaliphatic. It advantageously has a number-average molar mass of 50 to 499 g / mol. The number-average molar mass may be determined by GPC, preferably according to ISO standard 16014-1:2012. The chain extender preferably has two isocyanate-reactive groups (also called "functional groups"). It is possible to use a single chain extender or a mixture of at least two chain extenders.

[0096] The chain extender is preferably difunctional. Examples of chain extenders are diamines and alkanediols having 2 to 10 carbon atoms. In particular, the chain extender may be selected 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-dimethanolcyclohexane, neopentyl glycol, hydroquinone bis(beta-hydroxyethyl)ether (HQEE), di-, tri-, tetra-, penta-, hexa-, hepta-, octa-, nona- and / or deca-alkylene glycols, their respective oligomers, polypropylene glycol, and mixtures thereof. More preferentially, the chain extender is selected from the group consisting of 1,2-ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol and mixtures thereof, more preferably selected from 1,3-propanediol, 1,4-butanediol and / or 1,6-hexanediol. Even more preferentially, the chain extender is a mixture of 1,4-butanediol and 1,6-hexanediol, more preferentially in a molar ratio of 6:1 to 10:1.

[0097] Advantageously, a catalyst is used in the synthesis of the thermoplastic polyurethane, which makes it possible to promote the reaction of the NCO groups of the polyisocyanate with the isocyanate-reactive compounds, preferably with the hydroxyl groups of the isocyanate-reactive compounds, and, if present, with the chain extenders.

[0098] The catalyst is preferably a tertiary amine, more preferentially selected from triethylamine, dimethylcyclohexylamine, N-methylmorpholine, N,N'-dimethylpiperazine, 2-(dimethylaminoethoxy)ethanol and / or diazabicyclo-(2,2,2)-octane. Alternatively or additionally, the catalyst is an organometallic compound such as a titanate, an iron compound, preferably iron(II) acetylacetonate, a tin compound, preferably a carboxylic acid, more preferentially tin diacetate, tin dioctoate, tin dilaurate or a dialkyltin salt, preferably dibutyltin diacetate and / or dibutyltin dilaurate, a bismuth carboxylate, preferably bismuth decanoate, or a mixture thereof.

[0099] More preferably, the catalyst is selected from the group consisting of tin dioctoate, bismuth decanoate, titanates and mixtures thereof. More preferably, the catalyst is tin dioctoate.

[0100] During the preparation of thermoplastic polyurethane, the molar ratio of isocyanate-reactive compound and chain extender can be changed to adjust the hardness and melt flow index of TPU. Specifically, when the proportion of chain extender increases, the hardness and melt viscosity of TPU increases, and the melt flow index of TPU decreases. To produce flexible TPU, preferably TPU with Shore A hardness of less than 95, more preferentially 75 to 95, isocyanate-reactive compound and chain extender can be used in a molar ratio of 1:1 to 1:5, preferably 1:1.5 to 1:4.5, so that the mixture of isocyanate-reactive compound and chain extender has a hydroxyl equivalent weight of more than 200, more specifically 230 to 650, even more preferentially 230 to 500. To produce harder TPUs, preferably with a Shore A hardness of more than 98, preferably a Shore D hardness of from 55 to 75, the isocyanate-reactive compound and the chain extender may be used in a molar ratio of from 1:5.5 to 1:15, preferably from 1:6 to 1:12, such that the mixture of isocyanate-reactive compound and chain extender has a hydroxyl equivalent weight of from 110 to 200, more preferentially from 120 to 180.

[0101] Advantageously, to prepare the TPU, the polyisocyanate, the isocyanate-reactive compound and preferably the chain extender are reacted, preferably in the presence of a catalyst, in amounts such that the equivalent ratio of NCO groups of the polyisocyanate to the sum of the hydroxyl groups of the isocyanate-reactive compound and the chain extender is from 0.95:1 to 1.10:1, preferably from 0.98:1 to 1.08:1, more preferably from 1:1 to 1.05:1. The catalyst is advantageously present in an amount of from 0.0001 to 0.1 parts by weight per 100 parts by weight of the TPU synthesis reagents.

[0102] The TPU according to the invention preferably has a weight average molar mass of 10000 g / mol or more, preferably 40000 g / mol or more, more preferably 60000 g / mol or more.Preferably, the weight average molar mass of the TPU is 80000 g / mol or less.The weight average molar mass can be determined by gel permeation chromatography (GPC).

[0103] Advantageously, the TPU is semi-crystalline. Its melting temperature Tm is preferably between 100° C. and 230° C., more preferably between 120° C. and 200° C. The melting temperature can be measured according to ISO standard 11357-3 Plastics - Differential scanning calorimetry (DSC) Part 3.

[0104] Advantageously, the TPU may be a recycled TPU and / or a partially or fully bio-based TPU.

[0105] Preferably, the TPU has a Shore D hardness of less than or equal to 75 D, more preferentially less than or equal to 65 D. In particular, the TPU used in the present invention may have a hardness of 65 Shore A to 70 Shore D, preferably 75 Shore A to 60 Shore D. The measurement of hardness may be carried out according to ISO standard 7619-1.

[0106] The second polymeric material may comprise a single TPU (as described above) or several of these TPUs as a mixture.

[0107] The second polymeric material may comprise a TPU content of 70% to 97% by weight, preferably 80% to 96% by weight, relative to the weight of the second polymeric material. For example, this content may be 70% to 75%; or 75% to 80%; or 80% to 85%; or 85% to 90%; or 90% to 95%; or 95% to 97% by weight, relative to the weight of the second polymeric material.

[0108] According to some embodiments, the second polymeric material may also include at least one thermoplastic elastomer (TPE) polymer different from the thermoplastic polyurethane (TPU), which may be selected from PEBA (as described above), copolyether block esters (CoPEs), and combinations thereof.

[0109] A CoPE comprises at least one polyether (PE) block and at least one polyester PES (homopolymer or copolyester) block.

[0110] The polyester blocks can be obtained by polycondensation of carboxylic acids such as isophthalic acid or terephthalic acid, or bio-based carboxylic acids such as furandicarboxylic acid, with glycols such as ethylene glycol, trimethylene glycol, propylene glycol or tetramethylene glycol by esterification. The polyether blocks can be as described above in the description of PEBA.

[0111] The second polymeric material includes hollow glass beads.

[0112] Thus, the hollow glass beads may be present only in the second polymeric material or in the first and second polymeric materials.

[0113] The hollow glass beads are as described above.

[0114] The second polymeric material may comprise a hollow glass bead content of 3% to 25% by weight, preferably 4% to 20% by weight, relative to the weight of the second polymeric material. For example, this content may be 3% to 5%; or 5% to 10%; or 10% to 15%; or 15% to 20%; or 20% to 25% by weight, relative to the weight of the second polymeric material.

[0115] According to a preferred embodiment, the hollow glass beads may contain zinc oxide having a content of 1.0% by weight or more relative to the total weight of the hollow glass beads, preferably 2.0% by weight or more relative to the total weight of the hollow glass beads.

[0116] The second polymeric material may also include one or more additives, which are as described above in relation to the first material.

[0117] The second polymeric material may comprise an additive content of 0% to 5% by weight, preferably 0.1% to 4% by weight, relative to the weight of the second polymeric material. For example, this content may be 0% to 0.5%; or 0.5% to 1%; or 1% to 1.5%; or 1.5% to 2%; or 2% to 2.5%; or 2.5% to 3%; or 3% to 3.5%; or 3.5% to 4%; or 4% to 4.5%; or 4.5% to 5% by weight, relative to the weight of the second polymeric material.

[0118] The second polymeric material may be in the form of a layer in the shaped article according to the invention.

[0119] The molded article according to the invention may also comprise one or more additional layers of material.

[0120] According to one embodiment, the molded article of the present invention comprises: 60-95% by weight of a first polymeric material and a second polymeric material; 3 to 25% by weight of hollow glass beads; 0-10 wt. % of one or more additives; Including, The total amount is 100% by weight of the molded article.

[0121] Adhesion method The present invention also relates to a method for directly adhering a first polymeric material as described above to a second polymeric material as described above.

[0122] According to one embodiment, a first polymeric material is melted or softened under heat and this molten material is contacted with at least a portion of a second polymeric material to bond the two materials together.

[0123] According to another embodiment, a first polymeric material and a second polymeric material are independently melted or softened under heat, and the molten first polymeric material is contacted with at least a portion of the molten second polymeric material to bond the two materials together.

[0124] Advantageously, in the assembly method according to the invention, the first polymeric material and the second polymeric material are assembled by a direct adhesion method selected from overmolding, hot pressing, coextrusion, thermoforming, injection molding, extrusion molding, blow molding, and combinations thereof; preferably, by overmolding.

[0125] According to one embodiment, the method involves overmolding a first polymeric material, with or without hollow glass beads, onto a second polymeric material that includes hollow glass beads.

[0126] According to one embodiment, the hollow glass beads contain zinc oxide having a content of 1.0% by weight or more relative to the total weight of the hollow glass beads, preferably 2.0% by weight or more relative to the total weight of the hollow glass beads.

[0127] Advantageously, the assembly temperature of the direct bonding method according to the invention is between 220 and 300°C, preferably between 240 and 290°C, and more preferably between 250 and 290°C.

[0128] Such a method can be carried out, for example, by joining a first polymeric material and a second polymeric material in an injection molding method, in particular a two-material injection molding method, a two-color injection molding method, a multi-color injection molding method, a two-injection molding method or a co-injection molding method. Other conventional methods may be used: thermoforming, hot press molding, insert molding, sandwich injection molding, extrusion molding, in particular co-extrusion molding, injection blow molding and other methods for processing TPE materials. The skilled person will select the type of injection molding machine depending on the type of mold, the insert and the material to be injected.

[0129] According to one particular embodiment of the hot press molding, the first and second polymeric materials are loaded into the mold in the form of granules, powder or other form. According to another embodiment, the first and second polymeric materials are loaded into the mold in the form of preforms.

[0130] According to yet another embodiment of insert injection molding, a molded composite part may be produced by molding a second polymeric material using a method such as injection molding, extrusion, particularly sheet molding, or film molding; then inserting or forming the molded part thus formed into a mold; and then injecting the as yet unmolded first polymeric material into the space or cavity between the molded part and the mold. In insert injection molding, the molded part to be inserted into the mold is preferably preheated in the mold. EXAMPLES

[0131] The following examples illustrate the invention without limiting it.

[0132] Materials used: - PEBA1: a copolymer containing PA11 blocks and PTMG blocks and having an instantaneous hardness of 53 Shore D. - TPU1: commercial product Elastollan® 1195A (BASF) - copolyether block urethane, 95 Shore A. - TPU2: Commercially available Pearlthane® ECO 12T95 (Lubrizol) - copolyester block urethane, 95 Shore A. - R1: Hollow glass beads, density 0.60g / cc, D50=30μm, ZnO content is about 3%, compressive strength is 125MPa.

[0133] In the context of the present invention, the adhesion between two polymeric materials is expressed by the peel strength in kgf / cm, measured according to ISO standard 11339.

[0134] Example 1 Various second polymeric materials (SPM) were prepared as shown in Table 1. The SPM compositions in Table 1 were prepared by melt mixing TPU granules with hollow glass beads and stabilizing additives (antioxidants). The mixing was carried out by compounding in a co-rotating twin screw extruder with a diameter of 26 mm and a flat temperature (T°) profile of 185°C. The screw speed is 250 rpm and the throughput is 15 kg / h. The TPU and additives are introduced in the main hopper. The hollow glass beads are introduced by a side feed.

[0135] The composition was then molded into a plate having a thickness of 2 mm using an injection molding machine (manufactured by Toshiba) at a set temperature of 220° C. and a mold temperature of 20° C. The insert plate thus prepared was placed in a mold for overmolding having a thickness of 4 mm. JPEG2025507731000004.jpg34170

[0136] PEBA1 was then overmolded onto the various SPM1 to 6 inserts at an assembly temperature of 260°C and a molding temperature of 60°C.

[0137] The overmolded parts thus prepared were cut into strips 20 mm wide and subjected to peel tests at a separation speed of 100 mm / min according to ISO standard 11339. The results of these tests are shown in Table 2 below.

[0138] The following table compares the adhesion (peel strength, kgf / cm) of PEBA1 (first polymer material) and SPM1-6 inserts (second polymer material) after direct bonding by overmolding. JPEG2025507731000005.jpg18170

[0139] The first polymer material, PEBA1, was found to have improved adhesion to the second polymer materials (SPM2, SPM3, SPM5, SPM6) that was equal to or better than the second polymer materials that did not contain hollow glass beads (SPM1 and SPM4).

[0140] The density of the overmolded parts was measured according to ISO standard 1183-3:1999 (Table 3). JPEG2025507731000006.jpg18170

[0141] It was found that the density of the overmolded articles containing hollow glass beads was reduced compared to the overmolded articles not containing hollow glass beads (SPM1-PEBA1 and SPM4-PEBA1).

[0142] Example 2 In this example, peel tests were carried out with second polymeric materials SPM1 and SPM3 (described in Example 1) as inserts overmolded with first polymeric materials FPM1, FPM2 or FPM3. Compositions FPM1 to FPM3 in Table 4 were prepared by melt mixing PEBA granules with hollow glass beads and stabilizing additives (antioxidants). The mixing was carried out by compounding in a co-rotating twin screw extruder with a diameter of 26 mm and a flat temperature (T°) profile of 250° C. The screw speed is 250 rpm and the throughput is 20 kg / h. PEBA and additives are introduced into the main hopper. Hollow glass beads are introduced by side feed.

[0143] The compositions were then overmolded onto inserts of the different materials SPM1 and SPM3 in the form of plates with a thickness of 2 mm at a set temperature of 260°C and a mould temperature of 60°C.

[0144] The overmolded parts thus prepared were cut into strips of width 20 mm and peel tested according to ISO standard 11339 at a separation speed of 100 mm / min. JPEG2025507731000007.jpg50170

[0145] The following Table 5 compares the adhesion (peel strength, kgf / cm) of FPM1 and FPM3 with SPM1 and SPM3 inserts after direct bonding by overmolding. JPEG2025507731000008.jpg23170

[0146] The density of the overmolded parts was measured according to ISO standard 1183-3:1999 (Table 6). JPEG2025507731000009.jpg23170

[0147] It was found that the density of the overmolded parts containing hollow glass beads was reduced compared to the overmolded parts not containing hollow glass beads (SPM1-FPM1).

[0148] It has been found that even when hollow glass beads are present in the first and second polymeric materials, the present invention makes it possible to obtain molded articles with lower density and similar or improved adhesion between the materials compared to (first or second) polymeric materials that do not contain hollow glass beads.

[0149] Example 3 (Counter Example) In this example, a peel test was carried out using a first polymer material FPM1 (described in Example 2) as an insert overmolded with a second polymer material SPM3 (described in Example 1). The composition was then overmolded onto the FPM1 insert in the form of a 2 mm thick plate at a set temperature of 230° C. and a mold temperature of 60° C.

[0150] The overmolded parts thus prepared were cut into strips of width 20 mm and peel tested according to ISO standard 11339 at a separation speed of 100 mm / min.

[0151] The adhesion (peel strength, kgf / cm) of SPM3 overmolded onto FPM1 inserts was measured to be 4 kgf / cm, significantly lower than that of FPM1 overmolded onto SPM3 inserts (≥20, Table 2).

Claims

1. A molded article comprising a first polymeric material comprising at least one copolymer comprising polyamide blocks and polyether blocks (PEBA) and a second polymeric material comprising at least one thermoplastic polyurethane (TPU), wherein the first polymeric material directly adheres to the second polymeric material, and the second polymeric material comprises hollow glass beads.

2. 2. The molded article according to claim 1, wherein the adhesive strength between the two polymeric materials, expressed as a peel strength in kgf / cm, is 10 kgf / cm or more, preferably 12 kgf / cm or more.

3. 2. The molded article of claim 1, wherein the PEBA copolymer has an instantaneous Shore D hardness of 30 or more, preferably 35 or more, and 80 Shore D or less, preferably 75 Shore D or less.

4. 2. The molded article according to claim 1, wherein the PA blocks of the PEBA copolymer are selected from PA 6, 11, 12, 612, 66 / 6, 1010, 614, and / or copolymers thereof, preferably PA 11, 12 and / or copolymers thereof, and / or the PE blocks of the PEBA copolymer are PTMG blocks.

5. 2. The molded article according to claim 1, wherein the hollow glass beads have a content of 3% to 25% by weight based on the total weight of the second polymeric material.

6. 10. The molded article of claim 1, wherein the first polymeric material comprises a hollow glass bead content of 3% to 25% by weight, based on the weight of the first polymeric material.

7. 2. The molded article according to claim 1, wherein the hollow glass beads contain zinc oxide in an amount of 1.0% by weight or more relative to the total weight of the hollow glass beads, preferably 2.0% by weight or more relative to the total weight of the hollow glass beads.

8. 60 to 95% by weight of a first polymeric material and a second polymeric material; 3 to 25 wt. % hollow glass beads; 0-10 wt. % of one or more additives; Including, They total 100% by weight of the molded article. The molded article according to claim 1.

9. 10. Use of the molded article according to claim 1 for the production of sports goods, shoe materials, personal protective equipment, automotive parts, construction parts, optical equipment parts, electrical and electronic equipment parts, medical equipment parts such as catheters, or power transmission belts or conveyor belts.

10. 1. A method for directly bonding a first polymeric material comprising at least one copolymer comprising polyamide blocks and polyether blocks to a second polymeric material comprising at least one thermoplastic polyurethane and hollow glass beads, characterized in that the assembly is carried out by a method comprising heating the first polymeric material, and the material, melted or softened under heating, is brought into contact with at least a portion of the second polymeric material so as to bond the two materials together.

11. 11. The method of claim 10, wherein the first polymeric material and the second polymeric material are assembled by a direct bonding method selected from overmolding, hot pressing, co-extrusion, thermoforming, injection molding, extrusion molding, blow molding, and combinations thereof; preferably by overmolding one material onto the other.

12. 11. The method of claim 10, wherein the method is a method of overmolding a first polymeric material onto a second polymeric material comprising hollow glass beads.

13. 11. The method according to claim 10, wherein the hollow glass beads contain zinc oxide having a content of 1.0% by weight or more relative to the total weight of the hollow glass beads, preferably 2.0% by weight or more relative to the total weight of the hollow glass beads.

14. 11. The method according to claim 10, wherein the assembly temperature is in the range of 220 to 300°C, preferably 240 to 290°C, preferably 250 to 290°C.