Foaming polymer composition containing a branched copolymer containing polyamide blocks and polyether blocks

Abstract

The present invention relates to a foamable composition comprising an ethylene-vinyl acetate (EVA) copolymer and / or a copolymer of ethylene and an alkyl (meth)acrylate and a branched copolymer containing a polyamide block and a polyether block, a method for producing said composition, and the use of said composition. The present invention also relates to a foam, a method for producing said foam, and the use of said foam.

Description

[Technical Field]

[0001] The present invention relates to a foaming composition comprising an ethylene-vinyl acetate (EVA) copolymer and / or a copolymer of ethylene and alkyl (meth)acrylate, as well as a branched copolymer containing a polyamide block and a polyether block, a method for producing the composition, and the use of the composition. The present invention also relates to a foam, a method for producing the foam, and the use of the foam. [Background technology]

[0002] Various foams based on EVA copolymers are used in the field of sports equipment, particularly in soles or sole components, gloves, rackets or golf balls, and personal protective equipment for sports (jackets, helmet internal components, shells, etc.). Such applications require a specific set of physical properties that ensure resilience, low compressive strain, and the ability to withstand repeated impacts without deformation and return to their original shape.

[0003] Numerous cross-linked EVA foams have been developed using chemical blowing agents for shoe applications. However, these EVA foams have limitations in terms of flexibility, elasticity, a relatively narrow operating temperature range, relatively low stretchability, and less-than-ideal durability. Furthermore, these foams undergo significant shrinkage regardless of the process used to obtain them.

[0004] International Publication No. 2013 / 192581 describes an EVA foam containing a polyolefin elastomer and an olefin block copolymer.

[0005] U.S. Patent Application Publication No. 2017 / 0267849 describes a pre-foamed composition comprising a partially hydrogenated thermoplastic elastomer block copolymer, an olefin block copolymer, and EVA. The partially hydrogenated thermoplastic elastomer block copolymer is an ABA or AB copolymer in which block A contains styrene units and block B is a random copolymer of ethylene and olefin.

[0006] However, it has been found that obtaining a foam that combines low-density properties with good elasticity is difficult. This is because, generally, an improvement in mechanical properties is observed with increasing density, or conversely, a decrease in density negatively affects mechanical properties, especially elasticity.

[0007] There is a need to provide a composition that reduces shrinkage after molding of the foam, enabling the production of a lighter polymer foam while maintaining good elasticity and rigidity. [Overview of the project]

[0008] The present invention, firstly, • A copolymer (a) selected from ethylene-vinyl acetate (EVA) copolymer, copolymer of ethylene and alkyl (meth)acrylate and / or mixtures thereof, • Branched copolymer (b) (branched PEBA copolymer) containing polyamide block and polyether block, • A crosslinking agent, preferably a peroxide, This relates to a composition containing the following:

[0009] According to one embodiment, the polymer composition according to the present invention comprises copolymer (a) in an amount of 30% to 99.9%, typically 50% to 99.9%, preferably 60% to 99.9%, and more preferably 70% to 99.9%, based on the total weight of the composition.

[0010] According to one embodiment, the composition contains 0.1% to 50%, preferably 0.1% to 40%, of the weight of the branched PEBA copolymer, based on the total weight of the composition. Preferably, the composition contains 0.1% to 30%, or 0.5% to 30%, or 1% to 25%, or 1% to 20%, of the weight of the PEBA copolymer (b), based on the total weight of the composition.

[0011] The composition typically contains 0.01% to 2% by weight of a crosslinking agent, preferably a peroxide, relative to the total weight of the composition.

[0012] According to one embodiment, the composition contains an additive at a weight of 0.1% to 20% of the total weight of the composition.

[0013] According to one embodiment, the composition further comprises a foaming agent in an amount of 0.5% to 10%, preferably 0.5% to 8%, relative to the total weight of the composition.

[0014] According to one embodiment, the composition of the present invention may further comprise a polyolefin (c) and / or a thermoplastic elastic polymer (d).

[0015] According to one embodiment, the composition of the present invention is • A copolymer (a) selected from ethylene-vinyl acetate (EVA) copolymer, copolymer of ethylene and alkyl (meth)acrylate and / or mixtures thereof, • A branched copolymer (b) containing polyamide blocks and polyether blocks, having a number-average functional value (Efn) greater than 2, preferably 3 or more, Depending on the circumstances, polyolefin (c) and / or thermoplastic elastic polymer (d), • A crosslinking agent, preferably a peroxide, Includes.

[0016] According to one embodiment, the composition is • A copolymer (a) selected from ethylene-vinyl acetate (EVA) copolymers, copolymers of ethylene and alkyl (meth)acrylates and / or mixtures thereof, in a weight of 30% to 99.9%, typically 50% to 99.9%, preferably 60% to 99.9%, and more preferably 70% to 99.9%, • A branched copolymer (b) containing 0.1% to 40%, preferably 0.1% to 30%, of polyamide blocks and polyether blocks by weight, wherein the number-average functional value (Efn) is greater than 2, preferably 3 or more. • 0% to 50%, preferably 0.1% to 40%, or 0.1% to 30%, or 0.1% to 20% of polyolefin (c) and / or thermoplastic elastic polymer (d) relative to the total weight of the composition, · containing a crosslinking agent of 0.01% to 2% by weight, preferably a peroxide, with the total being 100% by weight.

[0017] Preferably, the composition contains a polyolefin (c) and / or a thermoplastic elastomeric polymer (d) of 0.1% to 50% by weight, preferably 0.1% to 40% by weight, or 0.1% to 30% by weight, or 0.1% to 20% by weight, based on the total weight of the composition.

[0018] The polyolefin (c) may be functionalized or non-functionalized, or may be a mixture of at least one functionalized and / or at least one non-functionalized species. The polyolefin (c) is preferably a functionalized polyolefin (c1).

[0019] The thermoplastic elastomeric polymer (d) can typically be selected from copolymers containing polyester blocks and polyether blocks, linear copolymers (PEBA) containing polyamide blocks and polyether blocks, polyurethanes, olefinic thermoplastic elastomers or olefinic block copolymers, styrene-diene block copolymers, and / or mixtures thereof.

[0020] The present invention also relates to a method for preparing the above composition, (i) · a copolymer (a), · a copolymer (b), · a crosslinking agent, preferably a peroxide, · optionally, a polyolefin (c), a thermoplastic elastomeric polymer (d), and at least one additive, providing a mixture containing them, (ii) molding the mixture by injection molding, compression / molding or extrusion, relates to a method including these.

[0021] The above steps can be carried out separately or simultaneously. The steps of the preparation method can be carried out with items of the same equipment, such as a mixer or an extruder.

[0022] The composition according to the present invention may be in the form of granules, rods, extruded sheets, or extruded or injection-molded parts.

[0023] According to one embodiment, step (i) is: The total weight equals 100% of the mixture. • Copolymer (a) of 30% to 99.9% by weight, typically 50% to 99.9%, preferably 60% to 99.9%. • Copolymer (b) in an amount of 0.1% to 50% by weight, typically 0.1% to 40%, preferably 0.1% to 30%. • 0% to 50% by weight of polyolefin (c) and / or thermoplastic elastic polymer (d), • At least one additive in an amount of 0% to 20% by weight, preferably 0.1% to 20%. • 0.01% to 2% by weight of a crosslinking agent, preferably a peroxide. This is typically done by mixing the materials in a molten state.

[0024] According to one embodiment, the present invention relates to a crosslinked foam formed based on the above composition.

[0025] The present invention also provides a method for preparing a foam, (i) • Copolymer (a), • Copolymer (b), • A crosslinking agent, preferably a peroxide, • A foaming agent, preferably a chemical foaming agent, Depending on the circumstances, a polyolefin (c), a thermoplastic elastic polymer (d), and at least one additive, A step of providing a mixture containing, (ii) A step of molding the mixture by injection molding, compression / molding or extrusion, (iii) A step of foaming the mixture, This includes methods.

[0026] The above steps can be performed separately or simultaneously.

[0027] According to one embodiment, steps (i)+(ii), (ii)+(iii), or (i)+(ii)+(iii) are performed simultaneously.

[0028] The preparation process can be carried out using the same equipment, such as a mixer or an extruder.

[0029] According to one embodiment, step (i) is: The total weight equals 100% of the mixture. • Copolymer (a) of 30% to 99.9% by weight, typically 50% to 99.9%, preferably 60% to 99.9%. • Copolymer (b) in an amount of 0.1% to 50% by weight, typically 0.1% to 40%, preferably 0.1% to 30%. • 0% to 50% by weight of polyolefin (c) and / or thermoplastic elastic polymer (d), • At least one additive in an amount of 0% to 20% by weight, preferably 0.1% to 20%. • 0.01% to 2% by weight of a crosslinking agent, preferably a peroxide. • 0.5% to 10% by weight of a blowing agent, preferably a chemical blowing agent. This is done by mixing the materials in a molten state.

[0030] According to another variant, the blowing agent is introduced during and / or after step (ii). The amount of blowing agent introduced into the method is typically 0.5% to 10% by weight relative to the total weight of the mixture.

[0031] In this case, the mixture introduced in step (i) is the composition defined above.

[0032] The present invention also relates to compositions or foams that can be obtained according to the above method.

[0033] The method of the present invention makes it possible to prepare a polymer foam that is regular, uniform, and has the above-mentioned advantageous properties.

[0034] Accordingly, the present invention provides a foam having low density, uniformity and regularity, high ability to recover elastic energy under low stress load, low compressive strain (and therefore improved durability), high rebound elasticity, and improved elastic properties, as described above.

[0035] This is achieved by introducing a specific PEBA copolymer into a cross-linked foam of ethylene-vinyl acetate (EVA) and / or ethylene and alkyl (meth)acrylate.

[0036] Typically, the foam obtained at the end of the above preparation method is • A (co)polymer that forms the polymer matrix of the foam, • Decomposition products and / or by-products generated from at least one blowing agent and at least one crosslinking agent and optionally at least one additive, which are dispersed and located in the polymer matrix, It essentially consists of or comprises.

[0037] The present invention relates to the use of the above-mentioned compositions or foams for the manufacture of articles, preferably shoe soles.

[0038] The present invention also relates to an article comprising or containing at least one element of the above-mentioned composition or foam.

[0039] The items can be selected from, in particular, sports shoe soles, large or small balls, gloves, personal protective equipment, rail pads, automotive parts, building components, and electrical and electronic equipment components.

[0040] Next, the present invention will be described in more detail. [Modes for carrying out the invention]

[0041] copolymer(a) The copolymer (a) according to the present invention is a copolymer selected from ethylene-vinyl acetate (EVA) copolymers, copolymers of ethylene and alkyl (meth)acrylate, and / or mixtures thereof.

[0042] The relative amount of vinyl acetate comonomer incorporated into the EVA copolymer may range from 0.1% to 40% or more by weight of the entire copolymer. For example, EVA may have a vinyl acetate content of 2% to 50%, 5% to 40%, or 10% to 30% by weight. EVA can be modified by methods well known to those skilled in the art, including modification with maleic anhydride or an unsaturated carboxylic acid such as maleic acid or its derivatives.

[0043] Copolymers of ethylene and alkyl (meth)acrylate contain repeating units derived from ethylene and alkyl acrylate, alkyl methacrylate, or combinations thereof, where the alkyl fragment contains 1 to 8 carbon atoms. Examples of alkyl include methyl, ethyl, propyl, butyl, or combinations of two or more of these. Alkyl (meth)acrylate comonomers may be incorporated into the ethylene / alkyl (meth)acrylate copolymer in amounts of 0.1% to 45% by weight or more of the total copolymer. Alkyl groups can contain 1 to about 8 carbon atoms. For example, alkyl (meth)acrylate comonomers can be present in the copolymer in amounts of 5% to 45%, 10% to 35%, or 10% to 28% by weight. Examples of ethylene-alkyl (meth)acrylate copolymers include ethylene / methyl acrylate, ethylene / ethyl acrylate, ethylene / butyl acrylate, or combinations of two or more of these. Mixtures of two or more different ethylene-alkyl (meth)acrylate copolymers can be used.

[0044] Copolymer (a) may have a melt flow index (MFI) of 0.1 to 60 g / 10 min or 0.3 to 30 g / 10 min. Preferably, copolymer (a) has a low melt flow index, for example, 0.1 to 20, or 0.5 to 20, or 0.5 to 10, or 0.1 to 5 g / 10 min.

[0045] In the context of this invention, unless otherwise specified, the melt flow index (MFI) was measured at a temperature of 190°C under a load of 2160 grams (expressed in units of g / 10 min) according to the ISO 1133 standard.

[0046] Copolymer (b) Branched PEBA copolymers generally have an instantaneous hardness of 72 Shore D or less, more preferably 68 Shore D or less, or 55 Shore D or less, or 45 Shore D or less. Hardness measurement can be performed according to the standard ISO 868:2003.

[0047] Three types of polyamide blocks can be used advantageously.

[0048] According to the first type, the polyamide block is derived from the condensation of a dicarboxylic acid, particularly one containing 4 to 36 carbon atoms, preferably one containing 6 to 18 carbon atoms, and a diamine, particularly one containing 2 to 20 carbon atoms, preferably one containing 5 to 14 carbon atoms.

[0049] Examples of dicarboxylic acids include 1,4-cyclohexanedicarboxylic acid, butanediic acid, adipic acid, azelaic acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, terephthalic acid, and isophthalic acid, as well as dimerized fatty acids.

[0050] Examples of diamines include isomers of tetramethylenediamine, hexamethylenediamine, 1,10-decamethylenediamine, dodecamethylenediamine, trimethylhexamethylenediamine, bis(4-aminocyclohexyl)methane (BACM), bis(3-methyl-4-aminocyclohexyl)methane (BMACM), and 2,2-bis(3-methyl-4-aminocyclohexyl)propane (BMACP), para-aminodicyclohexylmethane (PACM), isophoronediamine (IPDA), 2,6-bis(aminomethyl)norbornane (BAMN), and piperazine (Pip).

[0051] Advantageously, polyamide blocks PA4.12, PA4.14, PA4.18, PA6.10, PA6.12, PA6.14, PA6.18, PA9.12, PA10.10, PA10.12, PA10.14, and PA10.18 are used. In notation PAX.Y, X represents the number of carbon atoms derived from the diamine residue, as in the conventional method, and Y represents the number of carbon atoms derived from the diacid residue.

[0052] According to the second type, the polyamide block is obtained from the condensation of one or more α,ω-aminocarboxylic acids and / or one or more lactams containing 6 to 12 carbon atoms in the presence of a dicarboxylic acid or diamine containing 4 to 12 carbon atoms. Examples of lactams include caprolactam, oenantractam, and lauryllactam. Examples of α,ω-aminocarboxylic acids include aminocaproic acid, 7-aminoheptanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid.

[0053] Advantageously, the second type of polyamide block is the PA11 (polyundecaneamide), PA12 (polydodecaneamide), or PA6 (polycaprolactam) block. In the notation PAX, X represents the number of carbon atoms derived from amino acid residues.

[0054] According to the third type, the polyamide block is obtained from the condensation of at least one α,ω-aminocarboxylic acid (or lactam), at least one diamine, and at least one dicarboxylic acid.

[0055] In this case, the polyamide PA block is • A linear aliphatic or aromatic diamine containing X carbon atoms, • A dicarboxylic acid containing Y carbon atoms, Selected from lactams and α,ω-aminocarboxylic acids containing Z carbon atoms, and equimolar mixtures of at least one diamine containing X1 carbon atoms and at least one dicarboxylic acid containing Y1 carbon atoms, where (X1, Y1) is different from (X, Y), comonomer {Z}, Prepared by condensation, The comonomer {Z} is introduced in a weight proportion of up to 50%, preferably up to 20%, and more preferably up to 10%, relative to the total amount of the polyamide precursor monomer. This is in the presence of a chain-limiting agent selected from dicarboxylic acids.

[0056] Advantageously, a dicarboxylic acid containing Y carbon atoms is used as a chain limiting agent that is introduced in excess of the diamine's stoichiometry.

[0057] According to one variant of this third type, the polyamide block arises from the condensation of at least two α,ω-aminocarboxylic acids, or at least two lactams containing 6 to 12 carbon atoms, or one aminocarboxylic acid having no equal number of carbon atoms to one lactam, in the presence of an optional chain restrictor. Examples of aliphatic α,ω-aminocarboxylic acids include aminocaproic acid, 7-aminoheptanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Examples of lactams include caprolactam, oenantractam, and lauryllactam. Examples of aliphatic diamines include hexamethylenediamine, dodecamethylenediamine, and trimethylhexamethylenediamine. An example of alicyclic diacid is 1,4-cyclohexanedicarboxylic acid. Examples of aliphatic diacids include butanediic acid, adipic acid, azelaic acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, and dimerized fatty acids. These dimerized fatty acids preferably have a dimer content of at least 98%. They are preferably hydrogenated. Examples include products marketed by Croda under the trademark name Pripol, by BASF under the trademark name Empol, by Oleon under the trademark name Radiacid, and polyoxyalkylene α,ω-diacids. Examples of aromatic diacids include terephthalic acid (T) and isophthalic acid (I). Examples of alicyclic diamines include isomers of bis(4-aminocyclohexyl)methane (BACM), bis(3-methyl-4-aminocyclohexyl)methane (BMACM), and 2,2-bis(3-methyl-4-aminocyclohexyl)propane (BMACP), as well as para-aminodicyclohexylmethane (PACM). Other commonly used diamines may be isophoronediamine (IPDA), 2,6-bis(aminomethyl)norbornane (BAMN), and piperazine.

[0058] Examples of a third type of polyamide block include the following: PA6.6 / 6 (6.6 represents the hexamethylenediamine unit condensed with adipic acid, and 6 represents the unit resulting from the condensation of caprolactam), PA6.6 / 6.10 / 11 / 12 (6.6 represents hexamethylenediamine condensed with adipic acid, 6.10 represents hexamethylenediamine condensed with sebaciic acid, 11 represents a unit derived from the condensation of aminoundecanoic acid, and 12 represents a unit derived from the condensation of lauryl lactam).

[0059] The notations PAX / Y and PAX / Y / Z refer to copolyamides, where X, Y, and Z represent the homopolyamide units mentioned above.

[0060] Examples of copolyamides include a copolymer of caprolactam and lauryllactam (PA6 / 12), a copolymer of caprolactam, adipic acid and hexamethylenediamine (PA6 / 66), a copolymer of caprolactam, lauryllactam, adipic acid and hexamethylenediamine (PA6 / 12 / 66), a copolymer of caprolactam and lauryllactam, and a copolymer of 11-aminoundecanoic acid, azelaic acid and hexamethylenediamine (PA Examples include copolymers of caprolactam and lauryl lactam (PA6 / 69 / 11 / 12), copolymers of 11-aminoundecanoic acid, adipic acid, and hexamethylenediamine (PA6 / 66 / 11 / 12), copolymers of lauryl lactam and lauryl lactam, copolymers of azelaic acid and hexamethylenediamine (PA69 / 12), and copolymers of 11-aminoundecanoic acid, terephthalic acid, and decamethylenediamine (PA11 / 10T).

[0061] Advantageously, the polyamide block of copolymer (b) is PA6, PA11, PA12, PA5.4, PA5.9, PA5.10, PA5.12, PA5.13, PA5.14, PA5.16, PA5.18, PA5.36, PA6.4, PA6.9, PA6.10, PA6.12, PA6.13, PA6.14, PA6.16, PA6.18, PA6.36, PA10.4, PA10.9, PA10.10, PA10.1 2. The material comprises a polyamide block selected from PA10.13, PA10.14, PA10.16, PA10.18, PA10.36, PA10.T, PA12.4, PA12.9, PA12.10, PA12.12, PA12.13, PA12.14, PA12.16, PA12.18, PA12.36, PA12.T, PA6 / 12, PA11 / 12, PA11 / 10.10, or mixtures or copolymers thereof. Preferably, the material comprises a block of polyamide PA6, PA11, PA12, PA6.10, PA10.10, PA10.12, PA6 / 12, PA11 / 12, or mixtures or copolymers thereof.

[0062] Polyether blocks of PEBA copolymers are formed from alkylene oxide units. Polyether blocks may, in particular, be PEG (polyethylene glycol) blocks, i.e., blocks formed from ethylene oxide units, and / or PPG (polypropylene glycol) blocks, i.e., blocks formed from propylene oxide units, and / or PO3G (polytrimethylene glycol) blocks, i.e., blocks formed from trimethylene glycol ether units, and / or PTMG (polytetramethylene glycol) blocks, i.e., blocks formed from tetramethylene glycol units, also known as polytetrahydrofuran. The copolymer may contain several types of polyethers in its chain, and the copolyethers may be in block or random form.

[0063] Blocks obtained by oxyethylation of bisphenols, such as bisphenol A, can also be used. The latter product is described in particular in European Patent No. 613919.

[0064] The polyether block may also be formed from an ethoxylated primary amine. An example of an ethoxylated primary amine is given by formula: Examples of products of TIFF0007862370000001.tif46170 (where m and n are integers from 1 to 20, and x is an integer from 8 to 18) can be found. These products are commercially available, for example, from CECA under the trade name Noramox® and from Clariant under the trade name Genamin®.

[0065] The polyether block may include a polyoxyalkylene block having an NH2 chain terminus, such a block can be obtained by cyanoacetylation of an α,ω-dihydroxylated aliphatic polyoxyalkylene block known as a polyetherdiol. More specifically, commercially available Jeffamine or Elastamine can be used (e.g., the commercially available Jeffamine® D400, D2000, ED 2003, XTJ 542 from Huntsman, and also described in the literature Japanese Patent Publication No. 2004-346274, Japanese Patent Publication No. 2004-352794 and European Patent No. 1482011).

[0066] The polyetherdiol block is used in an unmodified form and is co-condensed with a polyamide block having a carboxylic acid-terminated group, or it is aminated to a polyetherdiamine and then condensed with a polyamide block having a carboxylic acid-terminated group.

[0067] While the PEBA copolymer described above comprises at least one polyamide block and at least one polyether block, the present invention also encompasses copolymers comprising three, four (or more) different blocks selected from, for example, those described herein. For example, polyester blocks, polysiloxane blocks, e.g., polydimethylsiloxane (PDMS) blocks, polyolefin blocks, polycarbonate blocks, and mixtures thereof. For example, a copolymer according to the present invention may be a segmented block copolymer (or "triblock" copolymer) comprising three different types of blocks resulting from the condensation of several of the blocks described above. The triblock may be, for example, a copolymer comprising a polyamide block, a polyester block and a polyether block, or a copolymer comprising a polyamide block and two different polyether blocks, e.g., a PEG block and a PTMG block.

[0068] PEBA is formed by the polycondensation of a polyamide block having reactive ends and a polyether block having reactive ends, particularly, 1) A polyamide block having a diamine chain terminus and a polyoxyalkylene block having a dicarboxyl chain terminus, 2) For example, a polyamide block having a dicarboxyl chain end and a polyoxyalkylene block having a diamine chain end, obtained by cyanoethylation and hydrogenation of an α,ω-dihydroxylated aliphatic polyoxyalkylene block known as a polyetherdiol, 3) A polyamide block having a dicarboxyl chain terminus having a polyetherdiol, which in this particular case is a polyether ester amide, It arises from polycondensation.

[0069] Polyamide blocks having dicarboxyl chain ends are derived, for example, from the condensation of polyamide precursors in the presence of chain-restricted dicarboxylic acids. Polyamide blocks having diamine chain ends are derived, for example, from the condensation of polyamide precursors in the presence of chain-restricted diamines.

[0070] Particularly preferred PEBA copolymers in the context of the present invention are copolymers comprising blocks from among PA11 and PEG, PA11 and PTMG, PA12 and PEG, PA12 and PTMG, PA6.10 and PEG, PA6.10 and PTMG, PA6 and PEG, PA6 and PTMG, PA6 / 12 and PTMG, PA6 / 12 and PEG, PA11 / 12 and PTMG, and PA11 / 12 and PEG.

[0071] The PEBA copolymer according to the present invention is a branched copolymer having a number-average functional value (Efn) greater than 2, preferably 3 or more.

[0072] Preferably, branching is carried out by a compound containing at least three functional groups that can react with the carboxylic acid chain ends of the PEBA copolymer, thus enabling the formation of a branched PEBA copolymer.

[0073] According to the first modified form, branching is carried out by polyol residues that link polyamide blocks of the PEBA copolymer, wherein the polyol is a polyol containing at least three hydroxyl groups.

[0074] According to this modified form, branched PEBA can be prepared, for example, by adding one or more polyols containing at least three hydroxyl groups during synthesis.

[0075] Branched PEBA can be prepared according to a two-step preparation process (including a first step of synthesizing a polyamide block, followed by a second step of condensation of the polyamide and polyether blocks) or by a one-step preparation process. The polyol is added together with the polyamide block precursor.

[0076] A common two-step method for preparing PEBA copolymers having an ester bond between a PA block and a PE block is known, for example, as described in French Patent No. 2846332. A common method for preparing PEBA copolymers having an amide bond between a PA block and a PE block is known, for example, as described in European Patent No. 1482011. A polymer containing a polyamide block and a polyether block having randomly distributed units can also be prepared by mixing a polyether block with a polyamide precursor and a dioxy chain restrictor (one-step process). Regardless of the method used (two-step or one-step), the polyol is added together with the polyamide precursor.

[0077] Preferably, the branched PEBA of the present invention is prepared according to a two-step preparation process.

[0078] The addition of a polyol having a functional value greater than 2 preferably creates crosslinking bonds that connect the polyamide blocks of the copolymer to each other, via ester bonds.

[0079] Polyols containing at least three hydroxyl groups are particularly, • Monomeric polyols, especially monomeric aliphatic triols such as glycerol, trimethylolpropane, and pentaerythritol, and / or This is understood to mean polymeric polyols, particularly triols containing polyether chains, polycaprolactone triols, and mixed polyether-polyester polyols containing at least three hydroxyl groups.

[0080] Advantageously, the polyol is selected from pentaerythritol, trimethylolpropane, trimethylolethane, hexanetriol, diglycerol, methyl glucoside, tetraethanol, sorbitol, dipentaerythritol, cyclodextrin, polyether polyols containing at least three hydroxyl groups, and mixtures thereof.

[0081] The weight-average molecular weight of the polyol is preferably 3000 g / mol or less, more preferably 2000 g / mol or less. Generally, it is in the range of 50 to 1000 g / mol, preferably 50 to 500 g / mol, and preferably 50 to 200 g / mol.

[0082] Advantageously, the polyol is added in an amount ranging from 0.01% to 10% by weight, preferably 0.01% to 5% by weight, and more preferably 0.05% to 0.5% by weight, relative to the total weight of the polyol, the polyamide block precursor, and the polyether block. Alternatively, the polyol may be added in an amount of 3.5 to 35 μeq / g relative to the total weight of the polyol, the polyamide block precursor, and the polyether block.

[0083] According to the second modified form, branching of copolymer (b) is carried out by polyepoxide compound residues that bond polyamide blocks of copolymer (b), and the polyepoxide compound is a polyepoxide compound containing at least three epoxide functional groups.

[0084] According to this modification, branched PEBA is in a molten state. PEBA copolymers and epoxide compounds It can be prepared by a manufacturing method that includes a step of mixing the following.

[0085] The epoxide equivalent weight (EEW) of polyepoxide compounds is typically 80 to 2800 g / mol, preferably 90 to 700 g / mol.

[0086] According to one embodiment, the epoxide compound is selected from triglycidyl isocyanurate, trimethylolpropane triglycidyl ether, epoxy novolac resin, and epoxidized oil.

[0087] According to one embodiment, the epoxide compound is selected from a random copolymer of epoxy-functionalized (meth)acrylates obtained by copolymerizing at least one (meth)acrylic monomer having an epoxy functional group with at least one monomer selected from alkene monomers, vinyl acetate monomers, non-functionalized (meth)acrylic monomers, styrene monomers, or a mixture of one or more of these entities.

[0088] For the purposes of the present invention, the term (meth)acrylic monomer includes both acrylic monomers and methacrylic monomers. Examples of (meth)acrylic monomers having epoxy functional groups include both acrylates and methacrylates. Examples of these epoxy functional group-containing (meth)acrylic monomers include, but are not limited to, 1,2-epoxy group-containing monomers such as glycidyl acrylate and glycidyl methacrylate. Other suitable monomers may be allyl glycidyl ether, glycidyl ethyl acrylate, and glycidyl itaconate.

[0089] Suitable alkene monomers may be, but are not limited to, ethylene, propylene, butylene, and mixtures thereof.

[0090] Suitable acrylate monomers and methacrylate monomers include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, sec-butyl acrylate, isobutyl acrylate, t-butyl acrylate, n-amyl acrylate, isoamyl acrylate, isobornyl acrylate, n-hexyl acrylate, 2-ethylbutyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-decyl acrylate, methylcyclohexyl acrylate, cyclopentyl acrylate, and cyclohexyl acrylate. The methacrylate may be, but is not limited to, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, isoamyl methacrylate, butyl methacrylate, 2-ethylbutyl methacrylate, methylcyclohexyl methacrylate, cinnamyl methacrylate, clotyl methacrylate, cyclohexyl methacrylate, cyclopentyl methacrylate, 2-ethoxyethyl methacrylate, and isobornyl methacrylate.

[0091] Examples of styrene monomers include, but are not limited to, styrene, α-methylstyrene, vinyltoluene, p-methylstyrene, t-butylstyrene, o-chlorostyrene, vinylpyridine, and mixtures thereof. In certain embodiments, the styrene monomers used in the present invention are styrene and alpha-methylstyrene.

[0092] According to one embodiment, the epoxide compound is selected from random styrene-(meth)acrylate copolymers having epoxy functional groups, obtained from at least one (meth)acrylic monomer having an epoxy functional group and at least one non-functional (meth)acrylic monomer and / or a styrene monomer.

[0093] In one embodiment, the epoxide compound contains at least one (meth)acrylic monomer having 25% to 50% by weight of epoxy functional groups, and at least one non-functional (meth)acrylic monomer and / or styrene monomer in 75% to 50% by weight. More preferably, the epoxide compound contains at least one (meth)acrylic monomer having 25% to 50% by weight of epoxy functional groups, at least one styrene monomer in 15% to 30% by weight, and at least one non-functional acrylate monomer and / or methacrylate monomer in 20% to 60% by weight.

[0094] In one embodiment, the epoxide compound contains, based on the total weight of monomers, at least one (meth)acrylic monomer having epoxy functional groups in an amount of 50% to 80% by weight, and at least one non-functional (meth)acrylic monomer and / or styrene monomer in an amount of 20% to 50% by weight. More preferably, the epoxide compound contains at least one (meth)acrylic monomer having epoxy functional groups in an amount of 50% to 80% by weight, at least one styrene monomer in an amount of 15% to 45% by weight, and at least one non-functional acrylate monomer and / or methacrylate monomer in an amount of 0% to 5% by weight.

[0095] In one embodiment, the epoxide compound contains at least one (meth)acrylic monomer having epoxy functional groups in a weight of 5% to 25%, and at least one non-functional (meth)acrylic monomer and / or styrene monomer in a weight of 75% to 95%. More preferably, the epoxide compound contains at least one (meth)acrylic monomer having epoxy functional groups in a weight of 5% to 25%, at least one styrene monomer in a weight of 50% to 95%, and at least one non-functional acrylate monomer and / or methacrylate monomer in a weight of 0% to 25%.

[0096] According to the embodiment, the epoxide compound is selected from styrene-(meth)acrylate copolymers having epoxy functional groups obtained from at least one (meth)acrylic monomer having epoxy functional groups and at least one non-functional (meth)acrylic monomer and / or styrene monomer monomer, and is preferably selected from styrene-(meth)acrylate copolymers having epoxy functional groups obtained from at least one (meth)acrylic monomer having epoxy functional groups and at least one styrene monomer monomer.

[0097] According to one embodiment, the epoxide compound is obtained from at least one (meth)acrylic monomer having epoxy functional groups and at least one styrene monomer. According to one embodiment, the epoxide compound contains, by weight, at least one (meth)acrylic monomer having epoxy functional groups at 50% to 80% and at least one styrene monomer at 20% to 50% of the total weight of the monomers.

[0098] According to one preferred embodiment, the epoxide compound is a random copolymer of styrene and glycidyl methacrylate.

[0099] The weight-average molecular weight (Mw) of the styrene-(meth)acrylate copolymer having epoxy functional groups is preferably less than 25,000 g / mol, more preferably less than 20,000 g / mol. Generally, it is in the range of 3,000 to 15,000 g / mol, preferably 5,000 to 10,000 g / mol.

[0100] According to one embodiment, the amount of polyepoxide compound used in this process is 0.01% to 5% by weight, preferably 0.01% to 2% by weight, and more preferably 0.05% to 1% by weight, relative to the total weight of the PEBA copolymer.

[0101] According to one preferred embodiment, the amount of polyepoxide compound used in the process is less than 1% by weight, typically 0.15% to 0.95%, preferably 0.3% to 0.9%, or 0.35% to 0.85%, relative to the total weight of the PEBA copolymer.

[0102] According to one embodiment, the molar ratio of the carboxylic acid chain end content of the PEBA copolymer to the epoxide functional group content of the polyepoxide compound is typically 2 to 20, preferably 3 to 10.

[0103] Advantageously, the process is typically carried out by reactive extrusion in an extruder.

[0104] In the present invention, the branched PEBA copolymer has a weight-average molecular weight Mw greater than 80,000 g / mol. Preferably, the weight-average molecular weight of the branched PEBA copolymer is in the range of 80,000 to 300,000 g / mol, more preferably 90,000 to 250,000 g / mol, and even more preferably 100,000 to 200,000 g / mol.

[0105] The weight-average molecular weight is expressed as PMMA equivalent (used as a calibration standard) and can be measured by size exclusion chromatography according to standard ISO 16014-1:2012. The copolymer is dissolved in hexafluoroisopropanol stabilized with 0.05 M potassium trifluoroacetate at a concentration of 1 g / l to 2 g / l for 24 hours at room temperature, then passed through a column at a flow rate of, for example, 1 ml / min, and the molar mass is measured by a differential refractometer. Size exclusion chromatography can be performed using a modified silica column, for example, on a set of modified silica including a 1000 Å column with dimensions of 300 × 8 mm and a particle size of 7 μm, a 100 Å column with dimensions of 300 × 8 mm and a particle size of 7 μm, and a pre-column with dimensions of 50 × 8 mm (e.g., PGF column and pre-column from Polymer Standards Service), at a temperature of, for example, 40°C.

[0106] In certain embodiments, the branched PEBA copolymer has a weight-average molecular weight Mw in the range of 80,000 to 90,000 g / mol, or 90,000 to 100,000 g / mol, or 100,000 g / mol to 125,000 g / mol, or 125,000 to 150,000 g / mol, or 150,000 to 175,000 g / mol, or 175,000 to 200,000 g / mol, or 200,000 to 225,000 g / mol, or 225,000 to 250,000 g / mol, or 250,000 to 275,000 g / mol, or 275,000 to 300,000 g / mol.

[0107] The branched PEBA copolymer can have a number-average molar mass Mn in the range of 30,000 to 100,000 g / mol, preferably 35,000 to 80,000 g / mol, and more preferably 40,000 to 70,000 g / mol.

[0108] The number-average molar mass is expressed as PMMA equivalent and can be measured according to the method described above and in accordance with standard ISO 16014-1. In certain embodiments, branched copolymers containing rigid and flexible blocks have a number-average molar mass Mn in the range of 30,000 to 35,000 g / mol, or 35,000 to 40,000 g / mol, or 40,000 to 45,000 g / mol, or 45,000 to 50,000 g / mol, or 50,000 to 55,000 g / mol, or 55,000 to 60,000 g / mol, or 60,000 to 70,000 g / mol, or 70,000 to 80,000 g / mol, or 80,000 to 90,000 g / mol, or 90,000 to 100,000 g / mol.

[0109] Branched PEBA copolymers can have a z-average molar mass Mz in the range of 200,000 to 1,000,000 g / mol. The z-average molar mass is expressed as PMMA equivalent and can be measured according to the method described above in accordance with standard ISO 16014-1. In certain embodiments, branched copolymers containing rigid and flexible blocks have a z-average molar mass Mz of 200,000 to 250,000 g / mol, or 250,000 to 300,000 g / mol, or 300,000 to 350,000 g / mol, or 350,000 to 400,000 g / mol, or 400,000 to 450,000 g / mol, or 450,000 to 500,000 g / mol, 5000 The copolymer has a z-average molar mass Mz in the ranges of 0-550,000 g / mol, 550,000-600,000 g / mol, 600,000-650,000 g / mol, 650,000-700,000 g / mol, 700,000-750,000 g / mol, 750,000-800,000 g / mol, 850,000-900,000 g / mol, and 950,000-1,000,000 g / mol. The polydispersity of the copolymer can be defined by the ratio of the weight-average molecular weight Mw of the copolymer to the number-average molar mass Mn of the copolymer (Mw / Mn molar ratio) and / or the ratio of the z-average molar mass Mz of the copolymer to the weight-average molecular weight Mw of the copolymer (Mz / Mw molar ratio).

[0110] The branched PEBA copolymer has a Mw / Mn molar mass ratio of 2.2 or higher, preferably 2.4 or higher. In certain embodiments, the copolymer has a Mw / Mn molar mass ratio of 2.3 or higher, or 2.4 or higher, or 2.5 or higher, or 2.6 or higher, or 2.7 or higher, or 2.8 or higher, or 2.9 or higher, or 3 or higher.

[0111] The branched PEBA copolymer may have an Mz / Mw molar mass ratio of 1.8 or higher, preferably 2.0 or higher, preferably 2.5 or higher, or 2.7 or higher, or 2.9 or higher, or 3.1 or higher, or 3.3 or higher, or 3.5 or higher.

[0112] Polyolefin (c) The composition may include a polyolefin (c) selected from functionalized polyolefins (c1), unfunctionalized polyolefins (c2), and mixtures thereof.

[0113] Polyolefins typically have a flexural modulus of less than 100 MPa and a Tg of less than 0°C (measured according to standard 11357-2 at the inflection point of a DSC thermogram), as measured according to standard ISO 178.

[0114] Non-functionalized polyolefins (C2) are conventionally homopolymers or copolymers of alpha-olefins or diolefins, such as ethylene, propylene, 1-butene, 1-octene, or butadiene. Examples include the following: Polyethylene homopolymers and copolymers, particularly LDPE, HDPE, LLDPE (linear low-density polyethylene), VLDPE (very low-density polyethylene), and metallocene polyethylene. • Propylene homopolymer or copolymer, • Ethylene / α-olefin copolymers, such as ethylene / propylene, EPR (an abbreviation for ethylene-propylene rubber), and ethylene / propylene / diene (EPDM).

[0115] Functionalized polyolefins (c1) can be polymers of alpha-olefins having reactive units. Such reactive units are acid, anhydride, or epoxide functional groups. Examples include the aforementioned polyolefins (C2) grafted, copolymerized, or tern-copolymerized with unsaturated epoxides such as glycidyl (meth)acrylate, or carboxylic acids such as (meth)acrylic acid (the latter of which can be completely or partially neutralized with a metal such as Zn), or their corresponding salts or esters, or carboxylic acid anhydrides such as maleic anhydride. Functionalized polyolefins are, for example, PE / EPR mixtures, the weight ratio of which can vary over a wide range, for example between 40 / 60 and 90 / 10, and the mixture is co-grafted with anhydrides, particularly maleic anhydride, for example between 0.01% and 5%, depending on the degree of grafting.

[0116] The functionalized polyolefin (c1) can be selected from the following (co)polymers grafted with maleic anhydride or glycidyl methacrylate, with a degree of grafting of, for example, 0.01% to 5% by weight. • Copolymers of PE, PP, ethylene and propylene, butene, hexene or octene, for example, copolymers containing 35% to 80% ethylene by weight. • Ethylene / alpha-olefin copolymers such as ethylene / propylene, EPR (abbreviation for ethylene-propylene rubber), and ethylene / propylene / diene (EPDM), • A copolymer of ethylene and vinyl acetate (EVA) containing up to 40% vinyl acetate by weight, • A copolymer of ethylene and alkyl (meth)acrylate containing up to 40% by weight of alkyl (meth)acrylate, A copolymer of ethylene, vinyl acetate (EVA), and alkyl (meth)acrylate, containing up to 40% by weight of comonomers.

[0117] The functionalized polyolefin (c1) may also be selected from ethylene / propylene copolymers (products described in European Patent Application Publication No. 0342066) which are predominant in propylene, grafted with maleic anhydride, and then condensed with monoaminated polyamide (or polyamide oligomer).

[0118] The functionalized polyolefin (c1) may be a copolymer or ternary copolymer of at least the following units: (1) ethylene, (2) alkyl (meth)acrylate or saturated vinyl carboxylate, and (3) anhydrides such as maleic anhydride or (meth)acrylic anhydride, or epoxides such as glycidyl (meth)acrylate.

[0119] Examples of the latter type of functionalized polyolefin include the following copolymers, where ethylene preferably accounts for at least 60% by weight, and ter monomers (functional groups) account for, for example, 0.1% to 10% by weight of the copolymer. • Ethylene / alkyl (meth)acrylate / (meth)acrylic acid or maleic anhydride or glycidyl methacrylate copolymer, • Ethylene / vinyl acetate / maleic anhydride or glycidyl methacrylate copolymer, Ethylene / vinyl acetate or alkyl (meth)acrylate / (meth)acrylic acid or maleic anhydride or glycidyl methacrylate copolymer.

[0120] In the copolymer described above, (meth)acrylic acid can be chlorided with Zn or Li.

[0121] The term "alkyl (meth)acrylate" in (c1) or (c2) refers to C1-C8 alkyl methacrylate and acrylate, and can be selected from methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, methyl methacrylate and ethyl methacrylate.

[0122] The copolymers (c1) and (c2) described above can be copolymerized in a random or block manner and may exhibit linear or branched structures.

[0123] Non-functionalized polyolefins (c2) are advantageously selected from polypropylene homopolymers or copolymers, as well as any ethylene homopolymers or copolymers of ethylene and higher α-olefin type comonomers such as butene, hexene, octene, or 4-methyl-1-pentene. Examples include PP, high-density PE, medium-density PE, linear low-density PE, low-density PE, or ultra-low-density PE. Those skilled in the art know that these polyethylenes are produced by "radical" methods, "Ziegler" type catalytic reactions, or more recently, "metallocene" catalytic reactions.

[0124] Functionalized polyolefins (c1) are advantageously selected from any polymer comprising α-olefin units and units having reactive polar functional groups such as epoxides, carboxylic acids, or carboxylic acid anhydrides. Examples of such polymers include terpolymers of ethylene, alkyl acrylates, and maleic anhydride or glycidyl methacrylate, such as Lotader® products, or polyolefins grafted with maleic anhydride, such as Orevac® products, as well as terpolymers of ethylene, alkyl acrylates, and (meth)acrylic acid. Homopolymers or copolymers of polypropylene grafted with carboxylic acid anhydrides and then condensed with monoaminated polyamides or polyamide oligomers may also be included.

[0125] It was observed that the functionalized polyolefin (c1) could improve the compatibility between copolymer (a) and copolymer (b).

[0126] According to one embodiment, the composition contains 0.1% to 50%, preferably 0.1% to 40%, or 0.1% to 30%, or 0.1% to 20% by weight of the above polyolefin (c) based on the total weight of the composition.

[0127] Thermoplastic elastic polymer (d) According to one embodiment, the composition comprises a thermoplastic elastic polymer (d) selected from copolymers containing polyester blocks and polyether blocks, linear PEBA, polyurethane, olefin-based thermoplastic elastomer or olefin-based block copolymer, styrene-diene block copolymer, and / or mixtures thereof, in an amount of 0.1% to 50%, preferably 0.1% to 40%, or 0.1% to 30%, or 0.1% to 20% by weight, based on the total weight of the composition.

[0128] Copolymers containing polyester blocks and polyether blocks typically consist of a flexible polyether block derived from a polyetherdiol and a rigid polyester block resulting from the reaction of at least one dicarboxylic acid with at least one chain-extended short diol unit. The polyester block and polyether block are linked via ester bonds resulting from the reaction of the acidic functional group of the dicarboxylic acid with the hydroxyl functional group of the polyetherdiol. The arrangement of polyether and diacid forms a flexible block, while the arrangement of glycol or butanediol and diacid forms a rigid block of the copolyether ester. The chain-extended short diol can be selected from the group consisting of neopentyl glycol, cyclohexanedimethanol, and aliphatic glycols of the formula HO(CH2)nOH (wherein n is an integer in the range of 2 to 10).

[0129] Advantageously, the diacid is an aromatic dicarboxylic acid containing 8 to 14 carbon atoms. Up to 50 mol% of the aromatic dicarboxylic acid may be replaced with at least one other aromatic dicarboxylic acid containing 8 to 14 carbon atoms, and / or up to 20 mol% may be replaced with an aliphatic dicarboxylic acid containing 2 to 14 carbon atoms.

[0130] Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, dibenzoic acid, naphthalenedicarboxylic acid, 4,4'-diphenylenedicarboxylic acid, bis(p-carboxyphenyl)methaneic acid, ethylenebis-p-benzoic acid, 1,4-tetramethylenebis(p-oxybenzoic acid), ethylenebis(p-oxybenzoic acid), and 1,3-trimethylenebis(p-oxybenzoic acid).

[0131] Examples of glycols include ethylene glycol, 1,3-trimethylene glycol, 1,4-tetramethylene glycol, 1,6-hexamethylene glycol, 1,3-propylene glycol, 1,8-octamethylene glycol, 1,10-decamethylene glycol, and 1,4-cyclohexylene dimethanol. Copolymers containing polyester blocks and polyether blocks are, for example, polyether diols such as polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene glycol (PO3G) or polytetramethylene glycol (PTMG), dicarboxylic acid units such as terephthalic acid and glycol (ethanediol), or copolymers containing polyether units derived from 1,4-butanediol units. Such copolyether esters are described in European Patent No. 402883 and European Patent No. 405227. These polyether esters are thermoplastic elastomers. They may contain plasticizers.

[0132] The composition may include linear PEBA. The number average molar mass Mn of the polyamide blocks in the linear copolymer is preferably 400 to 13000 g / mol, more preferably 500 to 10000 g / mol, even more preferably 600 to 9000 g / mol or 600 to 6000 g / mol. The number average molar mass of the polyether block is preferably 100 to 3000 g / mol, preferably 200 to 2000 g / mol.

[0133] The number average molar mass is set by the content of the chain limiter. This can be calculated according to the following relationship. M n =n monomer xMW repeating unit / n chain limiter +MW chain limiter

[0134] In this formula, n monomer is the number of moles of monomer, n chain limiter is the excess number of moles of chain limiter, MW repeating unit is the molar mass of the repeating unit, MW chain limiterThis is the excess molar mass of the chain limiting agent.

[0135] The number-average molar mass of polyamide and polyether blocks can be measured before copolymerization of the blocks by gel permeation chromatography (GPC) in tetrahydrofuran according to standard ISO 16014-1:2012.

[0136] Advantageously, the mass ratio of the polyamide block to the polyether block of the copolymer is 0.1 to 20, preferably 0.3 to 5, and more preferably 0.3 to 2.

[0137] Thermoplastic polyurethanes are linear or slightly branched polymers consisting of rigid blocks and flexible elastomer blocks. They can be produced by reacting flexible elastomer polyethers or polyesters having hydroxyl-terminated groups with diisocyanates such as methylene diisocyanate or toluene diisocyanate. These polymers can be chain-extended with glycols, diamines, diacides, or amino alcohols. The reaction products of isocyanates and alcohols are urethanes, and these blocks are relatively rigid and have high melting points. These rigid blocks with high melting points are responsible for the thermoplasticity of polyurethanes.

[0138] Olefin-based thermoplastic elastomers contain repeating units of ethylene and higher primary olefins, such as propylene, hexene, octene, or a combination of two or more of these, and optionally 1,4-hexadiene, ethylidene norbornene, norbornadiene, or a combination of two or more of these. Olefin-based elastomers may be functionalized by grafting with acid anhydrides such as maleic anhydride.

[0139] Styrene-diene block copolymers contain repeating units derived from polystyrene units and polydiene units. Polydiene units are derived from polybutadiene, polyisoprene units, or copolymers of these two. The copolymers may be hydrogenated to produce saturated rubber skeleton segments commonly known as styrene / butadiene / styrene (SBS) or styrene / isoprene / styrene (SIS) thermoplastic elastomers or styrene / ethylene-butene / styrene (SEBS) or styrene / ethylene-propylene / styrene (SEPS) block copolymers. They may also be functionalized by grafting with acid anhydrides such as maleic anhydride.

[0140] Crosslinking agent The composition contains 0.01% to 2%, preferably 0.05% to 2%, or 0.05% to 1.8% by weight of a crosslinking agent based on the total weight of the composition. Generally, the crosslinking agent is selected from agents that enable crosslinking of EVA, which may include one or more organic peroxides, such as dialkyl peroxides, peroxyesters, peroxydicarbonates, peroxyketals, diacylperacids, or combinations of two or more of these. Examples of peroxides include dicumyl peroxide, di(3,3,5-trimethylhexanoyl) peroxide, t-butyl peroxypivalate, t-butyl peroxyneodecanoate, di(sec-butyl) peroxydicarbonate, t-amyl peroxyneodecanoate, 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 1,3-bis(tert-butylperoxyisopropyl)benzene, or any combination of two or more of these. These peroxides are available from Arkema under the trade name Luperox®.

[0141] foaming agent The composition may contain 0.5% to 10%, preferably 0.5% to 8%, of the total weight of the composition as a blowing agent. The blowing agent (also known as a leavening agent) may be a chemical or physical agent. It is preferably a chemical agent such as azodicarbonamide, dinitrosopentamethylenetetramine, p-toluenesulfonyl hydrazide, p,p'-oxybis(benzenesulfonyl hydrazide), or a combination of two or more of these, or a mixture based on citric acid and sodium bicarbonate (NaHCO3) (e.g., products in the Hydrocerol® range of Clariant). It may also be a physical agent, such as dinitrogen or carbon dioxide, or a hydrocarbon, chlorofluorocarbon, hydrochlorocarbon, hydrofluorocarbon or hydrochlorofluorocarbon (saturated or unsaturated). For example, butane or pentane can be used. To adapt the expansion decomposition temperature and the foaming process, the blowing agent may be a (physical and / or chemical) blowing agent or a mixture of a blowing agent and an activator.

[0142] According to one embodiment, when a chemical blowing agent is used, the foam further contains 0.1% to 10%, or preferably 0.1% to 5%, of the activator of the blowing agent. The activator may be one or more metal oxides, metal salts, or organometallic complexes, or a combination of two or more thereof. Examples include ZnO, zinc stearate, MgO, or a combination of two or more thereof.

[0143] additives The composition may contain additives in an amount of 0.1% to 20%, preferably 0.1% to 15%, or 0.1% to 12%, or 0.1% to 10%, by weight, relative to the total weight of the composition.

[0144] Additives are typically conventional additives used in foams that contribute to improving the properties of the foam and / or the foaming process.

[0145] Typically, additives may include pigments (TiO2 and other compatible coloring pigments), dyes, adhesion promoters (to improve the adhesion of the expanded foam to other materials), organic or inorganic fillers (e.g., calcium carbonate, barium sulfate and / or silicon dioxide), reinforcing agents, plasticizers, nucleating agents (in pure or concentrated form, e.g., CaCO3, ZnO, SiO2, or combinations of two or more thereof), rubber (to improve rubber elasticity, such as natural rubber, SBR, polybutadiene and / or ethylene propylene ternary copolymers), stabilizers, antioxidants, UV absorbers, flame retardants, carbon black, carbon nanotubes, mold release agents, impact resistant agents, and additives to improve processability (processing aids), e.g., stearic acid). Antioxidants (Tarrytown, New York) may include phenolic antioxidants, such as IRGANOX from Ciba Geigy Inc.

[0146] process The foam of the present invention can be obtained from the composition defined above by several processes, such as compression molding, injection molding, or a hybrid of extrusion molding and molding.

[0147] The present invention also provides a method for preparing a foam, (i) • Copolymer (a), • Copolymer (b), • A crosslinking agent, preferably a peroxide, • A foaming agent, preferably a chemical foaming agent, Depending on the circumstances, a polyolefin (c), a thermoplastic elastic polymer (d), and at least one additive, A step of providing a mixture containing, (ii) A step of molding the mixture by injection molding, compression / molding or extrusion, (iii) A step of foaming the mixture, This includes methods.

[0148] The above steps can be performed separately or simultaneously.

[0149] According to one embodiment, steps (i)+(ii), (ii)+(iii), or (i)+(ii)+(iii) are performed simultaneously.

[0150] The preparation process can be carried out using the same equipment, such as a mixer or an extruder.

[0151] According to one embodiment, step (i) is: The total weight equals 100% of the mixture. • Copolymer (a) of 30% to 99.9% by weight, • 0.1% to 50%, preferably 0.1% to 40% by weight of copolymer (b), • 0% to 50% by weight of polyolefin (c) and / or thermoplastic elastic polymer (d), • At least one additive in an amount of 0.1% to 20% by weight. • 0.01% to 2% by weight of a crosslinking agent, preferably a peroxide. • 0.5% to 10% by weight of a blowing agent, preferably a chemical blowing agent. This is done by mixing the materials in a molten state.

[0152] According to another variant, the blowing agent is introduced during and / or after step (ii). The amount of blowing agent introduced into the method is typically 0.5% to 10% by weight relative to the total weight of the mixture.

[0153] A uniform molten mixture is obtained at the end of the mixing process.

[0154] The compounds can be mixed using any means known to those skilled in the art, such as a Banbury mixer, an intensive mixer, a roll mixer, an open mill, or an extruder.

[0155] Time, temperature, and shear rate can be adjusted to ensure optimal dispersion without premature crosslinking or foaming. High mixing temperatures can lead to premature crosslinking and foaming as a result of the decomposition of crosslinking agents, such as peroxides and foaming agents. Compounds can form a homogeneous mixture when they are mixed at temperatures of approximately 60°C to 200°C, or 80°C to 180°C, or 70°C to 150°C, or 80°C to 130°C. The upper temperature limit for good operation may depend on the initial decomposition temperatures of the crosslinking and foaming agents used.

[0156] The (co)polymer may be mixed in a molten state before being mixed with other compounds. For example, the polymer may be mixed in a molten state in an extruder at a temperature in the range of about 250°C to allow for good potential mixing. The resulting mixture can then be mixed with the other compounds mentioned above.

[0157] After mixing, the mixture can be molded by injection molding, compression, or extrusion within a mold.

[0158] The mixture may be molded into sheets, pellets, or granules having dimensions suitable for foaming. Roll mixers are frequently used to produce sheets. Extruders can be used to mold the composition into pellets or granules.

[0159] The foaming process can be carried out in a compression mold at a temperature and time that allows for the decomposition of the crosslinking agent and the foaming agent. The foaming process can be carried out while the composition is being injected into the mold and / or by opening the mold. The temperature and time applied during the foaming process can be easily adjusted by those skilled in the art to optimize the foaming of EVA and / or copolymers of ethylene and alkyl (meth)acrylate. Alternatively, the foaming process can be carried out directly when the product comes out of the extrusion molding process. The resulting foam may be further molded to the dimensions of the final product by any means known in the art, such as thermoforming and compression molding.

[0160] Although the PEBA copolymer does not contribute to the crosslinking of the foam under these conditions, it was unexpectedly observed that its presence does not hinder the formation of crosslinked foams of EVA and / or copolymers of ethylene and alkyl (meth)acrylate, and further provides the foam with particularly interesting properties as described above.

[0161] Foams and their use The foam according to the present invention preferably has a density of 800 kg / m³. 3 Below, 600 kg / m² is given higher priority. 3 Below, with even higher priority, is 400 kg / m 3 The following or 300 kg / m 3 The following is particularly preferable: 200 kg / m 3 It has the following densities, for example, 25-800 kg / m³. 3 More specifically, preferably 50-600 kg / m 3 , or 50-200 kg / m 3 It can have a density of [value missing]. The density can be controlled by adapting the parameters of the manufacturing process.

[0162] Preferably, this foam has a rebound elasticity of 50% or more, preferably 55% or more, according to the ISO 8307:2007 standard. Generally, the elasticity of the foam of the present invention is less than 80%, or 75%, or 70%.

[0163] Preferably, the foam has a compressive strain of 60% or less, preferably 55% or less, or 50% or less after 30 minutes according to the standard ISO 7214:2012.

[0164] Furthermore, it is preferable that this foam also exhibits excellent fatigue strength and moisture resistance.

[0165] The foam of the present invention possesses improved elasticity while still retaining moderate rigidity and lightness, good dimensional stability and good abrasion resistance, making it particularly suitable for application in footwear.

[0166] The foam of the present invention provides better adhesion to other elements to facilitate complex assembly. This is because EVA foam is a base material that is not very polar and adheres poorly to other elements of a shoe, complicating the assembly process. This is of particular interest in the context of shoes, which are often multi-layered.

[0167] The foam according to the present invention can be used to manufacture sports articles such as sports shoe soles, ski boots, midsoles, insoles, or other functional sole components, in the form of inserts for various parts of the sole (e.g., heel or arch), or in the form of reinforcing or inserting other upper components into the structure of the upper, or in the form of protection.

[0168] It may be used to manufacture balls, sports gloves (e.g., football gloves), golf ball components, rackets, and protective elements (jackets, helmet internal elements, shells, etc.).

[0169] Typically, these articles can be manufactured by injection molding or injection molding followed by compression molding.

[0170] The foam according to the present invention possesses advantageous impact resistance, vibration resistance, and noise resistance, combined with tactile properties suitable for equipment products. Therefore, it can be used to manufacture railway rail pads or various components in the automotive, transportation, electrical and electronic equipment, construction, or manufacturing industries. [Examples]

[0171] The examples were carried out using the mixtures listed in Table 1.

[0172] The EVA copolymer used is a product sold by SK Functional Polymer: Evatane® 28-05, and is an EVA copolymer with a vinyl acetate content of 28% by weight and a melt flow index of 5 g / 10 min.

[0173] The branched copolymers of Example 1 and Comparative Example 2 contain a PA6 / 12 block with a number-average molar mass of 1000 g / mol and a PTMG block with a number-average molar mass of 1000 g / mol. Branching is carried out by adding a trimethylolpropane-type polyol residue containing three hydroxyl groups at a weight of 0.02% to the total weight of the PEBA copolymer, according to the protocol described in European Patent No. 1783156A1 of the literature. The thus branched copolymer has a weight-average molecular weight Mw of 134000 g / mol, a Mw / Mn molar mass ratio of 2.9, and a Mz / Mw molar mass ratio of 2.2. The compounds were mixed in a mixer at 100°C for 10 minutes to form a molten mass. The mixture was then molded (in sheet form) at 95°C using a roll mixer. The resulting sheet was then foamed by compression / molding in a press (Darragon) at 160°C for 20 minutes.

[0174] The following mechanical tests were performed on the foam: • Density measurement according to ISO 845 standard (kg / m³) 3 ), ·Hardness (Asker C), • Shrinkage rate (%) after 1 hour at 70°C • Ball rebound elasticity (%): Corresponds to the ISO 8307 standard (a 16.8g steel ball with a diameter of 16mm is dropped from a height of 500mm onto a foam sample. Rebound elasticity corresponds to the percentage of energy returned to the ball, or the percentage of the initial height the ball reaches upon rebound). • Compressive strain (comp.set, %): This measurement is performed by compressing the sample to a given degree of deformation for a given time, then releasing the stress, and observing the residual deformation after the recovery time. The measurement conforms to the standard ISO 7214, with a deformation of 50%, a holding time of 6 hours, and a temperature of 50°C. TIFF0007862370000002.tif121170

[0175] The parameter "foaming ability" shown in Table 1 indicates the composition's ability to repeatedly form high-quality foams. It is determined according to the following criteria. o: Good expansion of the foam in three spatial directions, dimensions of the foam preserved after cooling, fine and uniform cell structure, x: Dimensions of foam lost after cooling due to weak (or no) expansion, collapse, and / or a rough, non-uniform cell structure of the foam. TIFF0007862370000003.tif53170

[0176] A cross-linked EVA foam (Example 1) containing 20% ​​by weight of branched PEBA in the polymer matrix was uniformly and stably formed. The test results were reproducible (three foams were produced across three tests). The mechanical performance quality of the foam was evaluated as a 50% vs. 54% increase in rebound elasticity, a decrease in density (210 vs. 181 kg / m³) without any decrease in hardness or compressive strain. 3 ), and the reduction in shrinkage after annealing at 70°C for 1 hour are revealed. Comparative Example 2 shows that a good quality foam cannot be obtained from branched PEBA alone under similar conditions.

Claims

1. - A copolymer (a) selected by weight from ethylene-vinyl acetate (EVA) copolymer, copolymer of ethylene and alkyl (meth)acrylate and / or mixture thereof, comprising 30% to 99.9% by weight, - A branched copolymer (b) containing 0.1% to 40% by weight of polyamide blocks and polyether blocks, and having a number-average functional value (Efn) greater than 2, - A polyolefin (c) and / or thermoplastic elastic polymer (d) in an amount of 0% to 50% by weight relative to the total weight of the composition, - Contains 0.01% to 2% by weight of a crosslinking agent, The total weight equals 100%. composition.

2. - A copolymer (a) selected by weight from ethylene-vinyl acetate (EVA) copolymer, copolymer of ethylene and alkyl (meth)acrylate and / or mixture thereof, comprising 50% to 99.9% by weight, - A branched copolymer (b) containing 0.1% to 30% by weight of polyamide blocks and polyether blocks, and having a number-average functional value (Efn) greater than 2, - A polyolefin (c) and / or thermoplastic elastic polymer (d) in an amount of 0.1% to 40% by weight relative to the total weight of the composition, - Contains 0.01% to 2% by weight of a crosslinking agent, The total weight equals 100%. The composition according to claim 1.

3. The composition according to claim 1 or 2, wherein the branching of copolymer (b) is carried out by polyol residues that bind polyamide blocks of copolymer (b), and the polyol is a polyol containing at least three hydroxyl groups.

4. The composition according to claim 1 or 2, wherein the branching of the copolymer (b) is carried out by polyepoxide compound residues that bond polyamide blocks of copolymer (b), and the polyepoxide compound is a polyepoxide compound comprising at least three epoxide functional groups.

5. The polyamide blocks of copolymer (b) are PA6, PA11, PA12, PA5.4, PA5.9, PA5.10, PA5.12, PA5.13, PA5.14, PA5.16, PA5.18, PA5.36, PA6.4, PA6.9, PA6.10, PA6.12, PA6.13, PA6.14, PA6.16, PA6.18, PA6.36, PA10.4, PA10.9, PA10.10, PA10.12, PA10.13, PA10.14, PA10.16, PA10.18, PA10.36, PA10. The composition according to any one of claims 1 to 4, comprising a polyamide block selected from T, PA12.4, PA12.9, PA12.10, PA12.12, PA12.13, PA12.14, PA12.16, PA12.18, PA12.36, PA12.T, PA6 / 12, PA11 / 12, PA11 / 10.10, or mixtures or copolymers thereof.

6. The composition according to any one of claims 1 to 5, wherein the polyether block of copolymer (b) is selected from a PEG block and / or a PPG block and / or a PO3G (polytrimethylene glycol) block and / or a PTMG block.

7. The composition according to any one of claims 1 to 6, wherein the weight-average molecular weight (Mw) of copolymer (b) exceeds 80,000 g / mol.

8. The composition according to any one of claims 1 to 7, wherein the Mw / Mn molar mass ratio of copolymer (b) is 2.2 or more, and / or the Mz / Mw molar mass ratio of copolymer (b) is 1.8 or more.

9. The composition according to claim 1 or 2, wherein the polyolefin (c) is a functionalized polyolefin (c1).

10. The composition according to claim 1 or 2, wherein the thermoplastic elastic polymer (d) is selected from a copolymer containing a polyester block and a polyether block, a thermoplastic polyurethane, an olefin-based thermoplastic elastomer or an olefin-based block copolymer, a styrene-diene block copolymer, and / or a mixture thereof.

11. A foam of the composition according to any one of claims 1 to 10.

12. (i) • Copolymer (a), • Copolymer (b) and Crosslinking agent and, Depending on the circumstances, a polyolefin (c), a thermoplastic elastic polymer (d), and at least one additive, A step of providing a mixture containing, (ii) A step of molding the mixture by injection molding, compression / molding or extrusion, A method for preparing the composition according to any one of claims 1 to 10, comprising:

13. (i) • Copolymer (a), • Copolymer (b) and Crosslinking agent and, • Foaming agent and, Depending on the circumstances, a polyolefin (c), a thermoplastic elastic polymer (d), and at least one additive, A step of providing a mixture containing, (ii) A step of molding the mixture by injection molding, compression / molding or extrusion, (iii) A step of foaming the mixture, A method for preparing the foam according to claim 11, including the method described in claim 11.

14. Step (i) is performed so that the total weight of the mixture reaches 100%. - Copolymer (a) of 30% to 99.9% by weight, - Copolymer (b) at 0.1% to 50% by weight, - 0% to 50% by weight of polyolefin (c) and / or thermoplastic elastic polymer (d), - At least one additive in an amount of 0% to 20% by weight, - 0.01% to 2% by weight of crosslinking agent, - 0.5% to 10% by weight of foaming agent, The method according to claim 13, which is carried out by mixing the in a molten state.

15. A composition or foam that can be obtained according to the method described in any one of claims 12 to 14.

16. An article comprising at least one element consisting of the composition or foam described in any one of claims 1 to 11 or 15.

17. The article according to claim 16, selected from shoe soles, large or small balls, gloves, personal protective equipment, rail pads, automotive parts, building components, and electrical and electronic equipment components.

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