Compositions based on polyamides and polymers containing polyamide blocks and polyethylene glycol blocks

Abstract

The present invention relates to polyamides, polymers having polyamide (PA) blocks and polyethylene glycol (PEG) blocks, functionalized polyolefins, and compositions comprising polyolefins, wherein the weight ratio of (a+b) / (c+d) is less than 1. The present invention also relates to methods for producing the compositions, kits for obtaining the compositions, articles comprising or made from the compositions, and methods for producing the articles.

Description

[Technical Field]

[0001] The present invention relates to polyamides, polymers having polyamide (PA) blocks and polyethylene glycol (PEG) blocks, functionalized polyolefins, and compositions comprising polyolefins. The invention also relates to methods for producing the compositions, kits for obtaining the compositions, articles comprising or made from the compositions, and methods for producing the articles. [Background technology]

[0002] Non-porous breathable films, or films that are impermeable yet breathable, are widely used in a variety of applications. In one such application, non-porous breathable films are advantageously used in packaging, particularly food packaging, for perishable products such as fruits, vegetables, fresh meat, and fish fillets. The quality and shelf life of these perishable products can be improved by optimizing the environment within the package, particularly by adjusting the moisture vapor transmission rate (MVTR), permeability, and selectivity for gases such as CO and O. MVTR, also known as water vapor transmission rate (WVTR), is the amount of water vapor that passes through a substance or material over a specific period of time. In food packaging and storage, a high MVTR value is undesirable because it can cause the fruit or vegetable to wilt.

[0003] U.S. Pat. No. 5,959,042 discloses a material for obtaining a non-porous breathable film, comprising (a) a polyamide, (b) a polymer having a PA block and a polyether PEG block, (c) optionally a polyolefin, and (d) a functionalized polyolefin, wherein the amounts by weight of a, b, c, and d are such that a>0, b>0, c+d>0, a+b+c+d=100, a / b>0.2, (a+b) / (c+d)>1, and b / (a+b+c+d)<0.5.

[0004] EP 0 476 963 A1 discloses a polymer blend for preparing a non-porous breathable film comprising a hydrophilic block poly(ether-co-amide) containing between about 20 and about 80 wt % PEG blocks and a hydrophobic polymer selected from a) a block poly(ether-co-amide) essentially free of PEG blocks, b) a polyamide, c) a polyester, or d) a polyurethane.

[0005] However, there remains a need to optimize the MVTR, gas permeability, and / or processability of films. More generally, there is a need for compositions for producing improved packaging materials, such as films or sheets for storing food or perishable products in ideal environments. Summary of the Invention

[0006] The present invention provides a composition comprising: (a) polyamide (PA), (b) a polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block; (c) a functionalized polyolefin, and (d) Polyolefin Including, the weight ratio of (a+b) / (c+d) is less than 1; It relates to a composition.

[0007] In some embodiments, the weight ratio of b / (a+b+c+d) is less than or equal to 0.5, typically between 0.05 and 0.5, preferably between 0.1 and 0.5, for example between 0.05 and 0.4.

[0008] The present invention addresses the above needs, and more particularly, provides suitable MVTR and gas permeability that contribute to an ideal environment in food packaging, thus improving the quality and extending the shelf life of packaged food.

[0009] This is achieved by a combination of polyamides, polymers having PA blocks and PEG blocks, functionalized polyolefins, and polyolefins. In particular, by selecting a weight ratio of polyamide (a) and polymer (b) to functionalized polyolefin (c) and polyolefin (d) of less than 1, the composition according to the present invention can advantageously provide a film with improved MVTR, gas permeability, and processability. Thus, the composition according to the present invention is particularly useful for producing films, sheets, or bags used in food packaging. Such packaging based on the composition according to the present invention can reduce wilting and prevent mold growth of fresh products, such as fruits and vegetables, enclosed therein during storage and / or transportation. DETAILED DESCRIPTION OF THE INVENTION

[0010] The invention will now be explained in more detail by the following description, without limiting it.

[0011] The composition according to the present invention comprises (a) a polyamide (PA), (b) a polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block, (c) a functionalized polyolefin, and (d) a polyolefin.

[0012] (a) Polyamide In the present application, the term "polyamide" refers to the condensation products of one or more monomers selected from amino acids or aminocarboxylic acids, lactams, and monomers resulting from the reaction of aliphatic diamines with dicarboxylic acids, and more particularly one or more amino acids, such as aminocaproic acid, amino-7-heptanoic acid, amino-11-undecenoic acid, and amino-12-dodecanoic acid; or one or more corresponding lactams, such as caprolactam, oenanlactam, and lauryllactam; or - one or more substantially stoichiometric combinations of one or more aliphatic and / or cycloaliphatic and / or aromatic-aliphatic diamines, or salts thereof, with one or more aliphatic or aromatic carboxylic diacids, or salts thereof (examples of such diamines include hexamethylenediamine, dodecamethylenediamine, metaxylylenediamine, bis(4-aminocyclohexyl)-methane (BACM), bis(3-methyl-4-amino-cyclohexyl)-methane (BMACM), and trimethylhexamethylenediamine, and examples of diacids include terephthalic acid, isophthalic acid, adipic acid, azelaic acid, sebacic acid, suberic acid, and dosedanedicarboxylic acid); or any mixture of the above monomers; and any mixture of the resulting condensation products, optionally with other polymers compatible with the polyamides; represents the condensation product of

[0013] By way of example, the polyamide (PA) may be selected from PA6, PA6.6, PA6.10, PA10.10, PA10.12, PA11, PA12, PA6.12, and PA12.12, preferably PA10.10, PA10.12, PA11, PA12, PA6.12, and / or PA12.12, where the first number indicates the number of carbon atoms in the diamine and the second number indicates the number of carbon atoms in the dicarboxylic acid, or alternatively, the only number indicates the number of carbon atoms in the repeat unit derived from an amino acid or lactam.

[0014] Preferably, the average carbon content of the repeating units of the polyamide is at least 8, preferably 8 to 14, more preferably 10 to 12.

[0015] Typically, the polyamide (PA) is selected from PA10.10, PA10.12, PA11, PA12, and PA12.12.

[0016] According to one embodiment, the polyamide (PA) of the present invention has a melting temperature below 210°C, for example below 205°C, or below 200°C.

[0017] As will be appreciated by those skilled in the art, the molecular weight of the polyamide can vary widely.

[0018] The term "average carbon content of repeating units" means the average number of carbon atoms in each repeating unit present in the polyamide, weighted by the molar ratio of said repeating unit to the total amount of polyamide blocks. For example, if the polyamide contains a single repeating unit, as in the case of PA X or PA XY as defined above, the average carbon content of the repeating units of the polyamide block is equal to the number of carbon atoms of the previous repeating unit, given that the polyamide repeating unit contains only one amide functional group in a known manner. In the case of a PA X block, the number of carbon atoms in the repeating unit is X. In the case of a PA XY block, the number of carbon atoms in the repeating unit is (X + Y) / 2, since the XY unit contains two amide functionalities.

[0019] Mixtures of polyamides are also possible.

[0020] Preferably, the polyamide (PA) in (a) is or comprises PA11 or PA12, preferably PA11. PA11 advantageously has good compatibility with polyolefins, thus providing good processability of the composition, facilitating the production of thinner films or sheets.

[0021] (b) Polymer PEBA In this application, polymers having polyamide blocks and polyether blocks are also called polyether block amides (PEBA).

[0022] A polymer (b) having a polyamide (PA) block and a polyethylene glycol (PEG) block is also called PA / PEG.

[0023] In some embodiments, polymer (b) consists of polyamide blocks and polyethylene glycol blocks.

[0024] Such polymers having PA blocks and PEG blocks are obtained by copolycondensation of polyamide sequences having reactive ends with polyether sequences having reactive ends, and include, inter alia: - diamine-terminated polyamide sequences and dicarboxylic acid-terminated polyoxyalkylene sequences; - dicarboxylic acid-terminated polyamide sequences and diamine-terminated polyoxyalkylene sequences (obtained by cyanoethylation and hydrogenation of aliphatic dihydroxy α-ω polyoxyalkylene sequences, known as polyether diols); - a diamine-terminated polyamide sequence and a polyetherdiol sequence (the resulting product is, in this particular case, a polyetheresteramide, hereinafter abbreviated as PEEA).

[0025] Such polymers are described, for example, in French Patents Nos. 74 18913 and 77 26678, and in the following U.S. Pat. Nos. 4,331,786, 4,115,475, 4,195,015, 4,839,441, 4,864,014, 4,230,838, and 4,332,920, the contents of which are incorporated herein by reference.

[0026] Dicarboxylic acid-terminated polyamide sequences can be obtained, for example, by condensing a substantially stoichiometric combination of an aminocarboxylic α-ω acid, a lactam, or a carboxylic diacid and a diamine in the presence of a chain-limiting carboxylic diacid. The polyamide blocks can be PA6, PA6.6, PA6.10, PA10.10, PA10.12, PA11, PA12, PA6.12, and PA12.12, and preferably PA10.10, PA10.12, PA11, PA12, PA6.12, PA11.12, and / or PA12.12. Preferably, the polyamide blocks are PA11 or PA12, and more preferably PA11.

[0027] Preferably, the repeating units of the polyamide blocks have an average carbon content of at least 8, preferably 8 to 14, more preferably 10 to 12.

[0028] According to one embodiment, the polyamide of the polyamide blocks in (b) is the same as the polyamide in (a).

[0029] The number-average molar mass Mn of the polyamide sequences PA varies between 300 and 15,000, preferably in the range from 600 to 5,000.

[0030] For brevity, the polyether blocks will be referred to as PEG blocks, regardless of whether they are included in the polymer chain comprising polyamide and polyether blocks in the form of diols or diamines. The number-average molar mass Mn of the polyether sequences is between 100 and 6,000, preferably between 300 and 3,000.

[0031] The number average molar mass can be determined by the chain limiter content, which can be calculated according to the following formula: M n =n 単量体 ×MW 繰り返し単位 / n 連鎖制限剤 +MW 連鎖制限剤

[0032] In this formula, n 単量体 represents the number of moles of monomer, and n 連鎖制限剤 represents the number of moles of excess (e.g., diacid) limiting agent, and MW 繰り返し単位 represents the molar mass of the repeating unit, and MW 連鎖制限剤 represents the molar mass of the excess limiting agent. The number average molar masses of the rigid and flexible blocks can be determined by gel permeation chromatography (GPC) before copolymerizing the blocks.

[0033] Polymers containing PA and PEG blocks can also contain randomly distributed moieties. Such polymers can be prepared by simultaneously reacting precursors of polyether and polyamide blocks. For example, a reaction can be induced between a polyether diol, a lactam (or the corresponding α-ω amino acid), and a chain-limiting diacid in the presence of a small amount of water. This results in polymers with essentially polyether blocks, polyamide blocks of widely varying lengths, and various randomly reacted reagents randomly distributed along the polymer chain.

[0034] The polymers having PA and PEG blocks can, for example, have a Shore D hardness typically between 20 and 75, advantageously between 30 and 70, and an intrinsic viscosity, measured in m-cresol at 20° C. and an initial concentration of 0.5% m / m, between 0.8 and 2.5.

[0035] The polymer having PA blocks and PEG blocks can be formed from 5 to 85% by weight of polyether PEG blocks (and 95 to 15% PA), preferably 20 to 80% by weight of polyether PEG blocks (and 80 to 20% PA), and more preferably 30 to 70% by weight of polyether PEG blocks (and 70 to 30% PA).

[0036] In some embodiments, polymer (b) comprises at least 30 wt. %, preferably at least 40 wt. %, and more preferably at least 50 wt. % polyethylene glycol (PEG), based on the total weight of polymer (b).

[0037] Preferably, the polymer having a PA block and a PEG block contains a single type of block. Advantageously, a polymer having a PA11 block and a PEG block (PA11 / PEG) or a polymer having a PA12 block and a PEG block (PA12 / PEG) is used. PA11 advantageously has good compatibility with polyolefins, thus providing good processability for the composition, facilitating the production of thinner films or sheets.

[0038] However, it is also possible to use blends of polymers having polyamide blocks and polyether blocks.

[0039] Such polymers having polyamide and polyether blocks are commercially available from the company ARKEMA under the trade name Pebax®, (registered trademark) or from the company EVONIK under the trade name VESTAMID®.

[0040] These polymers having PA and PEG blocks have the property of being water vapor permeable and are designated "hydrophilic" as conventionally understood by those skilled in the art.

[0041] (c) Functionalized Polyolefins In this application, the term "functionalized polyolefin" refers to a polymer of an α-olefin and a reactive unit (functional group); such reactive unit is an acid, anhydride, or epoxy functional group.

[0042] The functionalized polyolefin (c) acts as a compatibilizer or compatibilizer for compatibilizing the polyamide and the polyolefin.

[0043] Examples include polyolefins that have been pre-grafted or copolymerized or terpolymerized with unsaturated epoxides such as glycidyl (meth)acrylate, or with carboxylic acids such as (meth)acrylic acid or their salts or esters (the latter may be partially or fully neutralized with metals such as Zn), or even with carboxylic acid anhydrides such as maleic anhydride. The term "copolymerized or terpolymerized" means that the functional groups are incorporated within the main polymer chain.

[0044] The functionalized polyolefin (c) may be the following (co)polymers grafted with maleic anhydride or glycidyl methacrylate, the grafting rate being, for example, from 0.01 to 5% by weight: - PE, PP, copolymers of ethylene with propylene, butene, hexene or octene, for example containing 35 to 80% by weight of ethylene; - Copolymers of ethylene and vinyl acetate (EVA) containing up to 40% by weight of vinyl acetate; - copolymers of ethylene and alkyl (meth)acrylates, containing up to 40% by weight of alkyl (meth)acrylates; - copolymers of ethylene and vinyl acetate (EVA) and alkyl (meth)acrylates, containing up to 40% by weight of EVA and alkyl (meth)acrylates; - ethylene / propylene copolymers in which the majority of the propylene is grafted with maleic anhydride and then condensed with monoaminated polyamides (or polyamide oligomers). These products are described in EP-A-0 342 066.

[0045] The functionalized polyolefin (c) may be a copolymer or terpolymer of at least one of the following units: (1) ethylene, (2) alkyl (meth)acrylate or (meth)acrylic acid or saturated carboxylic acid vinyl ester, and (3) maleic anhydride or glycidyl (meth)acrylate.

[0046] As examples of functionalized polyolefins of the latter type, mention may be made of the following copolymers, in which ethylene preferably represents at least 60% by weight and monomer (3) represents, for example, from 0.1 to 10% by weight of the copolymer: - ethylene / alkyl (meth)acrylate or (meth)acrylic acid / maleic anhydride or glycidyl methacrylate copolymers; - ethylene / vinyl acetate / maleic anhydride or glycidyl methacrylate copolymers; - Ethylene / vinyl acetate / alkyl (meth)acrylate or (meth)acrylic acid / maleic anhydride or glycidyl methacrylate copolymers.

[0047] In the above copolymer, the (meth)acrylic acid may be present in the form of a Zn salt or a Li salt.

[0048] The term "alkyl (meth)acrylate" preferably refers to C1-C6 alkyl methacrylate and C1-C6 alkyl acrylate, which may be selected from methyl, ethyl, n-butyl, isobutyl, and 2-ethylhexyl acrylate, and most preferably methyl methacrylate and ethyl methacrylate.

[0049] Advantageously, the functionalized polyolefin (c) is or comprises an ethylene / butyl acrylate / maleic anhydride copolymer or an ethylene / ethyl acrylate / glycidyl methacrylate copolymer.

[0050] Furthermore, these polyolefins may also be crosslinked using any suitable process or agent (diepoxy, diacid, peroxy, etc.); the expression functionalized polyolefins also covers the above polyolefins crosslinked with difunctional reagents such as diacids, dianhydrides, diepoxy, etc.

[0051] The molecular weight, MFI index, and density of these functionalized polyolefins can also vary widely, as will be appreciated by those skilled in the art.

[0052] Mixtures of functionalized polyolefins are also possible.

[0053] Preferably, the functionalized polyolefin (c) is or includes a copolymer of ethylene and glycidyl methacrylate (GMA). GMA provides reactivity, e.g., toward OH, COOH, and NH, resulting in optimal dispersibility during melt blending with engineering thermoplastics such as polyamides, polyesters, and polyphenylene sulfide. As an ethylene copolymer, ethylene-GMA copolymer is compatible with LDPE in nearly all proportions and with nearly all other ethylene copolymers. Advantageously, ethylene-GMA copolymers have good compatibility with polyolefins, thus providing good processability and facilitating the production of thinner films or sheets.

[0054] (d) Polyolefin The polyolefin (d) is a homopolymer or copolymer of an α-olefin and / or diolefin, such as, for example, ethylene, propylene, butene-1, octene-1, butadiene, and the like.

[0055] Unlike the functionalized polyolefin (c), the polyolefin (d) does not contain reactive units (functional groups) such as acid, anhydride, or epoxy functional groups.

[0056] Examples include: polyethylene, in particular homopolymers such as LDPE (low density polyethylene), HDPE (high density polyethylene), LLDPE (linear low density polyethylene) or VLDPE (very low density polyethylene), polyethylene metallocene or polypropylene; - ethylene / α-olefin copolymers such as ethylene / propylene; - Ethylene propylene rubber (EPR), styrene / ethylene-butene / butadiene (SEBS), styrene / butadiene / styrene (SBS), styrene / isoprene / styrene (SIS), styrene / ethylene-propylene / styrene (SEPS), and ethylene / propylene / diene (EPDM) block copolymers; - copolymers of ethylene with at least one product chosen from salts or esters of unsaturated carboxylic acids, such as alkyl (meth)acrylates (typically methyl acrylate), or vinyl esters of saturated carboxylic acids, such as vinyl acetate, in which the proportion of comonomer can be up to 40% by weight;

[0057] The copolymers can be randomly or sequentially copolymerized and have a linear or branched structure.

[0058] The polyolefin may have, for example, a density between 0.86 and 0.965 and a melt flow index MFI between, for example, 0.3 and 40, as measured according to ASTM D1238 with a standard load of 2.16 kg and a die temperature of 190° C. The polyolefin may also be crosslinked using any suitable agent, such as an epoxy.

[0059] Mixtures of polyolefins are also possible.

[0060] Preferably, the (d) polyolefin is or comprises an ethylene-methyl acrylate copolymer or LLDPE.

[0061] composition The composition according to the present invention comprises (a) a polyamide, (b) a polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block, (c) a functionalized polyolefin, and (d) a polyolefin, as defined above.

[0062] In one embodiment, in the composition according to the invention, the weight ratio of (a) / (b) is less than 1, preferably between 0.05 and 0.95, more preferably between 0.1 and 0.5, more preferably between 0.25 and 0.45.

[0063] Preferably, the weight ratio b / (a+b+c+d) is between 0.1 and 0.5.

[0064] In some embodiments, (a) is present in an amount of 10-30% by weight, based on the total weight of (a)+(b)+(c), (b) is present in an amount of 40-80% by weight, based on the total weight of (a)+(b)+(c), and (c) is present in an amount of 10-30% by weight, based on the total weight of (a)+(b)+(c).

[0065] In one embodiment, (d) is present in an amount of 40 to 70% by weight, based on the total weight of the composition, ie, based on the total weight of (a)+(b)+(c)+(d).

[0066] In some embodiments, (a) is present in an amount of 5-15 wt.% based on the total weight of the composition, i.e., the total weight of (a)+(b)+(c)+(d), (b) is present in an amount of 15-40 wt.% based on the total weight of (a)+(b)+(c)+(d), (c) is present in an amount of 5-15 wt.% based on the total weight of (a)+(b)+(c)+(d), and (d) is present in an amount of 40-70 wt.% based on the total weight of (a)+(b)+(c)+(d).

[0067] Preferably, the composition according to the invention does not contain styrene maleic anhydride (SMA).

[0068] The compositions according to the invention may also be mixed with further additives such as fillers, pigments and / or dyes.

[0069] Method for Making the Composition The present invention also relates to a method for producing the composition according to the invention.

[0070] The method comprises: (a) polyamide (PA), (b) a polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block; (c) a functionalized polyolefin, and (d) Polyolefin blending the The weight ratio of (a+b) / (c+d) is less than 1.

[0071] Each of (a) polyamide, (b) polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block, (c) functionalized polyolefin, and (d) polyolefin is as defined above.

[0072] (a), (b), (c), and (d) can be mixed in one step, or one or more of (a), (b), (c), and (d) can be blended separately in any order.

[0073] In some embodiments, the method includes step (i) blending (a) a polyamide, (b) a polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block, and (c) a functionalized polyolefin to obtain a base polymer blend or mixture, and step (ii) blending the base polymer blend or mixture with (d) a polyolefin.

[0074] Preferably, the blend or mixture of base polymers is in the form of pellets prior to step (ii).

[0075] The blending step can be a dry mixing step of ingredients in powder form.

[0076] Alternatively, and preferably, the blending step may be a step of melt-blending some or all of the components. Melt-blending can be carried out, in particular, by compounding. For example, melt-blending can be carried out in an extruder or a co-kneader, more preferably a twin-screw extruder or a co-kneader.

[0077] The melt blending can be carried out at a temperature of from 140 to 300°C, preferably from 160 to 270°C, more preferably from 180 to 210°C.

[0078] Preferably, (d) the polyolefin is dry blended into the blend or mixture of base polymers.

[0079] At the end of the blending step, the composition can be produced in the form of, for example, flakes, crumbs, granules, or pellets, or can be further crushed or milled into a powder, or can be provided in the form of a paste.

[0080] Step (i) of blending (a), (b), and (c) to obtain a base polymer blend or mixture, and step (ii) of blending (d) into the base mixture, may be performed simultaneously or temporally separately. Specifically, step (i) can be rephrased as blending (a), (b), and (c) to obtain a base polymer blend or mixture, and step (ii) can be performed by blending (d) into the base polymer blend or mixture obtained in step (i), for example, several hours, several days, or several months before step (ii).

[0081] Kit for Obtaining the Composition The present invention also relates to a kit for obtaining a composition according to the invention.

[0082] The kit includes a first component and a second component, wherein the weight ratio of (a+b) / (c+d) is less than 1. The first component includes (a) a polyamide (PA), (b) a polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block, and (c) a functionalized polyolefin. The second component includes (d) a polyolefin.

[0083] Each of (a) polyamide, (b) polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block, (c) functionalized polyolefin, and (d) polyolefin is as defined above.

[0084] In some embodiments, the first component and the second component can each be contained, stored, or packaged in separate containers, and such separate containers of the two components can optionally be packaged together in any suitable packaging. Alternatively, the containers of the two components can be provided separately without common packaging.

[0085] Articles containing or made from the compositions and methods for making the articles The present invention also relates to articles comprising or made from compositions according to the present invention, and methods of making said articles.

[0086] The articles can be prepared using any method known in the art, such as by extrusion, injection, molding, and the like.

[0087] In some embodiments, the article is a film, sheet, or bag, preferably a film.

[0088] In some embodiments, the article is an article suitable for food packaging.

[0089] In some embodiments, the article, which is a film, sheet, or bag, preferably a film, typically has a thickness of between 5 and 500 μm, preferably between 10 and 250 μm, more preferably between 20 and 100 μm, for example, a thickness of 20 to 40 μm, or 20 to 30 μm.

[0090] In some embodiments, a method of manufacturing an article comprises the steps of: - obtaining the composition by the method defined above, and - Extruding or molding the composition into a film or sheet.

[0091] Films obtained from compositions according to the invention are non-porous and breathable, in other words permeable to water vapor but not to water, or more generally permeable to gases but not to liquids.

[0092] The articles obtained from the compositions according to the invention, especially in the form of films, exhibit improved MVTR values, measured at a thickness of 25 μm at 23° C. and a relative humidity level of 50%, from 8 to 500 g / m 2 according to the method described in ASTM standard E 96 B - Water method. 2 / 24h, preferably 10 to 500g / m 2 / 24h, preferably between 12 and 500g / m 2 / 24h. Too low an MVTR value may lead to mold growth, while too high an MVTR value may cause the fruit or vegetable to wilt. Such films create an ideal environment for packaging fresh products such as fruits and vegetables. Depending on the type of fruit or vegetable, the film can be appropriately selected based on the MVTR value.

[0093] Gas selectivity is defined as the ratio of the permeabilities of two pure gases measured separately under identical conditions. Films obtained from compositions according to the invention typically have a CO to O permeability ratio of less than 12, preferably between 4 and 10, and these values ​​are valid at 0% relative humidity (0% RH) and 23°C.

[0094] The films obtained from the compositions according to the present invention exhibit improved processability and higher tensile strength. The tensile strength (MD) can be greater than 10 MPa, preferably greater than 14 MPa, and more preferably greater than 18 MPa, as measured according to the method described in ASTM D 638 Type IV. Such films facilitate manufacturing and processing steps.

[0095] These films can be produced by any method known in the art, for example, by extrusion or molding. The films typically have a thickness of 5 to 500 μm, preferably 10 to 250 μm, more preferably 20 to 100 μm, for example, 20 to 40 μm, or 20 to 30 μm. The films can be combined with other films and / or substrates. For example, the films obtained from the compositions according to the present invention can be coextruded or laminated onto a substrate such as a grid made of polyethylene or PVC.

[0096] In some embodiments, articles made from compositions according to the present invention are used in packaging, such as food packaging and packaging for perishable products such as fruits, vegetables, fresh meat and fish fillets, etc. For example, a film obtained from a composition according to the present invention may be only a portion of the packaging, the other portion being made of any other material.

[0097] The present invention also relates to the use of the above-defined composition in food packaging.

[0098] The following examples illustrate the invention without limiting it. [Example]

[0099] The following examples illustrate the invention without limiting it.

[0100] Compositions having the blend ratios shown in Table 1 were prepared. Specifically, (a) PA, (b) PA / PEG PEBA, and (c) functionalized polyolefin were blended using a twin-screw extruder, compounded, and pelletized. The resulting pellets were blended with (d) polyolefin and extruded into a film. In Examples 12 and 13, styrene maleic anhydride (SMA) was further blended with (a) PA, (b) PA / PEG(PEBA), and (c) functionalized polyolefin, compounded, and pelletized, which were then blended with (d) polyolefin and extruded into a film. TIFF2025535135000001.tif146170

[0101] Rilsan® BESNO TL: Polyamide 11 (PA11), available from ARKEMA - PEBA: PA11 / PEG 1000 / 1500 (Mn: PA11 block with molecular weight of 1000 g / mol and PEG block with molecular weight of 1500 g / mol) Lotader® AX8840: Random copolymer of ethylene and glycidyl methacrylate (GMA), available from SK Functional Polymers Lotader® LX4110: Random terpolymer of ethylene, acrylic ester, and maleic anhydride (MAH), available from SK Functional Polymers Lotryl® 29MA03T: Ethylene-methyl acrylate random copolymer, manufactured by SK Functional Polymers - Ultzex® 2022L: Linear low density polyethylene (LLDPE), available from Prime Polymer - SMA: Styrene maleic anhydride, available from Polyscope Polymers BV

[0102] The films of Examples 1 to 16 prepared as described above were measured under the following conditions: - Equipment: GTR-30XADJ4, G2700T - Test surface: 15.2 x 10 -4 m 2 - Detection: Gas chromatography, thermal conductivity (TCD) - Temperature: 23℃ - Relative humidity: 0% - Carrier gas: Helium (pressure: 1 bar) - Diffusion gas: O2, CO2 (pressure: 1 bar each)

[0103] The CO2 and O2 permeabilities of the films were measured using gas chromatography in accordance with the method specified in JIS K7126 at a temperature of 23°C and a relative humidity of 0% for a film thickness of 25 μm. The results of the CO2 and O2 permeabilities are shown in Table 2 below in ml / m 2 It is given in units of 24h atm.

[0104] Moisture vapor transmission rate (MVTR) represents the amount of water vapor that passes through a film or structure over a 24 hour period. For 25 μm thick films prepared as described above, MVTR was measured in a Heraeus Votsch oven at 23° C. and 50% RH according to the method described in ASTM E 96 B - Water Method. MVTR results are reported in g / m² in Table 2 below. 2 It is given in units of / 24h.

[0105] Additionally, the tensile strength (MD) of the example films prepared as described above was measured using the method described in ASTM D 638 Type IV. The results are given in Table 2 below in MPa.

[0106] For the examples prepared as described above, the minimum thickness of the film was measured. Measurements were performed using a micrometer in accordance with ISO standard 4591. For purposes of this application, "minimum thickness" means the minimum thickness of film that can be continuously achieved in the film extrusion process without interruption. TIFF2025535135000002.tif87170

[0107] From Table 2, it can be seen that the films of Examples 3, 4, 7-12 provided good CO2 and O2 permeability and relatively low MVTR ranges (8 to 449) compared to the films of Comparative Examples 1, 2, 5, and 6. If the MVTR value is too high, the fruit or vegetable may wilt. The compositions according to the present invention advantageously provide films with an ideal MVTR range suitable for packaging fresh produce.

Claims

1. 1. A composition comprising: (a) polyamide (PA), (b) a polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block; (c) a functionalized polyolefin, and (d) polyolefin Including, the weight ratio of (a+b) / (c+d) is less than 1; composition.

2. 2. The composition of claim 1, wherein the weight ratio of b / (a+b+c+d) is less than or equal to 0.5, typically between 0.05 and 0.

5.

3. 3. The composition of claim 1 or 2, wherein the polyamide in (a) is or comprises PA6, PA6.6, PA6.10, PA10.10, PA10.12, PA11, PA12, PA6.12, and / or PA12.12, preferably PA10.10, PA10.12, PA11, PA12, PA6.12, PA11.12, and / or PA12.

12.

4. 4. The composition according to claim 1, wherein the polyamide blocks of polymer (b) are or comprise PA6, PA6.6, PA6.10, PA10.10, PA10.12, PA11, PA12, PA6.12, and / or PA12.12, preferably PA10.10, PA10.12, PA11, PA12, PA6.12, PA11.12, and / or PA12.

12.

5. 5. The composition according to claim 1, wherein the repeating units of polyamide (a) and / or the repeating units of the polyamide blocks of polymer (b) have an average carbon content of at least 8, preferably from 8 to 14, more preferably from 10 to 12.

6. 6. The composition of claim 1, wherein the polyamide of the polyamide blocks in (b) is the same as the polyamide in (a).

7. 7. The composition according to any one of claims 1 to 6, wherein polymer (b) comprises at least 30 wt.-%, preferably at least 40 wt.-%, more preferably at least 50 wt.-% polyethylene glycol (PEG) relative to the total weight of polymer (b).

8. 8. The composition of any one of claims 1 to 7, wherein the functionalized polyolefin in (c) is or comprises an ethylene / butyl acrylate / maleic anhydride copolymer or an ethylene / ethyl acrylate / glycidyl methacrylate copolymer, preferably a copolymer of ethylene and glycidyl methacrylate (GMA).

9. 9. The composition of any one of claims 1 to 8, wherein the polyolefin in (d) is or comprises an ethylene-methyl acrylate copolymer or LLDPE.

10. 1. A method of making a composition, comprising: (a) polyamide (PA), (b) a polymer having a polyamide (PA) block and a polyethylene glycol (PEG) block; (c) a functionalized polyolefin, and (d) polyolefin blending the the weight ratio of (a+b) / (c+d) is less than 1; method.

11. 12. The method of claim 11, comprising step (i) blending (a), (b), and (c) to obtain a base polymer blend or mixture, and step (ii) blending the base polymer blend or mixture with (d) a polyolefin.

12. 10. An article comprising or made from a composition according to any one of claims 1 to 9, preferably an article suitable for food packaging, preferably a film, sheet or bag.

13. 8 to 500 g / m2 at a thickness of 25 μm, measured at 23° C. and a relative humidity level of 50% ２ / 24h, preferably 10 to 500 g / m ２ / 24h, more preferably 12 to 500g / m ２ 13. The article of claim 12 having an MVTR of between 1 / 24 h.

14. 14. A method for producing an article according to claim 12 or 13, comprising the steps of: - obtaining the composition by the method according to claim 10 or 11, and - extruding or molding the composition into a film or sheet A method comprising:

15. Use of an article according to claim 12 or 13 for food packaging.

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