Method to modify polymer recyclates and compositions made therefrom

Abstract

Provided is a method for modifying a polymer recyclate to improve one or more mechanical properties, wherein the polymer recyclate comprises a matrix phase of a low polarity polymer and a dispersed phase of domains of a high polarity condensation polymer. The polymer recyclate is mixed with a polar protic compound to contact at least a portion of the dispersed phase to reduce the molecular weight of the high polarity condensation polymer.

Description

METHOD TO MODIFY POLYMER RECYCLATES AND COMPOSITIONS MADE THEREFROMFIELD OF THE INVENTION

[0001] The present disclosure relates to methods for modifying polymer recy elates to improve one or more mechanical properties.BACKGROUND OF THE INVENTION

[0002] There has been much research and development to improve the processability of postconsumer recycle (PCR) resins, either alone or as a blend component with virgin polymers. Likewise, there has also been much effort by industry to develop end-use applications that incorporate PCR resins and have quality and / or performance similar or equal to corresponding end-use applications fabricated from virgin polymers. Existing and new environmental regulations provide continued motivation to develop suitable commercial uses of PCR resins while reducing the amount of waste plastics landfill. Successful development of these commercial pathways will create demand for products incorporating PCR resins.

[0003] Polyolefin / barrier multilayer packaging materials are used to combine the respective performance of different polymers in different layers. The multilayer structure package performs a combination of functions that is not possible with a single layer of one polymer. The multilayer packaging is created to protect sensitive food products sufficiently and obtain extended shelf life. A multilayer film typically comprises outer structural layers and one or more barrier layers disposed between the outer layers to provide a barrier to oxygen transmission. Structural layers provide mechanical properties such as tear resistance and puncture resistance and typically comprise polyolefins or low polarity ethylene or propylene copolymers. Barrier layers typically contain polymers containing polar groups such as, but not limited to, polyamide (nylon), polyester (PET), and / or ethylene vinyl alcohol (EVOH). When such multilayer films are recycled, incompatibility of the structural layers and the barrier layers results in a polymer recyclate comprising a matrix phase of the polyolefins or low polarity ethylene or propylene copolymers having a dispersed phase of domains of the polymers containing polar groups. The dispersed phase of domains of the polymers containing polar groups negatively affects the processability and mechanical properties of the polymer recyclate in comparison to analogous virgin polymers.

[0004] It would be desirable if such PCR resins could be treated in some manner to reduce the deleterious effects of these polar group-containing contaminants. Ideally, such treatment could be implemented with commonly used equipment and familiar techniques to provide treated PCR resins having utility in a broad range of end-use applications.SUMMARY OF THE INVENTION

[0005] The present disclosure relates to a method for modifying a polymer recyclate, wherein the polymer recyclate comprises a matrix phase of a low polarity polymer and a dispersed phase of domains of a high polarity condensation polymer. The polymer recyclate is mixed with a polar protic compound to contact at least a portion of the domains of the high polarity polymer under reaction conditions sufficient to produce a first modified polymer recyclate comprising a matrix phase of the low polarity' polymer and a dispersed phase of domains of a degraded high polarity condensation polymer, wherein the weight average molecular weight of the degraded high polarity' condensation polymer is less than the weight average molecular weight of the high polaritycondensation polymer.

[0006] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter, which form the subject matter of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying or designing other film structures and / or processes for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its structure and method of manufacture, together with further objects and advantages will be better understood from the following description.DETAILED DESCRIPTION OF THE INVENTION

[0007] Illustrative embodiments of the subject matter claimed below will now be disclosed. In the interest of clarity, some features of some actual implementations may not be described in this specification. It will be appreciated that in the development of any such actual embodiments, numerous implementation-specific decisions must be made to achieve the developer’s specific goals, such as compliance with system-related and business-related constraints, which will vary' from one implementation to another. Moreover, it will be appreciated that such a development effort, even if complex and time-consuming, would be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

[0008] The words and phrases used herein should be understood and interpreted to have a meaning consistent with the understanding of those words and phrases by those skilled in the relevant art. No special definition of a term or phrase, i.e.. a definition that is different from the ordinary and customary meaning as understood by those skilled in the art, is intended to be implied by consistent usage of the term or phrase herein. To the extent that a term or phrase is intended tohave a special meaning, i.e., a meaning other than the broadest meaning understood by skilled artisans, such a special or clarifying definition will be expressly set forth in the specification in a definitional manner that provides the special or clarifying definition for the term or phrase. It must also be noted that, as used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless otherwise specified.

[0009] For example, the following discussion contains a non-exhaustive list of definitions of several specific terms used in this disclosure (other terms may be defined or clarified in a definitional manner elsewhere herein). These definitions are intended to clarify the meanings of the terms used herein. It is believed that the terms are used in a manner consistent with their ordinary meaning, but the definitions are nonetheless specified here for clarity.Definitions

[0010] “Antioxidant agents,” as used herein, means compounds that inhibit oxidation, a chemical reaction that can produce free radicals and chain reactions. Antioxidants are differentiated based on their reaction mechanisms and include: (1) primary antioxidants, and (2) secondary antioxidants.

[0011] “Barrier layer,” as used herein, means a layer used in a multilayer film to impart gas impermeability in addition to other desired properties to a multilayer structure. Barrier layers herein comprise high polarity polymers.

[0012] “Compatibility,” as used herein, means the capability of the individual component substances in an immiscible polymer blend to exhibit interfacial adhesion, in which interfaces between phases or components are maintained by intermolecular forces, chain entanglements, or both, across the interfaces — i.e., holding together of two bodies by interfacial forces or mechanical interlocking on a scale of micrometers or less. Further discussion of miscibility can be found in D. W. Fox and R. B. Allen, "Compatibility’, Encyclopedia of Polymer Science and Engineering, 2nd Ed., J. I. Kroschwitz, ed., Wiley Interscience, New York, 1985, Vol. 3, p. 784. Work, W. J., Horie, K., Hess, M., & UK, R. S. (2004). Definitions of Terms Related to Polymer Blends, Composites and Multiphase Polymeric Materials, Pure and Applied Chemistry 76 / 11, the substance of which is fully incorporated herein by reference.

[0013] “Compounding conditions,” as used herein, means temperature, pressure, and shear force conditions implemented in an extruder to provide intimate mixing of two or more polymers and optionally additives to produce a substantially homogeneous polymer product. The compounding conditions will be such that the specific energy from the compounder from shear and / or added heat are sufficient to melt the polymer components and homogenize them.

[0014] “HDPE,” as used herein, means ethylene homopolymers and ethylene copolymers produced in a suspension, solution, slurry, or gas phase polymerization process and having a density in the range of 0.940 g / cm3to 0.970 g / cm3.

[0015] ‘‘High polarity polymer.” as used herein, means a polar polymer comprising a sufficiently high amount of polar monomer and / or comonomer to result in the polar polymer having a low oxygen vapor transmission rate (OVTR), as measured by ASTM D3985, such as less than or equal to 200 cc’pm / m2«day«atm. less than or equal to 150 cc»pm / m2»day»atm, less than or equal to 100 cc«pm / m2«dayatm, less than or equal to 50 cc«pm / m2«dayatm, or less than or equal to 2 cc»pm / m2»day*atm.

[0016] “LDPE,” as used herein, means ethylene homopolymers and / or ethylene copolymers produced in a high pressure free radical polymerization and having a density in the range of 0.90 g / cm3to 0.940 g / cm3.

[0017] “LLDPE,” as used herein, means ethylene copolymers produced in a suspension, solution, slurry, or gas phase polymerization process and having a density in the range of 0.90 g / cm3to 0.940 g / cm3.

[0018] “Low polarity polymer,” as used herein, means a polymer having a sufficiently low amount of polar monomer or comonomer to result in the low polarity polymer having a high oxygen vapor transmission rate (OVTR), as measured by ASTM D3985, such as greater than or equal to 800 cc»pm / m2»day»atm, greater than or equal to 900 cc»pm / m2»day,atm, or greater than or equal to 1,000 cc»pm / m2»day»atm. In some embodiments, the low polarity’ polymer comprises a polyolefin having no polarity', a copolymer of an olefin (such as ethylene or propylene) and an alpha mono-olefin comprising polar group, or a combination thereof. Low polarity polymers have a high degree of miscibility' and / or compatibility with other low polarity polymers and are further characterized as providing one or more of high moisture barrier, high tensile strength, high tear strength, and high puncture resistance as measure by dart drop.

[0019] “MDPE,” as used herein, means ethylene copolymers produced in a suspension, solution, slurry, or gas phase polymerization process and having a density in the range of 0.925 g / cm3to 0.940 g / cm3.

[0020] “Miscibility ,” as used herein, means the degree to which two polymers will mix to form a homogeneous polymer blends. Miscibility' is the capability of a mixture to form a single phase over certain ranges of temperature, pressure, and composition. Whether or not a single phase exists depends on the chemical structure, molar mass distribution, and molecular architecture of the components present. A single phase in a mixture may be confirmed by light scattering, x-ray scattering, and / or neutron scattering. For a two-component mixture, a necessary’ and sufficient condition for stable or metastable equilibrium of a homogeneous, single-phase is:d2miXG\> 0902] ' T,p wherein AmixG is the Gibbs energy of mixing per unit volume, and <D the composition, where <D is usually taken as the volume fraction of one of the component substances. The system is unstable if the above second derivative is negative. The borderline (spinodal) between (meta)stable and unstable states is defined by the above second derivative equaling zero. Further discussion of miscibility can be found in J.M.G. Cowie, ‘Miscibility’, Encyclopedia of Polymer Science and Engineering, 2nd Ed., J.I. Kroschwitz. ed., Wiley Interscience, New York, 1985, Supplement, p. 455-480, and Work, W. J., Horie, K., Hess. M., & UK. R. S. (2004), Definitions of Terms Related to Polymer Blends, Composites and Multiphase Polymeric Materials, Pure and Applied Chemistry76 / ll, the substance of which is fully incorporated herein by reference.

[0021] “Multilayer film,” as used herein, means a coextruded structure comprising at least a barrier layer, a structural layer, and a tie layer.

[0022] “Nonpolar comonomer,” as used herein, means a monomer unit containing only carbon and hydrogen.

[0023] “Nonpolar polymer,” as used herein, means a polymer or copolymer consisting of units derived from a nonpolar monomers.

[0024] “Olefin,” as used herein, and alternatively referred to as “alkene,” is a linear, branched, or cyclic compound of carbon and hydrogen having at least one double bond.

[0025] “Polar monomer,” as used herein, means monomers containing highly electronegative atoms, such as chlorine, fluorine, oxygen, nitrogen, or sulfur, that give rise to polymers that contain permanent electric dipoles.

[0026] “Polar polymer,” as used herein, means a polymer or copolymer comprising units derived from a polar monomer. The term "polar polymer," as used herein, refers to polymer formed from at least one monomer that comprises at least one heteroatom. Some examples of heteroatoms include O, N, P and S.

[0027] “Polymer recy elate,” as used herein, means post-consumer recycled (“PCR”) polymer and / or post-industrial recycled (“PIR”) polymer. Polymer recy elate is derived from an end product that has completed its life cycle as a consumer item and would otherwise be disposed of as waste (e.g., a polyethylene water bottle) or from plastic scrap that is generated as waste from an industrial process. Polymer recy elates herein are a mixture of a first low polarity polymer component and a high polarity polymer component comprising at least one polar monomer, such as produced by melting and mixing a barrier film having at least one layer of a first low polarity polymercomponent and at least on layer of a high polarity polymer component compnsing at least one polar monomer.

[0028] “Polyolefin,” as used herein, in some embodiments is a type of polymer with the general formula (CH2CHR)n where R is an alkyl group, including, but not limited to LDPE, LLDPE, MDPE, HDPE, and PP. Polyolefins are nonpolar polymers.

[0029] ‘Primary antioxidants,” as used herein, means compounds which function essentially as free radical terminators or scavengers. Primary antioxidants react rapidly with peroxy and alkoxy radicals. The majority of primary antioxidants for polymers are sterically hindered phenols.

[0030] “Processability.” as used herein, refers to how well a polymer composition can be formed into a cast of blown film of commercial quality or molded by injection or compression molding into a molded article of commercial quality at commercially acceptable rates using the equipment and conditions.

[0031] “Secondary antioxidants.” as used herein, means compounds which are preventive antioxidants that function by retarding chain initiation. Secondary antioxidants react with hydroperoxides to yield non-radical products and are, therefore, frequently called hydroperoxide decomposers.

[0032] “Structural layer,” as used herein, means a layer used in a multilayer film to impart desired mechanical properties and / or resistance to moisture to the multilayer structure.

[0033] In the present description, the terms “monomer” and “comonomer” are used interchangeably. The terms mean any compound with a polymerizable moiety' that is added to a reactor in order to produce a polymer. In those instances in which a polymer is described as comprising one or more monomers, e.g., a polymer comprising propylene and ethylene, the polymer, of course, comprises units derived from the monomers, e.g., — CEh — CH2 — , and not the monomer itself, e.g., CH2=CH2. For example, when a copolymer is described as having an “ethylene” content of 35 wt.% to 55 wt.%, it is understood that the mer unit in the copolymer is derived from ethylene in the polymerization reaction and the derived units are present at 35 wt.% to 55 wt.%. based upon the weight of the copolymer.

[0034] In the present description, “multilayer film” is of particular concern and discussed throughout this description. When referring to a multilayer structure, the description can use a slash to indicate that components to the left and right of the slash are in different layers and the relative position of components in layers can be so indicated by use of the slash to indicate layer boundaries.

[0035] The following abbreviations are used herein:'ABBREVIATION TERMEAA Copolymer of ethylene with acrylic acidEAO Copolymers of ethylene with at least one alpha-olefinABBREVIATION TERMEMAA Copolymer of ethylene with methacry lic acidEVA Copolymer of ethylene with vinyl acetateEVOH Saponified or hydrolyzed copolymer of ethylene and vinyl acetateHDPE High density polyethyleneIonomer Copolymers of ethylene and unsaturated carboxylic acid comonomers, such as but not limited to, EAA and EMAALDPE Low density polyethyleneLLDPE Linear low density polyethyleneMDPE Medium density polyethylenePA Polyamides, such as nylonPC PolycarbonatePCTFE PolychlorotrifluoroethylenePE Polyethylene (an ethylene homopolymer or copolymer of a major portion of ethylene with one or more alpha-olefins and / or one or more polar comonomers)PET Polyethylene terephthalatePETG Glycol-modified polyethylene terephthalatePP Polypropylene homopolymer or copolymerPS PolystyrenePVDC Poly vinylidene chloride (also includes copolymers of vinylidene chloride, such as with vinyl chloride or methyl acrylate (MA)). wt% weight percent

[0036] It is noted that in this disclosure and particularly in the claims and / or paragraphs, terms such as “comprises”, “comprised”, “comprising” and the like can have the meaning attributed to it in U.S. patent law; e.g.. they can mean “includes”, “included”, “including”, and the like; and that terms such as “consisting essentially of ' and “consists essentially of’ have the meaning ascribed to them in U.S. patent law, e.g., they allow for elements not explicitly recited, but exclude elements that are found in the prior art or that affect a basic or novel characteristic of the disclosure. Polymer Recyclate

[0037] Polymer recy elates herein have a matrix phase comprising a low polarity polymer with a dispersed phase of domains of a high polarity condensation polymer, wherein the low polarity polymer and the high polarity condensation polymer are incompatible. Such polymer recyclate can be derived from multilayer films, multilayer molded containers, or a combination thereof.Uow Polarity Polymer

[0038] In some embodiments, each of one or more low polarity’ polymers comprise one or more polyolefins. In some embodiments, a low polarity polymer is a blend of two or more polyolefins such as, but not limited to, a blend of low density polyethylene (LDPE), linear low’ density polyethylene (LUDPE), medium density polyethylene, high density polyethylene (HDPE), and / or polypropylene (PP).

[0039] In some embodiments, a low polarity polymer is a blend of two or more polymers such as, but not limited to, a blend of EVA, ionomers (such as, but not limited to, EAA and EMAA), EMA, ethylene-based copolymers compatible with polyethylene, or a combination thereof.

[0040] In some embodiments, a low polarity polymer is a blend of two or more of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene, high density polyethylene (HDPE), polypropylene (PP), EVA, ionomers (such as, but not limited to, EAA and EMAA), EMA, ethylene-based copolymers compatible with polyethylene, or a combination thereof.

[0041] Suitable polyethylenes for a low polarity polymer include ethylene homopolymers and copolymers of units derived from ethylene and units derived from one or more of C3-C20 alphaolefins or mixtures thereof. In some embodiments, the units derived from the one or more Cs-Cs alpha-olefin comonomers are present in amounts up to 15 wt. %, based upon the total weight of the copolymer of ethylene. The ethylene homopolymers and copolymers can be produced using either Ziegler Natta catalyst, chromium-based catalyst, or single-site catalyst, e.g., metallocene catalyst. The ethylene homopolymers and copolymers can be produced using a gas phase process, high pressure process, slurry process, or solution process. Ethylene homopolymers and ethylene- Cs-Cs alpha-olefin copolymers include very low density polyethylene (VLDPE), low density' polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE) and high density polyethylene (HDPE). VLDPE is defined as having a density of 0.860 to 0.910 g / cm3, as measured by ASTM D-1505 “Column Method.” LDPE and LLDPE are defined as having densities in the range of from 0.90 to 0.930 g / cm3. MDPE is defined as having a density' of 0.925 to 0.940 g / cm3. HDPE is defined as having a density of at least 0.945 g / cm3, preferably from 0.945 to 0.969 g / cm3. The ethylene homopolymers and copolymers preferably have melt indexes (Mis), as measured by ASTM D 1238, condition 190° C. / 2.16 kg, from 0.01 to 400 dg / min., preferably, from 0.1 to 200 dg / min., more preferably from 1 to 100 dg / min.

[0042] In some embodiments, LDPE is derived from ethylene homopolymers, copolymers of units derived from ethylene and units derived from one or more of C3-C12 alpha-olefins, copolymers of units derived from ethylene and units derived from one or more of alpha monoolefins comprising polar groups, or mixtures thereof.

[0043] In some embodiments, LDPE homopolymers can be produced in a high pressure, free- radical polymerization process, such as in one or more tubular reactors, one or more autoclave reactors, or a combination thereof. Operating conditions for the high-pressure process can include, but are not limited to, a pressure in the range of from 70 MPa to 700 MPa and a temperature in the range of from 150°C to 500°C. Such homopolymers have a high degree of long-chain branching and a density in the range of from 0.910 g / cm' to 0.940 g / cm3.

[0044] In some embodiments, LDPE copolymers of ethylene and C3-C12 alpha-olefins can be produced in a high pressure, free-radical polymerization process, such as in one or more tubular reactors, one or more autoclave reactors, or a combination thereof. Such C3-C12 alpha-olefins include, but are not limited to, substituted or unsubstituted C3 to C12 alpha olefins such as propylene, butene, pentene, hexene, heptene, octene. nonene, decene, undecene, dodecane, and isomers thereof. When present, comonomers can be present in amounts up to 15 wt%, 10 wt%, or 5 wt%. Operating conditions for the high-pressure process can include, but are not limited to, a pressure in the range of from 70 MPa to 700 MPa and a temperature in the range of from 150°C to 500°C. Such homopolymers have a high degree of long-chain branching and a density in the range of from 0.910 g / cm3to 0.940 g / cm3.

[0045] In some embodiments, LDPE copolymers of ethylene and one or more of alpha monoolefins comprising polar groups can be produced in a high pressure, free-radical polymerization process, such as in one or more tubular reactors, one or more autoclave reactors, or a combination thereof. Such alpha mono-olefins comprising polar groups include, but are not limited to, methacrylic acids, esters (e.g., acetate esters, such as vinyl acetate), nitriles, and amides, such as acrylic acid, methacrylic acid, cyclohexyl methacrylate, methyl acrylate, acrylonitrile, acrylamide, or mixtures thereof. When present, comonomers can be present in amounts up to 15 wt%, 10 wt%, or 5 wt%. Operating conditions for the high-pressure process can include, but are not limited to, a pressure in the range of from 70 MPa to 700 MPa and a temperature in the range of from 150°C to 500°C. Such homopolymers have a high degree of long-chain branching and a density in the range of from 0.910 g / cm3to 0.940 g / cm3.

[0046] LDPE as described above, can be characterized by having: i) a density in the range of from 0.90 g / cm3to 0.940 g / cm3or from 0.915 g / cm3to 0.935 g / cm3; ii) a melt index (2.16 kg, 190°C) less than or equal to 5.0 g / 10 min., less than or equal to 1.0 g / 10 min., less than or equal to 0.5 g / 10 min., less than or equal to 0.2 g / 10 min., or less than or equal to 0.1 g / 10 min.; iii) a molecular weight distribution (Mw / Mn) greater than 4.0, greater than 8.0, or greater than 15, and / or less than 35, less than 30. or less than 25; iv) a weight average molecular weight (Mw) greater than or equal to 100,000 daltons, greater than or equal to 150,000 daltons, greater than or equal to 200,000 daltons, or greater than or equal to 250,000 daltons, and / or less than or equal to 600,000 daltons, less than or equal to 500,000 daltons, less than or equal to 400,000 daltons, or less than or equal to 300,000 daltons; and v) a melt elasticity ("ER") greater than or equal to 1.0, greater than or equal to 1.4, or greater than or equal to 2.0.

[0047] Suitable polypropylenes for a low polarity polymer include propylene homopolymers and copolymers, including plastomers, having of units derived from propylene and units derived one or more of ethylene and C4-C20 alpha-olefins or mixtures thereof. Preferably, the units derivedfrom one or more of ethylene and C4-C10 alpha-olefin comonomers are present in amounts up to 35 wt. %, based upon the total weight of the copolymer of propylene. The propylene homopolymers and copolymers can be produced using either Ziegler Natta or single-site catalysts, e.g., metallocene catalysts. The propylene homopolymers and copolymers can be produced using a gas phase process, slurry process, or solution process. In some embodiments, when the propylene polymer is a copolymer, it preferably contains 2 to 6 wt. %, based upon the total weight of the copolymer, of ethylene derived units as a comonomer.

[0048] In some embodiments, a first low polarity polymer component comprises a copolymer of ethylene and one or more polar comonomer, a copolymer of propylene and one or more polar comonomers, or a combination thereof, wherein the low first polarity polymer component has an oxygen vapor transmission rate (OVTR), as measured by ASTM D3895, of greater than or equal to 800 cc«pm / m2«dayatm. greater than or equal to 900 cc*pm / m2*dayatm, or greater than or equal to 1,000 cc’pm / m2«dayatm.

[0049] A low polarity polymer can also be formed from a blend of two or more polyethylenes, two or more polypropylenes, or one or more polyethylenes and one or more polypropylenes. In some embodiments, a low polarity polymer can also be formed from a blend of two or more polyolefins, two or more olefin-based polymers (other than but compatible with polyolefins), or one or more polyolefins and one or more olefin-based polymers (other than but compatible with polyolefins).High Polarity Condensation Polymer

[0050] In some embodiments, a high polarity condensation polymer herein comprises a polymer having an oxygen vapor transmission rate (OVTR). as measured by ASTM D3895, of less or equal to 200 cc,pm / m2«day,atm, less than or equal to 150 cc»pm / m2»day»atm, less than or equal to 100 cc’pm / m2«day»atm, less than or equal to 50 cc’pm / m2«day»atm, or less than or equal to 2 cc«pm / m2«dayatm. A barrier layer can include polyester, a polyamide, a polycarbonate, a polyvinyl alcohol, a polyurethane, an ethylene vinyl alcohol, or a combination thereof.

[0051] Polyesters are a category of polymers that contain the ester functional group in their main chain. While polyethylene terephthalate (PET) is the most common type of polyester used in packaging, several other polyesters also possess properties that can be useful in barrier layers in multilayer films or molded containers. In some embodiments, a polyester comprises polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polycyclohexylenedimethylene terephthalate (PCT), polytrimethylene terephthalate (PTT), polyglycolic acid (PGA), polylactic acid (PLA), polyethylene furanoate (PEF), or a combination thereof.

[0052] Polyamides (PAs), often known as nylons, are a group of polymers that provide a good barrier against gases like oxygen and carbon dioxide, making them valuable in packaging, especially for food products that need protection from oxygen to ensure freshness and quality. They also have excellent mechanical properties, chemical resistance, and are typically used in combination with other materials in multilayer fdms to exploit these properties. In some embodiments, a polyester comprises PA 6 (nylon 6), PA 66 (nylon 6,6), PA 11, PA 12, PA 6 / 66 copolymer, PA 6 / 12 copolymer, PA 6 / 66 / 6T copolymer, PA 6I / 6T, MXD6 (Polyamide MXD6), bio-based polyamides, or a combination thereof.

[0053] Polycarbonates (PC) are a group of thermoplastic polymers known for their transparency, toughness, and excellent impact resistance. They also have good temperature resistance, making them suitable for applications requiring these properties. However, standard polycarbonate materials generally do not have exceptional barrier properties against gases like oxygen or carbon dioxide, which are often crucial for packaging applications. Still, they are used in multilayer structures for their other properties, often in combination with materials that do provide good gas barrier properties. The term "polycarbonates" refers to a category of polymers that are characterized by the carbonate group in their chemical structures. The most common ty pe of polycarbonate is based on bisphenol A (BPA), but there are several other polycarbonates, including those developed to address concerns about the potential health effects of BPA. In some embodiments, a polycarbonate comprises bisphenol A polycarbonate (BPA-PC), bisphenol S polycarbonate (BPS-PC), bisphenol F polycarbonate (BPF-PC), bisphenol C polycarbonate (BPC- PC), bisphenol Z polycarbonate (BPZ-PC), bisphenol-free polycarbonates, polycarbonate copolymers, aliphatic polycarbonates, or a combination thereof.

[0054] Polyvinyl alcohols (PVAs) are synthetic resins prepared by the polymerization of vinyl acetate, followed by hydrolysis of the polyvinyl acetate. They are used in a variety of applications due to their emulsifying and adhesive properties, as well as resistance to oil, grease, and solvents. They are also notable for their barrier properties, particularly in preventing gas and aroma permeabilities, making them useful as a barrier layer in multilayer films. In some embodiments, a polycarbonate comprises fully hydrolyzed PVA, partially hydrolyzed PVA, high molecular weight PVA, low7molecular weight PVA, modified PVA, copolymerized PVA, or a combination thereof.

[0055] Polyurethanes (PUs) are versatile polymers that are known more for their elasticity, toughness, and chemical resistance than for their barrier properties. However, they can still play a crucial role in certain barrier applications, particularly when resistance to solvents, oils, or greases is required, or when their elasticity and durability7provide added value. In some embodiments, a polycarbonate comprises thermoplastic polyurethane (TPU), polyether polyurethane, polyesterpolyurethane, polycaprolactone polyurethane, aliphatic polyurethane, aromatic polyurethane, waterborne polyurethane, polyurethane foams, bio-based polyurethane, or a combination thereof.

[0056] Ethylene vinyl alcohol (EVOH) is a class of polymers known for its exceptional gas barrier properties, high resistance to oils and organic solvents, and flexibility . It is a copolymer of ethylene and vinyl alcohol. EVOH is typically coextruded with other materials in multilayer packaging for food, medical, pharmaceutical, cosmetic, and automotive fuel applications due to its ability to retain gases and flavors and prevent external contamination. In some embodiments, an ethylene vinyl alcohol comprises low ethylene content EVOH (typically around 24% to 32%), medium ethylene content EVOH (typically around 38% to 44%), high ethylene content EVOH (typically around 48% to 72%), or a combination thereof. Higher ethylene content provides more flexibility' and better moisture resistance, while higher vinyl alcohol content provides more rigidity and better gas barrier properties.Polar Protic Compound

[0057] Polar protic compounds are a subset of molecules that possess both polarity and the ability to form hydrogen bonds, typically via a hydrogen atom attached to an electronegative element such as oxygen, nitrogen, or fluorine. These molecules’ polarity’ arises from the uneven distribution of electron density, resulting in a molecule with a distinct dipole moment, characterized by partial positive (5+) and negative (5-) charges. The ‘protic’ aspect refers to these compounds’ proclivity to donate protons (H+) in reactions, facilitated by the hydrogen atoms’ loosely held status, bonded to electronegative atoms.

[0058] In some embodiments, a polar protic compound comprises water, an alcohol, a carboxylic acid, an amine, an amide, or a combination thereof.

[0059] In some embodiments, water is a desirable polar protic compound due to its polarity, high dielectric constant, and capability for hydrogen bonding.

[0060] In some embodiments, an alcohol is a desirable polar protic compound, and can include simple alcohols, polyols, or a combination thereof. In some embodiments, simple alcohols comprise a Ci-Ce alcohol, such as, but not limited to, methanol, ethanol, propanol, butanol, isopropyl alcohol, or a combination thereof. In some embodiments, polyols comprise a Ci-Ce polyol, such as, but not limited to, glycerol, propylene glycol, ethylene glycol, sorbitol polyethylene glycol, propylene glycol (PEG), ery thritol, or a combination thereof.

[0061] In some embodiments, a carboxylic acid is a desirable polar protic compound, and can include Ci-Ce carboxylic acids, such as, but not limited to, acetic acid, formic acid, citric acid, or a combination thereof.

[0062] In some embodiments, an amine is a desirable polar protic compound, and can include amines, such as, but not limited to, methylamine, ethylamine, aniline, or a combination thereof.

[0063] In some embodiments, an amine is a desirable polar protic compound, and can include amides, such as, but not limited to, acetamide, benzamide, urea, or a combination thereof.

[0064] In some embodiments, a polar protic compound comprises water, a Ci-Ce alcohol, a C1-C6 carboxylic acid, a Ci-Ce polyol, or a combination thereof.Polymer Recvclate Treatment Process

[0065] The polymer recyclate is prepared for mixing with a polar protic compound. In order to achieve the desired reduction of molecular weight of the high polarity condensation polymer in the dispersed phase domains, the polar protic compound must contact at least a portion of the domains of the high polarity condensation polymer. In some embodiments, the polymer recyclate is modified in a solution process to produce a first modified polymer recyclate. In some embodiments, the polymer recyclate is modified in a compounding process to produce a first modified polymer recyclate. As the molecular weight of the high polarity condensation polymer is reduced, the dispersion of the high polarity polymer within the low polarity polymer matrix can be improved. One advantage of this modification is the minimization of domain size of the dispersed high polarity polymer (or low gel level). As a result, mechanical properties of polymer recyclate can be improved, including, but not limited to, one or more of mechanical elongation, strength, toughness, environmental stress crack resistance (ESCR), structural integrity', puncture resistance, heat resistance, heat sealability', and / or abrasion resistance.Solution Method

[0066] In some embodiments, that polymer recyclate is prepared or provided as a particulate matter, such as, but not limited to, pellets, granules, or powder. In some embodiments, a quantity of polymer recyclate particles are immersed in a solution comprising the polar protic compound. In some embodiments, the size of the particles is selected to provide a desired ratio of surface area per unit volume of the particles of polymer recyclate. A higher ratio of surface area per unit volume of the particles of polymer recyclate will enable the polar protic compound to contact a greater portion of the domains of the the high polarity condensation polymer to enable reducing the molecular weight of a greater proportion of the high polarity condensation polymer in the polymer recyclate.

[0067] In some embodiments, after a threshold time period a first modified polymer recyclate is recovered and separated from the solution. In some embodiments, the threshold time period is greater than or equal to 1 minute, greater than or equal to 5 minutes, or greater than or equal to 10 minutes. In some embodiments, the threshold time period is less than or equal to 3 hours, less than or equal to 2 hours, or less than or equal to 1 hour. In some embodiments, during the threshold time period, the solution comprising the polar protic compound and the polymer recyclate can be unagitated, intermittently agitated, or continuously agitated. In some embodiments, thetemperature of the solution comprising the polar protic compound and the polymer recyclate during the threshold time period is in the range of from -10°C to just below the boiling point of the solution, from 0°C to 10°C below the boiling point of the solution, from 10°C to 20°C below the boiling point of the solution, or from 20°C to 30°C below the boiling point of the solution.

[0068] In some embodiments, the polymer recyclate melt comprises the polar protic compound in an amount in the range of from 500 ppmw to 5 wt%, based on the total weight of the polymer recyclate melt and the polar protic compound.

[0069] The high polarity condensation polymer in the polymer recy clate has a first weight average molecular weight (Mwi). and the degraded high polarity condensation polymer in the first modified polymer recyclate has a second weight average molecular weight (MW2>, wherein Mw? is less than Mwi. In some embodiments, Mw Mwi is less than or equal to 0.9, less than or equal to 0.8, less than or equal to 0.7, less than or equal to 0.6, or less than or equal to 0.5.

[0070] In some embodiments, the method further comprises blending the first modified polymer recyclate with a functionalized polymer as described below to form a second modified polymer recyclate. In some embodiments, the functionalized polymer is present in the blend of the first modified polymer recyclate and the functionalized polymer in an amount in the range of from 0.5 wt.% to 30 wt.%, or 1 wt.% to 20 wt.%, or 2 wt.% to 15 wt.%, or 5 wt. % to 15 wt. %, or 6 wt.% to 11 wt. %. based on the total weight of the polymer recyclate melt, the polar protic compound, and the functionalized polymer. The functional groups of the functional polymer are compatible with the domains of degraded high polarity condensation polymer and act to more uniformly distribute the domains of degraded high polarity condensation polymer and / or to compatibilize the domains of degraded high polarity condensation polymer with the low polarity polymer matrix.Compounding Method

[0071] In some embodiments, the polymer recyclate and a polar protic compound are fed to an extruder, a mixer, or any apparatus capable of compounding conditions sufficient to melt and mix the polymer recyclate. In some embodiments, compounding conditions are implemented in the compounding zone of an extruder or mixer and are tailored for mixtures of specific low polarity polymers and polar protic compounds. Temperature, pressure, and shear force conditions are implemented in the extruder or mixer sufficient to provide intimate mixing of the w polarity polymers, graft agents, optionally one or more initiators, to produce polymer chains comprising free radicals and / or graft agents comprising free radicals. The compounding conditions will be such that the specific energy from the compounder from shear and / or added heat are sufficient to melt the polymer components and homogenize them with the other components in the mixture in the extruder or mixer. In some embodiments, compounding conditions comprise a temperature inthe compounding zone of less than or equal to 300°C, less than or equal to 250°C or less than or equal to 200°C. In some embodiments, where the polymer recy elate comprises a polyethylene, temperatures in the compounding zone can be in the range of from 125°C to 195°C, from 130°C to 180°C, or from 135°C to 165°C. In some embodiments, where the polymer recy elate comprises a polypropylene, temperatures in the compounding zone can be in the range of from 175°C to 245°C, from 180°C to 230°C, or from 185°C to 215°C. During compounding, the polar protic compound reacts with the domains of the high polarity condensation polymer to reduce the molecular weight of the high polarity condensation polymer. A first modified polymer recyclate is withdrawn from the extruder or mixer, wherein the first modified polymer recyclate comprises a matrix phase of the low polarity polymer and a dispersed phase of domains of the degraded high polarity condensation polymer.

[0072] The high polarity' condensation polymer in the polymer recyclate has a first weight average molecular weight (Mwi). and the degraded high polarity condensation polymer in the first modified polymer recyclate has a second weight average molecular weight (MW2>, wherein Mw? is less than Mwi. In some embodiments, Mw2 / Mwiis less than or equal to 0.9, less than or equal to 0.8, less than or equal to 0.7, less than or equal to 0.6, or less than or equal to 0.5.

[0073] The first modified polymer recyclate withdrawn from the extruder can be pelletized for later mixing a functionalized polymer as described below or can be blended in the melted state with such functionalized polymer to form a second modified polymer recyclate. In some embodiments, the functionalized polymer is present in the blend of the first modified polymer recyclate and the functionalized polymer in an amount in the range of from 0.5 wt.% to 30 wt.%, or 1 wt.% to 20 wt.%, or 2 wt.% to 15 wt.%, or 5 wt. % to 15 wt. %, or 6 wt.% to 11 wt. %, based on the total weight of the polymer recyclate melt, the polar protic compound, and the functionalized polymer. The functional groups of the functional polymer are compatible with the domains of degraded high polarity' condensation polymer and act to more uniformly distribute the domains of degraded high polarity condensation polymer and / or to compatibilize the domains of degraded high polarity condensation polymer with the low polarity polymer matrix.Functionalized Polymer

[0074] In some embodiments, a functionalized polymer as disclosed herein comprises a modified polymer produced by reacting a polymer with functional groups or monomers, such as acid and / or acid derivative moi eties, wherein the polymer has the one or more functional groups or monomers grafted along the polymer chain. In some embodiments, the modified polymer is a functionalized polyolefin, functionalized low polarity polymer (including polyolefin), or a combination thereof. In some embodiments, the low' polarity' polymer and / or the polyolefin is a polymer recyclate.

[0075] In some embodiments, the second low polarity polymer is a polyolefin such as a polyethylene homopolymer or copolymer. In some embodiments, the polyolefin is a polypropylene homopolymer or copolymer.

[0076] In some embodiments, the polymer is a low polarity polymer (other than polyolefin). In some embodiments, the low polarity’ polymer is a copolymer of ethylene and one or more polar comonomers. In some embodiments, the low polarity polymer is a copolymer of propylene and one or more polar comonomers.

[0077] In some embodiments, the functionalized polymer is formed by addition of one or more pendant functional groups to a polymer backbone comprising a low polarity polymer (including polyolefin). The polyolefin can be an ethylene homopolymer or copolymer of ethylene and one or more alpha olefins. The low polarity' polymer (other than polyolefin) can be a copolymer of ethylene and one or more alpha mono-olefins comprising polar groups or a copolymer of propylene and one or more alpha mono-olefins comprising polar groups.

[0078] In some embodiments, functionalized polymer as disclosed herein comprises a modified low polarity polymer produced by reacting a low polarity' polymer with functional groups or monomers, such a carboxylic acid, a carboxylic acid derivative, an acid derivative, an anhydride, an anhydride derivative, and combinations thereof, wherein the low polarity' polymer has the one or more functional groups or monomers grafted along the polymer chain.

[0079] Functionalized polymers are generally formed by grafting a functional monomer onto the backbone (i.e., main chain) of a low polarity polymer. The composition of the low polarity polymer can be a polyolefin comprising a single ethylene-based polymer, a single propylene-based polymer, a blend of two or more ethylene-based polymers, a blend of two or more propylene-based polymers, or a blend of at least one ethylene-based polymer and at least one propylene-based polymer. Suitable ethylene-based polymers and propylene-based polymers are described below. The one or more polymers selected from ethylene-based polymers, propylene-based polymers, and combinations thereof selected for the composition of the olefin-base polymer can be the same as or different from those chosen for the composition of the polyolefin of the one or more structural layers of the multilayer barrier film.

[0080] The functional groups included in the functionalized polymer are selected for having miscibility’ and / or compatibility with the barrier layer composition. The low polarity’ polymer portion of the functionalized polymer is selected for having miscibility and / or compatibility with the structural layer composition.

[0081] The functional monomer can be grafted onto the polarity polymer via processes known to one skilled in the art. For example, the graft may be formed via reactive extrusion processes.Reactive extrusion processes generally include contacting the low polarity polymer with the functional monomer within an extruder or in a solution process to form the functionalized polymer.

[0082] The reactive extrusion processes may include any extrusion process known in the art. For example, raw7materials (e.g., low polarity polymer and functional monomer) may be fed into a tw in screw extruder in a concentration sufficient to form the functionalized low polarity polymer having a target graft content. The reaction to form the functionalized low polarity polymer may occur in the twin screws extruder under constant mixing and kneading, for example. Thus, the functionalized low polarity polymer generally includes a linear backbone of the polarity polymer with randomly distributed branches of the functional monomer, resulting in side chains that are structurally distinct from the main chain / backbone.

[0083] In one or more embodiments, the low polarity polymer contacts the functional monomer in the presence of an initiator. Initiators can be selected from those known to one skilled in the art, such as, but not limited to, organic peroxides. However, as discussed previously herein, grafting can take place under high temperature and high shear in absence of an initiator.

[0084] In some embodiments, functionalized polymers of the invention are conveniently prepared by grafting the low polarity polymer in the substantial absence of solvent. This can be accomplished in a shear-imparting reactor, such as an extruder / reactor. Twin screw7extruder / reactors such as those manufactured by Coperion (formerly Wemer-Pfleiderer) under the designations ZSK.-53, ZSK-83 and ZSK-92 are commonly used. A free radical generating catalyst, such as an organic peroxide catalyst, can be employed but is not necessary. The grafting reaction is carried out at a temperature selected to minimize or avoid rapid vaporization and consequent losses of the graft monomer and any catalyst that may be employed. The graft monomer concentration in the reactor is typically about 1 to about 5 wt. % based on the total reaction mixture w eight. A temperature profile w here the temperature of the low polarity polymer melt increases gradually through the length of the extruder / reactor up to a maximum in the grafting reaction zone and then decreases toward the reactor exit is preferred. The maximum temperature within the reactor should be such that significant vaporization losses and / or premature decomposition of any peroxide catalyst are avoided. For example, if di-t-butyl peroxide and 2,5-dimethyl-2,5-di-(t- butylperoxy) hexane are used, temperatures within the reactor are maintained at or below7about 220°C. Examples of useful peroxide catalysts include: l,l-bis(t-butylperoxy)cyclohexane; n- butyl-4.4-bis(t-butylperoxy-valerate); l,l-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane: 2,2- bis(t-butyl-peroxy)butane; dicumylperoxide; t-butylcumylperoxide; alpha, alpha'-bis(t- butylperoxy-preoxy-isopropyl)benzene; di-t-butylperoxide; 2,5-dimethyl-2,5-di(t-butylperoxy) hexane; and the like. The grafting monomer and any catalyst used are preferably added in neat form to the extruder / reactor.

[0085] In some embodiments, compounding conditions are implemented in the compounding zone of an extruder or mixer and are tailored for mixtures of specific low polarity polymers, graft agents, optionally one or more initiators, and optionally additives. Temperature, pressure, and shear force conditions are implemented in the extruder or mixer sufficient to provide intimate mixing of the w polarity polymers, graft agents, optionally one or more initiators, to produce polymer chains comprising free radicals and / or graft agents comprising free radicals. The compounding conditions will be such that the specific energy from the compounder from shear and / or added heat are sufficient to melt the polymer components and homogenize them with the other components in the mixture in the extruder or mixer. In some embodiments, compounding conditions comprise a temperature in the compounding zone of less than or equal to 300°C, less than or equal to 250°C or less than or equal to 200°C. In some embodiments, where the polymer recyclate comprises a polyethylene, temperatures in the compounding zone can be in the range of from 125°C to 195°C. from 130°C to 180°C, or from 135°C to 165°C. In some embodiments, where the polymer recyclate comprises a polypropylene, temperatures in the compounding zone can be in the range of from 175°C to 245°C, from 180°C to 230°C, or from 185°C to 215°C. The polymer recyclate can be pelletized for later mixing a functionalized polymer as described below or can be blended in the melted state with such functionalized polymer.

[0086] In a preferred embodiment, the functionalized polymer, i.e., functionalized low polarity polymer, is obtained by grafting an ethylenically unsaturated carboxylic acid or derivative, particularly MAH, onto the polymer backbone. The grafting may be accomplished using know n procedures in solution, in a fluidized bed reactor, by melt grafting or by irradiation grafting. As used herein, the term grafting denotes covalent bonding of the grafting monomer to the polymer chain.

[0087] The functionalized polymer may include the functional monomer in a range of from 0.10 wt% to 2.9 wt%, from 0.45 wt% to 2.8 wt%, from 0.70 wt% to 2.7 wt%, from 1.05 wt% to 2.6 wt%, from 1.50 wt% to 2.5 wt%, wherein weight percentages are based on the total weight of the functionalized polymer.

[0088] In some embodiments, the functionalized polymer has a melt index (b) in the range of from 0.5 dg / min. to 600 dg / min., 1.0 dg / min. to 500 dg / min., from 3.0 dg / min. to 400 dg / min., from 5.0 dg / min. to 300 dg / min., from 7.0 dg / min. to 200 dg / min., or from 9.0 dg / min. to 100 dg / min.

[0089] In some embodiments, the functionalized polymer has a density in the range of from 0.850 g / cm’ to 0.960 g / cm3, from 0.855 g / cnT to 0.950 g / cn , from 0.860 g / cm3to 0.940 g / cm3, from 0.865 g / cm3to 0.930 g / cm3, or from 0.870 g / cm3to 0.920 g / cm3.

[0090] In some embodiments, the functionalized polymer has a melt elasticity (ER) in the range of from 0.30 to 3.00, from 0.31 to 2.35, from 0.32 to 1.70, from 0.33 to 1.05, or from 0.34 to 0.40.

[0091] In some embodiments, the functionalized polymer has a melting temperature (Tm) in the range of from 50°C to 170 °C, from 51°C to 145°C, from 52°C to 125°C, from 53°C to 105°C, from 54°C to 85°C, or from 55°C to 65°C.Applications

[0092] In some embodiments, the first modified polymer recy elate and / or the second modified polymer recyclate can by used in place of or in a blend with an analogous virgin polymer to form a film, a layer of a multilayer film, a molded container, or a layer of a multilayer molded container. Certain Embodiments

[0093] Disclosed is a method for producing a modified polymer recyclate product. The method comprises providing a polymer recyclate comprising a matrix phase of a low polarity polymer and a dispersed phase of domains of a high polarity condensation polymer. The polymer recyclate is mixed with a polar protic compound. The polar protic compound is contacted with at least a portion of the domains of the high polarity polymer under reaction conditions sufficient to produce a first modified polymer recyclate comprising a matrix phase of the low polarity polymer and a dispersed phase of domains of a degraded high polarity condensation polymer. The high polarity condensation polymer in the polymer recyclate has a first weight average molecular weight (Mwi), and the degraded high polarity' condensation polymer in the first modified has a second weight average molecular weight (MW2), and MW2 is less than Mwi.

[0094] In some embodiments of the method for producing a modified polymer recyclate product, in addition to the above limitations, the method is further characterized by one or more of the following: a) M„2 / Mwi is less than or equal to 0.9, less than or equal to 0.8, less than or equal to 0.7, less than or equal to 0.6, or less than or equal to 0.5; b) the high polarity polymer has an oxygen vapor transmission rate (OVTR) less than or equal to 200 cc*pm / m2*day»atm, and the low polarity polymer has an OVTR greater than or equal to 800 cc’pm / m2«day»atm; c) the high polarity condensation polymer comprises a polyester, a polyamide, a polycarbonate, a polyvinyl alcohol, a polyurethane, ethylene vinyl alcohol, or a combination thereof; d) the polar protic compound comprises water, a Ci-Ce alcohol, a Ci-Ce carboxylic acid, a Ci-Ce polyol, or a combination thereof; and e) the low polarity polymer comprises:i) a copolymer of units derived from ethylene and units derived from one or more of C3-C20 alpha-olefins or mixtures thereof ii) a copolymer of units derived from ethylene and units derived from one or more of alpha mono-olefins comprising polar groups; iii) a copolymer of units derived from propylene and units derived one or more of ethylene and C4-C20 alpha-olefins or mixtures thereof; iv) a copolymer of units derived from propylene and units derived one or more of ethylene and units derived from one or more of alpha mono-olefins comprising polar groups; or v) a combination thereof.

[0095] In some embodiments, the method for producing a modified polymer recy elate product is a solution process comprising one or more of the above limitations of the method for producing a modified polymer recyclate product, wherein the reaction conditions of the solution process comprise immersion of particles of the polymer recyclate in a solution of the polar protic compound for a time period in the range of from 1 minute to 3 hours. In some embodiments of the solution process, the reaction conditions further comprise a reaction temperature in the range of from -10°C to just below the boiling point of the solution.

[0096] In some embodiments, the method for producing a modified polymer recyclate product is a compounding process comprising one or more of the above limitations of the method for producing a modified polymer recyclate product, wherein the reaction conditions of the compounding process comprise heat and / or mechanical shear sufficient to form a polymer recyclate melt, wherein the polymer recyclate melt further comprises the polar protic compound in an amount in the range of from 500 ppmw to 5 wt%, based on the total weight of the polymer recyclate melt and the polar protic compound.

[0097] In some embodiments, the method for producing a modified polymer recyclate product, the solution process, or the compounding process, further comprises blending the first modified polymer recyclate with a functionalized polymer to form a second modified polymer recyclate, wherein the functionalized polymer comprises a base polymer grafted with one or more functional groups, and the base polymer is compatible with the low polarity polymer of the polymer recyclate. In further embodiments, the blending step is further characterized by one or more of the following: a) the one or more functional groups are selected from the group consisting of a carboxylic acid, a carboxylic acid derivative, an acid derivative, an anhydride, an anhydride derivative, and combinations thereof; b) the functionalized polymer comprises one or more functional groups in an amount in the range of from 0.10 wt% to 2.9 wt%, from 0.45 wt% to 2.8 wt%, from 0.70 wt% to2.7 wt%, from 1.05 wt% to 2.6 wt%, from 1.50 wt% to 2.5 wt%, wherein weight percentages are based on the total weight of the functionalized polymer; and c) the functionalized polymer is present in an amount up to 30 wt%, in the range of from 0.5 wt.% to 30 wt.%, or 1 wt.% to 20 wt.%, or 2 wt.% to 15 wt.%, or 5 wt. % to 15 wt. %, or 6 wt.% to 11 wt. %, based on the total weight of the polymer recy elate melt, the polar protic compound, and the functionalized polymer.EXAMPLES

[0098] The following examples are included to demonstrate preferred embodiments of the invention. It should be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.Test Methods

[0099] Densities are determined in accordance with ASTM D-792 and ASTM D-1505 / ISO-1183.

[0100] Shear rheological measurements are performed in accord with ASTM 4440-95a, which characterize dynamic viscoelastic properties (storage modulus, G', loss modulus, G” and complex viscosity, r / as a function of oscillation frequency, co). A rotational rheometer (TA Instruments) is used for the rheological measurements. A 25 mm parallel-plate fixture was utilized. Samples were compression molded in disks (~ 29 mm diameter and ~ 1.3 mm thickness) using a hot press at 190 °C. An oscillatory frequency sweep experiment (from 398.1 rad / s to 0.0251 rad / s) was applied at 190°C. The applied strain amplitude is - 10% and the operating gap is set at 1 mm. Nitrogen flow was applied in the sample chamber to minimize thermal oxidation during the measurement.

[0101] Dart drop (g): Measurements were made following ASTM DI 709-04 (2016), using a dart drop height of 26 in (F50).

[0102] Elongation at break (%): Elongation at break was measured according to ASTM D-638.

[0103] Film Elmendorf Tear (g / mil) was made according to ASTMD 1922.

[0104] Gloss (45°) is measured as specified by ASTM D2457.

[0105] Haze (%): Film haze measurements were made following ASTM D1003.

[0106] Melt elasticity (“ER”) is determined as discussed in R. Shroff and H. Mavridis, “New Measures of Polydispersity from Rheological Data on Polymer Melts,’’ J. Applied PolymerScience 57 ( 1995) 1605. See also U.S. Pat. Nos. 7.238.754, , 171.993 and 5.534,472 (col. 19. lines 20-30), the teachings of which are incorporated herein by reference. Thus, storage modulus (G’) and loss modulus (G") are measured. The nine lowest frequency points are used (five points per frequency decade) and a linear equation is fitted by least-squares regression to log G’ versus log G". ER is then calculated from:ER = (1.781 x 10") x G' at a value of G"=5,000 dyn / cm2. The same procedure and equation for the ER calculation was used for both linear and long-chain-branched polyolefins.

[0107] Melt index (“I2”) was determined by ASTM D-1238-E (190°C / 2. 16 kg).

[0108] Molecular weight distribution (“MWD”) as well as the molecular weight averages (number-average molecular weight, Mn weight-average molecular weight, Mw, and z-average molecular weight, Mz) are determined using a high temperature Polymer Char gel permeation chromatography (“GPC”), also referred to as size exclusion chromatography (“SEC”), equipped with a filter-based infrared detector, IR5. a four-capillary differential bridge viscometer, and a Wyatt 18-angle light scattering detector. Mn, Mw, Mz,MWD, and short chain branching (SCB) profiles are reported using the IR detector, whereas long chain branch parameter, g’, is determined using the combination of viscometer and IR detector at 145°C. Three Agilent PLgel Olexis GPC columns are used at 145°C for the polymer fractionation based on the hydrodynamic size in 1,2,4- trichlorobenzene (TCB) with 300 ppm antioxidant butylated hydroxytoluene (BHT) as the mobile phase. 16 mg polymer is weighted in a 10 mL vial and sealed for the GPC measurement. The dissolution process is obtained automatically (in 8 ml TCB) at 160°C for a period of 1 hour with continuous shaking in an Agilent autosampler. 20 pL Heptane was also injected in the vial during the dissolution process as the flow marker. After the dissolution process, 200 pL solution was injected in the GPC column. The GPC columns are calibrated based on twelve monodispersed polystyrene (PS) standards (provided by PSS) ranging from 578 g / mole to 3,510,000 g / mole. The comonomer compositions (or SCB profiles) are reported based on different calibration profiles obtained using a series of relatively narrow polyethylene (polyethylene w ith 1 -hexene and 1- octene comonomer were provided by Polymer Char, and polyethylene with 1 -butene were synthesized internally) with known values of CH3 / IOOO total carbon, determined by an established solution NMR technique. GPC one software was used to analyze the data. The long chain branch parameter, g’, is determined by the equation: g’ = [T|] / [ll]lin where, |q | is the average intrinsic viscosity of the polymer that is derived by summation of the slices over the GPC profiles as follows:where ci is the concentration of a particular slice obtained from IR detector, and [p] j is the intrinsic viscosity of the slice measured from the viscometer detector, [q] iinis obtained from the IR detector using Mark-Houwink equation ([q]lin= 2 KM31*5113) for a linear high density polyethylene, where Mi is the viscosity-average molecular weight for a reference linear polyethylene, K and a are Mark-Houwink constants for a linear polymer, which are K=0.000374, a=0.7265 for a linear polyethylene and K=0.00041, a=0.6570 for a linear polypropylene.

[0109] Oxygen gas transmission rate (OVTR) can be measured by ASTM D3985.

[0110] Narrow Angle Scatter: Film NAS measurements were made following ASTM D1746 (2015) Standard Test Method for Transparency of Plastic Sheeting. Multi-layer film specimens can be cut into 10 cm x 10 cm squares and adhered to the test unit in front of the light source by air suction. Films can be oriented in the same direction and tested in the same fashion to minimize testing variables. A minimum of six specimens can be run for each sample.

[0111] Polar polymer domain size (in the examples herein. EV OH) was measured by Scanning Electron Microscopy (SEM) which is described, for example, in an article to F. Mirabella, et al. entitled "Morphological Explanation of the Extraordinary Fracture Toughness of Linear Low Density Polyethylenes", J. Polymer Science: Part B: Polymer Physics, Vol. 26, No. 9, August 1988, pp. 1995-2005. Specifically, the following procedure was employed in the present invention to determine the volume percent polar polymer in the barrier film recyclate resin comprising a mixture of nonpolar polymer and polar polymer. A compression-molded sample of the film recyclate resin was microtomed at a specimen temperature of about -80°C in an LKB Ultratome V with Cryokit. The bulk specimen thus prepared was etched in n-heptane at 60°C for 20 minutes in a sonic bath, mounted onto a scanning electron microscope specimen stub, and sputter coated with approximately 200 A of gold. The specimen was then analyzed in an ISI-40 SEM. This procedure removes any rubbery, amorphous or low-crystallinity, in the resin from the specimen surface and leaves definable cavities where the material was originally located. Photomicrographs were statistically analyzed with a Ziess Videoplan Image Analyzer.

[0112] Tensile stress at break (MPa): Tensile stress at break was measured according to ASTM D-638. This test is dependent on film sample thickness. For the measurements provided here, a thickness of about 46 pm to 55 pm was used.Materials to be used in experimentsStarting materials

[0113] Starting materials for the examples below are shown in TABLE 1 below. Film examples can have a structure of first layer / tie layer / second layer. Nonpolar polymer NP1 couldbe used as a first layer. Polar polymer (PCP1 ) could be used as a second layer. Functional polymer FPV1 is based on a virgin low polarity polymer. Functional polymer FPR1 could be prepared based on a recyclate low polarity' polymer.TABLE 1Polymer Recy elate

[0114] A proxy for polymer recyclate could be prepared melt blending HDPE and nylon as shown in Table 2. Each of the polymer recyclate proxies is tested to determine the molecular weight of the high polarity condensation polymer PCP1 in the dispersed phase of the polymer blend. GPC or SEC can be used to measure the molecular weight of high polarity polymers in polymer blends or multilayer structures. A solvent that selectively dissolves the high polarity polymer but not the low polarity polymers, such as formic acids or acetyl chloride, is used to recover the high polarity polymer from the polymer blend. After selective extraction of high polarity' polymer from polymer blends or multilayer structures, GPC or SEC is used to determine its molecular weight.TABLE 2

[0115] Polymer recyclate proxies are then compounded at 250°C with 1,000 ppmw of water to produce a first modified polymer recyclate as shown in Table 3. Each of the first modified polymer recyclates is tested to determine the molecular weight of the degraded high polarity condensation polymer d-PCPl in the dispersed phase of the polymer blend.TABLE 3

[0116] Without wishing to be bound by any particular theory, it is believed that d-MWl is less than MW1, d-MW2 is less than MW2, and d-MW3 is less than MW3. It is further believed that each of m-PCRl, m-PCR2, and m-PCRl, when compared to PCR1, PCR2, and PCR1, respectively, would demonstrate reduced gel levels resulting in improved mechanical properties, including, but not limited to, one or more of mechanical elongation, strength, toughness, environmental stress crack resistance (ESCR), structural integrity7, puncture resistance, heat resistance, heat sealability, and / or abrasion resistance.

[0117] For the sake of brevity, only certain ranges are explicitly disclosed herein. However, in addition to recited ranges, any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as, ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited, in the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. Additionally, within a range includes every point or individual value between its end points even though not explicitly recited. Thus, every point or individual value may serve as its own low er or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited.

[0118] All documents and references cited herein, including testing procedures, publications, patents, journal articles, etc., are herein fully incorporated by reference for all jurisdictions in which such incorporation is permitted and to the extent such disclosure is consistent with the description of the present invention.

[0119] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein w ithout departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the processes, machines, film structures, composition of layers, means, methods, and / or steps described in the specification. As one of the ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, film structures, composition of layers, means, methods, and / or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as thecorresponding embodiments described herein, may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, film structures, composition of layers, means, methods, and / or steps.

Claims

CLAIMSWhat is claimed is:

1. A method for producing a modified polymer recy elate product, the method comprising: providing a polymer recyclate comprising a matrix phase of a low polarity polymer and a dispersed phase of domains of a high polarity condensation polymer; mixing the polymer recyclate with a polar protic compound; contacting the polar protic compound with at least a portion of the domains of the high polarity polymer under reaction conditions sufficient to produce a first modified polymer recyclate comprising a matrix phase of the low polarity polymer and a dispersed phase of domains of a degraded high polarity' condensation polymer: wherein: the high polarity condensation polymer has a first weight average molecular weight (Mwi); the degraded high polarity' condensation polymer has a second weight average molecular weight (MW2); and less than Mwi.

2. The method of claim 1, wherein Mw2 / Mwiis less than or equal to 0.9, less than or equal to 0.8, less than or equal to 0.7, less than or equal to 0.6, or less than or equal to 0.5.

3. The method of claim 1 or 2, wherein: the high polarity polymer has an oxygen vapor transmission rate (OVTR) less than or equal to 200 cc’pm / m2’dayatm; and the low polarity polymer has an OVTR greater than or equal to 800 cc*pm / nr*day*atm.

4. The method of any one of claims 1 through 3, wherein the high polarity' condensation polymer comprises a polyester, a polyamide, a polycarbonate, a polyvinyl alcohol, a polyurethane, ethylene vinyl alcohol, or a combination thereof.

5. The method of any one of claims 1 through 4, wherein the polar protic compound comprises water, a C1-C6 alcohol, a Ci-Ce carboxylic acid, a Ci-Ce polyol, or a combination thereof.

6. The method of any one of claims 1 through 5, wherein the low polarity polymer comprises:a copolymer of units derived from ethylene and units derived from one or more of C3-C20 alpha-olefins or mixtures thereof; a copolymer of units derived from ethylene and units derived from one or more of alpha mono-olefins comprising polar groups; a copolymer of units derived from propylene and units derived one or more of ethylene and C4-C20 alpha-olefins or mixtures thereof; a copolymer of units derived from propylene and units derived one or more of ethylene and units derived from one or more of alpha mono-olefins comprising polar groups; or a combination thereof.

7. The method of any one of claims 1 through 6, wherein the reaction conditions comprise immersion of particles of the polymer recyclate in a solution of the polar protic compound for a time period in the range of from 1 minute to 3 hours.

8. The method of claim 7, wherein the reaction conditions comprise a reaction temperature in the range of from -10°C to just below the boiling point of the solution.

9. The method of any one of claims 1 through 6, wherein the reaction conditions comprise heat and / or mechanical shear sufficient to form a polymer recyclate melt, wherein the polymer recyclate melt further comprises the polar protic compound in an amount in the range of from 500 ppmw to 5 wt%, based on the total weight of the polymer recyclate melt and the polar protic compound.

10. The method of any one of claims 1 through 9, further comprising blending the first modified polymer recyclate with a functionalized polymer to form a second modified polymer recyclate. wherein: the functionalized polymer comprises a base polymer grafted with one or more functional groups; and the base polymer is compatible with the low polarity polymer.

11. The method of claim 10, wherein the one or more functional groups are selected from the group consisting of a carboxylic acid, a carboxylic acid derivative, an acid derivative, an anhydride, an anhydride derivative, and combinations thereof.

12. The method of claim 10 or 11, wherein the functionalized polymer comprises one or more functional groups in an amount in the range of from 0.10 wt% to 2.9 wt%.

13. The method of any one of claims 10 through 12, wherein the functionalized polymer is present in an amount up to 30 wt%, based on the total weight of the polymer recyclate melt, the polar protic compound, and the functionalized polymer.

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