Multilayer film and uses thereof

Abstract

The present invention relates to a multilayer film, comprising: - an adhesive layer A comprising at least one polyolefin modified by a carboxylic acid and / or by one of the derivatives of same; - an intermediate layer C comprising at least one styrene block copolymer; and - a barrier layer B comprising at least one thermoplastic polyester elastomer; and to the uses of same.

Description

[0001] Multilayer film and its uses

[0002] FIELD OF INVENTION

[0003] The present invention relates to a multilayer film and its uses, in particular for the preparation of laminates.

[0004] TECHNOLOGICAL BACKGROUND

[0005] Various single- or multi-layer films, formulated from different polymers, are commercially available for bonding various substrates such as foams, metals, textiles, or plastics. The polymers are typically polyamides, polyolefins, polyamide / polyester copolymers, thermoplastic polyesters, etc.

[0006] In the automotive sector, multilayer films can be used for bonding interior parts such as headliners, seat upholstery, decorative trim pieces, and soundproofing components (car floor mats, trunk floor, engine hood, etc.). These films must be durable and withstand various operating conditions, particularly exposure to high temperatures (parts near the engine).

[0007] Therefore, there is a need for new multilayer films with good mechanical and adhesive properties over time.

[0008] In particular, there is a need for new multilayer films that exhibit good cohesion after extrusion and do not delaminate over time.

[0009] In particular, there is a need for new multilayer films with good temperature resistance (for example, at a temperature greater than or equal to 120°C).

[0010] In particular, there is a need for new multilayer films that are easy to prepare and inexpensive.

[0011] DESCRIPTION OF THE INVENTION

[0012] The present invention relates to a multilayer film comprising: an adhesive layer A comprising at least one polyolefin modified by a carboxylic acid and / or by one of its derivatives; an intermediate layer C comprising at least one styrenic block copolymer; a barrier layer B comprising at least one thermoplastic polyester elastomer.

[0013] The multilayer film according to the invention advantageously exhibits good mechanical and adhesive properties over time. The multilayer film according to the invention also advantageously exhibits good cohesion after extrusion.

[0014] The multilayer film according to the invention also exhibits good temperature resistance (for example at a temperature greater than or equal to 120°C).

[0015] The multilayer film according to the invention can advantageously be prepared using a simple and inexpensive process.

[0016] The multilayer film according to the invention can advantageously be used in many applications, such as for example in the automotive field (engine hood for example).

[0017] The multilayer film according to the invention advantageously allows the bonding of various polar and non-polar substrates.

[0018] The multilayer film according to the invention advantageously demonstrates good cohesion between layers A and B without delamination.

[0019] Multilayer film

[0020] Adhesive layer

[0021] The adhesive layer A comprises at least one polyolefin modified by a carboxylic acid and / or by one of its derivatives.

[0022] The term "modified polyolefin" means either a copolymer of olefins and said carboxylic acid and / or derivatives, or a homopolymer or copolymer of olefin grafted by said carboxylic acid and / or derivatives.

[0023] Preferably, the polyolefin is a homopolymer or copolymer grafted by a carboxylic acid and / or one of its derivatives.

[0024] Preferably, the content of carboxylic acid and / or one of its derivatives shall be from 0.1% to 2.0% by weight relative to the total weight of said modified polyolefin.

[0025] Derivatives of carboxylic acids include, in particular, esters, amides, salts, imides and anhydrides of said acids.

[0026] The carboxylic acid is preferably chosen from the group consisting of acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, and mixtures thereof.

[0027] Carboxylic acid derivatives are preferably chosen from maleic anhydride, itaconic anhydride, dimethyl maleic anhydride.

[0028] Preferably, the adhesive layer A comprises at least one polyolefin modified (more preferably grafted) with maleic acid or maleic anhydride, more preferably maleic anhydride. Even more preferably, the total content of maleic acid or maleic anhydride ranges from 0.1% to 2% by weight relative to the total weight of said modified polyolefin.

[0029] Polyolefins modified by a carboxylic acid and / or one of its derivatives can be synthesized by classical methods known to those skilled in the art, such as, for example, radical polymerization, metallocene-catalyzed polymerization, or polymerization in the presence of a Ziegler-Natta catalyst.

[0030] Homopolymers (or copolymers) of grafted olefins can be prepared by reacting a pre-formed polyolefin with the compound to be grafted by heating, with or without a free-radical-generating catalyst (such as an organic peroxide) and with or without a solvent. None of the constituent atoms of the grafted radical, often added by a radical reaction, are incorporated into the main chain of the polyolefin. The grafted radical is notably linked, as a pendant group, to certain repeating units of the main polyolefin chain. The grafted polyolefin can be either a homopolymer or a copolymer.

[0031] Polyolefin can be a homopolymer of C2-C20 alpha-olefins; preferably, polyolefin is selected from polyethylenes, polypropylenes, polybutylenes, and mixtures thereof.

[0032] Polyethylenes can include linear polyethylenes such as, for example, HDPE (High Density Polyethylene), linear low-density polyethylene (LLDPE), very low or ultra-low density polyethylene (VLDPE or ULDPE), and branched polyethylenes such as, for example, low-density polyethylene.

[0033] Polyolefin can be a copolymer of ethylene with a C3-20 alpha-olefin comonomer, or a copolymer of propylene with a C4-C20 alpha-olefin comonomer.

[0034] C3-C20 alpha-olefins can be selected from the group consisting of propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-octadecene and mixtures thereof.

[0035] C4-C20 alpha-olefins can be selected from the group consisting of 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-octadecene and mixtures thereof.

[0036] The modified polyolefin can have a melt flow index (MFI) measured at 190°C and under a total weight of 2.16 kg, in accordance with ISO 1133, ranging from 0.5 g / 10 min to 30 g / 10 min.

[0037] The modified polyolefin can have a density ranging from 0.6 to 1.2 g / cm3, preferably from 0.7 to 1.0 g / cm3. The density is preferably measured according to ISO 1133.

[0038] The modified polyolefin preferably has a melting point of 100°C to 150°C. The melting point can be measured according to ASTM D3418. Polyolefins modified according to the invention are, for example, commercially available from LyondelIBasell, for example under the name Plexar™, or from Mitsui under the name Admer™, or Bynel 4206 marketed by DuPont (maleic anhydride modified LLDPE), or Orevac® 18360 marketed by Arkema (maleic anhydride grafted LLDPE).

[0039] Preferably, the adhesive layer A comprises a modified polyethylene (even more preferably grafted) with maleic anhydride.

[0040] The adhesive layer A preferably comprises more than 90% by weight of at least one modified polyolefin as defined above, preferably more than 95% by weight, and even more advantageously more than 99% by weight relative to the total weight of said adhesive layer.

[0041] The adhesive layer can have a total thickness ranging from 5 to 60 jm, preferably from 15 to 50 n, and even more preferably from 20 to 40 jm.

[0042] Barrier layer

[0043] The barrier layer comprises a thermoplastic polyester elastomer.

[0044] The barrier layer helps to protect the bonded substrate and to make it impermeable to certain gases (example: air) and fluids (example: water).

[0045] The term "thermoplastic polyester elastomer" is well known to those skilled in the art, and is also referred to by the acronym "TPC". It is a block copolymer comprising alternating blocks or segments called hard or rigid, and blocks or segments called soft or flexible, with ester bonds in the hard blocks, and possibly ester and / or ether and / or carbonate bonds in the soft blocks.

[0046] Thermoplastic polyester elastomer can be of the polyester-polyester type (with the soft segment including a polyester) or polyester-polyether type (with the soft segment including a polyether) or polyester-polyester / polyether type (with the soft segment including a polyester-polyether copolymer).

[0047] A thermoplastic polyester-polyester elastomer may comprise an aromatic polyester as the hard segment and an aliphatic polyester as the soft segment.

[0048] A thermoplastic polyester-polyether elastomer may comprise an aromatic polyester as the hard segment and an aliphatic polyether as the soft segment.

[0049] The hard segment of a thermoplastic polyester elastomer can be a segment comprising a polyester formed from an aromatic polyester prepared, for example, from an aromatic dicarboxylic acid and a diol. Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, anthracene dicarboxylic acid, diphenyl-4,4-dicarboxylic acid, diphenoxyethanedicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 5-sulfoisophthalic acid, and sodium 3-sulfoisophthalate.

[0050] Aromatic polyester can be prepared from a single or a mixture of aromatic dicarboxylic acids.

[0051] The diol may be chosen from those having a molar mass less than or equal to 400 g / mol. It may, for example, be chosen from: aliphatic diols such as, for example, 1,4-butanediol, ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, decamethylene glycol or mixtures thereof; aromatic diols such as, for example, xylylene glycol, bis(p-hydroxy)diphenyl, bis(p-hydroxy)diphenylpropane, 2,2'-bis[4-(2-hydroxyethoxy)phenyl]propane, bis[4(2-hydroxyethoxy)phenyl]sulfone, 1,1-bis[4-(2-hydroxyethoxy)phenyl]cyclohexane, 4,4'-hydroxy-p-terphenyl, or mixtures thereof; mixtures thereof.

[0052] Aromatic polyester is preferably prepared from an aromatic dicarboxylic acid such as terephthalic acid, and an aliphatic diol such as 1,4-butanediol.

[0053] According to a preferred mode, the hard segment of the thermoplastic polyester elastomer comprises a polyester selected from polybutylene terephthalate, polyethylene terephthalate and polytrimethylene terephthalate, and even more preferably polybutylene terephthalate.

[0054] The soft segment of the thermoplastic polyester elastomer may comprise an aliphatic polyether and / or an aliphatic polyester, preferably an aliphatic polyether.

[0055] The aliphatic polyether can be a poly(ethylene oxide) glycol, a poly(propylene oxide) glycol, a poly(tetramethylene oxide) glycol, a poly(hexamethylene glycol), a copolymer of ethylene oxide and propylene oxide, a copolymer of ethylene oxide glycol and tetrahydrofuran.

[0056] Aliphatic polyester can be poly(s-caprolactone), polyenanthractone, polycaprolactone, polybutylene adipate, polyethylene adipate.

[0057] The thermoplastic polyester elastomer can be modified with an unsaturated carboxylic acid, such as acrylic acid, maleic acid, fumaric acid, or their derivatives. In a preferred embodiment, the soft segment of the thermoplastic polyester elastomer comprises an aliphatic polyether selected from poly(tetramethylene oxide) glycol or poly(hexamethylene glycol).

[0058] The hard segment content in the thermoplastic polyester elastomer of the barrier layer can range from 10% by weight to 60% by weight, preferably from 20% by weight to 40% by weight compared to 100% by weight of thermoplastic polyester elastomer.

[0059] The soft segment content in the thermoplastic polyester elastomer of the barrier layer can range from 30% to 90% by weight, preferably from 50% to 80% by weight compared to 100% by weight of thermoplastic polyester elastomer.

[0060] Preferably, the thermoplastic polyester elastomer is a thermoplastic polyester-polyether.

[0061] The melting temperature of the thermoplastic polyester elastomer of the barrier layer can be greater than or equal to 90°C, preferably greater than or equal to 150°C, and even more preferably greater than or equal to 180°C.

[0062] The melting temperature of the thermoplastic polyester elastomer of the barrier layer may be less than or equal to 250°C, preferably less than or equal to 220°C.

[0063] The melting temperature can be determined by DSC (scanning calorimeter).

[0064] Thermoplastic polyester elastomer can have a Shore D hardness ranging from 30 to 80, preferably from 40 to 70, and even more preferably from 40 to 60. Shore D hardness can be measured as described in DIN ISO 7619-1.

[0065] The barrier layer may comprise one or more thermoplastic polyester elastomers as described above.

[0066] There are thermoplastic polyester elastomers marketed, for example, by Toray DuPont under the "Hytrel™" series or the "Arnitel™" series marketed by DSM. Notable examples include DSM's Arnitel EL630 (poly(ether-ester) copolymers) and DuPont's HYTREL® 6356.

[0067] The barrier layer may include at least one additive selected from the group consisting of pigments, fillers, dispersants, dyes, flame retardants, antioxidants, stabilizers, and mixtures thereof.

[0068] The total content of additives may range from 0% to 5%, preferably from 0.01% to 5%, and even more preferably from 0.01% to 2% by weight relative to the total weight of said barrier layer.

[0069] The barrier layer may comprise one or more non-elastomeric polymers, such as, for example, a polyolefin resin, a polystyrene resin, an ethylene-vinyl acetate copolymer.

[0070] Preferably, the barrier layer comprises more than 95% by weight of thermoplastic polyester elastomer as defined above, preferably more than 98% by weight, and even more advantageously more than 99% by weight, and even more preferably more than 99.9% by weight relative to the total weight of said barrier layer.

[0071] Preferably, the barrier layer does not include any polymers other than the thermoplastic polyester elastomer as defined above.

[0072] The barrier layer can have a total thickness ranging from 5 to 40 n, preferably from 5 to 30 pm, and even more preferably from 10 to 25 prn.

[0073] In one embodiment, the melting temperature of the barrier layer is higher than the melting temperature of the adhesive layer. This advantageously allows the adhesive layer to adhere to a substrate by heating it to a temperature lower than the melting temperature of the barrier layer. Thus, the adhesive layer is melted or softened sufficiently to adhere to the substrate while preventing the barrier layer from softening or melting, thereby preserving its properties.

[0074] Intermediate layer C

[0075] The intermediate layer C comprises at least one styrenic block copolymer.

[0076] Preferably, layer C is an intermediate layer, linked on one side to layer A and on the other side to layer B.

[0077] A styrene block copolymer is a copolymer comprising at least one styrene block, including in particular styrene triblock copolymers, styrene diblock copolymers, and mixtures thereof.

[0078] This styrene block copolymer has at least one block A that includes styrene and at least one block B that includes, for example, elastomeric conjugated dienes (e.g., hydrogenated and non-hydrogenated conjugated dienes), sesquiterpenes (e.g., hydrogenated and non-hydrogenated sesquiterpenes), and combinations thereof. Blocks A and B are linked to each other in various ways, allowing the resulting copolymer to adopt diverse structures, such as random, linear, branched, radial, star, comb, tapered, and combinations thereof.

[0079] The block copolymer can take various forms, including for example a linear block AB, a linear block ABA, a linear multiblock A-(BA)nB, where n is an integer of at least 3, a radial block (AB)nY, where Y is a multivalent compound and n is an integer of at least 3, a tetrablock copolymer, for example, ABAB, and a pentablock copolymer having an ABABA structure.

[0080] Examples of suitable styrene A blocks include styrene, alpha-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 2,4-dimethylstyrene, and 2,4,6-trimethylstyrene, as well as their combinations. Examples of suitable conjugated diene elastomeric B blocks include butadiene (e.g., polybutadiene), isoprene (e.g., polyisoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, as well as their hydrogenated versions, such as ethylene, propylene, and butylene, and their combinations.

[0081] The styrenic block copolymer is preferably chosen from the group consisting of SB, SI, SEB, SEP, SBBS, SBS, SEBS, SEPS, SEEPS, SIBS, SIS, and mixtures thereof.

[0082] "SBBS" refers to a styrene-butadiene-butylene-styrene triblock copolymer. "SBS" refers to a styrene-butadiene-styrene triblock copolymer. "SEBS" refers to a styrene-ethylene-butylene-styrene triblock copolymer. "SEPS" refers to a styrene-ethylene-propylene-styrene triblock copolymer. "SEEPS" refers to a styrene-ethylene-ethylene-propylene-styrene triblock copolymer. "S / BS" refers to a styrene-isoprene-butadiene-styrene triblock copolymer. "S / S" refers to a styrene-isoprene-styrene triblock copolymer. "SB" refers to a styrene-butadiene diblock copolymer. "S / " refers to a styrene-isoprene diblock copolymer. “SEB” refers to a styrene-ethylene-butylene diblock copolymer. “SEP’” refers to a styrene-ethylene-propylene diblock copolymer.

[0083] There are many commercially available styrenic block copolymers, such as KRATON D and G ® from Kraton Polymers, EUROPRENE Sol T ® from Versalis (Eni group), SOLPRENE ® from Dynasol Elastomers, SINOPEC ® from SINOPEC, or the Cawiton® range from Wittenburg.

[0084] Preferably, the styrenic block copolymer is chosen from SEBS, SEB, and their mixtures.

[0085] The intermediate layer C can have a total thickness ranging from 1 to 15 prn, preferably from 5 to 10 n.

[0086] Multilayer film

[0087] The multilayer film according to the invention comprises a barrier layer B and an adhesive layer A as defined above, and an intermediate layer C.

[0088] The aforementioned adhesive layer A may comprise one or more adhesive layers of the same or different natures.

[0089] The aforementioned barrier layer B may comprise one or more barrier layers of the same or different natures.

[0090] According to a preferred mode, the multilayer film comprises a single barrier layer B and a single adhesive layer A.

[0091] The total thickness of the multilayer film can range from 6 to 80 nm, preferably from 10 to 70 nm. The present invention also relates to a method for preparing a multilayer film as described above. The method may include a co-extrusion step, such as, for example, co-extrusion blow molding or flat die co-extrusion.

[0092] As is known to those skilled in the art, the coextrusion-inflation process comprises: the melting, in separate extruders, of the constituent compositions of the adhesive and barrier layers; then the passage of the corresponding flows through an annular and concentric die, so as to form a multi-layered tubular bubble, then the radial expansion (relative to the annular die) and the stretching (in the axial direction) of the bubble; then the cooling of the bubble.

[0093] The geometric characteristics of the dies, as well as process parameters such as radial expansion rate and stretching speed, can be fixed to obtain the desired thickness for the different constituent layers of the multilayer film.

[0094] Laminates / uses

[0095] The present invention also relates to the use of the multilayer film as defined above for the preparation of laminate.

[0096] The present invention relates to the preparation of a laminate comprising: the supply of a multilayer film as defined above; the bonding of the multilayer film onto a substrate.

[0097] The bonding step can be carried out by laminating the film onto the substrate and heating to a temperature below the melting temperature of the barrier layer (e.g. after or during deposition on substrate).

[0098] The adhesive layer is in particular the layer of the multilayer film which is in contact with the substrate to which it adheres, which advantageously allows the barrier layer of the multilayer film to adhere to the substrate.

[0099] The substrate can be of various types. It can be a substrate chosen from foams, textiles, plastics, metals, elastomers, thermosets, composites.

[0100] Textiles can be made from synthetic fibers, natural fibers, semi-synthetic fibers, inorganic fibers, or mixtures thereof.

[0101] Examples of synthetic fibers include polyamide-based copolymers (such as nylon), polyesters (such as polybutylene terephthalate PBT, polyethylene terephthalate PET), polyether ketones, and / or polyolefins.

[0102] The multilayer film is preferably intended for application to textiles. More specifically, the multilayer film is intended to be applied to textiles via its adhesive layer.

[0103] The present invention relates to the use of multilayer film, or laminate, as defined above for the bonding / preparation of parts, for example parts found in automobiles.

[0104] The pieces thus formed can be used for soundproofing in the automotive field (such as for example in the engine hood, the trunk floor, floor mats, ...), for safety, for decoration.

[0105] All the embodiments described above can be combined with each other.

[0106] In the context of the invention, "between x and y" or "ranging from x to y" means an interval in which the bounds x and y are included. For example, the range "between 0% and 25%" includes, in particular, the values ​​0% and 25%.

[0107] The invention is now described in the following embodiment examples which are given for illustrative purposes only, and should not be interpreted to limit its scope.

[0108] Example 1: Preparation of the multilayer film (Film F1) by coextrusion qonflaae

[0109] Composition A is used as the constituent of the adhesive layer: a linear low-density polyethylene (LLDPE) modified with maleic anhydride (content less than 0.2%), having an MFR equal to 3 g / 10 min (190°C, / 2.16 kg).

[0110] The composition B used to constitute the barrier layer is a thermoplastic copolyester elastomer: Melting range (ISO 11357-1 and -3): 207°C, Shore D hardness (ISO 868, 3s): 53, Melt flow index by mass MFR (ISO 1133): 9.68 g / min (230°C; 21.6kg).

[0111] The intermediate layer, composition C, is a thermoplastic elastomer compound comprising a SEBS. The F1 film is manufactured on a blown coextrusion line with at least 3 screw extruders.

[0112] The process parameters are adjusted to produce a three-layer film comprising: an adhesive layer with a thickness of 32 pm made up of composition A; an intermediate layer with a thickness of 8 pm made up of composition C; a barrier layer with a thickness of 20 n made up of composition B.

[0113] Among the parameters that are usually set, we can mention:

[0114] Extruder temperatures of the adhesive layer between 170 and 210°C, Extruder temperatures of the barrier layer between 210 and 250°C, Die temperatures between 210 and 250°C

[0115] The inflation ratio (BUR: Blow Up Ratio) used is between 1.2 and 3.

[0116] The three-layer film thus obtained has a total thickness of 60 prn.

[0117] Example 2: Properties of the F1 film

[0118] Peel tests according to ISO 11339 (test speed 100 mm / min, load cell 1 kN) were carried out on bonded assemblies of polyester textile / F1 film (example 1) / TPU-coated textile

[0119] Peel tests allow us to measure the adhesion strength of films on polyester textiles.

[0120] Assembly :

[0121] Preparation for assembly: The textile and film were cut into dimensions of 50x250mm (in the directions of the extrusion and weaving machine).

[0122] A platen press was powered on and the following settings were made:

[0123] Temperature of the upper and lower trays: 180°C

[0124] Press pressure set at 4 bars

[0125] Bonding time: 30s.

[0126] Once bonded, the assembly was cooled to 23°C and subjected to a peel test after 24 hours (initial peel). The results are given in the following table:

[0127] The F1 film advantageously exhibits an initial peel force of 0.84 N / mm, without exhibiting delamination.

Claims

DEMANDS 1. Multilayer film comprising: an adhesive layer A comprising at least one polyolefin modified by a carboxylic acid and / or by one of its derivatives; an intermediate layer C comprising at least one styrenic block copolymer; a barrier layer B comprising at least one thermoplastic polyester elastomer.

2. Film according to claim 1, characterized in that the content of carboxylic acid and / or one of its derivatives of the modified polyolefin ranges from 0.1% to 2.0% by weight relative to the total weight of said modified polyolefin.

3. Film according to claim 1 or claim 2, characterized in that the carboxylic acid is selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, and mixtures thereof.

4. Film according to any one of claims 1 to 3, characterized in that the carboxylic acid derivatives are selected from maleic anhydride, itaconic anhydride, dimethyl maleic anhydride.

5. Film according to any one of claims 1 to 4, characterized in that the adhesive layer A comprises at least one polyolefin modified (preferably grafted) by maleic acid or maleic anhydride.

6. Film according to claim 5, characterized in that the total content of maleic acid or maleic anhydride in the modified polyolefin ranges from 0.1% to 2% by weight relative to the total weight of said modified polyolefin.

7. Film according to any one of claims 1 to 6, characterized in that the polyolefin is a homopolymer of C2-C20 alpha-olefins, preferably the polyolefin is selected from polyethylenes, polypropylenes, polybutylenes, and mixtures thereof.

8. Film according to any one of claims 1 to 7, characterized in that the adhesive layer A comprises a modified polyethylene (preferably grafted) by maleic anhydride.

9. Film according to any one of claims 1 to 8, characterized in that the thermoplastic polyester elastomer is of the polyester-polyester type (having in particular the soft segment comprising a polyester) or polyester-polyether type (having in particular the soft segment comprising a polyether) or polyester-polyester / polyether type (having in particular the soft segment comprising a polyester-polyether copolymer), preferably a thermoplastic polyester-polyether.

10. Film according to any one of claims 1 to 9, characterized in that the thermoplastic polyester elastomer has a Shore D hardness ranging from 30 to 80, preferably from 40 to 70, and even more preferably from 40 to 60.

11. Film according to any one of claims 1 to 10, characterized in that the barrier layer comprises more than 95% by weight of thermoplastic polyester elastomer, preferably more than 98% by weight, and even more advantageously more than 99% by weight, and even more preferably more than 99.9% by weight relative to the total weight of said barrier layer.

12. Film according to any one of claims 1 to 11, characterized in that the styrenic block copolymer is selected from the group consisting of SB, SI, SEB, SEP, SBBS, SBS, SEBS, SEPS, SEEPS, SIBS, SIS, and mixtures thereof.

13. Film according to any one of claims 1 to 12, characterized in that the styrenic block copolymer is selected from SEBS, SEB, and mixtures thereof.

14. Laminate comprising the multilayer film according to any one of claims 1 to 13.

15. Use of the multilayer film according to any one of claims 1 to 13, or of the laminate according to claim 14, for the bonding / preparation of parts, for example of parts found in automobiles.

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