Plastomeric toughened / rigidified polyolefin multilayer films and laminates containing same

Abstract

The present disclosure provides a multilayer film having a sealant layer and a first layer, the first layer being formed from a first polyolefin composition, as well as a laminate comprising the multilayer film. The first polyolefin composition of the first layer consists essentially of a high-density polyethylene (HDPE) resin and a propylene-ethylene copolymer thermoplastic elastomer (TPE). In addition to the first layer of the first polyolefin composition and the sealant layer, the laminate also includes a substrate film and an adhesive layer in adhesive contact with the substrate film and the first layer, the adhesive layer comprising a polyurethane, the polyurethane having a modulus of elasticity, measured according to ASTM D412, of greater than 25 MPa when the adhesive layer is formed from a solventless adhesive, and greater than 0.30 MPa when the adhesive layer is formed from a solvent-based adhesive.

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE This disclosure relates generally to polyolefin multilayer films, and more specifically to plastomer-toughened / stiffened polyolefin multilayer films, and laminates including such multilayer films. [Background technology]

[0002] Typical toughened polyolefin films used in stand-alone pouch (SUP) multilayer films or laminates are made of linear low density polyethylene (LLDPE), metallocene-catalyzed LLDPE (m-LLDPE), and high density polyethylene (HDPE) blends, where the films can have thicknesses of 50-150 μm, with each individual coextruded layer being a fraction of the total thickness. The combination of such systems aims for a final multilayer film / laminate structure that combines high stiffness and high toughness.

[0003] Further improvement and thinning of polyolefin films used in multilayer films and / or laminates requires that these films meet the conflicting objective that as the film becomes thinner it must be stiffer to compensate for the loss of bending stiffness due to the reduction in thickness. However, previous approaches to improving stiffness also reduced the toughness and fast deformation resistance of the film. This toughness is the second conflicting property that thinner films must still possess. Film toughness (as seen in dart, puncture, and tear tests) is improved by selecting lower density polyethylene resins such as ultralinear low density polyethylene (ULLDPE) or m-LLDPE, which typically reduces the stiffness of the film. Thus, improvements are needed toward balancing stiffness and toughness in coextruded polyolefin films intended for multilayer film and / or laminate structures. Summary of the Invention

[0004] The present disclosure provides a multilayer film having a first layer and a sealant layer, and a laminate comprising the multilayer film. The multilayer film of the present disclosure helps achieve high stiffness and high toughness of the laminate due in part to the first layer formed from the first polyolefin composition. As discussed herein, the balance of stiffness and toughness provided by the first layer is also surprisingly improved compared to the use of other elastomers. One main application of the laminate with the multilayer film is a self-supporting pouch that requires an improved balance of stiffness and toughness. The laminate with the multilayer film can also be useful in other types of applications, such as heavy-duty shipping bags.

[0005] In various embodiments, the multilayer film of the present disclosure includes a first layer formed from a first polyolefin composition and a sealant layer on the first layer. The first polyolefin composition of the present disclosure consists essentially of a high density polyethylene (HDPE) resin and a propylene-ethylene copolymer thermoplastic elastomer (TPE). Specifically, the first layer comprises: (a) 80 to 99.9 weight percent (wt%) of the first polyolefin composition based on the total weight of the first polyolefin composition, the sealant layer having a viscosity of 0.935 to 0.966 g / cm, as measured according to ASTM D792; 3 and a melt index (I2) of 0.3 to 8 g / 10 min as measured at 190° C. / 2.16 kg according to ASTM D-1238, and (b) 0.1 to 20 wt. % of a polyolefin composition having at least 60 wt. % of units derived from propylene and at least 0.1 wt. % of units derived from ethylene, the polyolefin composition comprising at least one HDPE resin having a density of 0.850 to 0.900 g / cm as measured according to ASTM D792. 3and a melt index I2 of 0.1 to 15 g / 10 min as measured at 230° C. / 2.16 kg according to ASTM D-1238. In additional embodiments, the first polyolefin composition can have 90 to 98 wt. % HDPE resin and 2 to 10 wt. % propylene-ethylene copolymer TPE. In various embodiments, the first layer has a thickness of 30 to 150 micrometers (μm). In various embodiments, the propylene-ethylene copolymer TPE has a melting temperature of 50 to 130° C. as taken at the differential scanning calorimeter (DSC) Tm peak. Additionally, the propylene-ethylene copolymer TPE has a flexural modulus of 20 to 60 megapascals (MPa) as measured according to ASTM D790.

[0006] In various embodiments, the sealant layer has a viscosity of 0.880 to 0.915 g / cm, which is 50 to 100 percent by weight of the sealant layer. 3 and a melt index I2 of 0.5 to 5 g / 10 min measured at 190° C. / 2.16 kg according to ASTM D-1238, and a peak melting point in the range of 85° C. to 105° C., and a molecular weight distribution Mw / Mn in the range of 2.0 to 3.0.

[0007] The laminate of the present disclosure comprises (i) a substrate film, (ii) a multilayer film as provided herein, and (iii) an adhesive layer comprising a polyurethane, the adhesive layer being in adhesive contact with the substrate film and the first layer (first polyolefin composition) of the multilayer film as provided herein. In various embodiments, the substrate film comprises a biaxially oriented polyethylene terephthalate film, a biaxially oriented polypropylene film, or an oriented polyethylene film. In various embodiments, the first layer is as provided above and herein. In various embodiments, the sealant layer in contact with the first layer may be formed from a polyethylene as provided herein. In various embodiments, the adhesive layer comprising a polyurethane in adhesive contact with the substrate film and the first layer has a modulus of elasticity of the polyurethane measured according to ASTM D412, when the adhesive layer is formed from a solventless adhesive, the adhesive layer has a modulus of elasticity of more than 25 MPa, and when the adhesive layer is formed from a solvent-based adhesive, the adhesive layer has a modulus of elasticity of more than 0.30 MPa.

[0008] Laminate embodiments of the present disclosure further include those in which the substrate film is a biaxially oriented polyethylene terephthalate film having a thickness of 8 to 20 μm. Laminate embodiments of the present disclosure further include those in which the substrate film is a biaxially oriented polypropylene film having a thickness of 15 to 50 μm. Laminate embodiments of the present disclosure further include those in which the substrate film is a biaxially oriented polyethylene film or a uniaxially oriented polyethylene film having a thickness of 15 to 50 μm. Laminate embodiments of the present disclosure further include those in which the propylene-ethylene copolymer TPE has a melting temperature of 50 to 130° C. as taken at the DSC Tm peak.

[0009] Laminate embodiments of the present disclosure further include those in which the propylene-ethylene copolymer TPE has a flexural modulus of 20 to 60 megapascals (MPa) as measured according to ASTM D790. Laminate embodiments of the present disclosure further include those in which the first polyolefin composition has 90 wt% HDPE resin and 10 wt% propylene-ethylene copolymer TPE. Laminate embodiments of the present disclosure further include those in which the first layer has a thickness of 30 to 150 μm. Laminate embodiments of the present disclosure further include those in which the adhesive layer has a thickness of 1 to 5 μm. Laminate embodiments of the present disclosure further include those in which the first polyolefin composition comprises 5 to 15 wt% propylene-ethylene copolymer TPE. In various embodiments, the sealant layer may be formed from polyethylene as described herein.

[0010] The present disclosure also provides a package comprising the laminate provided herein.For example, in one embodiment, the package comprising the laminate is a self-supporting pouch.The present disclosure also provides a method for making the laminate provided herein, comprising forming a film from a first polyolefin composition by one or more of the following processes: film blowing and film casting. [Brief description of the drawings]

[0011] [Figure 1] 1 provides machine direction stress / strain data for single films of examples and comparative examples of the present disclosure. [Diagram 2] 1 provides the toughness / stiffness balance of mono- and coextruded films of examples and comparative examples of the present disclosure. [Diagram 3] 1 provides the critical drop heights of laminates using solvent-based and solventless rigid and flexible adhesives of examples and comparative examples of the present disclosure. [Figure 4] 1 provides tensile properties of laminates made with PET / coextruded film using several adhesives of the examples and comparative examples of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present disclosure provides a multilayer film having a first layer and a sealant layer, and a laminate comprising the multilayer film. The multilayer film of the present disclosure can help achieve high stiffness and high toughness of the laminate due in part to the first layer formed from the first polyolefin composition. As discussed herein, the balance of stiffness and toughness provided by the first layer is also surprisingly improved compared to the use of other elastomers. One main application of the laminate with the multilayer film is a self-supporting pouch that requires an improved balance of stiffness and toughness. The laminate with the multilayer film can also be useful for other types of applications, such as heavy-duty shipping bags.

[0013] In various embodiments, the multilayer film of the present disclosure includes a first layer formed from a first polyolefin composition and a sealant layer on the first layer. The first polyolefin composition of the present disclosure consists essentially of a high density polyethylene (HDPE) resin and a propylene-ethylene copolymer thermoplastic elastomer (TPE). Specifically, the first layer comprises: (a) 80 to 99.9 weight percent (wt%) of the first polyolefin composition based on the total weight of the first polyolefin composition, the sealant layer having a viscosity of 0.935 to 0.966 g / cm, as measured according to ASTM D792; 3 and a melt index (I2) of 0.3 to 8 g / 10 min as measured at 190° C. / 2.16 kg according to ASTM D-1238, and (b) 0.1 to 20 wt. % of a polyolefin composition having at least 60 wt. % of units derived from propylene and at least 0.1 wt. % of units derived from ethylene, the polyolefin composition comprising at least one HDPE resin having a density of 0.850 to 0.900 g / cm as measured according to ASTM D792. 3 and a melt index I2 of 0.1 to 15 g / 10 min as measured at 230° C. / 2.16 kg according to ASTM D-1238.

[0014] In various embodiments, the sealant layer of the multilayer film may comprise a polyethylene or a blend of polyethylenes. In some embodiments, the sealant layer of the multilayer film may comprise 50 to 100 percent by weight of 0.880 to 0.915 g / cm 3 The sealant layer comprises a polyethylene having a density of 0.5 to 5 g / 10 min measured at 190° C. / 2.16 kg according to ASTM D-1238, a peak melting point in the range of 85° C. to 105° C. as taken by DSC Tm peak, and a molecular weight distribution Mw / Mn in the range of 2.0 to 3.0. In some embodiments, the sealant layer comprises a blend of linear low density polyethylene and polyolefin plastomer. However, it is understood that the sealant layer may include only a single polyolefin component for the sealant layer (e.g., the sealant layer is formed from 100 percent by weight linear low density polyethylene or 100 percent by weight polyolefin plastomer).

[0015] As used herein, "consisting essentially of" or "consisting essentially of" is intended to limit the scope of the present disclosure to the specific materials of the first polyolefin composition provided herein and those that do not substantially affect the basic characteristics of the first polyolefin composition used in the first layer of the present disclosure. As provided herein, the basic and novel characteristics are provided in the HDPE Resin section of the disclosure below.

[0016] As used herein, the term "composition" includes mixtures of materials, including compositions and reaction products and decomposition products formed from the materials of the composition.

[0017] As used herein, the term "multilayer film" refers to a sheet, web, or the like, or combination thereof, having two major surfaces having dimensions of length and width and a thickness therebetween. A multilayer film has two or more layers bonded together by one or more of the following methods: coextrusion, extrusion coating, vapor deposition coating, solvent coating, emulsion coating, or suspension coating.

[0018] As used herein, the term "laminate" refers to a combination of two or more individually formed films and / or multi-layer films that are then bonded together, for example with an adhesive.

[0019] As used herein, the term "polymer" refers to a polymeric compound prepared by polymerizing monomers, whether of the same or different types. Thus, the generic term polymer encompasses the term "homopolymer," which is commonly used to refer to a polymer prepared from only one type of monomer, as well as the term "copolymer," which refers to a polymer prepared from two or more different types of monomers.

[0020] "Polyethylene" shall mean a polymer containing more than 50% by weight of units derived from ethylene monomer. This includes polyethylene homopolymers or copolymers (meaning that the units are derived from two or more comonomers). Common forms of polyethylene known in the art include low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ultra low density polyethylene (ULDPE), very low density polyethylene (VLDPE), single-site catalyzed linear low density polyethylene (m-LLDPE), which includes both linear and substantially linear low density resins, and high density polyethylene (HDPE). These polyethylene materials are generally known in the art, but the following explanation may be useful in understanding the differences between some of these different polyethylene resins.

[0021] The term "LDPE" may also be referred to as "high pressure ethylene polymer", or "highly branched polyethylene", and is defined to mean that the polymer is partially or fully homopolymerized or copolymerized in an autoclave or tubular reactor at pressures above 14,500 psi (100 MPa) using a free radical initiator such as peroxide (see, for example, US 4,599,392, incorporated herein by reference). LDPE resins typically have a viscosity of 0.916 to 0.940 g / cm. 3 It has a density in the range of

[0022] As used herein, the term "polyolefin plastomer" refers to a polymeric material having qualities of both an elastomer and a plastic. Examples of such polyolefin plastomers include those having a viscosity of 0.870 to 0.905 g / cm 3 and melting points (determined using DSC, DOW method) between 55° C. and 108° C.

[0023] The term "LLDPE" includes both resins made using conventional Ziegler-Natta catalyst systems as well as resins made using single-site catalysts such as metallocenes (sometimes referred to as "m-LLDPE") and includes linear, substantially linear or heterogeneous polyethylene copolymers or homopolymers. LLDPEs contain shorter chain branches than LDPEs and include substantially linear ethylene polymers as further defined in U.S. Pat. Nos. 5,272,236, 5,278,272, 5,582,923, and 5,733,155, homogeneously branched linear ethylene polymer compositions such as those in U.S. Pat. No. 3,645,992, heterogeneously branched ethylene polymers such as those prepared according to the process disclosed in U.S. Pat. No. 4,076,698, and / or blends thereof (such as those disclosed in U.S. Pat. No. 3,914,342 or U.S. Pat. No. 5,854,045). Linear PE can be made via gas phase, solution phase, or slurry polymerization, or any combination thereof, using any type of reactor or reactor configuration known in the art, with gas phase and slurry phase reactors being most preferred.

[0024] The term "HDPE" means approximately 0.940 g / cm 3 It refers to polyethylene having a density greater than 1000 nm and is generally prepared with Ziegler-Natta, chromium, or even metallocene catalysts.

[0025] In the present invention, the following analytical methods are used: "Density" is determined in accordance with ASTM D792.

[0026] "Melt index," also referred to as "I2," is determined in accordance with ASTM D-1238 (measured at either 230° C., 2.16 kg, or 190° C., 2.16 kg, as provided herein).

[0027] The peak melting point is determined by differential scanning calorimetry (DSC) by conditioning a film (0.1-0.2 mil thick, 3-10 mg, 6 mm diameter sample) at 180°C for 5 minutes and then cooling to a temperature of -40°C at a rate of 10°C per minute. After holding the film at -40°C for 5 minutes, the film is heated to 200°C at a rate of 10°C per minute.

[0028] The term molecular weight distribution or "MWD" is defined as the ratio of weight average molecular weight to number average molecular weight (Mw / Mn) - Mw and Mn are determined according to methods known in the art using conventional gel permeation chromatography (conventional GPC).

[0029] First layer HDPE resin The HDPE resin of the first layer has a hardness of 0.935 to 0.966 g / cm3 as measured in accordance with ASTM D792. 3 and a melt index (I2) of 0.3 to 8 g / 10 min as measured at 190° C. / 2.16 kg according to ASTM D-1238. In various embodiments, the HDPE resin may have additional density and I2 values. For example, the HDPE resin of the first layer may have a melt index of 0.945 to 0.966 g / cm as measured according to ASTM D792. 3 and an I2 of 0.3 to 2 g / 10 min as measured at 190° C. / 2.16 kg according to ASTM D-1238. Preferably, the HDPE resin has a density of 0.955 to 0.966 g / cm3 as measured according to ASTM D792. 3 and an I2 of 0.4 to 1 g / 10 min as measured according to ASTM D-1238 at 190° C. / 2.16 kg. In some embodiments, the HDPE resin has a density of 0.955 to 0.966 g / cm as measured according to ASTM D792. 3 and an I2 of 0.5 to 1 g / 10 min as measured according to ASTM D-1238 at 190° C. / 2.16 kg. In some embodiments, the HDPE resin has a density of 0.962 to 0.966 g / cm as measured according to ASTM D792. 3 and an I2 of 0.8 to 0.9 g / 10 min measured at 190°C / 2.16 kg in accordance with ASTM D-1238.

[0030] In various embodiments, the HDPE resin also has a modulus of elasticity between 500 and 2000 MPa, the modulus being measured according to ASTM D882-18. The modulus of elasticity as tested under ASTM D882-18 provides an indication of the stiffness of a thin sheet (e.g., 0.1 mm to 0.25 mm) of the HDPE resin, and the toughness of the HDPE resin can be considered as the total energy absorbed up to the point of rupture per unit volume of a thin sheet of the HDPE resin. In some embodiments, the HDPE resin has a modulus of elasticity between 700 and 1500 MPa, the modulus being measured according to ASTM D882-18. In some embodiments, the HDPE resin has a modulus of elasticity between 1000 and 1200 MPa, the modulus being measured according to ASTM D882-18.

[0031] The HDPE resins of the present disclosure may have a unimodal molecular weight distribution or a bimodal weight distribution. In various embodiments, the HDPE resins of the present disclosure may be formed via gas phase, solution phase, or slurry polymerization, or combinations thereof, using reactors or reactor configurations known in the art. The HDPE may be formed as substantially linear ethylene polymers, homogeneously branched linear ethylene polymers, heterogeneously branched ethylene polymers, and / or blends thereof.

[0032] Commercial examples of HDPE resins include those sold under the trademark ELITE™ available from The Dow Chemical Company. Specific examples of ELITE™ HDPE resins include, among others, ELITE™ 5960G.

[0033] First layer: propylene-ethylene copolymer thermoplastic elastomer (TPE) The propylene-ethylene copolymer thermoplastic elastomer (TPE) of the present disclosure is a non-functionalized propylene-ethylene copolymer, which may include a propylene-ethylene alternating copolymer. The TPE contains at least two segments, one of which is thermoplastic and the other of which is elastomeric, which serves to provide the propylene-ethylene copolymer TPE with the properties of an elastomer that allows it to be stretched beyond its original length, and also the ability to shrink back to substantially its original length when released. The propylene-ethylene copolymer thermoplastic elastomer TPE can also be processed like a thermoplastic, with the ability to soften when exposed to heat and return to substantially its original state when cooled to room temperature.

[0034] As discussed herein, the first polyolefin composition of the present disclosure is formulated with a propylene-ethylene copolymer TPE resin that enhances the overall toughness and stiffness balance properties of a multilayer film formed with the composition. The propylene-ethylene copolymer TPE comprises 0.1-20 wt% of the first polyolefin composition. In some embodiments, the propylene-ethylene copolymer TPE comprises 5-15 wt% of the first polyolefin composition. In some embodiments, the propylene-ethylene copolymer TPE comprises 5-10 wt% of the first polyolefin composition.

[0035] In various embodiments, the propylene-ethylene copolymer TPE resin comprises at least 60% by weight of units derived from propylene and at least 0.1% by weight of units derived from ethylene. For example, the propylene-ethylene copolymer TPE resin may comprise 60% to 99.9% by weight of units derived from propylene and 40% to 0.1% by weight of units derived from ethylene. All individual values ​​and subranges of 60% to 99.9% by weight of units derived from propylene and 40% to 0.1% by weight of units derived from ethylene are included and disclosed herein. For example, the propylene-derived units of the propylene-ethylene copolymer TPE resin may be from a lower limit of 60, 65, 70, or 75% by weight to an upper limit of 80, 85, 90, 95, or 99.9% by weight, while the ethylene-derived units of the propylene-ethylene copolymer TPE resin may be from a lower limit of 0.1, 5, 10, 15, or 20% by weight to an upper limit of 25, 30, 35, or 40% by weight. Specific examples include propylene-ethylene copolymer TPE resins in the range of 60 to 99.9% by weight derived from propylene, and units derived from ethylene in the range of 0.1 to 40% by weight. Preferably, the propylene-ethylene copolymer TPE resins in the range of 65 to 95% by weight derived from propylene, and units derived from ethylene in the range of 5 to 35% by weight. More preferably, the propylene-ethylene copolymer TPE resins in the range of 65 to 95% by weight derived from propylene, and units derived from ethylene in the range of 5 to 35% by weight.

[0036] Propylene-ethylene copolymer TPE resins have a density of 0.850 to 0.900 g / cm3 as measured in accordance with ASTM D792. 3 and a melt index (I2) of 0.1 to 15 g / 10 min, measured at 230 °C / 2.16 kg according to ASTM D-1238. 3and melt index I2 from 0.1 to 15 g / 10 min as measured at 230° C. / 2.16 kg are provided herein. For example, propylene-ethylene copolymer TPE resins may have a density of 0.850, 0.855, or 0.860 g / cm3 as measured according to ASTM D792. 3 Lower limit ~ 0.865, 0.870, 0.875, 0.880, 0.885, or 0.900 g / cm3 measured according to ASTM D792 3 Specific examples include those having an upper density of 0.855 to 0.895 g / cm3 as measured according to ASTM D792. 3 , 0.860-0.885 g / cm3 measured according to ASTM D792 3 or 0.862 to 0.865 g / cm3 measured according to ASTM D792 3 The range of densities is included.

[0037] Propylene-ethylene copolymer TPE resins are heat treated according to ASTM D-1238 (230°C / 2.16Kg The TPE resins may have a melt index (I2), measured at 0.5 to 3 g / 10 min, in the range of 0.1 to 5 g / 10 min. All individual values ​​and subranges from 0.1 to 5 g / 10 min are included and disclosed herein, for example, I2 may have a lower limit of 0.1, 0.2, 0.5, 1.0, or 1.5 to an upper limit of 5, 4, 3, or 2.5 g / 10 min. For example, a propylene-ethylene copolymer TPE resin may have an I2 in the range of 0.5 to 3 g / 10 min, or alternatively 1.5 to 2.5 g / 10 min.

[0038] The propylene-ethylene copolymer TPE resin has a molecular weight distribution (MWD), defined as the weight average molecular weight divided by the number average molecular weight (Mw / Mn), less than or equal to 3.5, alternatively less than or equal to 3.0, or in another alternative, from 1.8 to 3.0.

[0039] The propylene-ethylene copolymer TPE resin may have a flexural modulus (1% secant) of 20 to 60 megapascals (MPa) as measured according to ASTM D790. All individual values ​​and subranges from 20 to 60 MPa are included and disclosed herein, for example, the flexural modulus may be from a lower limit of 20, 25, 30, or 35 to a lower limit of 60, 55, 50, or 45 MPa. For example, the propylene-ethylene copolymer TPE resin may have a flexural modulus in the range of 25 to 55 MPa, or alternatively 35 to 45 MPa.

[0040] Particularly desirable propylene-ethylene copolymer TPEs have melting temperatures between 50 and 130° C. as measured using differential scanning calorimetry (DSC) as known in the art, the melting temperature (Tm) being taken as the DSC peak. The melting temperature at the DSC peak is determined by differential scanning calorimetry (DSC) where a film (0.1-0.2 mil thick, 3-10 mg, 6 mm diameter sample) is conditioned at 180° C. for 5 minutes and then cooled at a rate of 10° C. per minute to a temperature of −40° C. After holding the film at −40° C. for 5 minutes, the film is heated to 200° C. at a rate of 10° C. per minute.

[0041] An example of such a non-functionalized propylene-ethylene copolymer includes, but is not limited to, VERSIFY™ DE-2400.05 available from The Dow Chemical Company.

[0042] Sealant Layer In various embodiments, a sealant layer refers to at least one of the external or outer layers of the multilayer films and / or laminates provided herein, where the sealant layer is involved in sealing the multilayer film or laminate to itself or to a package (e.g., a stand-alone pouch) for contacting and closing the package.

[0043] In various embodiments, the sealant layer of the multilayer film can include polyethylene or a blend of polyethylene. For example, in various embodiments, the sealant layer can include 50 to 100 weight percent, preferably at least 60, 70, 80, 90, or even 100 weight percent of a polyethylene having a viscosity of 0.880 to 0.915 g / cm. 3 Preferably, the sealant layer comprises a polyethylene having a density of 0.895 to 0.905 g / cm3, a melt index I2 of 0.5 to 5 g / 10 min, preferably 0.8 to 1.2 dg / min, more preferably 0.9 to 1.1 dg / min, measured at 190° C. / 2.16 kg according to ASTM D-1238, and a peak melting point in the range of 85° C. to 105° C., preferably 90° C. to 100° C., as taken by DSC Tm peak, and a molecular weight distribution, Mw / Mn, in the range of 2.0 to 3.0. In some embodiments, the sealant layer comprises a blend of linear low density polyethylene and a polyolefin plastomer. Preferably, when present, the polyolefin plastomer is preferably a polyethylene plastomer. However, it is understood that the sealant layer may comprise only a single polyethylene component for the sealant layer (e.g., the sealant layer is formed from 100 percent by weight linear low density polyethylene or 100 percent by weight polyolefin plastomer).

[0044] Preferably, the polyethylene or blend of polyethylene provides the sealant layer with a heat seal strength of at least 25 N / 25 mm, more preferably at least 30, even more preferably at least 35 N / 25 mm at 90° C. It is also preferred that the sealant layer has a thickness in the range of 5 to 15 microns, preferably in the range of 10 to 15 microns.

[0045] The sealant layer may also include other possible polyolefin compositions. Examples of these other polyolefin compositions include ethylene vinyl acetate (EVA) and ethylene methyl acrylate (EMA) copolymers, which are known to provide heat seal properties and can be made peelable by incorporating polybutylene or ionomers. Propylene-based elastomers or plastomers (such as the VERSIFY™ resin family available from Dow Chemical Company) have a range of seal strengths that make them well suited for use as the sealant layer of some embodiments, especially when mixed with a second polymer, preferably from the group consisting of polyethylene and styrene polymers. A layer of linear low density polyethylene (LLDPE) can also be used as the sealant layer, in which case the thickness of the sealant layer can be used to determine the peel force required to open the seal.

[0046] First Polyolefin Composition In various embodiments, the first polyolefin composition of the present disclosure consists essentially of (a) 80-99.9 weight percent (wt%) HDPE resin and (b) 0.1-20 wt% propylene-ethylene copolymer TPE, both of which are provided herein, with the wt% values ​​being based on the total weight of the first polyolefin composition. All individual values ​​and subranges of (a) 80-99.9 wt% HDPE resin and (b) 0.1-20 wt% propylene-ethylene copolymer TPE are included and disclosed herein. For example, preferably, the first polyolefin composition of the present disclosure consists essentially of (a) 90-98 wt% HDPE resin and (b) 2-10 wt% propylene-ethylene copolymer TPE, both of which are provided herein, with the wt% values ​​being based on the total weight of the first polyolefin composition. In one particular embodiment, the first polyolefin composition has 90% by weight HDPE resin and 10% by weight propylene-ethylene copolymer TPE.

[0047] As discussed above, the first polyolefin composition of the present disclosure consists essentially of (a) HDPE resin and (b) propylene-ethylene copolymer TPE, both of which are provided herein. "Consisting essentially of" or "consisting essentially of" limits the scope of the present disclosure to the specific materials of the first polyolefin composition provided herein and those that do not substantially affect the basic characteristics of the first polyolefin composition used in the first layer of the present disclosure. Other components that can be added to the first polyolefin composition of the present disclosure that do not substantially affect the basic characteristics of the first polyolefin composition used in the first layer of the present disclosure include additives known in the art, such as inorganic fillers, conductive fillers, pigments, nucleating agents, clarifiers, antioxidants, acid scavengers, oxygen scavengers, flame retardants, UV absorbers, processing aids such as zinc stearate, extrusion aids, slip additives, permeability modifiers, antistatic agents, antiblocking additives, and combinations thereof. Such additives may be present in typical amounts of up to 10 weight percent of the first polyolefin composition.

[0048] As discussed herein, the multilayer film of the present disclosure includes two or more layers bonded together by one or more of the following methods: coextrusion, extrusion coating, vapor deposition coating, solvent coating, emulsion coating, or suspension coating. The multilayer film of the present disclosure includes a first layer formed from a first polyolefin composition and a sealant layer on the first layer. In various embodiments, the multilayer film may include two or more (e.g., two or more) of each of the first layer and the sealant layer. For example, the sealant layer may be the first outer layer of the multilayer film, the first of the first layer may be the second outer layer, and the second of the first layer may be a core layer between the first outer layer and the second outer layer of the multilayer film. In such embodiments, the first polyolefin composition of the first of the first layer and the second of the first layer may be the same or different depending on the intended purpose of the multilayer film. In additional embodiments, the multilayer film may include one or more of the first layer, the sealant layer, and the additional layer, where the sealant layer and the first layer provide the outer layer of the multilayer film, and the additional layer provides one or more core phases. In such embodiments, the additional layer may be a polyolefin that is compositionally different from either the first polyolefin composition of the first layer(s) and the first polyolefin composition of the sealant layer. In additional embodiments, the multilayer film may include one or more of the first layer, the sealant layer, and the additional layer, where the sealant layer and the additional layer provide the outer layer of the multilayer film, and the first layer provides one or more core phases. In such embodiments, the additional layer may be a polyolefin that is compositionally different from either the first polyolefin composition of the first layer(s) and the first polyolefin composition of the sealant layer. Advantageously, the additional layer(s) may comprise a polymeric material selected from the group consisting of propylene-based plastomers or elastomers, propylene homopolymers, medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), ethylene-based plastomers or elastomers, or blends thereof.Such additional layers, if present, may be selected to provide additional functionality as is generally known in the art.

[0049] The multilayer films of the present disclosure may have a total thickness ranging from 10 μm to 400 μm, with all individual values ​​and subranges from 50 μm to 400 μm being included herein and disclosed herein, for example, the total thickness may have a lower limit of 50, 60, 70, or 80 μm to an upper limit of 200, 300, 350, or 400 μm. For example, the multilayer film may be from 60 μm to 350 μm, or alternatively from 70 μm to 300 μm, or alternatively from 80 μm to 200 μm.

[0050] As discussed herein, the first layer formed from the first polyolefin composition has a thickness of 30 to 150 micrometers (μm). In various embodiments, the first layer formed from the first polyolefin composition can represent 30 to 70% of the total thickness of the multilayer film. All individual values ​​and subranges between 30 and 70% are included and disclosed herein, for example, the first layer can represent a lower limit of 30, 35, or 40 to an upper limit of 55, 65, or 70% of the thickness as a percentage of the total thickness of the multilayer film. For example, the first layer can be 30 to 70%, or alternatively 40 to 65%, or alternatively 50 to 65% of the total film thickness.

[0051] The multilayer films of the present disclosure may be formed using processes commonly known in the art, including blown and cast films, in which the individual layers may be coextruded. In some embodiments, the multilayer films of the present disclosure may also be oriented in the machine direction or cross direction, or in both the machine direction and the cross direction, following the film formation step.

[0052] Laminate The present disclosure also provides a laminate comprising: (i) a substrate film comprising a biaxially oriented polyethylene terephthalate film, a biaxially oriented polypropylene film, or an oriented polyethylene film; (ii) a multilayer film provided herein; and (iii) an adhesive layer comprising a polyurethane in adhesive contact with the substrate film and a first layer of the multilayer film provided herein, wherein the polyurethane has a modulus of elasticity, measured according to ASTM D412, of greater than 25 MPa when the adhesive layer is formed from a solventless adhesive, and greater than 0.30 MPa when the adhesive layer is formed from a solvent-based adhesive.

[0053] As used herein, the term "laminate" refers to a combination of two or more individually formed films and / or multilayer films that are then bonded together, for example, with an adhesive layer. The term "adhesive layer" refers to an inner layer whose primary purpose is to provide interlayer adhesion to an immediately adjacent or consecutive layer, for example, between a multilayer film and a substrate film, both of which are provided herein.

[0054] In various embodiments, the laminate of the present disclosure may be formed by laminating (i) a substrate film, (ii) a multilayer film, and (iii) an adhesive layer in adhesive contact with the substrate film and a first layer of the multilayer film, each of (i), (ii), and (iii) being as provided herein. Such lamination processes include extrusion lamination processes as are known in the art.

[0055] Base Film The substrate film of the laminate can be a biaxially oriented polyethylene terephthalate film, a biaxially oriented polypropylene film, or a uniaxially oriented polyethylene film. In various embodiments, the substrate film can be a biaxially oriented polyethylene terephthalate film, preferably having a thickness of 8 to 20 μm. In alternative embodiments, the substrate film can be a biaxially oriented polypropylene film having a thickness of 15 to 50 μm. The substrate film can also be a biaxially oriented polyethylene film or a uniaxially oriented polyethylene film having a thickness of 15 to 50 μm.

[0056] adhesive layer As provided herein, the adhesive layer comprises a polyurethane in adhesive contact with the substrate film and the first layer. In some embodiments, the adhesive layer may be formed from a solventless adhesive or a solvent-based adhesive. In embodiments, the adhesive layer is located in direct contact between the substrate film and the first layer of the first polyolefin composition, and no intervening coating or layer is applied between the substrate film and the first layer. The film surface that will be coated with the adhesive layer may be corona treated to increase the surface energy and provide sufficient wettability for the adhesive components.

[0057] In some embodiments, the adhesive layer comprises a polyurethane. In one or more embodiments, the adhesive is a two-component polyol and isocyanate mixture with optional ingredients such as catalyst and diluent. An exemplary solventless laminate two-component adhesive comprises a polyurethane with a first component that is an isocyanate-terminated prepolymer. The second component of the polyurethane is a polyester / polyether made with linear and difunctional polyols. An exemplary solvent-based adhesive layer comprises a polyurethane with a first component that is 100% polyester based on methyl ethyl ketone as diluent. The second component is an isocyanate-terminated prepolymer. For example, solvent-free adhesives suitable for use may include, by way of example and not limitation, a two-component polyurethane adhesive system using commercially available components from The Dow Chemical Company (Midland, MI, USA) under the name MOR-FREE™, including (1) MOR-FREE™ 698A + MOR-FREE™ C79, or (2) MOR-FREE™ 698A + polypropylene glycol (e.g., Mn446). Examples of solvent-based adhesives suitable for use may include, by way of example and not limitation, a two-component polyurethane adhesive system using commercially available components from The Dow Chemical Company, such as (1) ADCOTE™ 563EA + Catalyst F, or (2) ADCOTE™ 811 + MOR-FREE™ 200C. The above adhesive layer composition provides an adhesive layer with an elastic modulus of greater than 25 MPa when the adhesive layer is formed from a solvent-free adhesive, and an adhesive layer with an elastic modulus of greater than 0.30 MPa when the adhesive layer is formed from a solvent-based adhesive. Elastic modulus is measured for polyurethanes according to ASTM D412.

[0058] In various embodiments, the adhesive layer may have a thickness of 1 to 5 μm. In one particular embodiment, the adhesive layer has a thickness of about 0.5 g / m 2 ~5g / m 2 , more preferably 1 g / m 2 ~3g / m 2The adhesive layer may be applied to the first and second films in any suitable manner. For example, the methods of the present disclosure may include, by way of example and not limitation, the use of a laminating machine, gravure coating, roll coating, wire rod coating, flexographic printing, spray coating, screen printing, and the like.

[0059] Film forming techniques The multilayer film and / or laminate of the present disclosure can be formed using techniques known in the art.For example, the multilayer film having both the first layer made from the first polyolefin composition provided in the present disclosure and the sealant layer made from the polyolefin composition can be made by using conventional simple bubble or cast extrusion techniques, as well as by using more sophisticated techniques such as "tenter framing" or "double bubble" processes.The terms "stretched" and "oriented" are used in the art and are used interchangeably herein, but the orientation is actually the result of the film being stretched, for example, by pressing internal air pressure on a tube or by a tenter frame pulling the edge of the film.

[0060] A simple bubble film process is described, for example, in The Encyclopedia of Chemical Technology, Kirk-Othmer, Third Edition, John Wiley & Sons, New York, 1981, Vol. 16, pp. 416-417 and Vol. 18, pp. 191-192, the disclosures of which are incorporated herein by reference. Processes for producing biaxially oriented films, such as the "double bubble" process described in U.S. Pat. No. 3,456,044 (Pahlke), and other suitable processes for preparing biaxially stretched or oriented films are described in U.S. Pat. No. 4,865,902 (Golike et al.), U.S. Pat. No. 4,352,849 (Mueller), U.S. Pat. No. 4,820,557 (Warren), U.S. Pat. No. 4,927,708 (Herran et al.), U.S. Pat. No. 4,963,419 (Lustig et al.), and U.S. Pat. No. 4,952,451 (Mueller), the disclosures of each of which are incorporated herein by reference. Multilayer film structures can also be made as described in tenter frame techniques such as those used for oriented polypropylene.

[0061] In the blown bubble process, the multilayer films of the present disclosure can be formed using high blow-up ratios, for example, 2.5:1 or higher. The blow-up ratio, abbreviated as "BUR" herein, is calculated by the equation: BUR = bubble diameter / die diameter. Other multilayer film manufacturing techniques include those described in Packaging Foods With Plastics, by Wilmer A. Jenkins and James P. Harrington (1991), pp. 19-27, and "Coextrusion Basics" by Thomas I. Butler, Film Extrusion Manual: Process, Materials, Properties pp. 31-80 (published by TAPPI Press (1992)), the disclosures of which are incorporated herein by reference.

[0062] The laminate of the present disclosure can also be formed from known techniques. Such lamination processes include extrusion lamination processes as known in the art, where the lamination process for bonding layers is performed as a secondary operation of the final layer film forming process. The lamination process bonds the multilayer film with the substrate film using adhesive layers provided herein, and such processes are described in KR Osborn and WA Jenkins in "Plastic Films, Technology and Packaging Applications" (Technomic Publishing Co., Inc. (1992)). The multilayer film and / or laminate can also undergo other post-extrusion techniques, such as biaxial orientation processes.

[0063] Other layers may also be included in the laminate forming process. For example, the laminates of the present disclosure may also include other layers, including but not limited to barrier layers, and / or tie layers, and / or structural layers. A variety of materials may be used for these layers, some of which are used as two or more layers in the same laminate structure. Some of these materials include foil, nylon, ethylene / vinyl alcohol (EVOH) copolymer, polyvinylidene chloride (PVDC), polyethylene terephthalate (PET), oriented polypropylene (OPP), ethylene / vinyl acetate (EVA) copolymer, ethylene / acrylic acid (EAA) copolymer, ethylene / methacrylic acid (EMAA) copolymer, LLDPE, HDPE, LDPE, nylon, graft adhesive polymers (e.g., maleic anhydride grafted polyethylene), and paper.

[0064] In various embodiments, the laminate may also include a toner or ink image printed on at least one layer of the laminate. In certain embodiments, the exterior surface of the laminate may include printing. One or more other surfaces of the film and / or multilayer film of the laminate may also include printing. Printing on the laminate may be accomplished using machines and processes known in the art, such as using corona printing, digital presses, and liquid toners / inks.

[0065] The present disclosure also provides a package comprising the laminate provided herein, such packaging can be used for liquids, solids, and / or particles, such as beverages, foods, cosmetics, and pharmaceuticals. The package can have any form suitable for holding liquids and / or solids, including, but not limited to, flexible packaging, pouches, bags, and freestanding pouches. In one embodiment, the package comprising the laminate is a freestanding pouch. Other package structures include, but are not limited to, flexible packages formed from any of the first layers and / or laminates disclosed herein. In certain aspects, the package is suitable for processing in conventional packaging equipment, including, for example, VFFS, HFFS, and Doypack equipment. EXAMPLES

[0066] Some embodiments of the present disclosure are detailed in the following examples, in which all parts and percentages are by weight unless otherwise specified. The following materials and tests are used in the examples. [Table 1-1] [Table 1-2]

[0067] Description of the Polyolefin Composition, First Layer and Method [Table 2]

[0068] Blending of polyolefin compositions A Buss Compounder MDK / E46 (Buss AG, Switzerland) equipped with a single mixing screw with an L / D ratio of 46 millimeters is used to compound the comparative (CE) and example (Ex) polyolefin compositions shown in Table 2. The temperature profile of the Buss Compounder was 190 / 200 / 210 / 210° C., the output was 12 kg / hour, and was collected after underwater pelletization and pellet drying.

[0069] Creating the first layer The first layer is produced either at lab scale using a Dr. Collin Line (die 60 mm, output 9 kg / hr, die temperature 230° C., and blow-up ratio of 2.5) and the CE and Ex polyolefin compositions found in Table 2, or at large scale using an Alpine Line 3-layer extrusion line (die 200 mm, output 100 kg / hr, die temperature 230° C., and blow-up ratio 2.5) and dry blending HDPE resin and propylene-ethylene copolymer TPE in the weight percents found in Table 2 directly in the extruder of the blown film line. The first layer has a thickness of 100 μm.

[0070] Drop dart impact test The first layer is tested with a falling dart impact test according to ISO 6603-4. The falling dart impact test evaluates the impact strength or toughness of a plastic film. The falling dart impact test uses a single dart configuration and a single drop height with varying dart weights.

[0071] Deflection Test The stress-strain behavior of the first layer is tested according to ISO178 using a Zwick Z010 Universal Testing Machine (Zwick / Roell).

[0072] Elastic modulus / secant elastic modulus test Secant modulus is determined according to ASTM D882 using a Zwick Z010 Universal Testing Machine (Zwick / Roell).

[0073] High Speed ​​Tensile Testing High tensile tests are recorded on a Zwick Roell HIT25P (Zwick / Roell) at speeds of up to 2 m / s and forces of 2.5 kN.

[0074] Drop Test The drop test is performed as follows: A staircase method is used, consisting of 20 drop events at different heights, increasing the drop height in 200 cm increments until failure occurs. The test is repeated, but now the height of each drop event is decreased by 200 cm until the sample (e.g., pouch) does not show any failure. The staircase method (ASTM D2463-10b test) provides a maximum non-failure height, a minimum non-failure height, and an average failure height. The average failure height represents the height at which half of the pouches tested are most likely to break, and the average failure height is used to compare the samples.

[0075] Yield stress, necking stress, and relative reduction rate for necking stress test As flow, yield stress, necking stress, and relative reduction rate for necking stress tests are performed. CE A, CE B, and Ex1 film test specimens of 70 millimeters (mm) x 15 mm are prepared. On a vibration-resistant table, a pendulum tensile impact test set (25J Pendulum Ceramic Impact Measuring Instrument) equipped to control the impact speed up to 3.8 m / s, which is the range of deformation speed in packaging applications, is set up. Two different impact tests are performed with the pendulum tensile impact test set: pure film impact tensile and heat seal impact tensile. Each test specimen is placed in a pre-established position and the pendulum is adjusted to the desired speed (position or angle). At any speed up to 3.8 m / s and a force of 2.5 kN, the stress-strain curve, maximum test force, energy, displacement, and other test parameters of the test specimen are measured. The measurement frequency is up to 4 MHz per channel. Table 3 provides the results of these tests. [Table 3]

[0076] Figure 1 presents tensile curves for 100 μm thick films prepared on a large scale using each of the CE A, CE B, and Ex 1 polyolefin compositions provided herein. The data for CE C, CE D, and CE E showed similar tensile properties to those of CE B. In addition, the machine direction (MD) data shown in Table 3 is provided only for films prepared with CE A, CE B, and Ex 1, and the results obtained in the cross direction (CD) were very similar to the MD.

[0077] Toughness / rigidity balance Figure 2 depicts the toughness / stiffness balance of 100 μm thick films (single and coextruded films) prepared at large and laboratory scales as discussed above using each of the blends of CE A, CE B, and Ex1 provided herein. The 100 μm thick films are either single 100 μm layers formed with each of the blends of CE A, CE B, and Ex1, or multilayer films formed by coextrusion of three separate layers of the same blend with either CE A, CE B, or Ex1.

[0078] As seen in Figure 2, there is a significant and surprising increase in toughness for films formed with the Ex1 blend compared to films formed with either CE A or C EB. This observation is valid for films made on a lab scale: single 100 μm film (dart drop energy x 2.90), coextruded film (dart drop energy x 2.59), or on a larger scale: single 100 μm film (dart drop energy x 1.75), coextruded film (dart drop energy x 2.39). This data highlights the toughness performance of VERSIFY™ DE2400.05 (Ex1) compared to other thermoplastic polyolefin elastomers (TPEs) such as ENGAGE™ 8842 (CE B), which increases dart drop performance by only 1.17-1.22, depending on the type of film studied.

[0079] The addition of TPE also affects stiffness: the addition of 10% VERSIFY™ DE2400.05 to Ex1 results in a 20% decrease in Young's modulus at large scale, which is within the expected range of stiffness decrease when this concentration of TPE is used in an HDPE matrix.

[0080] Laminates using PET / monoextruded film and PET / coextruded film A commercially available bi-oriented PET film (BOPET) with a thickness of 12 microns was used. The film was purchased from Mitsubishi Polyester Film under the trade name HOSTAPHAN. Laminates of BOPET with coextruded and monoextruded films were produced on a NORDMECCANICA LABOCOMBIL 400 using the lamination adhesive system in Table 1.

[0081] BOPET / monoextruded and coextruded films were produced with several solvent-free and solvent-based rigid and flexible adhesives. The details of the adhesives used are listed in Table 4. [Table 4]

[0082] In Table 4, polyurethane adhesives were classified from rigid to flexible by considering the following features: (1) average functionality - the higher the average functionality, the more rigid the adhesive and vice versa, (2) weight % aromatic / aliphatic - the higher the concentration of aromatics, the more rigid the adhesive and vice versa, (3) mole % fraction of ether, ester, and urethane groups - the higher the concentration of ethers, the more flexible the adhesive. In contrast, the higher the concentration of esters and urethanes, the more rigid the adhesive, (4) theoretical Hansen solubility parameter - this parameter accounts for the polarity of the system. The higher the Hansen solubility parameter, the better the adhesive's adhesion to polar substrates.

[0083] Laminated body using BOPET / single extrusion film [Table 5]

[0084] Figure 3 compares the limit drop heights of laminates prepared with the range of adhesives listed in Table 4. Laminates were prepared with 12 μm thick BOPET film and 100 μm films of CE A blended formulation, CE B blended formulation, or the blended formulation of Example 1, as seen in Table 5 above. As shown in Figure 3, higher drop performance values ​​are reached when using laminates containing TPE in conjunction with the use of a stiff adhesive (solvent-based or solvent-free).

[0085] Sealing performance PET / Coextruded Film Laminates: Tensile Properties and Drop Heights performance Drop height performance can be related to seal performance. Testing seal performance using high speed tensile testing is discussed above. The results obtained for seals using the laminates used in the drop height testing are summarized in Tables 6 and 7. [Table 6] [Table 7]

[0086] The seal strength study, as seen in Tables 6 and 7 above, highlights that maximum seal performance was observed when films made with Ex1 blend formulation were used together with stiff solvent-based adhesives.

[0087] Figure 4 summarizes the tensile properties of laminates made with PET / coextruded films using several adhesives. As with the study on laminates made with monoextruded films, this study highlights that using the association of laminates containing VERSIFY™ DE2400.05 elastomer with a solvent-free adhesive in the coextruded film (Example 1) reaches higher performance in terms of stress, strain at break, and most importantly, failure height.

[0088] As seen above, the addition of thermoplastic polyolefin elastomers, especially VERSIFY™ TPE, to thin films (up to 100 μm) allows a significant increase in the impact resistance of HDPE films while limiting the loss of stiffness. Furthermore, the addition of TPEs (e.g., VERSIFY™ TPE) to a monolayer or coextrusion layer laminated with a PET layer to form a pouch produces a significant and surprising improvement in the drop performance of the freestanding pouch, especially when the films seen herein are laminated with solventless stiff adhesives.

[0089] Additional examples of multilayer films of the present disclosure include a blow-up ratio of 2.5 and a blow-up ratio of 25 / 5 100% polyester fiberglass laminate formed on an Alpine 3-layer extrusion line with each layer having a thickness percentage of 0 / 25. 0 micrometers in total thickness, and a three-layer structure (A / B / C) in which A is ELITE™ 5940ST + 10% VERSIFY™ 2300, B However, it is ELITE(TM) 5940ST + 10% VERSIFY(TM) 2300. C is AFFINITY 1881G sealant. MOR-FREE™ sealant Adhesive system: No. 12 micron BOPET film with L+ / CR121 This multi-layer example is laminated on the rdmeccanica pilot line. Convert the laminate into a water-filled self-supporting pouch (SUP) according to the staircase method. A pouch drop test was performed on these pouches using a pouch drop tester to determine the remaining limit pouch drop height ( Determine the height at which 50% of the pouches will fail / break when dropped. The average pouch remaining drop height for Versify 2 was 291 mm. The present invention relates to a medium to high density core layer modified with a small amount of an elastomeric material such as 300. In the system, a reference film of 0.920 g / cm3 made with DOWLEX™ 50656G was used. The critical drop height of the much stiffer PE film (compared to the PE film) is very similar. This shows that it is possible to achieve a lower height, which is simply achieved by using a medium / high density film alone. In addition, this data does not support the proper degradation of the stiffer PE film. To ensure the performance of the test, AFFINITY 1881 or DOWLEX This indicates the need for a suitable sealant layer such as 5056G (LLDPE). The stiffer PE film ensures that the drop test performance of the liquid-filled SUP is not compromised. This makes it possible to use thinner PE films. The present application also relates to the following aspects: (1) A multilayer film, A first layer formed from a first polyolefin composition, the first polyolefin composition comprising: (a) 80 to 99.9 weight percent (wt%), based on the total weight of the first polyolefin composition, of 0.935 to 0.966 g / cm, as measured in accordance with ASTM D792 3 and a melt index (I) of 0.3 to 8 g / 10 min measured at 190 °C / 2.16 kg according to ASTM D-1238. 2 ), and (b) containing at least 60% by weight of units derived from propylene and at least 0.1% by weight of units derived from ethylene, and having a viscosity of 0.850 to 0.900 g / cm, as measured in accordance with ASTM D792; 3 and melt index (I) of 0.1 to 15 g / 10 min measured at 230 °C / 2.16 kg according to ASTM D-1238. 2 a first layer consisting essentially of 0.1 to 20 weight percent of a propylene-ethylene copolymer thermoplastic elastomer (TPE), based on the total weight of the first polyolefin composition; a sealant layer on the first layer. (2) The multilayer film according to (1) above, wherein the propylene-ethylene copolymer TPE has a melting temperature of 50 to 130° C. as determined by DSC Tm peak. (3) The multilayer film according to (1) above, wherein the propylene-ethylene copolymer TPE has a flexural modulus of 20 to 60 megapascals (MPa) as measured in accordance with ASTM D790. (4) The multilayer film according to any one of (1) to (3), wherein the first polyolefin composition comprises 90 to 98% by weight of the HDPE resin and 2 to 10% by weight of the propylene-ethylene copolymer TPE. (5) The multilayer film according to any one of (1) to (4), wherein the first layer formed from the first polyolefin composition has a thickness of 30 to 150 micrometers (μm). (6) The sealant layer has a thickness of 0.880 to 0.915 g / cm, which is 50 to 100 weight percent of the sealant layer. 3 and a melt index I of 0.5 to 5 g / 10 min measured at 190 °C / 2.16 kg according to ASTM D-1238 2 and a polyethylene having a peak melting point in the range of 85° C. to 105° C., and a molecular weight distribution Mw / Mn in the range of 2.0 to 3.0. (7) A laminate comprising: (i) a substrate film, comprising a biaxially oriented polyethylene terephthalate film, a biaxially oriented polypropylene film, or an oriented polyethylene film; (ii) a multilayer film according to any one of (1) to (6) above; (iii) A laminate comprising: an adhesive layer comprising a polyurethane in adhesive contact with the base film and the first layer of the multilayer film according to any one of (1) to (6), wherein the modulus of elasticity of the polyurethane, measured according to ASTM D412, is greater than 25 MPa when the adhesive layer is formed from a solventless adhesive, and greater than 0.30 MPa when the adhesive layer is formed from a solvent-based adhesive. (8) The laminate according to (7) above, wherein the base film is a biaxially oriented polyethylene terephthalate film having a thickness of 8 to 20 μm. (9) The laminate according to (7) above, wherein the base film is a biaxially oriented polypropylene film having a thickness of 15 to 50 μm. (10) The laminate according to (7) above, wherein the base film is a biaxially oriented polyethylene film or a uniaxially oriented polyethylene film having a thickness of 15 to 50 μm. (11) The laminate according to any one of (7) to (10) above, wherein the adhesive layer has a thickness of 1 to 5 μm. (12) The laminate according to any one of (7) to (11), wherein the first polyolefin composition of the first layer of the multilayer film contains 5 to 15% by weight of the propylene-ethylene copolymer TPE. (13) A package comprising the laminate according to any one of (7) to (12). (14) The package according to (13) above, wherein the package is a self-supporting pouch. (15) The multilayer film according to any one of (1) to (6) above, wherein the film is a blown film or a cast film.

Claims

1. A laminate comprising: (i) a substrate film, comprising a biaxially oriented polyethylene terephthalate film, a biaxially oriented polypropylene film, or an oriented polyethylene film; (ii) A multilayer film, comprising: A first layer formed from a first polyolefin composition, (a) 80 to 99.9 weight percent (wt %), based on the total weight of the first polyolefin composition, of a high density polyethylene (HDPE) resin having a density of 0.935 to 0.966 g / cm 3 as measured in accordance with ASTM D792, and a melt index (I 2 ) of 0.3 to 8 g / 10 minutes as measured at 190° C. / 2.16 kg in accordance with ASTM D-1238; and (b) 0.1 to 20 weight percent, based on the total weight of said first polyolefin composition, of a propylene-ethylene copolymer thermoplastic elastomer (TPE) comprising at least 60 weight percent units derived from propylene and at least 0.1 weight percent units derived from ethylene, and having a density of 0.850 to 0.900 g / cm 3 as measured in accordance with ASTM D792, and a melt index (I 2 ) of 0.1 to 15 g / 10 min as measured at 230° C. / 2.16 kg in accordance with ASTM D-1238; a first layer consisting essentially of: a sealant layer on the first layer; and (iii) an adhesive layer comprising a polyurethane in adhesive contact with the substrate film and the first layer of the multilayer film, the polyurethane having a modulus of elasticity, measured according to ASTM D412, of greater than 25 MPa when the adhesive layer is formed from a solventless adhesive, and greater than 0.30 MPa when the adhesive layer is formed from a solvent-based adhesive.

2. 2. The laminate according to claim 1, wherein the substrate film is a biaxially oriented polyethylene terephthalate film having a thickness of 8 to 20 μm.

3. The laminate described in claim 1, wherein the base film is a biaxially oriented polypropylene film having a thickness of 15 to 50 μm.

4. The laminate described in claim 1, wherein the base film is a biaxially oriented polyethylene film or a uniaxially oriented polyethylene film having a thickness of 15 to 50 μm.

5. A laminate described in any one of claims 1 to 4, wherein the adhesive layer has a thickness of 1 to 5 μm.

6. The laminate of any one of claims 1 to 5, wherein the first polyolefin composition of the first layer of the multilayer film comprises 5 to 15 wt% of the propylene-ethylene copolymer TPE.

7. The laminate according to any one of claims 1 to 6, wherein the multilayer film is a blown film or a cast film.

8. The laminate of claim 1, wherein in the multilayer film, the propylene-ethylene copolymer TPE has a melting temperature of 50 to 130° C., as obtained at the DSC Tm peak.

9. The laminate of claim 1, wherein in the multilayer film, the propylene-ethylene copolymer TPE has a flexural modulus of 20 to 60 megapascals (MPa) as measured in accordance with ASTM D790.

10. A laminate described in any one of claims 1 to 9, wherein in the multilayer film, the first polyolefin composition has 90 to 98 weight % of the HDPE resin and 2 to 10 weight % of the propylene-ethylene copolymer TPE.

11. A laminate described in any one of claims 1 to 10, wherein in the multilayer film, the first layer formed from the first polyolefin composition has a thickness of 30 to 150 micrometers (μm).

12. The laminate of any one of claims 1 to 11, wherein in the multilayer film, the sealant layer comprises 50 to 100 weight percent of the sealant layer polyethylene having a density of 0.880 to 0.915 g / cm3, a melt index I2 of 0.5 to 5 g / 10 min measured at 190°C / 2.16 kg in accordance with ASTM D-1238, a peak melting point in the range of 85°C to 105°C, and a molecular weight distribution Mw / Mn in the range of 2.0 to 3.

0.

13. A package comprising a laminate according to any one of claims 1 to 12.

14. The package of claim 13, wherein the package is a self-supporting pouch.

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