Recyclable flexible film and bag for packaging flowable materials

Abstract

The present disclosure provides coextruded multilayer films based on ethylene / α-olefin copolymers, including barrier films and non-barrier films, and provides articles including the films, such as flexible bags and containers for flowable materials. The films and articles including the films have improved flex crack resistance and toughness. The films and articles including the films have good barrier properties because the barrier films include a core layer of ethylene-vinyl alcohol (EVOH) copolymers with high ethylene content. A small amount of EVOH copolymer in the total film is required to achieve the flex crack resistance, toughness and good barrier properties, and also allows the films and articles to be recycled.

Description

Technical Field

[0001] Related Applications

[0002] This application is related to and claims priority to U.S. Provisional Patent Application No. 62 / 990,540 filed on March 17, 2020 and U.S. Provisional Patent Application No. 63 / 054,309 filed on July 21, 2020, the disclosures of which are each incorporated herein by reference in their entirety for all purposes. Technical Field

[0004] The present disclosure relates to coextruded multilayer (CEML) films based on ethylene / α-olefin copolymers that can be used to make flexible bags (e.g., for storing, containing, transporting, packaging and / or storing flowable materials). The CEML films can be used to make and provide flexible bags that can exhibit improved flex crack resistance, toughness, and have good barrier properties while being recyclable. The CEML films and flexible bags containing the films achieve these performance characteristics through a combination of materials not utilized in the prior art (e.g., by including a barrier ethylene-vinyl alcohol (EVOH) copolymer core layer comprising a high % ethylene content (e.g., greater than 32%), wherein the barrier core layer accounts for less than about 5% of the total film thickness or weight). Background Art

[0005] Bags for packaging flowable liquid products such as food and beverage products are typically made using bag forming equipment where multiple rolls of film are unwound to form bags. The bags are then coded and then punched to form a hole for the spout. The spout is inserted and the bag is sealed on the long sides, usually brushed to remove air. It is then cross-sealed at its bottom and on top of the next bag being made and pulled through the production line. The bag is perforated near the cross-seal and packaged for a bag-in-box fill line.

[0006] Customers are demanding bags with thinner films, especially when packaging flowable / liquid products. This presents a challenge because most commercially available films cannot meet these desired physical parameters while also providing insufficient seal strength and toughness. As a result, the performance of the bags has been affected, especially those filled with frozen products or products that must be refrigerated during use, storage and transportation. Flexible bags of 1-6 gallon scale sizes made from currently available films show significantly reduced performance, especially when refrigeration is required. These bags may also be affected by inefficient emptying or emptying of contents, and may require the addition of devices that help to completely empty the flowable contents contained in the bag. In addition, fluctuating temperature environments can create other problems in the handling, transportation and distribution of filled bags. Leakage is a systematic and recurring problem for such bags due to frequent tearing and seal rupture, mainly in the side and bottom seals and the area around the mouth of the bag.

[0007] Beverage bags based on the outer barrier layer of the heat laminate or adhesive laminate comprising the two-way nylon 6 core sandwiched between the polyethylene / EVA sealing layers are widely used. The inner layer of these beverage bags usually comprises polyethylene. Other bags for packaging various liquids are based on the heat laminate or adhesive laminate comprising the two-way oriented PET with vacuum deposited metal coating to provide a high oxygen barrier structure. However, the flexible bags comprising two-way oriented nylon 6 or metallized PET of these types are not suitable for recycling, and are therefore not as desirable, sustainable or environmentally friendly as recyclable materials.

[0008] Therefore, there is a need in the art to provide a multilayer film that provides a package (bag) with excellent toughness and durability, thereby withstanding the relatively low temperatures and temperature changes commonly encountered during use, transportation, and handling. Given the savings that such bags can achieve (e.g., savings in material and manufacturing costs), there is also a need for a flexible bag that can be emptied of the bag contents (i.e., without any emptying aids). As shown in the following disclosure, the inventors have developed a film structure that can provide the desired toughness and durability, substantially eliminating tearing and seal rupture of bags produced using the film. The film and bags containing the film have good barrier properties, good flex crack resistance, and excellent self-emptying properties, while also being recyclable, thereby improving downstream sustainability. Summary of the invention

[0009] The present disclosure generally provides coextruded barrier films, bags comprising the coextruded films optionally in combination with one or more non-barrier films, packaged flowable products comprising the coextruded barrier films and / or bags, which contain an amount of barrier material that provides good barrier properties, toughness, flex crack resistance and durability while also being recyclable.

[0010] In one aspect, the present disclosure relates to a coextruded multilayer polymer barrier film comprising at least three layers: (i) an inner sealant layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of 0.910 to 0.924 g / cm 3 (ii) a core barrier layer comprising ethylene vinyl alcohol (EVOH) of about 0.1% to about 10% by weight or total thickness of the coextruded multilayer polymer film, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iii) an outer sealant layer comprising a density of 0.894 to 0.920 g / cm 3The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the total density of the outer seal layer is about 0.910 to 0.924 g / cm2. 3 within the range.

[0011] In one aspect, the present disclosure relates to a coextruded multilayer polymer barrier film comprising at least three layers: (i) an inner sealant layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of 0.910 to 0.924 g / cm 3 (ii) a core barrier layer comprising ethylene vinyl alcohol (EVOH) in an amount of about 0.1% to about 5% by weight or thickness of the coextruded multilayer polymer film, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iii) an outer sealant layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the total density of the outer seal layer is about 0.910 to 0.924 g / cm2. 3 within the range.

[0012] In another aspect, the present invention relates to a coextruded multilayer polymer film comprising five layers: (i) an inner sealing layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total inner seal layer, wherein the total density of the inner seal layer is about 0.910 to 0.924 g / cm2. 3 (ii) a first insertion layer and a second insertion layer, wherein the insertion layer comprises a density of 0.894 to 0.920 g / cm 3 The invention relates to an ethylene / α-olefin copolymer fraction in an amount of at least about 50% by weight or thickness of the first insert layer and an adhesive or adhesive resin in an amount effective to improve the adhesion of the first insert layer and the second insert layer to at least one other layer of the coextruded multilayer polymer film, wherein the total density of the first insert layer and the second insert layer is from about 0.910 to 0.924 g / cm 3(iii) a core barrier layer comprising ethylene vinyl alcohol (EVOH) of about 0.1% to about 10% by weight or total thickness of the coextruded multilayer polymer film, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iv) an outer sealant layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the total density of the outer seal layer is about 0.910 to 0.924 g / cm2. 3 within the range.

[0013] In another aspect, the present invention relates to a coextruded multilayer polymer film comprising five layers: (i) an inner sealing layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total inner seal layer, wherein the total density of the inner seal layer is about 0.910 to 0.924 g / cm2. 3 (ii) a first insertion layer and a second insertion layer, wherein the insertion layer comprises a density of 0.894 to 0.920 g / cm 3 The invention relates to an ethylene / α-olefin copolymer fraction in an amount of at least about 50% by weight or thickness of the first insert layer and an adhesive or adhesive resin in an amount effective to improve the adhesion of the first insert layer and the second insert layer to at least one other layer of the coextruded multilayer polymer film, wherein the total density of the first insert layer and the second insert layer is from about 0.910 to 0.924 g / cm 3 (iii) a core barrier layer comprising ethylene vinyl alcohol (EVOH) in an amount of about 0.1% to about 5% by weight or thickness of the coextruded multilayer polymer film, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iv) an outer sealant layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the total density of the outer seal layer is about 0.910 to 0.924 g / cm2. 3 within the range.

[0014] In another aspect, the present invention relates to a coextruded multilayer polymer film comprising seven layers: (i) an inner sealing layer comprising a density of 0.894 to 0.920 g / cm 3The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total inner seal layer, wherein the total density of the inner seal layer is about 0.910 to 0.924 g / cm2. 3 (ii) a first outer insert layer and a second outer insert layer, and a first inner insert layer and a second inner insert layer, wherein the insert layers all contain a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 0.910 to about 0.924 g / cm 3 The invention relates to a method for preparing an ethylene-vinyl alcohol (EVOH) film having a first inner interlayer and a second inner interlayer, wherein the first inner interlayer and the second inner interlayer comprise an amount of adhesive or adhesive resin effective to improve the adhesion of the first inner interlayer and the second inner interlayer to at least one layer of the coextruded multilayer polymer film; (iii) a core barrier layer adjacent to and between the first inner interlayer and the second inner interlayer, the core barrier layer comprising ethylene vinyl alcohol (EVOH) in an amount of about 0.1% to about 10% by total weight or total thickness of the coextruded multilayer polymer film, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iv) an outer sealant layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the total density of the outer seal layer is about 0.910 to 0.924 g / cm2. 3 within the range.

[0015] In another aspect, the present invention relates to a coextruded multilayer polymer film comprising seven layers: (i) an inner sealing layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total inner seal layer, wherein the total density of the inner seal layer is about 0.910 to 0.924 g / cm2. 3 (ii) a first outer insert layer and a second outer insert layer, and a first inner insert layer and a second inner insert layer, wherein the insert layers all contain a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 0.910 to about 0.924 g / cm 3(iii) a core barrier layer adjacent to and between the first inner insert layer and the second inner insert layer, the core barrier layer comprising ethylene vinyl alcohol (EVOH) in an amount of about 0.1% to about 5% by total weight or total thickness of the coextruded multilayer polymer film, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iv) an outer sealant layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the total density of the outer seal layer is about 0.910 to 0.924 g / cm2. 3 within the range.

[0016] In an embodiment of any one of the above aspects, the coextruded multilayer polymer film may include a structure in which a first insert layer is sandwiched between the inner seal layer and the core barrier layer, and a second insert layer is sandwiched between the outer seal layer and the core barrier layer.

[0017] In some embodiments of the above aspects, the coextruded multilayer polymeric barrier film may comprise an inner and / or outer seal layer comprising an adhesive or adhesive resin in an amount effective to improve adhesion of the seal layer to the core barrier layer.

[0018] In some embodiments of any of the above aspects, the ethylene / α-olefin interpolymer in at least one of the inner seal layer, the outer seal layer, the first insert layer, or the second insert layer comprises a polymer fraction of a linear low density polyethylene and a second copolymer fraction of an ethylene / octene-1 copolymer, an ethylene / hexene-1 copolymer, or an ethylene / butene-1 copolymer.

[0019] In some embodiments of any of the above aspects, the density of the interpolymer is 0.915 g / cm 3 , the melt index is 0.80-1.0 dg / min. In other embodiments, the ethylene / α-olefin interpolymer comprises at least one density of 0.912 g / cm 3 Metallocene linear low density polyethylene (mLLDPE).

[0020] In some embodiments of any of the above aspects, the thickness percentage of the barrier layer EVOH layer relative to the entire film is selected from the following values: 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9 and 5.0. In some embodiments, the thickness percentage of the barrier EVOH layer relative to the entire film can fall within the range of about 2.5% to about 5.0% (e.g., 2.5-5.0, 2.6-5.0, 2.7-5.0, 2.8-5.0, 2.9-5.0, 3.0-5.0, 3.1-5.0, 3.2-5.0, 3.3-5.0, 3.4-5.0, 3.5-5.0, 3.6-5.0, 3.7-5.0, 3.8-5.0, 3.9-5.0, 4.0-5.0, 4.1-5.0, 4.2-5.0, 4.3-5.0, 4.4-5.0, 4.5-5.0, 4.6-5.0, 4.7-5.0, 4.8-5.0, or 4.9-5.0%), including any individual values ​​and ranges within those stated ranges.

[0021] In some embodiments of any of the above aspects, the ethylene mole percent in the EVOH copolymer is selected from a value greater than about 35 mole percent. In other embodiments, the ethylene mole percent in the EVOH copolymer is selected from 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, and 55 mole percent.

[0022] In some embodiments of any of the above aspects, the melt index of the ethylene / α-olefin interpolymer in at least one of the inner seal layer, the outer seal layer, the first insert layer, or the second insert layer is in a range of 0.2 to 2.0 dg / min.

[0023] In some embodiments of any of the above aspects, the ethylene / α-olefin interpolymer in at least one of the inner seal layer, the outer seal layer, the first insert layer, or the second insert layer has a zero shear viscosity ratio (ZSVR) in a range from 1.15 to 2.5.

[0024] In some embodiments of any of the above aspects, the molecular weight distribution of the ethylene / α-olefin interpolymer in at least one of the inner seal layer, the outer seal layer, the first insert layer, or the second insert layer is expressed as a ratio of weight average molecular weight to number average molecular weight (Mw / Mn) in the range of 2.0 to 4.0.

[0025] In some embodiments of the above aspects comprising insert layers, the first insert layer is sandwiched between the inner seal layer and the core barrier layer, and the second insert layer is sandwiched between the outer seal layer and the core barrier layer.

[0026] In some embodiments of any of the above aspects, any one or more of the sealing layer, the core layer, and the insert layer can each include from one to up to and including 45 material layers.

[0027] In one aspect, the present invention provides a bag for packaging a flowable material, the bag comprising a recyclable barrier coextruded multilayer polymer film and a non-barrier coextruded multilayer polymer film, wherein the barrier coextruded multilayer polymer film comprises (i) an inner sealing layer, the inner sealing layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total inner seal layer, wherein the total density of the inner seal layer is about 0.910 to 0.924 g / cm2. 3 (ii) a first insertion layer and a second insertion layer, wherein the insertion layer comprises a density of 0.894 to 0.920 g / cm 3 The invention relates to an ethylene / α-olefin copolymer fraction in an amount of at least about 50% by weight or thickness of the first insert layer and an adhesive or adhesive resin in an amount effective to improve the adhesion of the first insert layer and the second insert layer to at least one other layer of the coextruded multilayer polymer film, wherein the total density of the first insert layer and the second insert layer is from about 0.910 to 0.924 g / cm 3 (iii) a core barrier layer comprising ethylene vinyl alcohol (EVOH) of about 0.1% to about 5% by weight or thickness of the coextruded multilayer polymer film or of the combined weight or thickness of the barrier film and non-barrier film, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iv) an outer sealant layer comprising a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is in the range of about 100 to about 200 g / cm2 and is used in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the total density of the outer seal layer is about 0.910 to 0.924 g / cm2. 3 within the range.

[0028] In some embodiments of the above aspects, the bag can include a first outer insert layer and a second outer insert layer, and a first inner insert layer and a second inner insert layer, wherein the insert layers all include a density of 0.894 to 0.920 g / cm 3 The ethylene / α-olefin copolymer fraction is within a range of about 0.910 to about 0.924 g / cm 3 The invention relates to a method for preparing an insulating film comprising: providing a first inner insert layer and a second inner insert layer comprising an amount of adhesive or adhesive resin effective to improve the adhesion of the first inner insert layer and the second inner insert layer to at least one layer of the coextruded multilayer polymer film; wherein the core barrier layer is adjacent to and located between the first inner insert layer and the second inner insert layer.

[0029] In some aspects, the present disclosure provides a packaging product comprising the coextruded multilayer polymeric barrier film described herein.

[0030] In some aspects, the present disclosure provides a packaging product comprising a bag for packaging a flowable material as described herein.

[0031] In some aspects, the present disclosure provides a method of making the coextruded multilayer polymeric barrier films described herein.

[0032] In some aspects, the present disclosure provides a method of making a bag for packaging a flowable material as described herein.

[0033] In some aspects, the present disclosure provides a method of packaging a flowable product comprising the coextruded multilayer polymeric barrier film described herein.

[0034] In some aspects, the present disclosure provides a method of packaging a flowable product, the method comprising the bag described herein.

[0035] Other aspects and embodiments of the disclosure will be apparent to those of ordinary skill in the art in view of the following description and illustrative examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figures 1A to 1D Shown are a series of general schematic depictions of multilayer non-barrier films according to several exemplary aspects and embodiments described herein. Figure 1A An exemplary embodiment of a three-layer non-barrier film is depicted. Figure 1B Five layers of non-barrier film are depicted. Figure 1C Seven layers of non-barrier film are depicted. Figure 1DA seven-layer non-barrier film is depicted, with four of the seven layers comprising multiple individual layers of the same material stacked together to form the entire layer.

[0037] FIG. 2A to FIG. 2D Shown are a series of general schematic depictions of multilayer barrier films according to several exemplary aspects and embodiments described herein. Figure 2A An exemplary embodiment of a three-layer barrier film is depicted wherein the inner layer comprises a barrier layer. Figure 2B A five layer barrier film is depicted, wherein the inner layer comprises a barrier layer. Figure 2C A seven layer barrier film is depicted, wherein the inner layer comprises a barrier layer. Figure 2D A seven-layer non-barrier film is depicted, with five of the seven layers (including the inner barrier layer) comprising multiple individual layers of the same material stacked together to form the entire layer.

[0038] FIG. 3A to FIG. 3D Shown are a series of general schematic depictions of 2-layer film structures including multiple layers of barrier and non-barrier films according to several exemplary aspects and embodiments described herein. Figure 3A Describes the following: Figure 1A and Figure 2A An exemplary embodiment of a 2-layer film structure of three layers of non-barrier and barrier films is shown, wherein the "outer" layer comprises the barrier layer and the "inner" layer comprises the non-barrier layer. FIG. 3A to FIG. 3D In each of the embodiments shown, the outer and inner sheets are not connected together (sealed) except at the edges to form a bag. Over most of the surface area between the sheets, the sheets can be considered to be "free floating" relative to each other. Figure 3B Describes the following: Figure 1B and Figure 2B An exemplary embodiment of a 2-layer film structure of five layers of non-barrier and barrier films is shown, wherein the "outer" layer comprises the barrier layer and the "inner" layer comprises the non-barrier layer. Figure 3C Describes the following: Figure 1B and Figure 2C Depicted are exemplary embodiments of a 2-layer film structure of five layers of non-barrier and seven layers of barrier film, wherein the "outer" plies comprise the barrier layers and the "inner" plies comprise the non-barrier layers. Figure 3D Describes the following: Figure 1D and Figure 2D An exemplary embodiment of a 2-layer film structure of seven layers of non-barrier and barrier films is shown, wherein five of the seven layers of the "outer" barrier layer (including the inner barrier layer) and four of the seven layers of the "inner" non-barrier layer comprise multiple individual layers of the same material stacked together to form the entire layer.

[0039] Figure 4A and Figure 4BA general depiction of a flexible bag (22) in an unfilled form (4A) and containing a flowable product (4B) is provided according to an exemplary embodiment of the present disclosure, wherein the bag includes at least one spout (50) that can be located at different locations on the bag, and a sealed perimeter (34, 38, 54, 42) defining a volume (26) for containing the flowable contents. DETAILED DESCRIPTION

[0040] Before proceeding with further details regarding the present disclosure, it is to be understood that the present disclosure is not limited to specific materials (including polymers, copolymers, interpolymers, additives, etc.), structures and arrangements (including the number of individual layers in a film, the number of layers in a film, the order of layers, and the layers of a film, etc.), or process steps, as well as intended or contemplated applications and uses, as these may vary and still fall within the scope of the description provided herein.

[0041] The percentages described in the present disclosure generally refer to the weight percentage or thickness percentage of the total weight or total thickness of the composition, and are generally indicated when narrating. Although differences in the density of the components (polymers, copolymers, with or without additives) may result in differences between the percentages expressed by weight relative to the percentages expressed by thickness, the two percentage values ​​are generally very close to each other. Unless otherwise stated, all ratios described in this patent application are in weight:weight.

[0042] Ranges are merely used as a shorthand form to avoid listing and describing each and every value within the range. Any suitable value within the range can be selected as the upper limit, lower limit or endpoint of the range.

[0043] Unless the context clearly indicates otherwise, the singular form of a word includes its plural form and vice versa. Thus, references to "a," "an," and "the" generally include plural forms of the corresponding terms they define. For example, reference to "a method" includes its plural form "multiple methods." Similarly, the term "comprising," whether used as a transitional phrase in a claim or otherwise, should be interpreted inclusively and not exclusively. Similarly, the terms "including," "having," and "or" should be deemed inclusive unless the context clearly prohibits such an interpretation. Similarly, the term "example," particularly when followed by a list of terms, is intended to be merely exemplary, illustrative, and non-limiting, and therefore should not be considered exclusive or exhaustive.

[0044] Unless otherwise defined, all technical and scientific terms, technical terms and acronyms used in this disclosure have the meanings commonly understood by those of ordinary skill in the relevant technical fields in which the terms are used. Although any compositions, methods, articles or other means or materials similar or equivalent to those described in this disclosure can be used to practice various aspects and embodiments herein, the description of specific compositions, methods, articles or other means or materials is for illustration and clarity purposes only.

[0045] All patents, patent applications, publications, technical and / or scholarly papers, and other references cited or mentioned herein are incorporated by reference in their entirety to the extent permitted by law. Discussion of these references is intended only to summarize the assertions made in these references. No admission is made that any such patent, patent application, publication, or reference, or any portion thereof, is material or prior art relevant to the scope of the present disclosure or claims.

[0046] As used herein, the term "flowable material" does not include gaseous materials, powders or other solid materials, but includes any liquid material that flows or can be pumped under gravity. Such materials include liquids (e.g., syrups, mixtures, alcohol, milk, water, juices, oils, etc.), semisolids, and liquid emulsions (e.g., ice cream, ice cream mixes, soft margarine, whipped cream, dough, etc.). The aspects and embodiments described herein are particularly suitable for flowable foods and beverages, including those that can be packaged at ambient or refrigerated temperatures.

[0047] As used herein, "density" is determined by ASTM D 792 and "melt index" of a polymer is determined by ASTM D 1238. The "melting point" of a polymer is the peak melting point as measured by differential scanning calorimetry (DSC) as described in ASTM procedure D3417-83 (Rev. 88).

[0048] Figures 1A to 1D A general schematic depiction of a multilayer non-barrier film (100) according to an exemplary embodiment of the present disclosure is provided. Figure 1A As shown, the coextruded non-barrier film according to the present disclosure generally includes multiple layers, which can be the same or different. The core layer (110) and the sealing layer (120) (either of which can be the same or different polymer or copolymer materials) can be coextruded to form the non-barrier film (100). In some exemplary embodiments, the non-barrier film may not include a core layer (i.e., only two layers). Figure 1B An exemplary embodiment of a five-layer non-barrier film (100) having a core layer (110), outer and inner sealant layers (120), and outer and inner insert layers (130) is shown. Figure 1CAn exemplary embodiment of a seven-layer non-barrier film (100) according to the present invention is depicted having a core layer (110), outer and inner sealing layers (120), first outer and inner insert layers (130), and second and third outer and inner insert layers (140). Figure 1D Describes something like Figure 1C The exemplary embodiment shown and includes a seven-layer non-barrier film (100) having a similar core layer (110) and a second outer insert layer and an inner insert layer (140), but also illustrates an exemplary embodiment in which the outer sealing layer and the inner sealing layer (1201) and the first outer insert layer and the inner insert layer (1301) include multiple individual layers of the same material stacked to form the entire layer.

[0049] FIG. 2A to FIG. 2D A general schematic depiction of a multilayer barrier film (200) is provided according to several exemplary aspects and embodiments described herein. FIG. 2A to FIG. 2D The exemplary diagrams and structures in Figures 1A to 1D Those described are similar, but do not require that the multilayer barrier film and the non-barrier film be similarly structured or symmetrical, as discussed in more detail herein. In addition, FIG. 2A to FIG. 2D as well as FIG. 3A to FIG. 3D The barrier film (200) according to the present invention is shown to include a core barrier layer (210), (2101) of ethylene vinyl alcohol (EVOH). Figure 2A An exemplary embodiment of a three-layer barrier film (200) is provided, having inner and outer sealing layers (220) which may be the same or different materials, and a core barrier layer (210) comprising an EVOH barrier material that may be coextruded to form the barrier film (200). Such embodiments suitably include an adhesive between the core barrier layer and the sealing layer, or the sealing layer may include an amount of adhesive material to facilitate bonding between the layers.

[0050] Figure 2BAn exemplary embodiment of a five-layer barrier film (200) having a core layer (210), an outer sealing layer and an inner sealing layer (220), and a first inner insert layer and an outer insert layer (230) is shown. Any of the outer sealing layer and the inner sealing layer (220) and the insert layer (230) can be constructed of the same polymer or copolymer material, or can be constructed of different polymer or copolymer materials. Therefore, in some exemplary embodiments, the polymer or copolymer used for the outer sealing layer and the inner sealing layer (220) can be different and can have different thicknesses. In similar exemplary embodiments, the polymer or copolymer used for the inner insert layer and the outer insert layer (230) can be different and can have different thicknesses. In some other exemplary embodiments, the polymer or copolymer used for all outer sealing layers and inner sealing layers (220) and inner insert layers and outer insert layers (230) can be the same material and have approximately the same thickness.

[0051] Figure 2C An exemplary embodiment of a seven-layer barrier film (200) having a core layer (210), an outer sealing layer and an inner sealing layer (220), a first outer insert layer and an inner insert layer (230), and a second outer insert layer and an inner insert layer (240) is shown. Any of the outer sealing layer and the inner sealing layer (220), the first insert layer and the second insert layer (230), (240) can be constructed of the same polymer or copolymer material, or can be constructed of different polymer or copolymer materials. Therefore, in some exemplary embodiments, the polymer or copolymer used in any of the sealing layers (220) can be different and can have different thicknesses. In similar exemplary embodiments, the polymer or copolymer used in the first insert layer and the second insert layer (230), (240) can be different and can have different thicknesses. In some other exemplary embodiments, the polymer or copolymer used in all of the outer sealing layers and the inner sealing layer (220) and the first insert layer and the second insert layer (230), (240) can be the same material and have approximately the same thickness.

[0052] Figure 2D Shows that with Figure 2C An exemplary embodiment of a seven-layer barrier film (200) of a general structure similar to the described embodiment, wherein five of the seven layers, including the inner core barrier layer (2101), the outer sealing layer and the inner sealing layer (2201), and the first outer insert layer and the inner insert layer (2301), comprise multiple individual layers of the same material stacked to form the entire layer.

[0053] Although not necessarily in proportion, Figures 2A to 2D or FIG. 3A to FIG. 3DAs shown in any of and as described in various aspects and embodiments herein, the present disclosure provides a film comprising an EVOH core barrier layer constituting 5% or less (by weight or thickness) of the total film.

[0054] FIG. 3A to FIG. 3D A series of exemplary embodiments according to the present invention are shown that may include a 2-layer film structure that may include a multilayer barrier film and a non-barrier film as described in various aspects and embodiments herein. Figure 3A It shows that the Figure 1A and Figure 2A Depicted is an exemplary embodiment of a 2-layer film structure of three layers of non-barrier film (100) and barrier film (200), wherein the "outer" layer comprises the barrier layer (200) and the "inner" layer comprises the non-barrier layer (100). FIG. 3A to FIG. 3D The ply layers in all depicted embodiments are physically connected only at the edges (represented by (310)) and therefore may include voids or gaps between two plies (300) at locations other than the sealed edges (310). Figure 3B It shows that the Figure 1B and Figure 2B Depicted is an exemplary embodiment of a 2-layer film structure of five layers of non-barrier film (100) and barrier film (200), wherein the "outer" layer comprises the barrier layer (200) and the "inner" layer comprises the non-barrier layer (100). Figure 3C It shows that the Figure 1C and Figure 2D Depicted is an exemplary embodiment of a 2-layer film structure of five layers of non-barrier film (100) and seven layers of barrier film (200), wherein the "outer" layers include barrier layers (200) and the "inner" layers include non-barrier layers (100). Figure 3D It shows that the Figure 1D and Figure 2D An exemplary embodiment of a 2-layer film structure of seven layers of non-barrier film (100) and barrier film (200) is depicted, wherein five of the seven layers of the "outer" barrier layer (200) and four of the seven layers of the "inner" non-barrier layer (100) comprise multiple individual plies of the same material stacked to form the entire layer. As discussed herein, different plies need not have the same or similar number of layers or layer structures in order to fall within the scope of the present disclosure.

[0055] Co-extruded film

[0056] In a general aspect, the present disclosure relates to coextruded (i) non-barrier films and (ii) barrier films that can be combined in a variety of ways and combinations to form multi-layer and multi-layer sheet structures, which find use in a variety of applications.

[0057] Materials and film structures of non-barrier and barrier films

[0058] In some aspects, the present disclosure provides coextruded multilayer (CEML) films that can be used for packaging liquid flowable materials, including bags for food and beverage related products, for example. In exemplary embodiments of this aspect, the present disclosure provides a CEML film that is relatively low in gauge (thickness) but exhibits excellent toughness and seal strength, including under variable temperature conditions (e.g., ambient and refrigerated conditions), as exemplified by the data provided herein, showing a high bag drop height (F50 value), as measured by the Bruceton stair drop test method.

[0059] In some embodiments, the present invention provides a non-barrier CEML (NB-CEML) film that does not include (i.e., does not include, contains, or consists of) a material that provides a barrier layer (e.g., a non-barrier embodiment does not include EVOH in any of its layers). In some embodiments, the NB-CEML may include an interpolymer and film structure as described in published U.S. Patent Application No. 2018 / 0370201, published on December 27, 2018 and incorporated herein by reference ("Bag-in-Box Film for Packaging Refrigerated Liquids"). Accordingly, aspects and embodiments of the present disclosure provide a flexible bag or bag-in-box package comprising (i) a barrier coextruded multilayer film as described herein, and (ii) a non-barrier coextruded multilayer film as described herein and / or as described, for example, in US PGPUB 2018 / 0370201, wherein the barrier film and non-barrier film are combined and edge-sealed as separate plies in the flexible bag or bag-in-box structure.

[0060] In some embodiments, the present disclosure provides a barrier CEML (B-CEML) film including a core barrier layer comprising EVOH.

[0061] In general, embodiments related to non-barrier (NB-CEML) and barrier (B-CEML) film structures may include similar or identical components, materials, thicknesses, and structures, except for the presence of an EVOH core layer in the barrier film (B-CEML). Thus, in exemplary embodiments, either or both of the barrier and non-barrier films may include a co-extruded structure that may be symmetrical or asymmetrical. In some embodiments, the film structure may include an outer sealing layer, one or more insert layers, a core layer, one or more insert layers, and an inner sealing layer.

[0062] In some embodiments related to B-CEML, the film may include one or more intervening layers between other intervening layers or inner and / or outer sealing layers and the core barrier layer. That is, in some embodiments, the B-CEML includes a first, or first and second, or first, second and third (etc.) inner and / or outer intervening layer located between the core barrier layer and the sealing layer. In embodiments including more than one intervening layer, at least one side of an intervening layer will abut / adjoin another intervening layer.

[0063] In exemplary embodiments, the coextruded multilayer film may include 1 to about 45 or 50 individual polymer film layers. In other words, the B-CEML film, the NB-CEML film, or both may include one or more polymer layers formed from multiple monolayers of the same polymer and may be selected from: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, and 50. In some embodiments, the film may include a number of layers within a range defined by any two numbers given above, including the endpoints of the range.

[0064] For example, a B-CEML and NB-CEML film comprising five layers is depicted in Figure 1B and Figure 2B Each of the Figure 3B The 2-layer (outer layer and inner layer) structure in the embodiment. According to an exemplary embodiment, the outer sealing layer and the inner sealing layer (220), (120) can be made of ethylene / α-olefin (EAO) copolymer (or "interpolymer"); the first inner insert layer and the outer insert layer (230) or the second outer sealing layer and the inner sealing layer (130) can be made of ethylene / α-olefin copolymer; the non-barrier core layer (110) can be made of LLDPE. In some embodiments, EAO (including LDPE or LLDPE) can include ethylene / octene-1, ethylene / hexane-1 or ethylene / butene-1 copolymers. In some specific other exemplary embodiments, the melt index of the EAO copolymer can be 0.8 dg / min to 1.0 dg / min, and the density is 0.912 g / cm 3 Up to 0.916g / cm 3 , or may include one or more other copolymers or combinations of copolymers falling within those physical parameters. In some embodiments, any of the barrier or non-barrier layers of the B-CEML or NB-CEML may be constructed from a single polymer layer or multiple polymer layers.

[0065] In various embodiments, the outer sealing layer and the inner sealing layer may each comprise about 10-40% of the thickness of the NB-CEML film. In some embodiments including one or more insertion layers, each insertion layer may comprise about 5-20% of the thickness of the NB-CEML film. In some embodiments involving NB-CEML films comprising a core layer, the core layer may comprise about 30-50% of the thickness of the NB-CEML film.

[0066] In some embodiments, the total thickness of the NB-CEML film is about 1-5 mils, or about 1.5-4.0 mils, or about 1.8-3.8 mils. In some embodiments related to flexible bags, the total thickness of the NB-CEML film accounts for more than 50% of the combined thickness of the NB-CEML and B-CEML films that can be used in the flexible bag. In some exemplary embodiments, the thickness of the NB-CEML layer of the flexible bag including the B-CEML layer and the NB-CEML layer can account for 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, or about 75% or more of the combined thickness of the barrier layer and the non-barrier layer. In some embodiments of the flexible bags disclosed herein, bags including a NB-CEML layer that accounts for more than 50% of the total thickness of the film forming the bag can provide good self-draining / emptying of the flowable contents without any additional emptying means.

[0067] Although many laminated films are known and are made from a variety of polymers (e.g., polyolefins) and polymer blends, such as those described in U.S. Pat. Nos. 4,503,102, 4,521,437, 5,206,075, 5,364,486, 5,508,051, 5,721,025, 5,879,768, 5,942,579, 5,972,443, 6,117,465, 6,256,966, 6,406,765, 6,416,833, and 6,767,599 (all of which are incorporated by reference in their entirety), in the aspects and embodiments described herein, the film may include one or more film layers comprising ethylene / α-olefin (EAO) copolymers. Thus, the present disclosure provides films in which one or more EAO copolymers or EAO copolymer blends can be used to form inner and outer sealant layers, insert layers, and non-barrier core layers. The EAO copolymers are selected based on one or more functional or physical properties to provide improved impact resistance and bag drop performance (particularly in cold conditions) relative to conventional bags formed from multilayer films that do not include the ethylene / α-olefin copolymers described herein.

[0068] Ethylene-α-olefin copolymer (EAO copolymer)

[0069] The present disclosure provides an EAO copolymer, which can be used within the scope of various aspects and embodiments described herein, and can include, for example, ethylene-C4 to C10-α-olefin interpolymers (copolymers). In some embodiments, the melt index of the ethylene-C4 to C10-α-olefin interpolymer (EAO copolymer) is 0.2 to 2.0 dg / min, 0.4 to 1.5 dg / min, or about 0.5 to 1.0 dg / min (g / 10min); the density is 0.890 to about 0.930 g / cm 3 (For example, specific values ​​and narrower ranges falling within this range are included, such as 0.912 g / cm 3 Up to 0.925g / cm 3 、0.910g / cm 3 、0.911g / cm 3 , 0.912g / cm 3 , 0.913g / cm 3 , 0.914g / cm 3 、0.915g / cm 3 , 0.916g / cm 3 , 0.917g / cm 3 、0.918g / cm 3 The term "interpolymer" refers to a copolymer, a terpolymer, and the like.

[0070] In some embodiments, the zero shear viscosity ratio (ZSVR) of the EAO copolymer may be in the range of about 1.15 to 2.5 (e.g., including specific values ​​and narrower ranges falling within the range). In some embodiments, the molecular weight distribution of the EAO copolymer may be expressed as a ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn) in the range of 2.0 to 4.0 (e.g., including specific values ​​and narrower ranges falling within the range).

[0071] EAO copolymers can be selected from low-density polyethylene (LDPE), including linear low-density polyethylene (LLDPE), and metallocene-derived LDPE and LLDPE (mLDPE, mLLDPE). According to some conventional industry descriptions, the density is 0.915-0.930 g / cm 3 Linear low-density polyethylene in the range can be called LLDPE, while the density is 0.900-0.915 g / cm 3 Linear low density polyethylene within the range may be referred to as ultra low density polyethylene (ULDPE) or very low density polyethylene (VLDPE).

[0072] Suitable polymers that can be used to form the various layers of the B-CEML and NB-CEML and that have the performance characteristics disclosed herein are commercially available and sold under various trade names and trademarks, including, for example, ExxonMobil Chemical (e.g., polyethylene and performance PE polymers (EXCEED TM XP, EXCEED TM 、ENABLE TM 、EXXONMOBIL TM LDPE、NEXXSTAR TM LDPE, EXXONMOBIL TM LLDPE, EXXONMOBIL TM NTX LLDPE)) and Dow Chemical (such as polyethylene (AFFINITY TM AGILITY TM 、ASPUN TM 、DOW TM LDPE, DOWLEX TM ,ELITE TM 、INNATE TM , XUS 59999.38)) and other commercial sources. A specific polymer can be selected based on specific performance characteristics as described herein (e.g., density, melt index, zero shear viscosity, molecular weight distribution, etc.). In some specific embodiments, the film comprises at least one polymer selected from the group consisting of Dow INNATE TM 、Exxon EXCEED TM or Exxon EXCEED TM Commercially available resins sold under the XP brand (e.g., Dow INNATE TM ST70 precision packaging resin, Dow INNATE TM ST50 precision packaging resin, Dow INNATE TM XUS 59910.03 and Dow INNATE TM TH60 Precision Packaging Resin (Dow Chemical Company, Midland, Michigan); EXCEED TM XP 6026 series, EXCEED TM XP 6056ML, EXCEED TM XP 8318ML, EXCEED TM XP8358 series, EXCEED TM XP 8656MK、EXCEED TM XP 8656ML, EXCEED TM XP 8784 series, EXCEED TM1012HJ, EXCEED TM 1012MA, EXCEED TM 1012MJ, EXCEED TM 1012MK, EXCEED TM 1015 series, EXCEED TM 1018 series, EXCEED TM 1018MA、EXCEED TM 1023MJ, EXCEED TM 1327MA, EXCEED TM 1518MA、EXCEED TM 1518MM and EXCEED TM 2012 Series (ExxonMobil Chemical Company, Houston, Texas). In some embodiments, the film comprises an ethylene / alpha-olefin copolymer composition as disclosed in U.S. Patent No. 9,115,275, which is incorporated herein by reference. Improved results are described in the illustrative examples of exemplary aspects and embodiments disclosed below and provided throughout the disclosure. Some non-limiting examples of the above resins are listed in Table 1 below to provide some additional details about some physical properties of those non-limiting resins.

[0073] Table 1: Properties of several non-limiting resins

[0074]

[0075]

[0076] Membrane structure and composition

[0077] Barrier film core layer

[0078] The barrier coextruded multilayer (B-CEML) film comprises at least one core layer adjacent to a first at least one insert layer on one side and adjacent to a second at least one insert layer on the other side. At least, at least one layer of the core layer comprises EVOH such that the total thickness of all layers comprising EVOH is less than about 5% or about 10% of the total thickness of the B-CEML, or about 5% of the combined B-CEML and NB-CEML. In some embodiments, the thickness of the barrier core layer may comprise about 0.1-5% of the total thickness of the barrier multilayer film. If no insert layers are used in the multilayer film, the core layer is adjacent to a sealant layer on either side thereof.

[0079] In an embodiment, the core layer comprises a single layer, but in alternative embodiments, it may also comprise a multilayer construction, each layer having an EVOH polymer blend that is the same or similar to that described herein. The thickness of the barrier core layer may account for about 0.1-10% of the total thickness of the barrier multilayer film. In some embodiments, the thickness of the barrier core layer may account for no more than about 5% of the total thickness of the barrier multilayer film. In some other embodiments, the thickness of the barrier core layer may account for about 0.1-5% of the total thickness of the combined non-barrier and barrier multilayer films (e.g., EVOH accounts for less than 5.0% of the combined barrier and non-barrier layer sheets of the flexible bag according to the present disclosure). Therefore, the core barrier layer comprises EVOH, so that in some embodiments, the combined thickness of one or more core barrier layers comprising EVOH is less than 5% of the thickness of the B-CEML film and / or the combined two layers of NB-CEML and B-CEML films. Thus, in some embodiments, and in particular embodiments involving flexible bags, the combined thickness of the EVOH layers, whether in the B-CEML or in the bag comprising the B-CEML and NB-CEML plies, as a percentage of the total film thickness (or weight %) is less than any of the following values: 5.0, 4.9, 4.8, 4.7, 4.6, 4.5, 4.4, 4.3, 4.2, 4.1, 4.0, 3.9, 5.8, 6.9, 7.10, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8.10, 8.2, 8.4, 8.6, 8.7, 8.8, 8.9, 9.10, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, 10. , 3.8, 3.7, 3.6, 3.5, 3.4, 3.3, 3.2, 3.1, 3.0, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2.0, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, and 0.1. In an embodiment, the combined thickness of the EVOH layers as a percentage of the total B-CEML thickness is less than a number within the range (including endpoints) defined by any two of the above numbers. In another embodiment, the combined thickness of the EVOH layers as a percentage of the total B-CEML or combined B-CEML / NB-CEML thickness is less than a number within the range (including endpoints) defined by any two of the above numbers (e.g., EVOH accounts for less than 5.0% of the combined barrier and non-barrier layers of the bag).

[0080] In an embodiment, the ethylene mole percentage in the EVOH copolymer is greater than 35%. In one embodiment, the ethylene mole percentage in the EVOH copolymer is in the range of 38% to 55%. Therefore, the ethylene mole percentage in the EVOH copolymer provided by the embodiment is selected from the following group of numbers: 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54 and 55.

[0081] In one embodiment, the barrier layer sheet of the film disclosed herein comprises a coextruded multilayer (CEML) film structure comprising an outer seal layer, a barrier core layer, and an inner seal layer. In an embodiment, the multilayer film constituting one layer within the barrier core layer comprises EVOH containing 44 mol% ethylene, wherein the maximum thickness of the EVOH accounts for 5% of the total multilayer film thickness.

[0082] In one embodiment, if the total combined thickness of EVOH is equal to or less than 5% of the total structure thickness, the EVOH can be a single core layer in a symmetrical or asymmetrical structure, or multiple layers or microlayers in a multilayer structure. Multilayer and multimicrolayer technology is available to those skilled in the art and is incorporated herein by reference (see, for example, US 5,094,793, US PGPUB 20100215879, US PGPUB 20140044906, US PGPUB 20180215121, US PGPUB 20170197348, US PGPUB 20140044906, US PGPUB 20120077005, which are incorporated herein by reference in their entirety).

[0083] In an embodiment, the EVOH has a 44 mol % ethylene content (e.g., EVALCA EVAL TM E grade). In other embodiments, other low oxygen barrier EVOH grades may be included, such as 38 mol % and 48 mol % ethylene varieties.

[0084] Outer sealing layer and inner sealing layer (OSL, ISL)

[0085] In an exemplary embodiment, the present disclosure provides a multilayer film (e.g., B-CEML and NB-CEML) comprising at least one outer sealing layer and at least one inner sealing layer. The outer sealing layer of the film is identified as being toward the outside of the film (i.e., furthest from the inner side / product contact side of the film), while the inner sealing layer is also the outer layer of the multilayer film, closest to the inner side of the package (i.e., contacting the product). The thickness of the outer sealing layer and the inner sealing layer can be the same, but in some embodiments, the outer sealing layer and the inner sealing layer can have different thicknesses. In embodiments, the outer sealing layer or the inner sealing layer can include more than one layer of film, such as 2, 3, 4 or more layers (e.g., up to about 50 layers) of film.

[0086] In an embodiment, the sealing layer may comprise about 10-100% by weight of an ethylene / α-olefin copolymer or a combination thereof, such as those described throughout the disclosure, and may contain up to 100% by weight of an ultra-low density polyethylene (ULDPE) or a linear low density polyethylene (LLDPE) polymer, in some embodiments comprising an ethylene / α-olefin copolymer, wherein the α-olefin chain may be 4 or more carbons (e.g., butene-1) or 6 or more carbons (e.g., hexene-1) or 8 or more carbons (e.g., octene-1) or a combination thereof, with a density of about 0.910 to 0.914 g / cm 3 In the range of , the melt index is about 0.7 to 1.0 dg / min. In some embodiments, the sealing layer may include a certain amount (e.g., about 5-50%) of linear low density polyethylene (LLDPE), which in some specific embodiments includes ethylene / hexene-1 or ethylene / octene-1 copolymer or a combination thereof, with a density of about 0.915 to 0.925 g / cm 3 In the range of , the melt index is about 0.7 to 1.0 dg / min.

[0087] In some embodiments, the copolymer constituting the sealing layer may include about 75-90% by weight of ultra-low density polyethylene (ULDPE) having a density of about 0.911 to 0.913 g / cm 3 , a melt index of about 0.8 to 0.9 dg / min; and 10-25 wt% by weight of a linear low density polyethylene (LLDPE), which may contain an ethylene / α-olefin copolymer (e.g., ethylene / octene-1 and / or ethylene / hexane-1) having a density of about 0.918 to 0.922 g / cm 3 In the range of , the melt index is about 0.8 to 0.9 dg / min. In some embodiments, the density of the sealing layer copolymer can be about 0.910 to about 0.925 g / cm 3 (e.g. 0.917 g / cm 3 、0.915g / cm 3 , 0.912g / cm 3 The melt index is about 0.7 to 1.0 dg / min (e.g., 0.9, 0.8 dg / min, etc.). In an embodiment, the density range can also be defined by any two of the following values ​​(in g / cm 3 denoted by ), including endpoints: 0.910, 0.911, 0.912, 0.913, 0.914, 0.915, 0.916 and 0.917 g / cm 3 .

[0088] In some exemplary embodiments, the thickness of each sealing layer accounts for about 1% to about 25% of the total thickness of the CEML film. In other words, the thickness (or weight) of each of the inner and outer sealing layers expressed as a percentage of the total thickness (or weight) of the CEML film can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24% and 25%.

[0089] In some embodiments, the thickness of the sealing layer is within the range defined by any two numbers given above, including endpoints. The thickness of the sealing layer can also be an intermediate percentage between the above percentages, such as about 11.1%, 11.2%, 11.3%, 11.4%, etc. (e.g., between the above 11% and 12%).

[0090] Insertion layer

[0091] According to the exemplary embodiments described herein, the film includes one or more inserted layers, which may contain the same or similar polymer materials in the same or similar ratios as the above-mentioned sealing layer, and may also contain other polymer components and additives. For example, the density and melt index vary within the above-mentioned ranges, the polymer components may have different ratios, and adhesives and bonding materials may be added to help form the film.

[0092] According to the exemplary aspects and embodiments described herein, the film may include multiple insert layers (e.g., second, third, fourth, fifth, etc. inner insert layers and outer insert layers). Generally, any layer not disclosed or described as a core layer or a sealing layer is characterized as an "insertion layer", and in embodiments including more than one insert layer, the insert layer adjacent to the sealing layer is identified as the "first" inner / outer insert layer, and subsequent insert layers are identified as second, third, fourth, because they are closer to the inner core of the film.

[0093] Although the barrier or non-barrier coextruded multilayer (NB-CEML) films disclosed herein may include an intervening layer adjacent to the seal layer and adjacent to the core layer, the term is intended to be used in accordance with the present disclosure to refer to a polymer or copolymer layer located between the seal layer and the core layer or between two or more core layers in B-CEML and NB-CEML films (i.e., for example, some core layers in NB-CEML may not include a barrier layer such as EVOH). Thus, in some embodiments, either or both of the NB-CEML or B-CEML may include a first intervening layer and / or a second intervening layer, such that, for example, the multilayer film may have one or more intervening layers located between the seal layer and the core / core barrier layer and / or two or more core / core barrier layers. In some embodiments, as described for the seal layer and the core layer, the intervening layer may include multiple individual layers (e.g., up to about 45 or 50 layers) that together form the first (or second or more) intervening layer.

[0094] Thus, in some embodiments, the intercalation layer may comprise ethylene / α-olefin copolymers according to those described throughout the disclosure. In some embodiments, the copolymer may comprise ethylene / α-olefin copolymers or combinations thereof (based on α-olefins with carbon chain lengths of 4, 6, or 8 or more), with a density (or density when combined) of about 0.910 to about 0.925 g / cm 3 (e.g. 0.917 g / cm 3 、0.915g / cm 3 , 0.912g / cm 3 The melt index is about 0.2-2.0 dg / min or about 0.5-1.0 dg / min, or about 0.7 to 1.0 dg / min (e.g., 0.9, 0.8 dg / min, etc.). In an embodiment, the density range can also be defined by any two numbers mentioned below (in g / cm 3 denoted by ), including endpoints: 0.910, 0.911, 0.912, 0.913, 0.914, 0.915, 0.916 and 0.917 g / cm 3 Similarly, the melt index range can be defined by any two of the above numbers, in dg / min, inclusive, and in some specific embodiments can be 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0 dg / min. In some embodiments, the total thickness of each intervening layer can be in the range of about 1% to about 40% of the total film thickness.

[0095] In some embodiments, the insert layer includes a certain amount of agents that promote the insertion layer to be combined and bonded with the core barrier EVOH layer and optionally with other insert layers and / or sealing layers, such as adhesive materials (e.g., adhesive resins or adhesives). Any known adhesive resins and adhesives can be used for the insert layer, including, for example, polyethylene copolymers of polar and non-polar repeating units with or without functional reactive groups. Modifiers can be added to further improve certain physical properties, such as the peel strength of such binders, adhesives and adhesive resins. Some non-limiting examples of adhesive resins include non-reactive adhesive resins, such as ethylene vinyl acetate (EVA), ethylene methyl acrylate (EMA), acid-modified olefin copolymers (e.g., ethylene acrylic acid (EAA) and ethylene methacrylic acid (EMAA)), and reactive adhesive resins, such as anhydride-modified polyethylene (i.e., ethylene grafted maleic anhydride (AMP)).

[0096] Non-barrier film core layer

[0097] The non-barrier coextruded multilayer (NB-CEML) film may include a core layer adjacent to an inner seal layer and an outer seal layer or insert layer, typically located within the film layer structure. In embodiments where the NB-CEML includes an insert layer in the multilayer film, the core layer is adjacent to the insert layer on either side thereof. In embodiments, the core layer may comprise the following polymer or polymer blend: 0-100% by weight, about 30-70% by weight, or about 30-50% by weight of a linear low density polyethylene (LLDPE) of an ethylene / octene-1 copolymer, with a density of about 0.910 to 0.920 g / cm 3 , the melt index is about 0.8 to 1.2 dg / min. In an embodiment, the core layer may also include 0-100% by weight of a linear low-density polyethylene (LLDPE) of an ethylene / butene-1 copolymer or a low-density ethylene / hexene-1 copolymer, with a density of about 0.918 to 0.930 g / cm 3 , a melt index of about 0.8 to 1.2 dg / min, or about 70-30% by weight or 50-70% by weight of the copolymer.

[0098] In other embodiments, the core layer comprises a polymer blend of: 35-45% by weight of ethylene / octene-1 copolymer linear low density polyethylene (LLDPE) having a density of about 0.914 to 0.918 g / cm 3 , a melt index of about 0.9 to 1.1 dg / min; and 55-65% by weight of an ethylene / butene-1 copolymer linear low density polyethylene (LLDPE) having a density of about 0.918 to 0.920 g / cm 3 , the melt index is about 0.9 to 1.1 dg / min.

[0099] Depending on the product and product storage, transportation and use conditions, the NB-CEML core layer may contain up to 100% by weight of those ethylene / α-olefin copolymers described throughout the disclosure. Depending on the desired or required properties of the NB-CEML film, the percentage of copolymer may vary from 5, 10, 20, 30, 40, 50, 60, 70, 80 and 90% and any amount in between. In embodiments, the core layer may be a single layer, but may also include a multilayer structure, each layer having the same or similar polymer blend within the above ranges. The thickness of the NB-CEML core layer may account for about 30-50% of the total thickness of the multilayer NB-CEML film.

[0100] use

[0101] In an embodiment, the present disclosure provides a flexible liquid packaging bag comprising two or more layers, wherein at least one layer comprises a barrier layer (B-CEML film) and at least one layer comprises a non-barrier layer (NB-CEML film) according to the above aspects and embodiments. Thus, the barrier layer comprises a B-CEML film structure comprising EVOH accounting for 5% or less of the total thickness of the layer or combined B / NB layer. According to such embodiments, the flexible bag does not include (i.e., does not include or consist of) nylon, polyester, or metal such as a vacuum deposited metal coating or aluminum foil. In an embodiment, the outer layer of the bag comprises a B-CEML film structure containing EVOH according to the present disclosure, and the inner layer of the bag may include a non-barrier film without EVOH. In some other embodiments, the non-barrier inner layer of the bag is thicker than the barrier outer layer, and the ratio is in the range of about 1.1:1 to about 3:1, including any ratio within this range (e.g., 3.8 mils: 1.8 mils). In such embodiments, the thickness of the inner layer can result in better self-emptying efficiency of the contents in the flexible bag.

[0102] In one embodiment, one or more barrier layers containing EVOH can form one or more outer layers of a flexible bag (e.g., outer and middle layers of a multilayer bag), and a non-barrier layer can form an inner layer of the bag. Alternatively, a barrier layer can be placed as an inner layer of the bag.

[0103] In embodiments, bag sizes may range from 0.5 US gallons to 10 US gallons (e.g., about 1, 2, 3, 4, 5, or 6 gallons). In some embodiments, sizes may also extend to bulk bags in the 10-45 and 45-400 gallon size ranges (i.e., bags may span a large size range of about 0.5 US gallons to about 400 US gallons). In some embodiments, bags may include multiple plies (i.e., there may be more than two plies in a bag). For example, such embodiments may include a combination of two barrier plies and one non-barrier ply or one barrier ply and two non-barrier plies arranged in different configurations. In accordance with the above aspects and embodiments, the thickness of the barrier layer sheet containing EVOH in such bags can vary from 1 mil to 10 mils, and in some specific embodiments can be about 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9 or 5.0 mils (where 1 mil is equal to about 25 mm). In embodiments, the thickness of the non-barrier layer can be approximately the same thickness as the above-described barrier layer (e.g., in a thickness range of 1.5 mils to 5.0 mils, 2.5 mils to 5.0 mils, 1.5 mils and 4.0 mils, and similar ranges within the above-described general ranges). In other embodiments, the thickness of the non-barrier layer is greater than the above-described thickness of the above-described barrier layer.

[0104] In some embodiments, the flexible bag is used to package concentrated soft drink syrups (e.g., beverage bags). In some embodiments, the flexible bag is used to package edible oils. In some embodiments, the flexible bag is used to package liquid dairy products (ambient or refrigerated conditions). In some embodiments, the flexible bag is used to package non-food, industrial fluids or chemicals. In some embodiments, the flexible bag contains a coloring layer to provide color (white, blue, black, etc.).

[0105] In an embodiment, the maximum amount of EVOH contained in the bag in the complete bag structure does not exceed 5.0%, 4.5%, 4.0%, 3.5%, 3.0% or 2.5% of the total thickness or weight of the film structure. In an embodiment including a barrier and non-barrier layer structure, the total amount of EVOH (thickness or weight percentage) in the entire layer structure is reduced because the non-barrier film layer does not contain EVOH. In an embodiment involving a bag structure, nylon is not included, PET is not included, and metallization is not included. In some embodiments, the bag does not include any thermal laminate or adhesive laminate. In some embodiments, the bag is made for packaging liquids such as concentrated beverage syrups, edible oils, and industrial liquids such as soaps, detergents, etc. at ambient temperatures. As described herein, flexible bags according to the present disclosure can be used to distribute and dispense viscous liquids, such as food (e.g., premixed syrups for preparing beverages). The bag typically includes a thin, flexible plastic wall, sealed at the edges, and has a dispensing spout or fitting sealed to the bag wall. See, for example FIG. 4A to FIG. 4B . FIG. 4A to FIG. 4B The general depiction of the bag in the Figures is merely illustrative of non-limiting embodiments of the present disclosure. As described herein, the flexible bag can be designed and manufactured to many specifications (e.g., including more than one fitting in different locations, different bag shapes, varying amounts of any one or more bag corners, hanging holes, and other structures generally known in the art).

[0106] In use, the flexible bag is filled with a flowable material to be dispensed, and the bag may be packaged in a relatively rigid container, such as a corrugated cardboard box, for dispensing (e.g., a "bag in a box"). Typically, in use, a spout or fitting on the flexible bag is adapted to cooperate with a dispensing tap or a service line connector to control and direct the dispensing of the bag contents. Because the bag walls are thin and flexible, conventional bags may collapse when the contents are removed. The problem with the prior art solved by the flexible bag according to aspects and embodiments of the present disclosure is that when the liquid contents of the bag are dispensed, it is possible that one of the flexible bag walls may be sucked close to the spout even if a significant proportion of the contents remain in the bag. The bag wall may cover the inner end of the spout, thereby blocking it and cutting off the flow of the contents. Due to the pressure of the remaining liquid in the bag on the wall, it is difficult and cumbersome to remove the wall from the spout and clear the obstruction. This is typically solved in the art by incorporating one or more emptying aids, which are designed and adapted to maintain flow by preventing obstructions caused by bag collapse.

[0107] In some embodiments, the flexible bag according to the present disclosure can maintain the flow and output of the bag contents without the need for dispensing aids such as emptying channels, tubes, forms, dip strips, or reinforced / embossed films known in the art that may help ensure that the bag contents are completely emptied. Unexpectedly, the inner and outer sheets of the bags disclosed herein are structured while exhibiting improved toughness to provide sufficient rigidity for the bag geometry and allow its flowable contents to be completely self-emptied. That is, it was unexpectedly observed that even when the bag is completely or substantially completely emptied of its contents, the flowable contents within the flexible bag of the present disclosure reach and flow to and through the mouth without the need for any additional emptying aids.

[0108] Thus, the flexible bags are convenient because they can be made relatively flat in the unfilled state, thus facilitating storage and transport to the location where they are to be filled (the bag geometry is not distorted by the incorporation of the emptying aid). Furthermore, the bag according to the exemplary embodiment of the present disclosure does not require any device to be inserted into the bag after it is formed, thereby reducing manufacturing costs.

[0109] In addition, bags according to exemplary embodiments of the present disclosure are well suited for use with service line connectors provided with quick disconnect fittings and valves. Such quick disconnect fittings and valves may use a valve element that slides within the fitting or spout, protrudes into the bag when activated by inserting the service line connector, and withdraws into the fitting to shut off the flow of contents when the connector is withdrawn. In such applications, the bag of the present invention avoids any possible interference between the slide of such a valve and an emptying channel or structure that would be attached to or around the spout.

[0110] In use, bags according to exemplary embodiments of the present disclosure are capable of achieving self-emptying of flowable material / contents to levels that meet industry requirements (i.e., emptying more than 95% of the contents (95%, 96%, 97%, 98%, 99%, 99.5%, 99.6%, 99.7%, 99.8%, or 99.9%)) without the need for an emptying aid. This level of emptying observed without the need or assistance of incorporating an emptying structure is unexpected, and the flexible bags described herein provide substantial advantages over the state of the art. In use, the observed excellent levels of content emptying can be achieved in a variety of flexible bag or bag-in-box orientations, such as arrangements with the dispensing spout facing the bottom surface as well as facing the side.

[0111] additive

[0112] In some embodiments, the film may include standard additives commonly known and used in the art, such as antioxidants, stabilizers, antiblocking agents and slippery additives. Optionally, any one or more of the sealant or insert layer may include one or more additives that may contribute to film processing in the bag making process, such as polymer processing aid concentrates and / or slippery / antiblocking concentrates. Any of such additives commonly known and used in the art may be used, including additives of the following types.

[0113] Slip Agent

[0114] Any slip agent known in the art can be included in the film layer, usually in the range of about 200 to 2000ppm or 0.5-2.5% of the weight of a particular layer. In some embodiments, if the addition of the antiblocking agent provides certain functions provided by adding one or more slip agents, the addition of the slip agent can be less than about 200ppm (even without, i.e. 0ppm). The non-limiting example of a slip agent is erucic acid amide or other fatty acid amides, such as oleamide. The slip agent can reduce the friction coefficient of the film and make it easy to slide on various surfaces.

[0115] Anti-adhesion agent

[0116] Any film anti-blocking agent known in the art can be added to the film layer, usually in the range of about 1000-5000ppm or 0.5-2.5% of the weight of the sealing layer or interlayer. However, in some embodiments, the amount of the anti-blocking agent can be increased to about 10,000ppm without any negative impact on the properties and performance characteristics of the film. For example, typical anti-blocking agents such as diatomaceous earth, synthetic silica or talc can be added to the inner and outer sealing layers of the film. Anti-blocking materials may help reduce the coefficient of friction between the film and the metal surface on which the film is drawn during the bag making process.

[0117] Processing Aids

[0118] Any processing aid known in the art may be added to the outer and inner sealing layers of the film, such as the non-limiting example of fluoroelastomer-based polymers.

[0119] The films disclosed herein can be used to make a variety of articles, including flexible bags containing flowable materials, which are made from the aforementioned multilayer films in tubular form and have transverse heat-sealed ends.

[0120] In some embodiments, the present disclosure provides a method for making a pouch filled with a flowable material using a conventional bag making process described herein. The pouches can be made using a vertical form fill and seal ("VFFS") apparatus, wherein each pouch is made from a flat film web as follows: a tubular film is formed from the flat film web with a longitudinal seal, the tubular film is then flattened at a first position and heat sealed transversely at the flattened position, the tubular film is filled with a predetermined amount of flowable material above the first position, the tubular film is flattened at a second position above the predetermined amount of flowable material and heat sealed transversely at the second position, the improvement comprising making the pouch from a flat film web made from the aforementioned multilayer film. U.S. Patents Nos. 5,538,590, 9,327,856, and 9,440,757 describe VFFS processes and modifications thereof, and are incorporated herein by reference in their entirety.

[0121] Although various aspects and embodiments describe melt index ranges, it should be understood that the melt index of the polymer is a typical melt index of a film grade polymer that can be used. The multilayer films of the present invention are capable of forming lap seals as well as wing seals. They also significantly reduce curling in laminated materials.

[0122] One film manufacturing method is the so-called blown film process. After manufacturing the film is cut lengthwise to the appropriate width. Multilayer film manufacturing methods are by using a blown film coextrusion process, but other film manufacturing methods may be used.

[0123] Ply sheets in flexible bags and bulk bags

[0124] As discussed herein, the present disclosure provides bags incorporating an EVOH barrier layer in a polyolefin film, resulting in bags having sufficient flex crack resistance, sufficient toughness, and sufficient barrier properties for short shelf life flowable materials, but recyclable because they do not contain any nylon or PET or metallized versions thereof. In specific embodiments, flexible packaging constructed from the films disclosed herein can have a wide range of sizes, from pouches (e.g., 100 mL-2,500 mL), pouches (e.g., 1-6 USG), or bulk bags (e.g., 50-400 USG), bags containing NB-CEML and B-CEML films are used to package liquids, including, for example, dairy products, milkshakes, candy, chili, coffee, vegetable and juices, sauces, and purees. It was found that including a small amount of EVOH (less than 5% of the film thickness or less than 5% of the film weight) unexpectedly resulted in improved flex crack resistance, improved toughness, and improved barrier properties relative to baseline measurements. This also provides the option of eliminating the use of materials such as nylon, PET or metallized versions thereof to obtain barrier properties which would otherwise render the film and bags formed therefrom non-recyclable.

[0125] In an embodiment, the flexible bag does not have any liner, thereby providing an unlined bag which may be a single layer or multilayer bag but without a liner. In an embodiment, a thermally laminated polymer film structure comprising a B-CEML type film disclosed herein is fabricated.

[0126] Bags that can be made from B-CEML / NB-CEML films can be pre-made and then filled with food via the fittings. They are typically sterilized and can be irradiated, for example, in a batch process using standard radiation conditions known in the art. It is also possible to sterilize the film instead of the bag. Sterilization can be achieved in a variety of known ways, such as by exposing the film or bag to a hydrogen peroxide solution. The film used to make the pouch can be treated in a similar manner before the package is formed.

[0127] Bag Making

[0128] In one aspect, bags may be made by a method comprising the steps of providing one or more films as described herein, including a barrier CEML film, securing a nozzle to the inner and outer plies of the film structure through holes provided therein, sealing the plies together transversely across the width of the film structure to form a top seal for one bag and a bottom seal for the bag and a top seal for an adjacent bag, then applying the plies together parallel to the length of the bag production line to either side of the polymer film, removing entrapped air before completely sealing the bag, and separating the bags immediately or prior to use. Typical bag making processes are generally described in U.S. Patent No. 8,211,533, which is incorporated herein by reference. In some embodiments, a method of making bags that can be filled with a flowable material may include using a bag production line, wherein each bag is made from a flat film web, the method may include the steps of:

[0129] (I) The film is unrolled by two upper rollers and two lower rollers.

[0130] (II) Each bag is inkjet code marked.

[0131] (III) Punch a nozzle hole in each bag.

[0132] (IV) Insert the mouth into the bag.

[0133] (V) Brush bag to remove entrained air.

[0134] (VI) A transverse seal is formed at the bottom of one bag and the top of the next bag.

[0135] (VII) Formation of a long seal.

[0136] (VIII) The bag is pulled through the production line using a servo drive.

[0137] (IX) Perforations are formed between adjacent transverse seals.

[0138] (X) The bag is pushed to the end of the production line via a conveyor belt.

[0139] (XI) Pack the bags into boxes.

[0140] The above steps are typical steps of a bag making machine. It should be noted that the order of steps may vary depending on the bag making machine.

[0141] The following examples will help to further illustrate and clarify the present disclosure and the above-mentioned aspects and embodiments.

[0142] Example

[0143] Example 1: Coextrusion of multilayer films and bags containing the films

[0144] The embodiment details array experiments of preparing multilayer films using film extrusion processes generally known and used in the film manufacturing industry. The film can be extruded on a conventional extrusion line of a multilayer film such as a three-layer, five-layer, seven-layer, nine-layer or even more-layer blown film coextrusion line. Films based on resin combinations according to aspects and embodiments of the present disclosure can also be manufactured using other film extrusion processes known and used in the film manufacturing industry.

[0145] Non-limiting exemplary operating conditions for preparing multilayer films may include those in Table 2:

[0146] Table 2: Coextrusion of multilayer films - conditions

[0147] parameter Quantity Production line throughput 350 lbs / h (160K / h) Blowing ratio 2.5 Lay flat 38.65 inches (97.80 cm) Double winding rollers (2 on top) 16.75" (42.54cm) Width OD (outer diameter) of each roller 9.5" (24cm), except one set of rollers which are 8.25" (21cm) OD Die size 250mm Die gap 2 mil (51 mm) Air Ring and IBC Cooling 50℉, air cooled with cold water Rotating roller gap Any Automatic instrument Control Open processor close

[0148] Film thickness may vary as described herein, but may suitably be from about 1.5 or 1.8 mils (or about 38-45 microns) to about 3.8 mils (or about 96.5 microns).

[0149] Test bags (e.g., 5 gallon bags) are prepared using the films at typical production rates (e.g., a rate of 25 bags / minute). For example, the edges of the bags are heat sealed together using conventional techniques (e.g., heat sealing, e.g., using a Maverick bag production line, or impulse sealing, etc.) to form a two-layer bag. Typical dimensions for a 5 gallon bag may be about 18.75 inches in outer width and 24.75 inches in outer length. An opening with a mouth and a lid may be formed in the bag.

[0150] The films were formed using typical extrusion conditions as described or known in the art.The barrier CEML included an EVOH layer within its core layer stack and was used to provide exemplary embodiments of the present disclosure.

[0151] Bruceton Stair Drop Test (ASTM D 5276 A 2.4.2 version)

[0152] The Bruceton stair drop test is performed to evaluate bag strength / resilience. Typically, the test includes a group (e.g., about 30) of bags. The first bag is positioned so that the longitudinal axis of the bag coincides with an imaginary horizontal line, the bottom of the bag is at a suitable initial drop height (e.g., 8 feet), and the vertical seal faces upward. In this orientation, the bag is dropped onto a stainless steel plate and then inspected visually and tactilely for damage or leaks. Depending on the intended use of the bag, the test can be performed by maintaining a constant or consistent bag temperature (e.g., about 4°C, ambient temperature, or 40°C) between tests.

[0153] If the first bag passes the drop test intact and leaks nothing, a new bag is selected and dropped from a height that is increased by 1 foot, such as 9 feet. Alternatively, if the first bag leaks, a new bag is selected and dropped from a possible lower height (e.g., 7 feet). Testing continues, with new bags used for each drop, until at least 5 passes and 5 failures occur within the range of heights where both passes and failures occur. The 50% failure height is then calculated using the statistical method of ASTM 1 D 5628. Certain drop tests provided below were performed as follows: The flexible bag was filled to a total weight of approximately 41.6 pounds (19 kg). The bag was dropped horizontally with the fittings upward. The temperature of the water in the bag was recorded. For each test, 30 bags were dropped. The F-50 value is the median bag drop height in feet. During the Bruceton drop, the water temperature filling the five-gallon bag was 60-65°F (15-18°C).

[0154] Flex crack resistance

[0155] The Gelbo flex test was used to determine the flex crack resistance of films used to prepare the flexible bags of the present invention and for comparison or benchmark or control samples. The test is described below. It was observed that the films according to aspects and embodiments of the present disclosure unexpectedly improved flex crack resistance relative to the comparative embodiment films. The comparative films are also alternatively referred to as "control" or "reference" films or embodiments.

[0156] This test determines the resistance of flexible packaging materials and films to pinhole failure caused by flexing. However, it does not measure any wear characteristics related to flex failure. The colored turpentine portion of the test measures failures characterized by physical holes that completely penetrate the structure.

[0157] The Gelbo flex tester is set to test according to ASTM F-392. The equipment basically consists of a 3.5-inch (90mm) diameter fixed mandrel and a 3.5-inch diameter movable mandrel that are face-to-face and 7 inches (180mm) apart (i.e., maximum distance) at the start position of the stroke. The two sides of the film sample are taped around the circular mandrel, thereby forming a hollow cylinder between them. The movement of the movable mandrel is controlled by a slotted shaft attached to the movable mandrel. The shaft performs a 440-degree torsional movement while moving itself toward the fixed mandrel, thereby wrinkling the film so that the mandrels facing each other are finally only 1 inch apart at their minimum distance. The machine reciprocates, and the forward and return strokes complete a complete cycle. The machine runs at 45 cycles / minute.

[0158] In this tester, samples of flexible materials are flexed under standard atmospheric conditions (23°C and 50% relative humidity) unless otherwise specified. The number of flexing cycles can vary depending on the flex crack resistance of the film structure being tested. The flexing action produced by this machine consists of a twisting motion, which repeatedly twists and wrinkles the film. Flex crack failure is determined by measuring the pinholes formed in the film. The flex crack failure is determined by twisting one side of the film sample being tested (area 300 cm 2 ) is applied with colored turpentine and stained through the hole onto white backing paper or blotting paper to determine pinholes. Pinhole formation is a standard criterion for measuring failure, but other tests such as gas transmission rate can be used instead of or in addition to the pinhole test. The reported results are the average of four replicates.

[0159] Gelbo flex data is provided below and was generated at a much higher number of flex cycles than recommended in the ASTM method (10,800 cycles versus the normal 2,700 cycles for coextruded films). The difference between the two samples was tested using a higher number of cycles (i.e., 10,800 cycles) because this provides a better correlation to what is happening in the field.

[0160] Oxygen Transmission Rate

[0161] The OTR test determines the oxygen transmission rate reduction of films used to make flexible bags of the present invention. The test is described as follows.

[0162] The MOCON template for the Mocon Oxtran machine is used to cut the appropriate size film sample on the cutting mat. The cut sample film is then placed in the Mocon Oxtran and clamped in place according to the specific machine requirements. The machine is set up according to ASTM D3985 standards. The parameter settings are based on industry standard testing. The test temperature is set to 23°C and 60% RH. The samples are tested until a plateau is shown in the graph, and the test time varies from 8 hours to 70 hours depending on the curve in the graph. All results are in cm 3 / 100in 2 -Record in days.

[0163] The pocket formed by the NB-CEML inner sheet and the B-CEML outer sheet

[0164] Implementation Method 1 .

[0165] Flexible bags according to aspects and exemplary embodiments of the present disclosure were prepared for testing using a two-layer structure in a five-gallon size. The outer layer of the flexible bag included the following structure: 3.8 mils (96.5 microns) thick; symmetrical; coextruded; a seven-layer film, with an EVOH (44 mol% ethylene) layer as a barrier core layer (approximately 3.0-4.8 microns, determined to be 3.3 microns in some exemplary measurements) accounting for 2.5-5.0% of the barrier film thickness. Thus, the EVOH layer accounts for about 3.4% (3.4 when using the measured 3.3 microns) and less than 5% of the total thickness of the outer barrier layer. The inner layer of the flexible bag includes the following structure: 1.5 mils (38 microns) thick; symmetrical; coextruded; a five-layer film, the core layer does not contain any EVOH. Tables 3 and 4 provide a general overview of the layer structures that can be used according to aspects and embodiments of the present disclosure and illustrative exemplary embodiments.

[0166] Table 3: Overview of barrier outer layer

[0167]

[0168] Table 4: Overview of non-barrier inner layer sheets

[0169]

[0170]

[0171] Reference Implementation .

[0172] A comparative flexible bag having a two-layer sheet structure was prepared, wherein the outer barrier layer sheet had the following structure: 3.8 mil (96.5 microns) thick; symmetrical; coextruded; seven-layer film, with an EVOH (32 mol % ethylene) layer as a barrier core layer accounting for 2.5-5.0% of the barrier film thickness (approximately 3.0-4.8 microns in some measurements). Thus, the EVOH layer accounted for about 2.5-5.0% of the total outer layer sheet thickness (e.g., 3.6 μm / 96 μm).

[0173] The inner sheet of the comparative flexible bag comprised the following structure: 1.5 mil (38 microns) thick; coextruded; five-layer film without any EVOH in the core layer.

[0174] The results of the Bruceton bag drop test are given below, where the goal was to achieve a 4 foot F50 (median) drop value.

[0175] Table 5: Bruceton bag drop test

[0176]

[0177] Table 5.1: Bruceton Bag Drop Test – Percent Improvement in Performance

[0178]

[0179] The flexible bag of Embodiment 1 unexpectedly exhibited a 57% and 29% improvement in Bruceton bag drop height relative to the comparative flexible bag at 15° C. and 24° C. In fact, the flexible bag of Embodiment 1 achieved the targeted 4 foot drop height.

[0180] The coextruded films of the Reference Embodiment and Embodiment 1 were compared to evaluate the flex crack resistance and stiffness of the EVOH containing outer (barrier) layer sheets and are summarized in Tables 6 to 6.1.

[0181] Table 6: Gelbo Flexural Test (ASTM F-392) and 1% Secant Modulus (ASTM D-882)

[0182]

[0183] Table 6.1: Percentage improvement in flex crack resistance and stiffness of outer (barrier) layer sheets

[0184]

[0185] The above results show that the EVOH coextruded film according to the present disclosure has good or improved Gelpo flex crack resistance compared to the reference embodiment, which may be due to the lower tensile modulus to some extent, resulting in a more flexible flexible film. For example, relative to the comparative (reference) coextruded film, the film disclosed herein can show improved flex crack resistance (e.g., about 35%) in the longitudinal direction. Similarly, in the transverse direction, the flex crack resistance of the film according to the present disclosure can be improved by about 22%. Due to the 1% secant modulus, the tensile modulus of the film according to the present disclosure is reduced by about 12% in the longitudinal direction and 15% in the transverse direction compared to the reference embodiment film. These results are not expected because the main difference between the two films is caused by the introduction of a small amount (i.e., a thin layer) of high ethylene content EVOH into the core layer of the coextruded film. The EVOH structure and content help to improve the barrier properties of the film while also making the bags or other materials made of the film easier to recycle. When the filled bags are boxed, palletized and transported to the end-user location, the improvement in flexural modulus and secant modulus also translates into excellent transportation performance.

[0186] Example 2. Flexible bag performance.

[0187] In the following examples, the thickness of the outer and inner sheets were varied to determine any effect on the drop performance of the Bruceton bag and the performance of the structure as an oxygen barrier. Oxygen barrier properties were tested using MOCON according to ASTM D3985 protocol.

[0188] Implementation Method 2 .

[0189] The outer layer sheet of the flexible bag according to embodiment 2 comprises the following structure: 3.8 mil (96.5 microns) thick; symmetrical; coextruded; seven-layer film, with an EVOH (44 mol % ethylene) layer (about 3.0-4.8 microns in some measurements) within the core layer accounting for 2.5-5.0% of the thickness of the barrier film. Thus, the EVOH layer accounts for about 2.5-5.0% of the total outer layer thickness (e.g., 3.4% (100×(3.3 μm / 96 μm)).

[0190] The inner layer of the flexible bag comprises the following structure: 1.5 mil (38 microns) thick; co-extruded, the core layer does not contain any EVOH. The percentage of the EVOH layer thickness to the total thickness of the two layers can be approximately (e.g., 2.4% (100×(3.3μm / (96μm+38μm)))).

[0191] Implementation 3 .

[0192] In Embodiment 3, the outer layer sheet of the flexible bag comprises the following structure: 3.8 mil (96.5 microns) thick; symmetrical; coextruded; seven-layer film, with an EVOH (44 mol % ethylene) layer within the core layer that accounts for 2.5-5.0% of the barrier film thickness (approximately 3.0-4.8 microns in some measurements). Thus, the EVOH layer accounts for about 2.5-5.0% of the total outer layer thickness (e.g., about 3.4% (100×(3.3 μm / 96 μm)).

[0193] The inner layer of embodiment 3 comprises the following structure: 45 micron thick; coextruded film structure without any EVOH core barrier layer. The percentage of EVOH layer thickness to the total thickness of the two layers can be approximately (e.g., 2.3% (100×(3.3μm / (96μm+45μm)))).

[0194] Implementation 4 .

[0195] The outer layer sheet of the flexible bag of embodiment 4 comprises the following structure: 70 microns thick; symmetrical; coextruded; seven layers, with an EVOH (44 mol % ethylene) layer within the core layer that accounts for 2.5-5.0% of the thickness of the barrier film (about 2.0-4.8 microns in some measurements). The EVOH layer thus accounts for about 2.5-5.0% of the total outer layer thickness (e.g., about 3.4% (100×(2.4 μm / 70 μm)).

[0196] The inner layer of embodiment 4 comprises the following structure: 70 micron thick; coextruded film structure without any EVOH core barrier layer. The percentage of EVOH layer thickness to the total thickness of the two layers can be approximated as (e.g., 1.7% (100×(2.4μm / (70μm+70μm))).

[0197] Implementation method 5 .

[0198] The outer layer sheet of the flexible bag of embodiment 5 comprises the following structure: 45 micron thick; symmetrical; coextruded; seven-layer film, with an EVOH (44 mol % ethylene) layer within the core layer that accounts for 2.5-5.0% of the thickness of the barrier film (about 1.5-4.8 microns in some measurements). The EVOH layer thus accounts for about 2.5-5.0% of the total outer layer thickness (e.g., about 3.5% (100×(1.6μm / 45μm)).

[0199] The inner layer of embodiment 5 comprises the following structure: 96 micron thick; co-extruded film structure, the core layer does not contain any EVOH. The percentage of EVOH layer thickness to the total thickness of the two layers can be approximately (e.g., 1.1% (100×(1.6μm / (45μm+96μm)))).

[0200] Implementation 6 (Comparison / Reference) .

[0201] The outer sheet in the flexible bag of embodiment 6 comprises the following structure: 96 microns thick; symmetrical; coextruded; seven-layer film, with an EVOH (32 mol % ethylene) layer within the core layer that accounts for 2.5-5.0% of the barrier film thickness (about 3.0-4.8 microns in some measurements). The EVOH layer thus accounts for about 2.5-5.0% of the total outer sheet thickness (e.g., about 3.4% (100×(3.3 μm / 96 μm)).

[0202] The inner layer of the flexible bag has the following structure: 38 microns thick; coextruded film structure without any EVOH core barrier layer. The percentage of EVOH layer thickness to the total thickness of the two layers can be approximated as (e.g., 2.4% (100×(3.3μm / (96μm+38μm)))).

[0203] Implementation 7 (Comparison / Reference) .

[0204] The outer sheet of the flexible bag of embodiment 7 comprises the following structure: 96 microns thick; symmetrical; coextruded; seven-layer film, with an EVOH (32 mol % ethylene) layer within the core layer that accounts for 2.5-5.0% of the thickness of the barrier film (about 3.0-4.8 microns in some measurements). The EVOH layer thus accounts for about 2.5-5.0% of the total outer sheet thickness (e.g., about 3.4% (100×(3.3 μm / 96 μm)).

[0205] The inner layer of the flexible bag has the following structure: 45 micron thick; coextruded film structure without any EVOH core barrier layer. The percentage of EVOH layer thickness to the total thickness of the two layers can be approximated as (e.g., 2.3% (100×(3.3μm / (96μm+45μm)))).

[0206] Table 7: Bruceton bag drop and oxygen transmission rate with different outer and inner sheet thickness

[0207]

[0208] Exemplary embodiments 3, 4, and 5 show that varying the thickness of the outer and inner layers while keeping the overall thickness the same keeps the desired height of the F50 bag drop above 4.0 feet. Reducing the inner non-barrier layer from 45 microns to 38 microns (embodiments 2 and 3) keeps the drop height above 4 feet. Reducing the thickness of the outer barrier layer and increasing the thickness of the inner non-barrier layer also reduces the total amount of EVOH in the structure from 2.4% to 1.1% (excluding accessories). Therefore, depending on the maximum amount of EVOH allowed in packaging for recyclable purposes, the total amount of EVOH can be adjusted.

[0209] Comparative embodiments 6 and 7 show inferior bag drop heights of less than 4 feet. These two comparative embodiments contain a higher barrier EVOH grade (32 mol % ethylene grade) in the core layer, which can be used for some standard industrial applications. While the embodiments may exhibit better oxygen barrier performance than non-barrier films, the bag drop performance deteriorates, likely due to the physical properties of the 32 mol % ethylene grade, which is typically brittle. Thus, the addition of the oxygen barrier merely increases the manufacturing cost and unexpectedly fails to provide the resilience, recyclability, and oxygen barrier properties exhibited by the films and flexible bags of the exemplary aspects and embodiments described in the present disclosure.

[0210] The oxygen barrier of a typical bi-directional nylon laminate used in the industry for a typical beverage bag is approximately 3.6 cm 3 / 100in 2 / day. The oxygen barrier data was generated for a 3.8-mil (96-μm) thick thermal laminate with a 0.48-mil (12 μm) thick bidirectional nylon 6 core layer. The entire range of oxygen barrier values ​​for the various embodiments in the Examples were demonstrated to be superior to the benchmark bidirectional nylon value. Therefore, the use of films according to the exemplary embodiments described herein to produce flexible bags can maintain shelf life without the need for higher EVOH barrier properties (lower OTR values). This also reduces costs.

[0211] Example 3. Comparison of films and bags to standard bidirectional nylon.

[0212] Two-ply five-gallon bags were made from films having the following structure: an outer ply (1.8, 2.8, and 3.8 mils thick) having seven coextruded layers with an EVOH core (44 mol % ethylene) constituting 5% of the maximum thickness of the ply; and an inner ply (3.8, 2.8, and 1.8 mils thick) having five coextruded layers without an EVOH / barrier layer.

[0213] The five-gallon bag produced on the Maverick bag line has an outside width of 18.75" and an outside length of 24.75".

[0214] For comparison, a two-ply standard bi-directional nylon bag was produced using the following ply structure: an outer ply having a 3.8 mil bi-directional nylon laminate; and an inner ply having a 1.8 mil LLDPE.

[0215] The bags were evaluated using a drop test, where ten bags of each bag type were dropped from a height of 30 inches. The bags were filled with water on a Liqui-Box 1500 filler and stored at a constant temperature (73°F, ambient; and 40°F, cold) for 16 hours before testing. The total bag weight was approximately 43 pounds.

[0216] Each bag is dropped three times. The first drop causes the bag to drop horizontally with the accessory facing upward, the second drop causes the bag to drop horizontally with the bottom transverse seal facing upward, and the third drop causes the bag to drop vertically with the longitudinal seal facing upward.

[0217] Table 8. Drop test performance

[0218]

[0219] The drop data demonstrates that bags produced according to exemplary embodiments of the present disclosure have at least the same resilience as bags made with standard bi-directional nylon materials over a standard temperature range (ambient and cold) and with different thicknesses of barrier and non-barrier layers. This improved resilience of such bag materials is unexpected and provides at least one or more of the following features:

[0220] (a) reducing and / or limiting the amount of EVOH in the core layer of the barrier sheet to a maximum of 5% of the total film thickness, which is significantly different from most EVOH-containing film structures where the amount of EVOH in the core layer is typically between 5% and 12%, and allows for greater downstream sustainability and recyclability;

[0221] (b) low oxygen barrier grades of EVOH including, for example, ethylene contents greater than about 30 mol % and up to about 48 mol % (e.g., 44 mol %), which are significantly different from typical EVOH blown film structures using 29 mol % or 32 mol % ethylene contents and provide improved oxygen barrier properties;

[0222] (c) A film structure that allows for easy adjustment of the EVOH barrier layer thickness in the outer barrier ply, as well as the thickness of the inner non-barrier ply, to reduce the overall level of EVOH in the bag when necessary or preferred, thereby reducing the total amount of EVOH in the entire bag structure (excluding accessories) to about 2.5% and as low as 1.1% of the total ply structure thickness.

[0223] (d) The films offer improved performance and recyclability relative to other films and bag structures using materials such as nylon, PET or metals (eg, vacuum deposited coatings or aluminum foil).

[0224] Thus, embodiments disclosed herein provide low oxygen barrier films and bags for use in end-use applications (e.g., for bag-in-box) for products with a shelf life of about six months or less, including, for example, beverages and beverage-related additives (e.g., syrups), edible oils, dairy products, etc. In such embodiments, the use of the films for high-barrier bag-in-box for long-shelf-life aseptic or hot-fill packaging is generally avoided.

Claims

1. A bag for packaging a flowable material, the bag comprising a recyclable barrier coextruded multilayer polymer film and a non-barrier coextruded multilayer polymer film, wherein the barrier coextruded multilayer polymer film comprises: (i) an inner sealing layer, the inner sealing layer comprising a density of 0.894 g / cm 3 to 0.920g / cm 3 The ethylene / α-olefin copolymer fraction is present in an amount of at least about 50% by weight or thickness of the total inner sealant layer, wherein the total density of the inner sealant layer is about 0.910 g / cm 3 to 0.924g / cm 3 within the scope of (ii) a first insertion layer and a second insertion layer, which contain a density of 0.894 g / cm 3 to 0.920g / cm 3 an ethylene / α-olefin copolymer fraction in an amount within a range of about 50% by weight or thickness of the first insert layer and an adhesive or bonding resin in an amount effective to improve the bonding of the first insert layer and the second insert layer to at least one other layer of the coextruded multilayer polymer film, wherein the combined density of the first insert layer and the second insert layer is about 0.910 g / cm 3 to 0.924g / cm 3 within the scope of (iii) a core barrier layer comprising from about 0.1% to about 10% by weight or total thickness of the coextruded multilayer polymeric film, or about 5% or less by weight or thickness of the barrier and non-barrier films combined, of ethylene vinyl alcohol (EVOH) copolymer, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iv) an outer sealing layer, the outer sealing layer comprising a density of 0.894 g / cm 3 to 0.920g / cm 3 The ethylene / α-olefin copolymer fraction is present in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the outer seal layer has a total density of about 0.910 g / cm 3 to 0.924g / cm 3 within the range.

2. A bag for packaging a flowable material, the bag comprising a recyclable barrier coextruded multilayer polymer film and a non-barrier coextruded multilayer polymer film, wherein the barrier coextruded multilayer polymer film comprises: (i) an inner sealing layer, the inner sealing layer comprising a density of 0.894 g / cm 3 to 0.920g / cm 3 The ethylene / α-olefin copolymer fraction is present in an amount of at least about 50% by weight or thickness of the total inner sealant layer, wherein the total density of the inner sealant layer is about 0.910 g / cm 3 to 0.924g / cm 3 within the scope of (ii) a first outer insert layer and a second outer insert layer, and The first inner insert layer and the second inner insert layer, wherein all the insert layers contain a density of 0.894 g / cm 3 to 0.920g / cm 3 The ethylene / α-olefin copolymer fraction is present in an amount of at least about 50% by weight or thickness of the first insert layer, wherein the total density of all insert layers is about 0.910 g / cm 3 to 0.924g / cm 3 within the range wherein the first inner insert layer and the second inner insert layer comprise an amount of adhesive or adhesive resin effective to improve adhesion of the first inner insert layer and the second inner insert layer to at least one layer of the coextruded multilayer polymeric film; (iii) a core barrier layer adjacent to and between the first inner interleaf layer and the second inner interleaf layer, the core barrier layer comprising from about 0.1% to about 10% by weight or thickness of the coextruded multilayer polymeric film, or about 5% or less by weight or thickness of the barrier and non-barrier films combined, of ethylene vinyl alcohol (EVOH) copolymer, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iv) an outer sealing layer, the outer sealing layer comprising a density of 0.894 g / cm 3 to 0.920g / cm 3 The ethylene / α-olefin copolymer fraction is present in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the outer seal layer has a total density of about 0.910 g / cm 3 to 0.924g / cm 3 within the range.

3. The bag of claim 1, wherein the barrier film and the non-barrier film each have a thickness of about 1 mil to about 5 mils.

4. The bag of claim 2, wherein the barrier film and the non-barrier film each have a thickness of about 1 mil to about 5 mils. The bag of claim 1 , wherein the non-barrier film has a thickness greater than that of the barrier film.

6. The bag of claim 2, wherein the non-barrier film has a thickness greater than that of the barrier film.

7. The bag of claim 5, wherein the thickness of the non-barrier film is about 3.8 mils and the thickness of the barrier film is about 1.8 mils.

8. The bag of claim 6, wherein the thickness of the non-barrier film is about 3.8 mils and the thickness of the barrier film is about 1.8 mils.

9. The bag of claim 1 , wherein the weight percentage or thickness percentage of the EVOH layer in the barrier coextruded multilayer polymer film relative to the entire film is selected from the following values: 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9 and 5.

0.

10. The bag of claim 2, wherein the weight percentage or thickness percentage of the EVOH layer in the barrier coextruded multilayer polymer film relative to the entire film is selected from the following values: 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9 and 5.

0.

11. The bag of claim 1 , wherein the bag is configured to empty from about 95% to about 99.9% of its contents without incorporating any emptying aid.

12. The bag of claim 2, wherein the bag is configured to empty from about 95% to about 99.9% of its contents without incorporating any emptying aid.

13. A bag for packaging post-mix syrup, the bag comprising at least one screw-on fitment, a recyclable barrier coextruded multilayer polymeric film, and a non-barrier coextruded multilayer polymeric film, wherein the barrier coextruded multilayer polymeric film comprises: (i) an inner sealing layer, the inner sealing layer comprising a density of 0.894 g / cm 3 to 0.920g / cm 3 The ethylene / α-olefin copolymer fraction is present in an amount of at least about 50% by weight or thickness of the total inner sealant layer, wherein the total density of the inner sealant layer is about 0.910 g / cm 3 to 0.924g / cm 3 within the scope of (ii) a first insertion layer and a second insertion layer, wherein the insertion layer comprises a density of 0.894 g / cm 3 to 0.920g / cm 3 an ethylene / α-olefin copolymer fraction in an amount within a range of about 50% by weight or thickness of the first insert layer and an adhesive or bonding resin in an amount effective to improve the bonding of the first insert layer and the second insert layer to at least one other layer of the coextruded multilayer polymer film, wherein the combined density of the first insert layer and the second insert layer is about 0.910 g / cm 3 to 0.924g / cm 3 within the scope of (iii) a core barrier layer comprising from about 0.1% to about 10% by weight or total thickness of the coextruded multilayer polymeric film, or about 5% or less by weight or thickness of the barrier and non-barrier films combined, of ethylene vinyl alcohol (EVOH) copolymer, wherein the EVOH comprises at least 38% ethylene in the EVOH copolymer; and (iv) an outer sealing layer, the outer sealing layer comprising a density of 0.894 g / cm 3 to 0.920g / cm 3 The ethylene / α-olefin copolymer fraction is present in an amount of at least about 50% by weight or thickness of the total outer seal layer, wherein the outer seal layer has a total density of about 0.910 g / cm 3 to 0.924g / cm 3 within the scope of The bags passed a standard 40 inch drop test when filled with post-mix syrup.

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