Recycled polyolefin films and laminates

Abstract

A recycled polymer composition including (a) a post-consumer recycled (PCR) or post-industrial recycled (PIR) polyolefin film and (b) at least one surfactant. The polyolefin film includes (i) at least one polyolefin polymer and (ii) one or more adhering or coating auxiliaries. The adhering or coating auxiliaries typically are coatings and adhesives which include one or more of inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, and polyurethanes. The surfactant is non-ionic, zwitterionic, cationic, anionic, or a metal salt. Further, the recycled polymer composition includes 0.1 to 1.5 wt.% of the surfactant by weight of the recycled polymer composition.

Description

85729-WO-PCT / DOW 85729 WO RECYCLED POLYOLEFIN FILMS AND LAMINATES CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 604,467 filed November 30, 2023, the contents of which are incorporated in their entirety herein. TECHNICAL FIELD

[0002] Embodiments described herein generally relate to mechanically recyclable polymer compositions and specifically relate to mechanically recyclable polymer compositions generated from recycled polyolefin film in combination with at least one surfactant as well as articles generated from the recycled polymer composition. BACKGROUND

[0003] The use of plastic products, for example, packaging materials for the packaging industry, has significantly increased globally. Consequently, the increase in demand for plastic products has created a significant increase in plastic waste because after a plastic product has been used by the consumer the plastic product is discarded by the consumer. The plastic waste detrimentally impacts the environment and landscape throughout the world. To alleviate or reduce the plastic waste problem, manufacturers have attempted to produce a plastic product that can be recycled and reprocessed into other subsequent plastic products after the original plastic product has been used for its original purpose. However, many plastics include adhesives and / or coating which are typically not chemically compatible with polyolefins forming the remainder of the plastic article. This results in challenges during attempted recycling as the incompatible adhesives and / or coatings appear in micron- to millimeter-sized gels in the resins and films generated from the recycled plastics. The gels can severely undermine the appearance and mechanical performance of the newly formed articles and films and in some situations, the presence of gels makes extrusion impossible. SUMMARY85729-WO-PCT / DOW 85729 WO

[0004] Accordingly, there is an ongoing need for the development of a plastic product which includes adhesives and / or coatings which is fully recyclable. To meet these needs, surfactants may be included in the compounding step during formation of recycled polymer compositions to improve the mechanical properties of post-consumer recycled films containing adhering or coating auxiliaries such as adhesives and / or coatings. The current commercial recycling of waste plastics typically involves mixing the reclaimed plastics with virgin plastics in a variety of reclaimed:virgin ratios, spanning from 1:99 to 99:1 by weight. In accordance with various aspects of the present disclosure, surfactants can be used in a masterbatch of virgin polyethylene resins that can be blended with reclaimed flexible packages to produce post- consumer recycled packaging films.

[0005] According to at least one embodiment of the present disclosure, a recycled polymer composition is provided. The recycled polymer composition includes (a) a post-consumer recycled (PCR) or post-industrial recycled (PIR) polyolefin film and (b) at least one surfactant. The polyolefin film includes (i) at least one polyolefin polymer, and (ii) one or more adhering or coating auxiliaries. The surfactant is non-ionic, zwitterionic, cationic, anionic, or a metal salt and is provided in the recycled polymer composition at 0.1 to 1.5 wt.% of the recycled polymer composition.

[0006] According to at least one further embodiment of the present disclosure, a recycled polymer composition is provided. The recycled polymer composition includes (a) a post-consumer recycled (PCR) or post-industrial recycled (PIR) polyolefin film and (b) at least one surfactant. The polyolefin film includes (a) at least one first polymer film layer, the first polymer film layer comprising a first polyolefin polymer; (b) at least one second polymer film layer, the first polymer film layer comprising a second polyolefin polymer; and (c) one or more adhering or coating auxiliaries, wherein the adhering or coating auxiliaries comprise an adhesive comprising one or more inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, or polyurethanes. Further, the adhesive is disposed on the surface of at least one of the layers of the first film layer and the second film layer for binding the first film layer and the second film layer together. Additionally, the surfactant is non-ionic, zwitterionic, cationic, anionic, or a metal salt and is provided in the recycled polymer composition at 0.1 to 1.5 wt.% of the recycled polymer composition.85729-WO-PCT / DOW 85729 WO

[0007] According to at least one further embodiment of the present disclosure, a recycled polymer composition is provided. The recycled polymer composition includes (a) a post-consumer recycled (PCR) or post-industrial recycled (PIR) polyolefin film and (b) at least one surfactant. The polyolefin film includes (i) at least one polyolefin polymer, and (ii) one or more adhering or coating auxiliaries which form a coating layer on a surface of the polyolefin film. Further, the coating layer comprises one or more inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, or polyurethanes. Additionally, the surfactant is non-ionic, zwitterionic, cationic, anionic, or a metal salt and is provided in the recycled polymer composition at 0.1 to 1.5 wt.% of the recycled polymer composition.

[0008] These and other embodiments are described in more detail in the following Detailed Description. DETAILED DESCRIPTION

[0009] Specific embodiments of the present application will now be described. These embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the subject matter to those skilled in the art.

[0010] The term “recyclable” or “recyclability” herein, with reference to a first article including one or more adhering or coating auxiliaries and at least one surfactant, means mechanically recyclable or mechanical recyclability; and means the first article including the one or more adhering or coating auxiliaries and the surfactant is mechanically re-processable to generate a second article having a desirable performance range, wherein the second article has at least a less than 33 % decreased change in mechanical performance relative to the performance of a control article that is without any of the one or more adhering or coating auxiliaries adhering or coating auxiliaries at is reprocessed the same way as the second article. An example, and not to be limited thereby, of testing methods and guidelines for determining recyclability of a plastic article can be found in publication “Critical Guidance Protocol for PE Film and Flexible Packaging”, Document Number FPE-CG-01 (Revision date – August 2, 2022) of The Association of Plastic Recyclers (APR).85729-WO-PCT / DOW 85729 WO

[0011] The term “composition,” as used herein, refers to a mixture of materials which comprises the composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0012] “Polymer” means a polymeric compound prepared by polymerizing monomers, whether of the same or a different type. The generic term polymer thus embraces the term homopolymer (employed to refer to polymers prepared from only one type of monomer, with the understanding that trace amounts of impurities can be incorporated into the polymer structure), and the term interpolymer as defined hereinafter. Trace amounts of impurities (for example, catalyst residues) may be incorporated into and / or within the polymer. A polymer may be a single polymer, a polymer blend or a polymer mixture, including mixtures of polymers that are formed in situ during polymerization.

[0013] The term “interpolymer,” as used herein, refers to polymers prepared by the polymerization of at least two different types of monomers. The generic term interpolymer thus includes copolymers (employed to refer to polymers prepared from two different types of monomers), and polymers prepared from more than two different types of monomers.

[0014] The terms “olefin-based polymer” or “polyolefin”, as used herein, refer to a polymer that comprises, in polymerized form, a majority amount of olefin monomer, for example ethylene or propylene (based on the weight of the polymer), and optionally may comprise one or more comonomers.

[0015] The term, “ethylene / a-olefin interpolymer,” as used herein, refers to an interpolymer that comprises, in polymerized form, a majority amount (e.g., greater than [>] 50 mole percent [mol %]) of units derived from ethylene monomer, and the remaining units derived from one or more a-olefins. Typical a-olefins used in forming ethylene / a-olefin interpolymers are C3-C10 alkenes.

[0016] The term, “ethylene / a-olefin copolymer,” as used herein, refers to a copolymer that comprises, in polymerized form, a majority amount (> 50 mol %) of ethylene monomer, and an a-olefin, as the only two monomer types.

[0017] The term “a-olefin”, as used herein, refers to an alkene having a double bond at the primary or alpha (a) position.85729-WO-PCT / DOW 85729 WO

[0018] “Polyethylene (PE)” or “ethylene-based polymer” shall mean polymers comprising a majority amount (> 50 mol %) of units which have been derived from ethylene monomer. This includes polyethylene homopolymers, ethylene / a-olefin interpolymers, and ethylene / a-olefin copolymers. Common forms of polyethylene known in the art include low density polyethylene (LDPE); linear low density polyethylene (LLDPE); ultra low density polyethylene (ULDPE); very low density polyethylene (VLDPE); medium density polyethylene (MDPE); high density polyethylene (HDPE); enhanced polyethylene; polyethylene elastomers; and polyethylene plastomers. These PE materials are generally known in the art; however, the following descriptions may be helpful in understanding the differences between some of these different PE resins. The term “LDPE” may also be referred to as “high pressure ethylene polymer” or “highly branched polyethylene” and is defined to mean that the polymer is partly or entirely homopolymerized or copolymerized in autoclave or tubular reactors at pressures above 14,500 pounds per square inch (psi) (100 megapascal [MPa]) with the use of free-radical initiators, such as peroxides (see for example U.S. Patent Nos. 8,916,667; 8,871,887; 8,822,601; 9,228,036; and 9,765,160). LDPE resins typically have a density in the range of 0.916 grams per cubic centimeter (g / cm3) to 0.935 g / cm3.

[0019] The term “LLDPE”, includes both resins made using the traditional Ziegler-Natta catalyst systems and chromium-based catalyst systems as well as single-site catalysts, including, but not limited to, bis-metallocene catalysts (sometimes referred to as “m-LLDPE”), constrained geometry catalysts (CGC), and molecular catalysts. Resins include linear, substantially linear, or heterogeneous polyethylene copolymers or homopolymers. LLDPEs contain less long chain branching than LDPEs and includes the substantially linear ethylene polymers which are further defined in U.S. Patent Nos. 5,272,236; 5,278,272; 5,582,923; and 5,733,155; the homogeneously branched linear ethylene polymer compositions such as those described in U.S. Patent No. 3,645,992; the heterogeneously branched ethylene polymers such as those prepared according to the process disclosed in U.S. Patent No.4,076,698; and / or blends thereof (such as those disclosed in U.S. Patent No. 3,914,342 or U.S. Patent No. 5,854,045). The LLDPEs can be made via gas- phase, solution-phase or slurry polymerization; or any combination thereof, using any type of reactor or reactor configuration known in the art.

[0020] The term “MDPE” refers to polyethylenes having densities from 0.926 g / cm3to 0.940 g / cm3. “MDPE” is typically made using chromium or Ziegler-Natta catalysts or using85729-WO-PCT / DOW 85729 WO singlesite catalysts including, but not limited to, bis-metallocene catalysts, constrained geometry catalysts, and molecular catalysts; and typically have a molecular weight distribution (“MWD”) > 2.5.

[0021] The term “HDPE” refers to polyethylenes having densities greater than 0.940 g / cm3and up to 0.970 g / cm3, which are generally prepared with Ziegler-Natta catalysts, chrome catalysts or single-site catalysts including, but not limited to, bis-metallocene catalysts and constrained geometry catalysts.

[0022] The term “ULDPE” refers to polyethylenes having densities of 0.880 g / cm3to 0.912 g / cm3, which are generally prepared with Ziegler-Natta catalysts, chrome catalysts, or single-site catalysts including, but not limited to, bis-metallocene catalysts and constrained geometry catalysts. "Polyethylene plastomers / elastomers" are substantially linear, or linear, ethylene / a-olefin copolymers containing homogeneous short-chain branching distributions comprising units derived from ethylene and units derived from at least one C3-C10 a-olefin comonomer, or at least one C4-C8 a-olefin comonomer, or at least one C6-C8α-olefin comonomer. Polyethylene plastomers / elastomers have a density from 0.870 g / cm3, or 0.880 g / cm3, or 0.890 g / cm3to 0.900 g / cm3, or 0.902 g / cm3, or 0.904 g / cm3, or 0.909 g / cm3, or 0.910 g / cm3, or 0.917 g / cm3. Non-limiting examples of polyethylene plastomers / elastomers include AFFINITY™ plastomers and elastomers (available from The Dow Chemical Company), EXACT Plastomers (available from ExxonMobil Chemical), TAFMER™ (available from Mitsui Chemicals), NEXLENE™ (available from SK Chemicals Co.), and LUCENE™ (available from LG Chemical Ltd.); and mixtures thereof.

[0023] “Blend”, “polymer blend” and like terms mean a composition of two or more polymers. Such a blend may or may not be miscible. Such a blend may or may not be phase separated. Such a blend may or may not contain one or more domain configurations, as determined from transmission electron spectroscopy, light scattering, x-ray scattering, and any other method known in the art. Blends are not laminates, but one or more layers of a laminate may contain a blend. Such blends can be prepared as dry blends, formed in situ (e.g., in a reactor), melt blends, or using other techniques known to those of skill in the art.

[0024] The terms “pre-consumer recycled polymer” and “post-industrial recycled polymer” (“PIR”) refer to polymers, including blends of polymers, recovered from pre-consumer85729-WO-PCT / DOW 85729 WO material, as defined by ISO-14021. The generic term pre-consumer recycled polymer thus includes blends of polymers recovered from materials diverted from the waste stream during a manufacturing process. The generic term pre-consumer recycled polymer excludes the reutilization of materials, such as rework, regrind, or scrap, generated in a process and capable of being reclaimed within the same process that generated it.

[0025] The term “post-consumer recycled resin” or “post-consumer recycled polymer” (“PCR”), as used herein, refers to a polymeric material, including blends of polymers, recovered from materials previously used in a consumer or industry application, as defined by ISO-14021. The generic term post-consumer recycled resin thus includes blends of polymers recovered from materials generated by households or by commercial, industrial, and institutional facilities in their role as end-users of the material, which can no longer be used for its intended purpose. The generic term post-consumer recycled resin also includes blends of polymers recovered from returns of materials from the distribution chain. PCR resin is often collected from recycling programs and recycling plants. The PCR resin may include one or more of a polyethylene, a polypropylene, a polyester, a poly(vinyl chloride), a polystyrene, an acrylonitrile butadiene styrene, a polyamide, an ethylene vinyl alcohol, an ethylene vinyl acetate, or a poly-vinyl chloride. The PCR resin may include one or more contaminants. The contaminants may be the result of the polymeric material’s use prior to being repurposed for reuse. For example, contaminants may include paper, ink, food residue, or other recycled materials in addition to the polymer, which may result from the recycling process

[0026] PCR resin is distinct from virgin polymeric material. A virgin polymeric material does not include materials previously used in a consumer or industry application. Virgin polymeric material has not gone through consumer or industrial use, like a typical PCR resin. The physical, chemical, and flow properties of PCR resins differ when compared to virgin polymeric resin, which in turn can present challenges to incorporating PCR resin into formulations for commercial use.

[0027] The terms “comprising,” “including,” “having,” and their derivatives, are not intended to exclude the presence of any additional component, step or procedure, whether or not the same is specifically disclosed. In order to avoid any doubt, all compositions claimed through use of the term “comprising” may include any additional additive, adjuvant, or compound,85729-WO-PCT / DOW 85729 WO whether polymeric or otherwise, unless stated to the contrary. In contrast, the term, “consisting essentially of’ excludes from the scope of any succeeding recitation any other component, step or procedure, excepting those that are not essential to operability. The term “consisting of’ excludes any component, step or procedure not specifically delineated or listed.

[0028] An objective of the present invention is to process post-industrial recycled or post- consumer recycled material which comprises at least one polyolefin polymer and one or more adhering or coating auxiliaries into a recycled polymer composition for manufacture of recycled articles.

[0029] The recycled polymer composition includes a combination of: (a) a post-consumer recycled (PCR) or post-industrial recycled (PIR) polyolefin film and (b) at least one surfactant. The polyolefin film includes (i) at least one polyolefin polymer, (ii) one or more adhering or coating auxiliaries. It has been found that inclusion of the surfactant in the recycled polymer composition imparts a recyclability property to the post-consumer recycled (PCR) or post- industrial recycled (PIR) polyolefin film; and thus, the post-consumer recycled (PCR) or post- industrial recycled (PIR) polyolefin film is rendered recyclable and can be used to produce recycled articles for various other applications. Specifically, the adhering or coating auxiliaries forming at least a portion of the polyolefin film are typically not chemically compatible with polyolefins and as a result, they appear in micron- to millimeter-sized gels in recycled resins and films generated from PCR or PIR polyolefin film comprising adhering or coating auxiliaries. The recycled polymer composition and processes of the present disclosure address such undesirable gels with the inclusion of the surfactant to effectively integrate the adhering or coating auxiliaries with the remaining polyolefins to generate recycled articles for various other applications.

[0030] In some non-limiting embodiments, the PCR or PIR polyolefin film of the present disclosure may be provided as a film such as a monolayer or multilayer film, a multilayer laminate, a packaging product, and the like. Further, PCR or PIR polyolefin film may be provided in a pelletized form. In some non-limiting embodiments, the recycled articles generated from the recycled polymer composition of the present disclosure may also include, for example, one or more of the following articles: a pellet, a film such as a monolayer or multilayer film, a multilayer laminate, a packaging product, and the like.85729-WO-PCT / DOW 85729 WO

[0031] The polyolefin polymer, component (i), provided with the PCR or PIR polyolefin film can include one or more polyolefins. Generally, the polymeric portion of the polyolefin film is comprised of at least 80 % of a polyolefin polymer in one embodiment, at least 85 % of a polyolefin polymer in another embodiment, and at least 90 % of a polyolefin polymer in still another embodiment. In one embodiment, the polyolefin polymer is at least one PE polymer. For example, the PE polymer, can include one or more of HDPE, LDPE, LLDPE, and mixtures thereof. The polyolefin film may be a monolayer or a multilayer film. In further embodiments, the polyolefin is polypropylene (PP), oriented PP (OPP), biaxially oriented PP (BOPP), and mixtures thereof.

[0032] The one or more adhering or coating auxiliaries, component (ii), provided with the PCR or PIR polyolefin film can be a coating and / or adhesives utilized in the formation of the PCR or PIR polyolefin film. It is noted cured laminating adhesives and packaging coatings are referred to as “adhering or coating auxiliaries”, and grammatical variations thereof, in this disclosure. Specifically, production of laminates, packages, and other polymer film based structures which are typically utilized as post-consumer or post-industrial recycled polymers include adhesives to bind layers together and / or coatings to provide abrasion resistance, UV light protection, printable layers, or other desirable attribute. These adhesive and coatings are collectively referenced as adhering or coating auxiliaries.

[0033] The surfactant, component (b), useful for making the recycled polymer composition in accordance with the present disclosure provides for integration of the adhering or coating auxiliaries during recycling of the PCR and / or PIR polyolefin film. The surfactant provided as a component of the recycled polymer composition comprises at least one surfactant which is non-ionic, zwitterionic, cationic, anionic, or a metal salt.

[0034] Having generally described the components of the recycled polymer composition, embodiments of the recycled polymer composition and the various components will be provided in further detail.

[0035] As aforementioned, the recycled polymer composition can be formed from a wide variety of polyolefins such as films, laminates, or packages and the like. Therefore, as an illustration only and not to be limited thereby, the PCR and / or PIR polyolefin film is described herein with reference to a preferred embodiment which is a monolayer or multilayer laminate85729-WO-PCT / DOW 85729 WO structure, and more particularly, a multilayer laminate structure commonly encountered in consumer packages. It is, however, understood by one skilled in the art that many other articles can serve as the PCR and / or PIR polyolefin film other than a laminate; and that the present invention is not limited thereto.

[0036] In one broad embodiment, the present disclosure includes recycling a multilayer laminate structure as the PCR or PIR polyolefin film. The laminate structure is typical for a laminated packaging material in consumer good allowing for recycling of such packaging. The multilayer laminate includes the combination of at least two polyolefin layer substrates adhered together by a layer of adhesive. For example, the multilayer laminate structure comprises: (i) at least a first polymer film layer comprising a first polyolefin polymer, such as a polyethylene (PE) film; (ii) at least a second polymer film layer comprising a second polyolefin polymer which can also be the same as the first polyolefin polymer or a different material; and (iii) a layer of adhesive comprising one or more inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, or polyurethanes described above for bonding the first and second polyolefin film layers together; and wherein the layer of adhesive is disposed on the surface of at least one of the layers of the first film layer and the second film layer for binding the first film layer and the second film layer together. One or more other optional film layer substrates can be added to the above laminate structure with the adhesive added in-between multiple layers to produce a multi-layer laminate structure comprising more than two layers, if desired. Further, the laminate may further comprise a coating layer comprising one or more inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co- polyethylenes, polyesters, acrylics, or polyurethanes.

[0037] The first polymer film layer and the second polymer film layer, components (i) and (ii), used for making the multilayer laminate of the present disclosure can include one or more polyolefins. For example, each of the first polymer film layer and the second polymer film layer, can include one or more polyolefin layers such as HDPE, LDPE, LLDPE, MDO PE, BOPE, and mixtures thereof.

[0038] In one or more embodiments, the first polymer film layer can include, for example, a polyethylene film web which is bonded to the second polymer film layer through an adhesive.85729-WO-PCT / DOW 85729 WO Similarly, in one or more embodiments, the second polymer film layer can include, for example, a polyethylene film web which is bonded to the first polymer film layer through an adhesive.

[0039] In one or more embodiments, the first polymer film layer can include a multilayer film which is bonded to the second polymer film layer through an adhesive. Similarly, in one or more embodiments, the second polymer film layer can include a multilayer film which is bonded to the first polymer film layer through an adhesive.

[0040] In various embodiments, the adhesives compositions utilized in the PIR and / or PCR polyolefin film may be poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, or polyurethanes, and mixtures thereof. Example adhesives include acrylic based materials formed from an acrylic emulsion of acrylic monomers such as ethyl acrylate, methyl methacrylate, butyl acrylate, acrylic acid, methacrylic acid, incorporated with polypropylene glycol, and cured with isocyanate. In one or more preferred embodiments, the adhesive may be a polyurethane based adhesive composition. Generally, the adhesive of the present disclosure may encompass those useful in products such as fresh and frozen produce packaging, general snack packaging, and other consumer packaging.

[0041] The laminate structure of the present disclosure can include other optional layered substrates, component (iv), in addition to the above component layers (i)-(iiii). For example, substrates such as EVOH, PVDC, OPA, and mixtures thereof can be laminated (bonded) to the above first and second layers, if desired.

[0042] In general, the PCR and PIR polyolefin films can be sourced from polyolefin films utilized in a wide range of applications including, for example, packaging materials and products. For example, the PCR and PIR polyolefin films can be from bulk packaging of food grains / pulses, packaging of seeds, packaging of lentils and cereals, packaging of fertilizer, packaging of oilseed, packaging of sugar, packaging of salt, packaging of pharmaceuticals, packaging of other food stuff, and personal care items such as bath salts, detergent pods and the like. The PCR and PIR polyolefin films may also be from a wrapper for baby wipes, feminine hygiene products, cereal bars, protein bars, cheese, and confectionary products. The recycled polymer composition of the present disclosure can be used to produce further packing materials as well as non-packaging materials reducing waste.85729-WO-PCT / DOW 85729 WO

[0043] The surfactant may be at least one of the following: non-ionic surfactants, zwitterionic surfactants, cationic surfactants, anionic surfactants, or a metal salt. or a combination thereof. Each surfactant type may achieve improved recyclability and improved mechanical performance for polyolefin films with varying adhering or coating auxiliaries. The surfactants typically have a molar mass of less than 5,000 grams per mole (g / mol).

[0044] In one or more embodiments the surfactant may be provided in the recycled polymer composition at a concentration of 0.1 to 1.5 percent by weight (wt%). In various further embodiments, the compatibilizer may be provided in the recycled polymer composition at a concentration of 0.1 to 1.2 wt%, 0.3 to 1.5 wt%, 0.3 to 1.0 wt%, 0.1 to 0.8 wt%, 0.3 to 0.8 wt%, or 0.4 to 0.6 wt%. All percentages are based on the weight of the blend of the post-consumer recycled (PCR) or post-industrial recycled (PIR) polyolefin film and any virgin resins.

[0045] In one or more embodiments, the surfactant is a non-ionic surfactant. A non-ionic surfactant combines uncharged hydrophilic and hydrophobic groups. Commercially available non-ionic surfactants include Span 85, Span 80 (Sigma-Aldrich), Tergitol™ NP-9 (Dow Chemical Company), and Triton™ X-100 (Dow Chemical Company). Span 85 Span 85 is made from oleic acid and the sugar alcohol sorbitol with a molar mass of 957.51 g / mol. Span 85 is alternatively known as Sorbitan Trioleate (STO). Similarly, Span 80 is made from oleic acid and the sugar alcohol sorbitol with a molar mass of 428.60 g / mol. Span 80 alternatively known as Sorbitan Monooleate (SMO). Tergitol™ NP-9 is a nonionic surfactant based on nonylphenol ethoxylate and has a molar mass of 616.833 g / mol. Finally, Triton X-100 is a nonionic surfactant that has a hydrophilic polyethylene oxide chain and an aromatic hydrocarbon lipophilic or hydrophobic group and has a molar mass of 647 g / mol. In one or more preferred embodiments, the surfactant is a sorbitan ester such as Span 80 or Span 85.

[0046] In one or more embodiments, the surfactant is a zwitterionic surfactant. A zwitterionic surfactant is at least one surfactant that has both positive and negative charges within the same molecule, typically at the hydrophilic end of the surfactant. Zwitterionic surfactants can be anionic (negatively charged), cationic (positively charged), or non-ionic (no charge), depending on the acidity of the solution and the existence of other components. These charges can either be permanent or dependent on the pH value. An example of a commercially available zwitterionic85729-WO-PCT / DOW 85729 WO surfactant is Everstab FS042 (Everspring Chemical). Everstab FS042 is an oxidized bis(hydrogenated tallow alkyl) amine with a molar mass of 537.99 g / mol.

[0047] In one or more embodiments, the surfactant is a cationic surfactant. A cationic surfactant a type of surfactant that has a positively charged hydrophilic head along with a hydrophobic tail. Commercially available cationic surfactants include Hexadecyltrimethylammonium bromide and Trihexyltetradecylphosphonium chloride which are widely available form a variety of manufacturers including Sigma Aldrich. Hexadecyltrimethylammonium bromide has a molar mass of 364.45 g / mol. Hexadecyltrimethylammonium bromide is alternatively known as CTAB. Trihexyltetradecylphosphonium chloride has a molar mass of 519.31 g / mol.

[0048] In one or more embodiments, the surfactant is a metal salt. Metal salts are chemical compounds that have a neutral charge and are made up of a metal ion and either an acid or a nonmetal. An example metal salt which may serve as the surfactant is calcium stearate. It will also be appreciated that calcium stearate is an example of an anionic surfactant. Calcium stearate (C36H70CaO4) is a mixture of calcium oxide with solid fatty acids such as stearic and palmitic acids and has a molar mass of 607.02 g / mol. A commercially available calcium stearate is Parteck® LUB CST (Merck).

[0049] One of the advantages of the recycling process in accordance with the present disclosure is that a used original article which includes a post-consumer recycled or post-industrial recycled polyolefin film can be reprocessed, that is, processed through a recycling process. After recycling, the recycled material from the previous virgin article can be used to make a subsequent recycled laminate, and in turn a recycled article, with properties and performances very close to the previous virgin article. One objective of the presently disclosed recycled polymer composition is to produce a recycled article that performs as well as, or better than, the original article, that is the properties of the recycled article performs 100 % the same as, or greater than, the properties of the original article. At a minimum, the properties of the recycled article are maintained at a sufficient level of performance to provide a recycled article that is useful in another application.

[0050] For example, a new monolayer film structure (recycled article) made with the recycled polymer composition can have properties that exhibit < 33 % decreased change in performance relative to a control article reprocessed the same way as the recycled polymer85729-WO-PCT / DOW 85729 WO composition but without the one or more adhering or coating auxiliaries and the surfactant. In some embodiments, the new monolayer film structure (recycled article) can have properties that exhibits a decreased change in performance at <30% in one embodiment, < 25% in one embodiment, < 20 % in another embodiment, and < 15 % in still another embodiment. In some embodiments, the new monolayer film structure can have properties that exhibits a decreased change in performance in the range of from 0 % to < 33 % in one embodiment, 0.01 % to < 33 % in another embodiment, and from 0.1 % to < 33 % in still another embodiment. In some embodiments, the new monolayer film structure can have properties that exhibits a decreased change in performance in the range of from 0 % to < 25 % in one embodiment, 0.01 % to < 25 % in another embodiment, and from 0.1 % to < 25 % in still another embodiment. In some embodiments, the new monolayer film structure can have properties that exhibits a decreased change in performance in the range of from 0 % to < 10 % in one embodiment, 0.01 % to < 10 % in another embodiment, and from 0.1 % to < 10 % in still another embodiment.

[0051] Further, it will be appreciated that in accordance with one or more embodiments, a new monolayer film structure (recycled article) made with the recycled polymer composition can have some properties that exhibit < 33 % decreased change in performance relative to a control article reprocessed the same way as the recycled polymer composition but without the one or more adhering or coating auxiliaries and the surfactant while one or more properties of the recycled article exhibit greater than a 33% decrease in performance. Such recycled articles still have utility as the maintained or improved properties may be sufficient for one or more applications. Further, in one or more embodiments, the recycled article may be better than a comparative article reprocessed the same way as the recycled polymer composition including the one or more adhering or coating auxiliaries. Such comparative article demonstrates the improvement in properties provided from inclusion of the surfactant.

[0052] In a general embodiment, the process for producing the recycled polymer composition and reprocessing into a recycled articles comprises the steps of: (A) providing a post- consumer recycled (PCR) or post-industrial recycled (PIR) polyolefin film which includes at least one adhering or coating auxiliary in accordance with the present disclosure; (B) fragmenting the polyolefin film from step (A) to produce a plurality of fragments of a predetermined size; (C) blending the plurality of fragments from step (B) with at least one surfactant to generate the recycled polymer composition; (D) pelletizing the recycled polymer composition from step (C) to85729-WO-PCT / DOW 85729 WO form a plurality of pellets of a predetermined size; and (E) processing the pellets from step (D) to form a recycled article. The surfactant is incorporated with the PCR or PIR polyolefin film allowing for recycling of the polyolefin film. For example, the surfactant may be used in a masterbatch of polyethylene resin that is blended with the reclaimed flexible packages, that is the PCR or PIR polyolefin film, to produce the recycled article. Accordingly, it has been unexpectantly discovered that incorporation of the surfactant as part of the compounding step (C) eliminates or minimizes formation of micron- to millimeter-sized gels as a result of the inclusion of adhering or coating auxiliaries present in the PCR or PIR polyolefin film.

[0053] In some embodiments, a third article can be produced from the recycled article made by the above general processes. For example, the third article can be selected from the group consisting of: pellets, monolayer or multilayer films, multilayer laminates, and packaging materials or products.

[0054] TEST METHODS

[0055] The test methods include the following:

[0056] Density (g / cm3)

[0057] To test density, samples are prepared and measured according to ASTM D792 at 190 ℃ and 2.16 kg for ethylene and 230 ℃ and 2.16 kg for propylene and reported in grams per cubic centimeter (g / cm3).

[0058] Melt Index (g / 10 Index (g / 10 min)

[0059] To test melt index, samples are prepared and measured according to ASTM D1238 and reported in grams per 10 minutes (g / 10 min).

[0060] Dart Impact (g)

[0061] To test the dart, samples are prepared and measured according to ASTM D1709 A and reported in grams (g).

[0062] Tear Strength (gram-force)85729-WO-PCT / DOW 85729 WO

[0063] To test the tear strength, samples are prepared and measured according to ASTM D1922 and reported in gram-force.

[0064] Tensile Strength (MPa)

[0065] To test the stress at break, samples are prepared and measured according to ASTM D638 and reported in MegaPascal (MPa).

[0066] Elongation (%)

[0067] To test the elongation at yield, samples are prepared and measured according to ASTM D882 and reported in percent elongation (%).

[0068] EXAMPLES

[0069] The following examples are presented to further illustrate the present invention in detail but are not to be construed as limiting the scope of the claims. Unless otherwise indicated, all parts and percentages are by weight.

[0070] Various materials used in the Inventive Examples (Inv. Ex.), the Comparative Examples (Comp. Ex.), and the Control Films which follow, are described in Table I. Table I - Raw Materials85729-WO-PCT / DOW 85729 WO

[0071] Various materials used as the surfactant in the Inventive Examples (Inv. Ex.) and the Comparative Examples (Comp. Ex.) which follow, are described in Table II. Table II - Surfactants

[0072] General Procedure for Production of Films

[0073] A sealant web film described in Table III, HDPE Film Structure was produced having seven layers with composition of each of the seven layers described in Tables III. The film was produced by using the following general process: The film was made on a seven layer blown film line (available from Hosokawa- Alpine). The line utilizes seven, 50 millimeter (mm) diameter, 30 L / D extruders that feed a 250 mm diameter spiral mandrel die with a 2 mm die gap. The output rate was 148 kilograms per hour (kg / hr) and the melt temperature ranged from 185 ℃ to 245 ℃. A 2.5 blow up ratio was used in blowing the film and the film was cooled with a single lip air ring and internal bubble cooling. The line speed was -17 meters per minute (m / min) and the film was corona treated to an average surface energy of 43 dynes / centimeter.85729-WO-PCT / DOW 85729 WO Table III - HDPE Film Structure

[0074] A first set of two of the HDPE films are laminated together with adhesive formed from MOR-Free™ L75-164 and MOR-Free™ C411 (MOR-Free™ 75-164 / C411) and a second set of two of the HDPE films are laminated together with adhesive formed from ADCOTE™ 577 and Dow™ CR87-124 (ADCOTE™ 577 / 87-124) using the process “General Procedure for Film Lamination” described herein below. Both the MOR-Free™ 75-164 / C411 and the ADCOTE™ 577 / 87-124 are adhesive formulations commonly utilized for production of films in consumer good.

[0075] Each of the resulting composite film laminates are reprocessed by shredding the films, pelletizing the films, extruding / compounding the pellets, and forming a second film from the compounded pellets originating from each of the first composite film laminates using the procedures described herein below.85729-WO-PCT / DOW 85729 WO

[0076] Subsequently, the second films are tested using the testing procedures described herein below with the results of the testing described in Tables VI and VII.

[0077] General Procedure for Film Lamination

[0078] Lamination is accomplished by using a Super - Combi 3000 series commercial laminator (available from Nordmeccanica). The laminator has a maximum film width of 1,320 mm and a minimum film width of 600 mm. Additionally, the laminator contains 2 modular coating decks: (1) a waterborne deck for waterborne lamination and (2) a Gravure deck for water- based and solvent-based adhesives / coatings. The laminator also contains 2 zone forced air dryers and a 7.5 kilowatt (KW) corona treater (available from Enercon Industries Corporation) for both a primary film and a secondary film. The maximum line speed of the laminator is 400 meters per minute (m / min) (or 1,312 feet per minute). All unwinds use a 76 mm or a 152 mm core and rewinds use only a 152-mm core. The laminator is capable of running most packing films such as polyester, oriented polypropylene, polyethylene, nylon, paper, foil (secondary only) and others. The HDPE films and the adhesives were run on the laminator with a target adhesive application of 1.6 grams per square meter (gsm) for the MOR-Free™ 75-164 / C411 samples and 2.9 gsm for the ADCOTE™ 577 / 87-124 samples utilizing the Gravure deck of the laminator. Upon completion of the lamination, the rolls of film were allowed to fully cure at room temperature for 7 days.

[0079] General Procedure for Film Shredding / Pelletizing

[0080] Shredding and pelletizing are accomplished using an INTAREMA® 605 K pelletizer unit (available from EREMA North America, Inc., Ipswich, Massachusetts). The barrel zone of the pelletizer is run at 171 °C; and the pelletizer zone is run at 176 °C.

[0081] Fabrication Line

[0082] Monolayer blown films were produced via a Collin LabLine E30P, avaiable from COLLIN Lab & Pilot Solutions GmbH, Maitenbeth, Germany. The line was comprised of three 25:1 L / D single screw extruders, equipped with grooved feed zones. The screw diameters were 25 mm for the inner layer, 30 mm for the core and 25 mm for the outer layer. The annular die was 60 mm in diameter and used a dual lip air ring cooling system. The film fabrication conditions were as follows: film thickness maintained at 50 μm (2.0 mil); blow up ratio (BUR) 2.5; die lip85729-WO-PCT / DOW 85729 WO gap was set at 2 mm; blow up ratio (BUR) was 2.5 and draw down ratio (DDR) was 31.5, Frost line height (FLH) was 165 mm (6.5 inches); The output rate of approximately was 8.80 kilograms per hour. Melt temperature and die temperature were set at 215° C. The standard conditions and possible ranges of conditions are summarized in Table V. Table V - Blown Film Fabrication Conditions

[0083] Testing

[0084] The Inventive Examples were prepared by fabricating recycled film with pellets generated from the laminated film and pellets generated from the HDPE film compounded at a 1:1 weight ratio along with 0.5 wt% of at least one surfactant. Inventive Examples 1 through 8 were generated using the laminated film with MOR-Free™ 75-164 / C411 along with one of the surfactants. Specifically, Inventive Example 1 includes 0.5 wt% of Span 85, Inventive Example 2 includes 0.5 wt% of Span 80, Inventive Example 3 includes 0.5 wt% of Tergitol™ NP-9, Inventive Example 4 includes 0.5 wt% of Parteck calcium stearate, Inventive Example 5 includes 0.5 wt% of Triton™ X-100, Inventive Example 6 includes 0.5 wt% of Everstab FS042, Inventive Example 7 includes 0.5 wt% of Hexadecyltrimethylammonium bromide, and Inventive Example 8 includes 0.5 wt% of Trihexyltetradecylphosphonium chloride. Similarly, Inventive Examples 9 through 16 were generated using the laminated film with ADCOTE™ 577 / 87-124 along with one of the surfactants. Specifically, Inventive Example 9 includes 0.5 wt% of Span 85, Inventive Example 10 includes 0.5 wt% of Span 80, Inventive Example 11 includes 0.5 wt% of Tergitol™ NP-9, Inventive Example 12 includes 0.5 wt% of Parteck calcium stearate, Inventive Example 13 includes 0.5 wt% of Triton™ X-100, Inventive Example 14 includes 0.5 wt% of Everstab FS042, Inventive Example 15 includes 0.5 wt% of Hexadecyltrimethylammonium bromide, and Inventive85729-WO-PCT / DOW 85729 WO Example 16 includes 0.5 wt% of Trihexyltetradecylphosphonium chloride. Table VI provides the make-up of each of Inventive Examples 1 through 16. Table VI – Formulation of Inventive Examples

[0085] Comparative Examples were prepared by fabricating recycled film with pellets generated from the laminated film and pellets generated from the HDPE film compounded at a 1:1 weight ratio. Comparative Example A was generated using the laminated film with MOR- Free™ 75-164 / C411 as the adhesive and Comparative Example B was generated using the laminated film with ADCOTE™ 577 / 87-124 as the adhesive. Comparative Example A corresponds to Inventive Examples 1-8 without the surfactant and Comparative Example B corresponds to Inventive Examples 9-16 without the surfactant.

[0086] Control Film consisting of the HPDE film and containing no laminating adhesive or surfactant was also prepared. The Control Film is the sample for which all laminated films are compared to.85729-WO-PCT / DOW 85729 WO

[0087] The films prepared in the Examples were tested for the following physical properties: Dart, Tear Strength, Elongation at Yield, and Tensile Strength. The tests were conducted as described in the following ASTM test methods: ASTM D1709 A was used to measure Drop Dart; ASTM D1922 was used to measure Tear Strength; ASTM D882 was used to measure Tensile Strength; and ASTM D822 was used to measure Elongation at Yield. The results for each of the Inventive Examples 1 through 8 and Comparative Example A are provided in Table VII (MOR-Free™ 75-164 / C411) and the results for each of the Inventive Examples 9 through 16 and Comparative Example B are provided in Table VIII (ADCOTE™ 577 / 87-124). Table VII - MOR-Free™ 75-164 / C411 Laminated Film Physical PropertiesTable VIII - ADCOTE™ 577 / 87-124 Laminated Film Physical Properties85729-WO-PCT / DOW 85729 WO

[0088] Tables IX and X provide the comparative results of testing films of the present disclosure (Inv. Ex.1-16) and the Comparative Examples (Comp. Ex. A and B). The comparison was calculated as the difference between the parameter value for the comparative or inventive example film and the control film divided by the parameter value for the control film. This metric shows the relative increase or decrease in the parameter value. A decrease of at most 33% is used as the criterion for recyclability. Table IX - MOR-Free™ 75-164 / C411 Laminated Film Comparative Performance85729-WO-PCT / DOW 85729 WO Table X - ADCOTE™ 577 / 87-124 Laminated Film Comparative Performance

[0089] Results

[0090] The results described in Tables IX and X show that inclusion of at least one surfactant in accordance with the present disclosure allow the recycled polymer film to pass the “< 33 % decreased change in performance” test in many instances in all categories as set forth in Tables VIII and IX. For example, the Dart performance is well within the performance boundaries with no inventive examples utilizing Span 85 or Span 80 having a 33 % decreased change in performance relative to the performance of the control film. It has been demonstrated that inclusion of a variety of surfactant types in accordance with the present disclosure pass the recyclability test. Specifically, Inventive Examples 1-6 and 9-10 pass the recyclability test where all measured parameters exhibited less than a 33% decreases relative to the control film.

[0091] It is further noted, Inventive Examples 7-8 and 11-16 may still be encompassed by the scope of the prepared claims as they demonstrate a marked improvement relative to85729-WO-PCT / DOW 85729 WO Comparative Examples. For example, Inventive Example 11 representing ADCOTE™ 577 / 87- 124 laminate with 0.5% Tergitol™ NP-9 exhibits a 44.7% reduction in Dart compared to the Control Film thus failing the strict recyclability test, but demonstrates an improvement or very minimal reduction in performance for the remaining parameters. This demonstrates that such film may provide beneficial use and allow recycling in applications where maximal Dart is not required. Further, Inventive Example 11 demonstrates a marked improvement broadly across the measured parameters relative to Comparative Example B where no surfactant was utilized.

[0092] It will be apparent that modifications and variations are possible without departing from the scope of the disclosure defined in the appended claims. More specifically, although some aspects of the present disclosure are identified herein as preferred or particularly advantageous, it is contemplated that the present disclosure is not necessarily limited to these aspects.

Claims

85729-WO-PCT / DOW 85729 WO CLAIMS 1. A recycled polymer composition comprising: (a) a post-consumer recycled (PCR) or post-industrial recycled (PIR) polyolefin film, the polyolefin film comprising: (i) at least one polyolefin polymer, and (ii) one or more adhering or coating auxiliaries; and (b) at least one surfactant, the surfactant being non-ionic, zwitterionic, cationic, anionic, or a metal salt, wherein: the recycled polymer composition comprises 0.1 to 1.5 wt.% of the surfactant.

2. The recycled polymer composition of claim 1, wherein the adhering or coating auxiliaries are selected from coatings and adhesives comprising one or more inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, or polyurethanes.

3. The recycled polymer composition of claim 1, wherein the one or more adhering or coating auxiliaries comprises a polyurethane based adhesive composition.

4. The recycled polymer composition of claim 1, wherein the surfactant is non-ionic.

5. The recycled polymer composition of claim 4, wherein the surfactant is a sorbitan ester.

6. The recycled polymer composition of any one of claims 1 to 5, wherein the recycled polymer composition comprises 0.4 to 0.6 wt.% of the surfactant.

7. The recycled polymer composition of any of claims 1 to 6, wherein the one or more adhering or coating auxiliaries form a coating layer on a surface of the polyolefin film, the coating layer comprising one or more inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, or polyurethanes.

8. The recycled polymer composition of any of claims 1 to 6, wherein the polyolefin film is a laminate, the laminate comprising: (a) at least one first polymer film layer, the first polymer film layer comprising a first85729-WO-PCT / DOW 85729 WO polyolefin polymer; (b) at least one second polymer film layer, the second polymer film layer comprising a second polyolefin polymer; and (c) the one or more adhering or coating auxiliaries, wherein the adhering or coating auxiliaries comprise an adhesive comprising one or more inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, or polyurethanes; wherein: the adhesive is disposed on the surface of at least one of the layers of the first film layer and the second film layer for binding the first film layer and the second film layer together.

9. The recycled polymer composition of claim 8, wherein the one or more adhering or coating auxiliaries form a coating layer on a surface of the laminate, the coating layer comprising one inorganic fillers, bio-derived tree resins and waxes, polypropylene, poly(vinyl acetate)-co-polyethylenes, polyesters, acrylics, or polyurethanes.

10. The recycled polymer composition of claim 8 or 9, wherein the first polyolefin polymer and the second polyolefin polymer comprise different compositions.

11. The recycled polymer composition of any of claims 8 to 10, wherein the first polymer film layer and the second polymer film layer comprise polyethylene PCR or PIR material.

12. The recycled polymer composition of any of claims 8 to 11, wherein the first polymer film layer and the second polymer film layer comprise high density polyethylene (HDPE) PCR or PIR material.

13. The recycled polymer composition of any of claims 8 to 12, wherein at least one of the first polymer film layer and the second polymer film layer comprises a multilayer film.

14. The recycled polymer composition of claim 13, wherein the first polymer film layer and the second polymer film layer comprise multilayer films.

15. The recycled polymer composition of any of claims 1 to 14, wherein the recycled polymer composition comprises a recyclability property such that a single layer blown film with a film thickness of 2 mil (50 μm) generated with the recycled polymer composition85729-WO-PCT / DOW 85729 WO exhibits less than a 33 percent decrease in performance compared to a control article reprocessed the same way as the recycled polymer composition but without the one or more adhering or coating auxiliaries and the surfactant.

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