Compositions based on polyamides and polymers comprising polyamide blocks and poly (tetramethylene ether) glycol blocks

Abstract

The present invention relates to a composition comprising a polyamide, a polymer having a polyamide (PA) block and a poly (tetramethylene ether) glycol (PTMG) block, a functionalized polyolefin and a polyolefin wherein polymer (b) comprises at least 40% by weight of PTMG relative to the weight of polymer (b). The invention also relates to a method for preparing said composition, a kit for obtaining said composition, an article comprising or made from said composition, and a method for preparing said article.

Description

Technical Field

[0001] The present invention relates to a composition comprising polyamide, a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block, a functionalized polyolefin and a polyolefin. The present invention also relates to a method for preparing the composition, a kit for obtaining the composition, an article comprising or made of the composition and a method for preparing the article. Background Art

[0002] Nonporous breathable films or impermeable but breathable films are widely used in various applications. As one such application, nonporous breathable films are advantageously used for packaging, particularly food packaging, for example packaging of fresh products such as fruits, vegetables, freshly cut meat and fish. The quality and shelf life of these fresh products can be enhanced by optimizing the environment within the packaging in which they are enclosed, particularly by adjusting the moisture vapor transmission rate (MVTR), the amount of gases such as CO 2 and O 2 MVTR, also known as water vapor transmission rate (WVTR), is the amount of water vapor that passes through a substance or material in a specific period of time. For food packaging and storage, too high MVTR values ​​are undesirable because this may cause fruits or vegetables to wilt.

[0003] Document US 5959042 discloses a material for obtaining a nonporous breathable membrane, which comprises (a) a polyamide, (b) a polymer having a PA block and a polyether PEG block, (c) an optional 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] Document EP 0476963 discloses a polymer blend for preparing a non-porous breathable membrane, which comprises a hydrophilic block poly(ether-co-amide) containing about 20 to about 80 weight percent PEG blocks and a hydrophobic polymer selected from any of the following: a) a block poly(ether-co-amide) substantially free of PEG blocks, b) a polyamide, c) a polyester, or d) a polyurethane.

[0005] However, there is still a need to optimize the MVTR, gas permeability and / or processability of the film. In addition, these documents do not mention the haze or transparency of the resulting film. Haze is a measure of the scattering of light when passing through a transparent material. Since higher levels of haze result in poor transparency, haze is one of the key quality parameters of film or sheet materials in packaging applications. Therefore, there is a need for a composition that is easy to process to prepare a packaging material, such as a film or sheet, having optimized MVTR and gas permeability for preserving fresh products in an ideal environment, as well as improved haze or transparency. Summary of the invention

[0006] The present invention relates to a composition comprising:

[0007] (a) polyamide (PA),

[0008] (b) a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block,

[0009] (c) a functionalized polyolefin, and

[0010] (d) polyolefins,

[0011] Wherein polymer (b) comprises at least 40 wt. %, preferably at least 50 wt. % of PTMG relative to the weight of said polymer (b).

[0012] In some embodiments, the weight ratio of (a) / (b) is <1.5, preferably <1, more preferably <0.5, and typically between 0.2 and 0.5.

[0013] The present invention makes it possible to solve the above needs. More specifically, it provides a film or sheet with suitable MVTR and gas permeability, which contributes to an ideal environment in food packaging, thereby contributing to better quality and longer shelf life of the packaged food. In addition, it provides a film or sheet with improved haze or transparency, which is desirable in packaging applications because it does not hinder the visibility of the package contents.

[0014] This is achieved by polyamides, polymers with PA and PTMG blocks, functionalized polyolefins and combinations of polyolefins. It is noteworthy that the composition according to the invention advantageously enables the provision of films with improved qualities in terms of MVTR, gas permeability, processability and haze. Therefore, the composition according to the invention is particularly useful for preparing films, sheets or bags for food packaging. Such packaging based on the composition according to the invention can reduce wilting and prevent mold growth of fresh products (such as fruits and vegetables) encapsulated therein during storage and / or transportation. In addition, the contents of the packaging can be clearly seen through the packaging of higher transparency. DETAILED DESCRIPTION

[0015] The invention will now be described in more non-limiting detail in the following description.

[0016] The composition according to the present invention comprises (a) polyamide (PA), (b) a polymer having polyamide (PA) blocks and poly(tetramethylene ether) glycol (PTMG) blocks, (c) a functionalized polyolefin and (d) a polyolefin.

[0017] (a) Polyamide

[0018] In the present application, the term "polyamide" represents the condensation product of one or more monomers selected from amino acids or aminocarboxylic acids, lactams and monomers resulting from the reaction between aliphatic diamines and dicarboxylic acids, more specifically, the condensation product of,

[0019] - 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, enantholactam and laurolactam; or

[0020] - an essentially stoichiometric combination 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 are hexamethylenediamine, dodecamethylenediamine, meta-xylylenediamine, bis(4-aminocyclohexyl)-methane (BACM), bis(3-methyl-4-amino-cyclohexyl)-methane (BMACM) and trimethylhexamethylenediamine, examples of diacids are terephthalic acid, isophthalic acid, adipic acid, azelaic acid, sebacic acid, suberic acid and dodecanedicarboxylic acid; or

[0021] - any mixture of the above monomers; and

[0022] - Any mixtures of the condensation products obtained, optionally together with other polymers that are compatible with the polyamide.

[0023] For 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, the first number indicating the number of carbon atoms of the diamine and the second number indicating the number of carbon atoms of the dicarboxylic acid; or a single number indicating the number of carbon atoms in the repeating unit obtained from an amino acid or a lactam. The molecular weight of the polyamide may vary widely, as will be understood by those skilled in the art.

[0024] 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.

[0025] Typically, the polyamide (PA) is selected from PA6.10, PA10.10, PA10.12, PA11, PA12, PA6.12 and PA12.12.

[0026] According to one embodiment, the melting temperature of the polyamide (PA) of the present invention is less than 210°C, for example less than 205°C, or less than 200°C.

[0027] The molecular weight of the polyamide can vary widely, as will be appreciated by those skilled in the art.

[0028] The term "average carbon content of the repeating units" means the average value of the number of carbon atoms of each repeating unit present in the polyamide, weighted by the molar proportion of said repeating units relative to the total amount of the polyamide block. For example, when the polyamide comprises a single repeating unit, as in the case of PAX or PAXY as defined above, the average carbon content of the repeating units of the polyamide block is equal to the number of carbon atoms of said repeating unit, provided that the polyamide repeating unit contains only one amide functional group in a known manner. In the case of a PAX block, the number of carbon atoms of the repeating unit is X. In the case of a PAXY block, the number of carbon atoms of the repeating unit is (X+Y) / 2, since the unit XY contains two amide functional groups.

[0029] Mixtures of polyamides are also possible.

[0030] Preferably, the polyamide (PA) in (a) is or comprises PA11 or PA12, preferably PA11. PA11 advantageously has good miscibility with polyolefins, thereby providing good processability of the composition, which facilitates the manufacture of thinner films or sheets.

[0031] (b) Polymer PEBA

[0032] In the present application, polymers having polyamide blocks and polyether blocks may also be referred to as polyether block amides (PEBAs).

[0033] The polymer (b) having polyamide (PA) blocks and poly(tetramethylene ether) glycol (PTMG) blocks may also be referred to as PA / PTMG PEBA.

[0034] In some embodiments, polymer (b) consists of polyamide blocks and PTMG blocks.

[0035] This polymer having PA blocks and PTMG blocks is produced by the co-polycondensation of polyamide sequences having reactive ends and polyether sequences having reactive ends, such as:

[0036] - polyamide sequences with diamine ends and polyoxyalkylene sequences with dicarboxylic acid ends;

[0037] - polyamide sequences with dicarboxylic acid ends and polyoxyalkylene sequences with diamine ends, obtained by cyanoethylation and hydrogenation of aliphatic dihydroxy α-ω polyoxyalkylene sequences, known as polyether diols;

[0038] - polyamide sequences with diamine ends and polyetherdiol sequences, in this particular case the product obtained is a polyetheresteramide (hereinafter abbreviated to PEEA).

[0039] Such polymers are described, for example, in French Patent Serial Nos. 74 189 13 and 77 266 78 and in the following U.S. Patent 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.

[0040] Polyamide sequences with dicarboxylic acid ends are obtained, for example, from the condensation of a substantially stoichiometric combination of aminocarboxylic α-ω acids, lactams or carboxylic diacids and diamines in the presence of chain-limiting carboxylic diacids. The polyamide blocks may be 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, PA11.12 and / or PA12.12. Preferably, the polyamide blocks are PA11 or PA12, preferably PA11.

[0041] Preferably, the average carbon content of the repeating units of the polyamide blocks is at least 8, preferably 8 to 14, more preferably 10 to 12.

[0042] According to one embodiment, the polyamide of the polyamide blocks in (b) is the same as the polyamide in (a).

[0043] The number-average molar mass Mn of the polyamide sequences PA varies between 300 and 15,000, preferably between 600 and 5,000.

[0044] Regardless of whether the polyether blocks are contained in the polymer chain with polyamide blocks and polyether blocks in the form of diols or in the form of diamines, for simplicity they will be referred to as PTMG blocks.The number average molar mass Mn of the polyether sequences is from 100 to 6,000, preferably from 300 to 3,000.

[0045] The number-average molar mass can be set via the content of chain limiters. It can be calculated according to the following equation:

[0046] Mn=n 单体 × Mw 重复单元 / n 链限制剂 +Mw 链限制剂

[0047] In this formula, n 单体 represents the number of moles of monomer, n 链限制剂 represents the number of moles of excess limiting agent (e.g. diacid), Mw 重复单元 represents the molar mass of the repeating unit, and Mw 链限制剂 represents the molar mass of the excess limiting agent. The number average molar mass of the hard block and the soft block can be measured by gel permeation chromatography (GPC) before block copolymerization.

[0048] Polymers with PA blocks and PTMG blocks may also contain randomly distributed parts. Such polymers can be prepared by reacting precursors of polyether and polyamide blocks simultaneously. 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. The polymer obtained essentially has polyether blocks, polyamide blocks of widely varying lengths, and various reagents that have reacted randomly and are randomly distributed along the polymer chain.

[0049] The polymer having PA blocks and PTMG blocks may have, for example, a Shore D hardness typically comprised between 20 and 75 and advantageously between 30 and 70, and an intrinsic viscosity comprised between 0.8 and 2.5, measured in m-cresol at 20° C. for an initial concentration of 0.5% m / m.

[0050] Polymers having PA blocks and PTMG blocks may be formed from 5 to 85 wt % polyether PTMG blocks (and 95 to 15 wt % PA), and preferably 20 to 80 wt % polyether PTMG blocks (and 80 to 20 wt % PA), and more preferably 30 to 70 wt % polyether PTMG blocks (and 70 to 30 wt % PA).

[0051] Preferably, the polymer having a PA block and a PTMG block comprises a single type of block. Advantageously, a polymer having a PA11 block and a PTMG block (PA11 / PTMG PEBA), or a polymer having a PA12 block and a PTMG block (PA12 / PTMG PEBA) is employed. PA11 advantageously has good miscibility with polyolefins, thus providing good processability of the composition, which helps to manufacture thinner films or sheets.

[0052] In some embodiments, in addition to the PA block and the PTMG block, the polymer (b) may also include a polyethylene (PE) block other than PTMG. For example, the polymer (b) may further include polyethylene glycol (PEG), polypropylene glycol (PPG) and / or poly (oxytrimethylene) glycol (PO3G) blocks.

[0053] In this case, polymer (b) comprises at least 40% by weight, preferably at least 50% by weight, or at least 60%, or at least 90% by weight of PTMG relative to the total weight of polymer (b).

[0054] However, it is also possible to use blends of polymers having polyamide blocks and polyether blocks.

[0055] Such polymers having polyamide blocks and polyether blocks are commercially available under the trade names Pebax®, ® from ARKEMA or under the trade name VESTAMID® from EVONIK.

[0056] (c) Functionalized polyolefins

[0057] In the present application, the term "functionalized polyolefin" means a polymer of an alpha-olefin and a reactive unit (functional group); such reactive unit is an acid, anhydride or epoxy functional group.

[0058] The functionalized polyolefin (c) is used as a compatibilizer or a compatibilizer for compatibilizing polyamide and polyolefin.

[0059] As examples, we can cite polyolefins previously grafted or copolymerized or terpolymerized with unsaturated epoxides such as glycidyl (meth)acrylate, or with carboxylic acids or corresponding salts or esters such as (meth)acrylic acid (the latter can be partially or completely neutralized with metals such as Zn, etc.), or further with carboxylic anhydrides such as maleic anhydride. The term "copolymerized or terpolymerized" means that the functional groups are then integrated into the polymer backbone.

[0060] Functionalized polyolefins (c) may be the following (co)polymers grafted with maleic anhydride or glycidyl methacrylate, wherein the grafting rate is, for example, 0.01 to 5% by weight:

[0061] PE, PP, copolymers of ethylene with propylene, butene, hexene or octene, containing, for example, 35 to 80% by weight of ethylene;

[0062] - copolymers of ethylene and vinyl acetate (EVA) containing up to 40% by weight of vinyl acetate;

[0063] - copolymers of ethylene and alkyl (meth)acrylate containing up to 40% by weight of alkyl (meth)acrylate;

[0064] - copolymers of ethylene and vinyl acetate (EVA) and alkyl (meth)acrylates, containing up to 40% by weight of EVA and alkyl (meth)acrylates;

[0065] - Ethylene / propylene copolymers having a major part of the propylene grafted with maleic anhydride and then condensed with a monoaminated polyamide (or polyamide oligomer). These products are described in EP 0342066.

[0066] The functionalized polyolefin (c) may also be a copolymer or terpolymer of at least one of the following units: (1) ethylene, (2) an alkyl (meth)acrylate or a vinyl (meth)acrylic acid or a saturated carboxylic acid ester and (3) maleic anhydride or glycidyl (meth)acrylate.

[0067] 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 of the copolymer, and in which monomer (3) represents, for example, from 0.1 to 10% by weight of the copolymer:

[0068] - ethylene / alkyl (meth)acrylate or (meth)acrylic acid / maleic anhydride or glycidyl methacrylate copolymers;

[0069] - ethylene / vinyl acetate / maleic anhydride or glycidyl methacrylate copolymers;

[0070] - Ethylene / vinyl acetate / alkyl (meth)acrylate or (meth)acrylic acid / maleic anhydride or glycidyl methacrylate copolymers.

[0071] In the above copolymer, (meth)acrylic acid may be present in the form of a Zn or Li salt.

[0072] The term "alkyl (meth)acrylate" preferably represents C 1 To C 6 Alkyl esters and may be selected from methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate and 2-ethylhexyl acrylate, and most preferably methyl methacrylate and ethyl methacrylate.

[0073] Advantageously, the functionalized polyolefin (c) is or comprises an ethylene / butyl acrylate / maleic anhydride copolymer or an ethylene / ethyl acrylate / glycidyl methacrylate copolymer.

[0074] Furthermore, these polyolefins may also be crosslinked using any suitable method or agent (diepoxides, diacids, peroxides, etc.); the expression functionalized polyolefin also encompasses the above polyolefins crosslinked with difunctional agents such as diacids, dianhydrides, diepoxides, and the like.

[0075] 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.

[0076] Mixtures of functionalized polyolefins are also possible.

[0077] Preferably, the functionalized polyolefin (c) is or comprises a copolymer of ethylene and glycidyl methacrylate (GMA). For example, GMA gives 2 The reactivity of ethylene-GMA copolymers leads to optimal dispersion during melt mixing with engineering thermoplastics such as polyamides, polyesters, and polyphenylene sulfide. As ethylene copolymers, ethylene-GMA copolymers are compatible with LDPE in essentially all proportions and with almost all other ethylene copolymers. Ethylene-GMA copolymers advantageously have good miscibility with polyolefins, thereby providing good processability, which is conducive to the manufacture of thinner films or sheets.

[0078] (d) Polyolefins

[0079] The polyolefin (d) is a homopolymer or copolymer of an α-olefin and / or a diene (eg ethylene, propylene, butene-1, octene-1, butadiene).

[0080] The polyolefin (d) which is different from the functionalized polyolefin (c) does not contain any reactive units (functional groups) which are acid, anhydride or epoxide functions.

[0081] Examples are:

[0082] - homopolymers such as polyethylene, in particular LDPE (low-density polyethylene), HDPE (high-density polyethylene), LLDPE (linear low-density polyethylene) or VLDPE (very low-density polyethylene), polyethylene metallocene or polypropylene;

[0083] - ethylene / α-olefin copolymers, such as ethylene / propylene;

[0084] - ethylene propylene rubber (EPR), styrene / ethylene-butylene / butadiene (SEBS), styrene / butadiene / styrene (SBS), styrene / isoprene / styrene (SIS), styrene / ethylene-propylene / styrene (SEPS) and ethylene / propylene / diene (EPDM) block copolymers;

[0085] - copolymers of ethylene and at least one product chosen from unsaturated carboxylates, 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 may be up to 40% by weight.

[0086] The above copolymers may be copolymerized in a random or sequential manner and have a linear or branched structure.

[0087] According to ASTM D1238, at a standard load of 2.16 kg and a mold temperature of 190° C., the polyolefin may have, for example, a density comprised between 0.86 and 0.965 and a melt flow index MFI comprised, for example, between 0.3 and 40. The polyolefin may also be crosslinked using any suitable agent (epoxy, etc.).

[0088] Polyolefin mixtures are also possible.

[0089] Preferably, the polyolefin in (d) is or comprises ethylene-methyl acrylate copolymer or LLDPE.

[0090] Composition

[0091] The composition according to the invention comprises (a) a polyamide, (b) a polymer having polyamide (PA) blocks and poly(tetramethylene ether) glycol (PEG) blocks, (c) a functionalized polyolefin, and (d) a polyolefin, as defined above.

[0092] In some embodiments, in the composition, the ratio of the amount by weight of (a) to the amount by weight of (b), i.e., a / b, is less than 1.5, typically less than 1, such as 0.05 to 0.95, preferably 0.1 to 0.5, more preferably 0.25 to 0.45.

[0093] In some embodiments, the weight ratio of (b) / (c) is <4.

[0094] In some embodiments, (a) is present in an amount of 10-30 wt % relative to the total weight of (a) + (b) + (c), (b) is present in an amount of 40-80 wt % relative to the total weight of (a) + (b) + (c), and (c) is present in an amount of 10-30 wt % relative to the total weight of (a) + (b) + (c).

[0095] In some embodiments, in the composition, (d) is present in an amount of 40-70 wt % relative to the total weight of the composition, ie relative to the total weight of (a)+(b)+(c)+(d).

[0096] In some embodiments, (a) is present in an amount of 4-20 wt % relative to the total weight of the composition (i.e., the total weight of (a) + (b) + (c) + (d)), (b) is present in an amount of 15-70 wt % relative to the total weight of (a) + (b) + (c) + (d), (c) is present in an amount of 5-20 wt % relative to the total weight of (a) + (b) + (c) + (d), and (d) is present in an amount of 5-70 wt % relative to the total weight of (a) + (b) + (c) + (d).

[0097] Preferably, the composition according to the invention does not contain styrene maleic anhydride (SMA).

[0098] The compositions according to the invention may also be mixed with further additives, such as fillers, pigments and / or dyes.

[0099] Method for preparing the composition

[0100] The present invention also relates to a process for preparing a composition according to the invention, comprising the steps of blending:

[0101] (a) polyamide (PA),

[0102] (b) a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block,

[0103] (c) a functionalized polyolefin, and

[0104] (d) polyolefins,

[0105] Wherein polymer (b) comprises at least 40 wt. %, preferably at least 50 wt. % of PTMG relative to the weight of said polymer (b).

[0106] The method comprises the steps of blending (a) a polyamide, (b) a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block, (c) a functionalized polyolefin, and (d) a polyolefin.

[0107] Each of (a) polyamide, (b) polymer having polyamide (PA) blocks and poly(tetramethylene ether) glycol (PTMG) blocks, (c) functionalized polyolefin, and (d) polyolefin are those defined above.

[0108] (a), (b), (c) and (d) may be blended together in one step. Alternatively, one or some of (a), (b), (c) and (d) may be blended separately in any order.

[0109] In some embodiments, the method includes the step (i) of blending (a) a polyamide, (b) a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block, and (c) a functionalized polyolefin to obtain a base polymer blend or mixture, and the step (ii) of blending (d) a polyolefin into the base polymer blend or mixture of step (i).

[0110] Preferably, the base polymer blend or mixture is in pellet form prior to step (ii).

[0111] The blending step may be a step of dry blending the components in powder form.

[0112] Alternatively and preferably, the blending step may be a step of melt blending some or all of the components. Melt blending may be performed in particular by admixture. For example, melt blending may be performed in an extruder or a co-kneader, more preferably a twin screw extruder or a co-kneader.

[0113] The melt blending may be performed at a temperature of 140 to 300°C, preferably 160 to 270°C, more preferably 180 to 210°C.

[0114] Preferably, the (d) polyolefin is dry blended into the base polymer blend or mixture.

[0115] At the end of the blending step, the composition can be produced, for example, in the form of flakes, crumbs, granules or pellets. Alternatively, it can be further milled or ground into a powder. It can also be provided in the form of a paste.

[0116] The step (i) of blending (a), (b) and (c) to obtain a base polymer blend or mixture and the step (ii) of blending (d) into the base mixture can be performed simultaneously or in a time-separated manner. Specifically, step (i) can be rewritten as a step of obtaining a base polymer blend or mixture by blending (a), (b) and (c), and step (ii) can be performed by blending (d) into the base polymer blend or mixture previously obtained by step (i) (e.g., a few hours, days or months before step (ii)).

[0117] Kit for obtaining a composition

[0118] The invention also relates to a kit for obtaining the composition according to the invention.

[0119] The kit comprises a first component and a second component. The first component comprises (a) polyamide (PA), (b) a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block, and (c) a functionalized polyolefin, preferably the amount of (a) by weight is less than the amount of (b) by weight. The second component comprises (d) polyolefin, preferably the amount of (d) relative to the amount of Reagents box The total weight of the composition obtained is 5-70 wt%.

[0120] Each of (a) polyamide, (b) polymer having polyamide (PA) blocks and poly(tetramethylene ether) glycol (PTMG) blocks, (c) functionalized polyolefin, and (d) polyolefin are those defined above.

[0121] In some embodiments, the first component and the second component can be contained, stored or packaged in separate containers, respectively, and such separate containers of the two components can optionally be packaged together by any suitable packaging form. Alternatively, the containers of the two components can be provided separately without any common packaging.

[0122] Articles containing or made from the composition and methods for preparing the article

[0123] The invention also relates to an article comprising or made from a composition according to the invention, and a method for producing said article.

[0124] The articles can be prepared using any method known in the art, such as by extrusion, injection, molding, and the like.

[0125] In some embodiments, the article is a film, a sheet, or a bag, preferably a film.

[0126] In some embodiments, the article is an article suitable for food packaging.

[0127] In some embodiments, the thickness of the article as a film, sheet or bag (preferably a film) is generally 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.

[0128] In some embodiments, the method of making an article comprises the steps of:

[0129] - a composition obtained by a process as defined above; and

[0130] - Extruding or molding the composition into a film or sheet.

[0131] The films obtained from the composition according to the invention are non-porous and breathable, in other words they are permeable to water vapour but impermeable to water and, more generally, permeable to gases but impermeable to liquids.

[0132] The articles obtained from the composition according to the invention, in particular in the form of films, give improved MVTR values. The improved MVTR values ​​may be higher than 4 g / m2 / 24h, preferably between 4 and 500 g / m2 / 24h, more preferably between 4 and 200 g / m2 / 24h, measured at 23°C, for a relative humidity level of 50%, at a thickness of 25 μm, following the method described in ASTM standard E 96 B-Water method. Such films enable an ideal environment to be achieved in the packaging of fresh products such as fruits and vegetables.

[0133] The gas selectivity is defined as the ratio of the permeabilities of two pure gases, respectively measured under the same conditions.2 With O 2 The permeability ratio is typically below 12 and preferably between 4 and 10, these values ​​being valid at 0% relative humidity (0% RH) and 23°C.

[0134] The articles obtained by the composition according to the present invention, in particular articles in the form of films, give improved haze values. According to ASTM D1003-97 procedure B, at a thickness of 25 μm, using a spectrophotometer (Konica Minolta model CM-3610d) with a wavelength range of 360 to 740 nm and a wavelength spacing of 10 nm in the transmittance and haze mode, measured under standard light source A and an angle of 10 degrees, the improved haze value can be less than 50%, preferably less than 40%, more preferably less than 30%. This film is advantageously used for packaging with higher transparency.

[0135] These films can be prepared using any method known in the art, for example by extrusion or molding. The thickness of the film is generally 5 to 500 μm, preferably 5 to 250 μm, more preferably 10 to 100 μm, preferably 15 to 60 μm. The film can be associated with other films and / or carriers. For example, the film obtained by the composition according to the invention can be coextruded or laminated on a carrier (for example a mesh made of polyethylene or PVC).

[0136] In some embodiments, the articles made from the compositions according to the invention are used for packaging, such as food packaging and packaging for fresh products (e.g., fruits, vegetables, freshly cut meat and fish). For example, the film obtained from the compositions according to the invention can be only a part of the packaging, the other parts being made from any other material.

[0137] The invention also relates to the use of a preparation as defined above for food packaging.

[0138] The following examples illustrate the present invention without limiting it.

[0139] Example

[0140] The following examples illustrate the present invention without limiting it.

[0141] Compositions having the blending ratios summarized in Table 1 were prepared. Specifically, (a) PA, (b) PEBA and (c) functionalized polyolefin were blended and mixed into pellets using a twin-screw extruder. The resulting pellets were blended with (d) polyolefin and extruded into films.

[0142] Table 1

[0143]

[0144] Unit: Weight%

[0145] - Rilsan® BESNO TL: polyamide 11 (PA11), available from ARKEMA

[0146] PEBA 1: PA11 / PTMG 1000 / 1000 (Mn: PA11 block with a molecular weight of 1000 g / mol and PTMG block with a molecular weight of 1000 g / mol), containing 50% by weight of PTMG relative to the weight of PEBA 1

[0147] PEBA 2: PA11 / PEG 1000 / 1500 (Mn: PA11 block with a molecular weight of 1000 g / mol and PEG block with a molecular weight of 1500 g / mol), containing 60% by weight of PEG relative to the weight of PEBA 2

[0148] PEBA 3: PA11 / PTMG 600 / 1000 (Mn: PA11 block with a molecular weight of 600 g / mol and PTMG block with a molecular weight of 1000 g / mol), containing 60% by weight of PTMG relative to the weight of PEBA 3

[0149] - Lotader® AX8840: a random copolymer of ethylene and glycidyl methacrylate (GMA), available from SK functional polymer

[0150] - Lotryl® 29MA03T: Random ethylene-methyl acrylate copolymer from SK functional polymer

[0151] -Ultzex® 2022L: Linear low-density polyethylene (LLDPE), available from Prime Polymer

[0152] For the films of Examples 1-16 prepared as above, measurements were performed under the following conditions:

[0153] -Machine: GTR-30XADJ4, G2700T

[0154] -Test surface: 15.2 x 10 -4 m²

[0155] -Detection: gas chromatography, thermal conductivity (TCD)

[0156] - Temperature: 23℃

[0157] -Relative humidity: 0%

[0158] -Carrier gas: helium (pressure: 1 bar)

[0159] -Diffusion gas: O 2 , CO 2 (Pressure: 1 bar each)

[0160] The film's CO absorption was measured at a film thickness of 25 μm using gas chromatography at a temperature of 23° C. and a relative humidity of 0% according to the method described in JIS K7126. 2 and O 2 The permeability of CO 2 and O 2 The results for the permeability are given in Table 2 below in ml / m² / 24h atm.

[0161] Moisture Vapor Transmission Rate (MVTR) indicates the amount of water vapor that passes through a film or structure over a period of 24 hours. For a 25 μm thick film prepared as above, MVTR was measured in a Heraeus Votsch oven at 23°C, 50% RH according to the method described in ASTM E 96B-Water Method. The results of MVTR are given in Table 2 below in g / m² / 24h.

[0162] In addition to the above Examples 1-16, for a 25 μm thick pure LLDPE film as a comparative example, the MVTR was measured according to the same method as above. The pure LLDPE film was prepared from 100 wt% Ultzex® 2022L. The measured MVTR (25 μm, B method) was 2 g / m² / 24h.

[0163] In addition, haze was measured for the film (25 μm) prepared as above using a spectrophotometer (Konica Minolta Model CM-3610d) in transmittance and haze mode, at a wavelength range of 360 to 740 nm and a wavelength spacing of 10 nm, under standard illuminant A and at an angle of 10 degrees according to ASTM D1003-97 Procedure B. The results of haze are given in % in Table 2 below.

[0164] Table 2

[0165]

[0166] As can be seen from Table 2, the films of Examples 1-8 provide MVTR results within a lower and defined range (4.2 to 189), while the MVTR results of the films of Comparative Examples 9-14 vary over a wide range of 67 to 3135. Excessively high MVTR values ​​are undesirable because they may cause fruits or vegetables to wilt. The films of Examples 1-8 also provide a lower and defined haze range (13 to 28) compared to the films of Examples 9-14 (46 to 63) and the films of Examples 15-18 (36 to 55).

[0167] Thus, the composition according to the present invention advantageously provides a film having good clarity and an ideal MVTR range for packaging fresh produce. In other words, the composition according to the present invention enables improved control of the MVTR and haze of the film.

[0168] In addition, it can be seen from Examples 9-14 that PA / PEG-PEBA-based films require a larger proportion of polyolefin (d) blended to achieve a reduced MVTR range. In contrast, as seen from Examples 1-8, the PA / PTMG PEBA-based composition according to the present invention achieves a relatively low range of MVTR for a wider range of polyolefins from 5% to 70%. Thus, the composition according to the present invention allows a wider range of choices for polyolefins to be blended. The ratio of polyolefins to be blended can be flexibly increased or decreased according to the application or need, while still achieving the expected quality of MVTR and haze. For example, the ratio of bio-based or plant-based materials as PA / PTMG PEBA can be increased to make a highly transparent and non-porous breathable film.

[0169] In other words, the composition according to the present invention enables film properties to be easily optimized and controlled within appropriate ranges of MVTR and haze. The proportion of the polyolefin (d) to be blended can be selected from a wider range according to needs or applications. The polyolefin (d) can be blended to the base polymer mixture by an easy method (e.g., by dry blending). In this way, film properties, such as MVTR and haze, can be more easily controlled and optimized.

Claims

1. A composition comprising: (a) polyamide (PA), (b) a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block, (c) a functionalized polyolefin, and (d) polyolefins, Wherein polymer (b) comprises at least 40 wt. %, preferably at least 50 wt. % of PTMG relative to the weight of said polymer (b).

2. A composition according to claim 1, wherein the weight ratio of (a) / (b) is <1.5, preferably <1, more preferably <0.5, typically between 0.2 and 0.

5.

3. The composition according to any one of the preceding claims, 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 PA11 and / or PA12.

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

5. The composition according to any one of the preceding claims, wherein the average carbon content of the repeating units of the polyamide (a) and / or the polyamide blocks in the polymer (b) is at least 8, preferably 8 to 14, more preferably 10 to 12.

6. The composition according to any one of the preceding claims, wherein the polyamide of the polyamide blocks in (b) is the same as the polyamide in (a).

7. A composition according to any one of the preceding claims, 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).

8. A composition according to any one of the preceding claims, wherein the polyolefin in (d) is or comprises a copolymer of ethylene and methyl acrylate or a linear low density polyethylene (LLDPE).

9. The composition according to any one of the preceding claims, wherein (d) is present in an amount of 5 to 70% by weight relative to the total weight of the composition.

10. A method for preparing a composition comprising the steps of blending: (a) polyamide (PA), (b) a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block, (c) a functionalized polyolefin, and (d) polyolefins, Wherein polymer (b) comprises at least 40 wt. %, preferably at least 50 wt. % of PTMG relative to the weight of said polymer (b).

11. The method according to claim 10, wherein the blending step The following steps are involved: (i) blending (a) a polyamide, (b) a polymer having a polyamide (PA) block and a poly(tetramethylene ether) glycol (PTMG) block, and (c) a functionalized polyolefin to obtain a base polymer blend or mixture; and (ii) blending (d) a polyolefin into the base polymer blend or mixture of step (i).

12. An article comprising or made of the composition according to any one of claims 1 to 9, preferably the article is a film, a sheet or a bag.

13. The article according to claim 12, wherein the article has an MVTR of 4 to 500 g / m2 / 24h, preferably 4 to 200 g / m2 / 24h and / or a haze of less than 50%, preferably less than 40%, more preferably less than 30% at a thickness of 25 μm, the MVTR being measured at a thickness of 25 μm at 23°C for a relative humidity level of 50%.

14. A method for preparing a product according to claim 12 or 13, wherein The following steps are involved: - the composition is obtained by the method according to any one of claims 10 to 11; and - Extruding or molding the composition into a film or sheet.

15. Use of the preparation according to any one of claims 1 to 10 for food packaging.

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