Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F2410/00—Features related to the catalyst preparation, the catalyst use or to the deactivation of the catalyst
  • C08F2410/04—Dual catalyst, i.e. use of two different catalysts, where none of the catalysts is a metallocene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2203/00—Applications
  • C08L2203/16—Applications used for films
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
  • C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2207/00—Properties characterising the ingredient of the composition
  • C08L2207/06—Properties of polyethylene
  • C08L2207/062—HDPE
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2314/00—Polymer mixtures characterised by way of preparation
  • C08L2314/06—Metallocene or single site catalysts

Definitions

• This disclosure relates to polyethylene compositions, to films having a matte surface comprising polyethylene compositions, and to articles, such as labels and packages, comprising films having a matter surface.
• Flexible packaging film structures are often formed of multiple types of polymeric materials including, for example, polyethylene, polypropylene, ethylene vinyl alcohol, polyethylene terephthalate, polyamide and others. Such materials are typically combined to achieve a balance of properties that are beyond the reach of a single material type. However, due to the dissimilarity of these materials, the final package is typically not easy to recycle and a blend of materials can also create issues with process control. Thus, there is also a movement towards single component structures (e.g., all polyethylene structures) to improve the recyclability profile and to reduce process control issues.
• single component structures e.g., all polyethylene structures
• a matte surface can be defined in terms of optical properties with lower gloss and higher haze values as discussed herein.
• a common approach to obtaining a matte surface is to use a blend of polymers or inorganic fillers. For example, some methods use matte oriented polyethylene terephthalate and polypropylene to deliver a matte surface whereas other methods employ matte coatings. In addition to incorporating non-polyethylene polymers, these methods introduce additional process(es) to provide matte finish.
• Coextrusion of a polyethylene based matte layer is a more streamlined process, but coextrusion still typically relies on blending non-polyethylene components like polypropylene, cyclic olefinic copolymers, and micron sized inorganic particles in a layer to achieve matte finish. Furthermore, even when polyethylene resin designs are used, certain polyethylene resins are prone to dusting (i.e., powder formation), which, for example, can lead to contamination of film fabrication equipment.
• the present invention provides polyethylene compositions that can be extruded to form films that have a matter surface.
• a polyethylene composition in a first aspect, comprises from 30 to 70 wt.% of a first polyethylene component having a molecular weight distribution (Mw/Mn) of 1.50 to 2.50; from 30 to 70 wt.% of a second polyethylene component having a molecular weight distribution (Mw/Mn) of 1.50 to 2.50; wherein the wt.% of the first polyethylene component and second polyethylene component is based on the total weight of the polyethylene composition, wherein the first polyethylene component has a higher weight average molecular weight than the second polyethylene component, wherein the polyethylene composition has a density of 0.950 to 0.960 g/cm 3 , a melt index (I2) of 0.5 to 6.0 g/10 min, a molecular weight distribution (Mw/Mn) of 2.0 to 6.0, and a Mz of 100,000 to 500,000 g/mol.
• Mw/Mn molecular weight distribution
• Mw/Mn molecular weight distribution
• a film is disclosed.
• the film according to embodiments disclosed herein comprises the polyethylene composition of the first aspect of the invention.
• a label or package comprising the film is also disclosed.
• the present invention also provides articles, such as labels and packages, formed from any of the inventive polyethylene composition or films disclosed herein.
• composition 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.
• 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.
• interpolymer 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.
• 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.
• ethylene/a-olefin interpolymer refers to an interpolymer that comprises, in polymerized form, a majority amount (>50 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.
• ethylene/a-olefin copolymer 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.
• a-olefin refers to an alkene having a double bond at the primary or alpha (a) position.
• Polyethylene 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 polyethylene materials are generally known in the art; however, the following descriptions may be helpful in understanding the differences between some of these different polyethylene resins.
• LDPE Low Density Polyethylene
• LLDPE Linear Low Density Polyethylene
• ULDPE Ultra Low Density Polyethylene
• VLDPE Very Low Den
• 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 homo-polymerized or copolymerized in autoclave or tubular reactors at pressures above 14,500 psi (100 MPa) with the use of free-radical initiators, such as peroxides (see for example US 4,599,392, which is hereby incorporated by reference).
• LDPE resins typically have a density in the range of 0.916 to 0.935 g/cm 3 .
• LLDPE includes both resin 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 5,272,236, U.S. Patent 5,278,272, U.S.
• Patent 5,582,923 and US Patent 5,733,155 the homogeneously branched linear ethylene polymer compositions such as those 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 US 3,914,342 or US 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.
• MDPE refers to polyethylenes having densities from 0.926 to 0.940 g/cm 3 .
• MDPE is typically made using chromium or Ziegler-Natta catalysts or using singlesite catalysts including, but not limited to, bis-metallocene catalysts, constrained geometry catalysts, and molecular catalysts, and typically have a molecular weight distribution (“MWD”) greater than 2.5.
• MWD molecular weight distribution
• HDPE refers to polyethylenes having densities greater than about 0.940 g/cm 3 and up to about 0.970 g/cm 3 , 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.
• ULDPE refers to polyethylenes having densities of 0.880 to 0.912 g/cm 3 , 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 Ce-Cs a-olefin comonomer.
• Polyethylene plastomers/elastomers have a density from 0.870 g/cm 3 , or 0.880 g/ cm 3 , or 0.890 g/ cm 3 to 0.900 g/ cm 3 , or 0.902 g/ cm 3 , or 0.904 g/ cm 3 , or 0.909 g/ cm 3 , or 0.910 g/ cm 3 , or 0.917 g/ cm 3 .
• Nonlimiting examples of polyethylene plastomers/ elastomers include AFFINITYTM plastomers and elastomers (available from The Dow Chemical Company), EXACT Plastomers (available from ExxonMobil Chemical), Tafrner (available from Mitsui), NexleneTM (available from SK Chemicals Co.), and Lucene (available LG Chem Ltd.).
• Blends 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.
• adhering contact and like terms mean that one facial surface of one layer and one facial surface of another layer are in touching and binding contact to one another such that one layer cannot be removed from the other layer without damage to the interlayer surfaces (i.e., the in-contact facial surfaces) of both layers.
• compositions claimed through use of the term “comprising” may include any additional additive, adjuvant, or compound, whether polymeric or otherwise, unless stated to the contrary.
• 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.
• the present invention relates to a polyethylene composition.
• the polyethylene composition comprises a first polyethylene component and a second polyethylene component.
• the first polyethylene component and second polyethylene component can be a dry blend of polymers, melt blend of polymers, or in reactor blend of polymers.
• the polyethylene composition is formed in a single reactor or in a dual reactor such as a dual loop reactor.
• the first polyethylene component and the second polyethylene component are not the same or identical.
• the first polyethylene component has a higher weight average molecular weight (Mw) than the second polyethylene component. The Mw of each component can be measured in accordance with the test methods below.
• the polyethylene composition has a density of 0.950 to 0.960 g/cm 3 .
• the polyethylene composition has a density lower limit of 0.950, 0.951, 0.952, 0.953, 0.954, 0.955, 0.956, 0.957, 0.958, or 0.959 g/cm 3 and an upper limit of 0.951, 0.952, 0.953, 0.954, 0.955, 0.956, 0.957, 0.958, 0.959, or 0.960 g/cm 3 .
• the polyethylene composition has a melt index (I2) of 0.5 to 6.0 g/10 min.
• the polyethylene composition has a melt index (I2) of a lower limit of 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, or 5.5 g/10 min and an upper limit of 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5 or 6.0 g/10 min.
• the polyethylene composition has a molecular weight distribution (Mw/Mn) of 2.0 to 6.0.
• the polyethylene composition has a molecular weight distribution (Mw/Mn) of a lower limit of 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, or 5.5 and an upper limit of 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, or 6.0.
• the polyethylene composition has a Mz of 100,000 to 500,000 g/mol.
• the polyethylene composition has a Mz of lower limit of 100,000, 150,000, 200,000, 250,000, 300,000, 350,000, 400,000 or 450,000 g/mol and an upper limit of 150,000, 200,000, 250,000, 300,000, 350,000, 400,000, 450,000 or 500,000 g/mol.
• the characteristics of the polyethylene composition can be measured in accordance with the test methods below.
• the polyethylene composition comprises from 30 to 70 wt.% of a first polyethylene component, based on the total weight of the polyethylene composition.
• the polyethylene composition comprises from 30 to 70 wt.%, or 33 to 65 wt.% or 33 to 66 wt.%, or 30 to 40 wt.%, or 55 to 65 wt.% of the first component, based on the total weight of the polyethylene composition.
• the first polyethylene component has a molecular weight distribution (Mw/Mn) of 1.50 to 2.50.
• the first polyethylene component has a molecular weight distribution of lower limit of 1.60, 1.70, 1.80, 1.90, 2.00, 2.10, 2.20, 2.30, or 2.40 to an upper limit of 2.50, 2.40, 2.30, 2.20, 2.10, 2.00, 1.90, 1.80, 1.70, or 1.60.
• the molecular weight distribution (Mw/Mn) of the first component can be measured in accordance with the test methods described below.
• the first polyethylene component has a Mw greater than the second polyethylene component.
• the first polyethylene component has a Mw of greater than 80,000 g/mol, or greater than 100,000 g/mol, or greater than 140,000 g/mol, or greater than 150,000 g/mol, or greater than 180,000 g/mol, or greater than 200,000 g/mol, or greater than 210,000 g/mol, or greater than 230,000 g/mol, or greater than 250,000 g/mol.
• the first polyethylene component has a density lower than the density of the second polyethylene component.
• the first polyethylene component has a density of less than 0.958 g/cm 3 , or less than 0.956 g/cm 3 , or less than 0.954 g/cm 3 , or less than 0.952 g/cm 3 , or less than 0.950 g/cm 3 , or less than 0.948 g/cm 3 , or from 0.940 to 958 g/cm 3 , or from 0.942 to 0.955 g/cm 3 , or from 0.944 to 0.953 g/cm 3 .
• the density of each component can be measured in accordance with the test methods below.
• the polyethylene composition comprises from 30 to 70 wt.% of a second polyethylene component, based on the total weight of the polyethylene composition.
• the polyethylene composition comprises from 30 to 70 wt.%, or 33 to 65 wt.% or 33 to 66 wt.%, or 30 to 40 wt.%, or 55 to 65 wt.% of the second component, based on the total weight of the polyethylene composition.
• the second polyethylene component has a molecular weight distribution (Mw/Mn) of 1.50 to 2.50.
• the second polyethylene component has a molecular weight distribution of lower limit of 1.60, 1.70, 1.80, 1.90, 2.00, 2.10, 2.20, 2.30, or 2.40 to an upper limit of 2.50, 2.40, 2.30, 2.20, 2.10, 2.00, 1.90, 1.80, 1.70, or 1.60.
• the molecular weight distribution (Mw/Mn) of the second component can be measured in accordance with the test methods described below.
• the second polyethylene component has a Mw lower than the first polyethylene component.
• the second polyethylene component has a Mw of less than 80,000 g/mol, or less than 70,000 g/mol, or less than 60,000 g/mol, or less than 50,000 g/mol, or less than 40,000 g/mol, or less than 30,000 g/mol.
• the second polyethylene component has a density higher than the density of the first polyethylene component.
• the second polyethylene component has a density of greater than 0.958 g/cm 3 , or greater than 0.960 g/cm 3 , or greater than 0.962 g/cm 3 , or greater than 0.964 g/cm 3 , or greater than 0.966 g/cm 3 , or greater than 0.968 g/cm 3 , or from 0.958 to 0.974 g/cm 3 , or from 0.959 to 0.972 g/cm 3 , or from 0.960 to 0.971 g/cm 3 .
• the density of each component can be measured in accordance with the test methods below.
• the present invention also relates to films comprising the polyethylene composition disclosed herein and having at least one matte surface and to articles, labels, and packages formed from such films.
• the matte surface can provide a desirable appearance.
• a film comprises the polyethylene composition.
• the film comprises an outer layer, wherein the outer layer comprises the polyethylene composition according to embodiments disclosed herein.
• the film can be a blown film, cast film, oriented film, or cast-stretch film. In one embodiment, the film is a blown film.
• the outer layer of the film comprises greater than 50 wt.%, greater than 60 wt.%, greater than 70 wt.%, greater than 80 wt.%, greater than 90 wt.%, greater than 95 wt.%, greater than 98 wt. %, greater than 99 wt.%, or greater than 99.5 wt.% of the polyethylene composition disclosed herein.
• the film has a gloss of less than 10%, or less than 9% or less than 8%, or less than 7%.
• the gloss of the film can be measured in accordance with the test methods described below.
• the film has a total haze greater than 60% or greater than 70% or greater than 80%.
• the total haze of the film can be measured in accordance with the test methods described below.
• the film has an internal haze of greater than 8%, or greater than 10%, or greater than 12% or greater than 14% or greater than 16%.
• the internal haze of the film can be measured in accordance with the test methods described below.
• the film comprises greater than 95 wt.%, or greater than 97 wt.%, or greater than 99 wt.%, or greater than 99.9 wt.% polyethylene, based on the total polymer content of the film. In some embodiments, the film is void of polymers other than polyethylene.
• the present invention also provides articles, such as labels and packages, formed from any of the inventive films disclosed herein.
• the outer layer in a film can provide a matte surface.
• matte surface generally refers to a surface with a dull appearance, as opposed to a glossy appearance.
• a matte surface as discussed herein has one or both of (1) a gloss of less than 10%, and (2) a haze of greater than 60%.
• a film comprises an outer layer comprising the polyethylene composition according to embodiments disclosed herein and an inner layer in adhering contact with the outer layer.
• the inner layer can comprise a LDPE, LLDPE, MDPE, HDPE, or a combination thereof. Suitable LLDPEs for use in the inner layer include DOWLEX grades commercially available from The Dow Chemical Company.
• the inner layer comprises a low density polyethylene (e.g., an LDPE or LLDPE) having a density of 0.919 to 0.940 g/cm 3 .
• the density of the low density polyethylene can be from a lower limit of 0.919, 0.920, 0.922, 0.925, 0.927, 0.929, or 0.930 g/ cm 3 to an upper limit of 0.925, 0.930, 0.935, or 0.940 g/cm 3 .
• the low density polyethylene has a density of 0.930 to 0.940 g/cm 3 .
• the low density polyethylene has a melt index (E) 0.3 to 5 g/10 minutes. All individual values and subranges from 0.3 to 5 g/10 minutes are included herein and disclosed herein.
• the low density polyethylene can have an E from a lower limit of 0.3, 0.5, 0.7, 0.9, 1.0, 1.2, 1.5, 1.8, 2.0, 2.3, 2.5, 2.7, 3.0, 3.3, or 3.5 g/10 minutes to an upper limit of 2.0, 2.5, 2.8, 3.0, 3.2, 3.5, 3.7, 4.0, 4.2, 4.5, 4.8, or 5 g/10 minutes.
• the low density polyethylene can have an I2 of 2.5 to 4.0 g/10 minutes.
• low density polyethylenes examples include DOWTM low density polyethylenes (LDPE) commercially available from The Dow Chemical Company, such as DOWTM LDPE 525E, DOWTM LDPE 410E, DOWTM LDPE 421E, DOWTM LDPE 545E, DOWTM LDPE 555E, and DOWTM LDPE 515E, and DOWLEXTM LLDPE resins commercially available from The Dow Chemical Company.
• DOWTM low density polyethylenes such as DOWTM LDPE 525E, DOWTM LDPE 410E, DOWTM LDPE 421E, DOWTM LDPE 545E, DOWTM LDPE 555E, and DOWTM LDPE 515E
• DOWLEXTM LLDPE resins commercially available from The Dow Chemical Company.
• Films of the present invention can comprise a variety of other layers in addition to an outer layer and an inner layer.
• the number of layers in the film can depend on a number of factors including, for example, the desired properties of the film, the end use application, the desired thickness of the film, and others.
• the other layers when the film is to be used in package may be different from the other layers used when the film is to be used as a label. Examples of different layers that can be used in various embodiments are discussed further herein.
• Films of the present invention comprise up to 13 layers in some embodiments. In various embodiments, the film comprises 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, or 13 layers.
• a film of the present invention comprises a second outer layer which is a sealant layer.
• the sealant layer can be used to form an article or package by using the sealant layer to adhere the film to another film, to a laminate, or to itself.
• the sealant layer can comprise any resins known to those having ordinary skill in the art to be useful as a sealant layer.
• polymers that can be used to form a sealant layer in some embodiments of the present invention include, without limitation, LDPE (e.g., DOWTM LDPE and AGILITYTM LDPE commercially available from The Dow Chemical Company), LLDPE (e.g., DOWLEXTM LLDPE resins commercially available from The Dow Chemical Company), polyolefin plastomers or elastomers (e.g., AFFINITYTM plastomers and elastomers commercially available from The Dow Chemical Company), ethylene vinyl acetate copolymers (e.g., ELVAXTM ethylene vinyl acetate copolymers commercially available from The Dow Chemical Company) and ionomers of ethylene acid copolymers (e.g., SURLYNTM ionomers commercially available from The Dow Chemical Company).
• LDPE e.g., DOWTM LDPE and AGILITYTM LDPE commercially available from The Dow Chemical Company
• LLDPE e.g.,
• the film comprises a second outer layer that provides a second matte surface and comprises the polyethylene composition according to embodiments disclosed herein.
• the film can comprise other layers such as barrier layers.
• barrier layers can comprise, for example, polymers used in barrier layers as known to those of skill in the art.
• an inner layer of the film comprises ethylene vinyl alcohol copolymer.
• the film comprises 30 weight percent or less ethylene vinyl alcohol copolymer based on the total weight of the film. In some embodiments, the film comprises 20 weight percent or less ethylene vinyl alcohol copolymer based on the total weight of the film.
• the film comprises 10 weight percent or less ethylene vinyl alcohol copolymer based on the total weight of the film. In some embodiments, the film comprises less than 5% by weight ethylene vinyl alcohol copolymer and polyamide based on the total weight of the film.
• one or more tie layers may be included in the film to adhere the barrier layer(s) other layers as known to those of skill in the art based on the teachings herein.
• tie layer compositions can be used to form a tie layer as known to those of skill in the art based on the teachings herein.
• barrier properties may not be as important for the film.
• the film may comprise less than 0.5 weight percent ethylene vinyl alcohol copolymer based on the total weight of the film. In some embodiments, the film comprises less than 0.1 weight percent ethylene vinyl alcohol copolymer based on the total weight of the film. In some embodiments, the film is free of ethylene vinyl alcohol copolymer and polyamide.
• a film of the present invention has a total thickness of at least 30 microns. In some embodiments, the film has a thickness of up to 90 microns. In some embodiments, the film has a thickness from 30 microns to 90 microns.
• Films of the present invention can exhibit one or more desirable properties. As discussed elsewhere, the films of the present invention have a matte surface. Films can be coextruded as blown films or cast films using techniques known to those of skill in the art based on the teachings herein. In particular, based on the compositions of the different film layers disclosed herein, blown film manufacturing lines and cast film manufacturing lines can be configured to coextrude films of the present invention in a single extrusion step using techniques known to those of skill in the art based on the teachings herein.
• Embodiments of the present invention also comprise labels formed from or incorporating films of the present invention.
• Such labels can be made from the inventive polyethylene compositions using techniques known to those having ordinary skill in the art based on the teachings herein.
• Embodiments of the present invention also comprise packages formed from or incorporating polyethylene compositions of the present invention.
• Such packages can be made from the inventive polyethylene compositions and films comprising such compositions using techniques known to those having ordinary skill in the art based on the teachings herein.
• packages can include flexible packages, pouches, stand-up pouches, and pre-made packages or pouches.
• films of the present invention can be used for food packages.
• food packages examples include meats, cheeses, cereal, nuts, juices, sauces, and others.
• Such packages can be formed using techniques known to those of skill in the art based on the teachings herein and based on the particular use for the package (e.g., type of food, amount of food, etc.).
• Melt index I2 (or 12) is measured in accordance to ASTM D-1238 (method B) at 190°C and at 2.16 kg. Their values are reported in g/10 min.
• Samples for density measurement are prepared according to ASTM D4703 Annex A. 1 Proc C. Measurements were made, according to ASTM D792, Method B, within one hour of sample pressing.
• Haze is measured according to ASTM D 1003. A Hazegard Plus (BYK-Gardner USA; Columbia, MD) was used for testing. For each test, 5 samples were examined, and an average was reported. For Internal Haze, a small amount of mineral oil is placed on both surfaces of the film and the oil spread evenly using a cotton swab. The sample is then placed as close as possible to the haze port and a reading taken.
• Gloss at an angle of 45° was measured according to ASTM D2457 on a BYK- Gardner (Columbia, MD) micro-gloss 45 degree gloss meter (Columbia, MD).
• ASTM D2457 on a BYK- Gardner (Columbia, MD) micro-gloss 45 degree gloss meter (Columbia, MD).
• the specimens are placed in a telescoping hoop to ensure there are no wrinkles/folds in the film. The specimen is placed on a black background and the gloss meter placed on the specimen and a reading taken. Five replicates are measured per sample.
• the chromatographic system consisted of a PolymerChar GPC-IR (Valencia, Spain) high temperature GPC chromatograph equipped with an internal IR5 infra-red detector (IR5) and 4-capillary viscometer (DV) coupled to a Precision Detectors (Now Agilent Technologies) 2-angle laser light scattering (LS) detector Model 2040. For all absolute Light scattering measurements, the 15 degree angle is used for measurement.
• the autosampler oven compartment was set at 160° Celsius and the column and detector compartment were set at 150° Celsius.
• the columns used were 4 Agilent “Mixed A” 30cm 20-micron linear mixed-bed columns.
• the chromatographic solvent used was 1,2,4 tri chlorobenzene and contained 200 ppm of butylated hydroxytoluene (BHT).
• BHT butylated hydroxytoluene
• the solvent source was nitrogen sparged.
• the injection volume used was 200 microliters and the flow rate was 1.0 milliliters/minute.
• Calibration of the GPC column set was performed with 21 narrow molecular weight distribution polystyrene standards with molecular weights ranging from 580 to 8,400,000 and were arranged in 6 “cocktail” mixtures with at least a decade of separation between individual molecular weights.
• the standards were purchased from Agilent Technologies.
• the polystyrene standards were prepared at 0.025 grams in 50 milliliters of solvent for molecular weights equal to or greater than 1,000,000, and 0.05 grams in 50 milliliters of solvent for molecular weights less than 1,000,000.
• the polystyrene standards were pre-dissolved at 80 °C with gentle agitation for 30 minutes then cooled and the room temperature solution is transferred cooled into the autosampler dissolution oven at 160°C for 30 minutes.
• Equation 1 The polystyrene standard peak molecular weights were converted to polyethylene molecular weights using Equation 1 (as described in Williams and Ward, J. Polym. Sci., Polym. Let., 6, 621 (1968)).: where M is the molecular weight, A has a value of 0.4028 and B is equal to 1.0.
• a fifth order polynomial was used to fit the respective polyethylene-equivalent calibration points.
• the total plate count of the GPC column set was performed with decane which was introduced into blank sample via a micropump controlled with the PolymerChar GPC-IR system.
• the plate count for the chromatographic system should be greater than 18,000 for the 4 Agilent “Mixed A” 30cm 20-micron linear mixed-bed columns.
• Samples were prepared in a semi-automatic manner with the PolymerChar “Instrument Control” Software, wherein the samples were weight-targeted at 2 mg/ml, and the solvent (contained 200ppm BHT) was added to a pre nitrogen-sparged septa-capped vial, via the PolymerChar high temperature autosampler. The samples were dissolved for 2 hours at 160° Celsius under “low speed” shaking.
• Mn(GPC), MW(GPC), and MZ(GPC) were based on GPC results using the internal IR5 detector (measurement channel) of the PolymerChar GPC-IR chromatograph according to Equations 2-4, using PolymerChar GPCOneTM software, the baseline-subtracted IR chromatogram at each equally-spaced data collection point (i), and the polyethylene equivalent molecular weight obtained from the narrow standard calibration curve for the point (i) from Equation 1.
• a flowrate marker (decane) was introduced into each sample via a micropump controlled with the PolymerChar GPC-IR system.
• This flowrate marker (FM) was used to linearly correct the pump flowrate (Flowrate(nominal)) for each sample by RV alignment of the respective decane peak within the sample (RV(FM Sample)) to that of the decane peak within the narrow standards calibration (RV(FM Calibrated)). Any changes in the time of the decane marker peak are then assumed to be related to a linear-shift in flowrate (Flowrate(effective)) for the entire run.
• the effective flowrate (with respect to the narrow standards calibration) is calculated as Equation 5. Processing of the flow marker peak was done via the PolymerChar GPCOneTM Software. Acceptable flowrate correction is such that the effective flowrate should be within +/-0.5% of the nominal flowrate.
• Flowrate(effective) Flowrate(nominal) * (RV(FM Calibrated) / RV(FM Sample))(EQ5)
• the weight fraction result of the measured GPC molecular weight distribution was interpolated along 601 log M points using a 2 nd -order polynomial.
• Microsoft ExcelTM 2010 Solver was used to minimize the sum of squares of residuals for the equally-spaces range of 601 LogM points between the interpolated chromatographically determined molecular weight distribution and the two broadened Flory distribution components (.siand 2), weighted with their respective component compositions, Ai and A2.
• the iteration starting values for the components are as follows:
• the bounds for components 1 and 2 are such that 5 is constrained such that 5 > 0.001, yielding an Mw/Mn of approximately 2.00 and 5 ⁇ 0.550, yielding a Mw/Mn of approximately 5.71.
• the composition, Ai is constrained between 0.000 and 1.000.
• the Mwi is constrained between 2,500 and 2,000,000.
• the composition, A2, is constrained between 0.000 and 1.000.
• the Mw2 is constrained between 2,500 and 2,000,000.
• the “GRG Nonlinear” engine was selected in Excel SolverTM and precision was set at 0.00001 and convergence was set at 0.0001. The solutions were obtained after convergence (in all cases shown, the solution converged within 60 iterations).
• All raw materials (monomer and comonomer) and the process solvent (a narrow boiling range high-purity isoparaffinic solvent, Isopar-E) are purified with molecular sieves before introduction into the reaction environment. Hydrogen is supplied pressurized as a high purity grade and is not further purified.
• the reactor monomer feed stream is pressurized via a mechanical compressor to above reaction pressure.
• the solvent and comonomer feed is pressurized via a pump to above reaction pressure.
• the individual catalyst components are manually batch diluted with purified solvent and pressured to above reaction pressure. All reaction feed flows are measured with mass flow meters and independently controlled with computer automated valve control systems.
• the continuous solution polymerization reactor consists of a liquid full, non-adiabatic, isothermal, circulating, loop reactor which mimics a continuously stirred tank reactor (CSTR) with heat removal. Independent control of all fresh solvent, monomer, comonomer, hydrogen, and catalyst component feeds is possible.
• the total fresh feed stream to the reactor (solvent, monomer, comonomer, and hydrogen) is temperature controlled to maintain a single solution phase by passing the feed stream through a heat exchanger.
• the total fresh feed to the polymerization reactor is injected into the reactor at two locations with approximately equal reactor volumes between each injection location. The fresh feed is controlled with each injector receiving half of the total fresh feed mass flow.
• the catalyst components are injected into the polymerization reactor through an injection stinger.
• the primary catalyst component feed is computer controlled to maintain the reactor monomer conversion at the specified targets.
• the cocatalyst component is fed based on calculated specified molar ratio to the primary catalyst component.
• the feed streams are mixed with the circulating polymerization reactor contents with static mixing elements.
• the contents of the reactor are continuously circulated through heat exchangers responsible for removing much of the heat of reaction and with the temperature of the coolant side responsible for maintaining an isothermal reaction environment at the specified temperature. Circulation around the reactor loop is provided by a pump.
• the reactor effluent enters a zone where it is deactivated with the addition of and reaction with a suitable reagent (water) and a neutralizer added (calcium stearate).
• a suitable reagent water
• a neutralizer calcium stearate
• other additives are added for polymer stabilization (typical antioxidants suitable for stabilization during extrusion and blown film fabrication like Octadecyl 3,5-Di- Tert-Butyl-4-Hydroxyhydrocinnamate, Tetrakis(Methylene(3,5-Di-Tert-Butyl-4-
• the reactor effluent enters a devolatization system where the polymer is removed from the non-polymer stream.
• the isolated polymer melt is pelletized and collected.
• the non-polymer stream passes through various pieces of equipment which separate most of the ethylene which is removed from the system.
• Most of the solvent and unreacted comonomer is recycled back to the reactor after passing through a purification system. A small amount of solvent and comonomer is purged from the process.
• the reactor stream feed data flows that correspond to the values in Table 1 used to produce the example are graphically described in Diagram A.
• the data are presented such that the complexity of the solvent recycle system is accounted for and the reaction system can be treated more simply as a once through flow diagram.
• All raw materials (monomer, comonomer, hydrogen) and the process solvent (a narrow boiling range high-purity isoparaffinic solvent, Isopar-E) are purified with molecular sieves before introduction into the reaction environment.
• the hydrogen feed is pressurized by a compressor to above reaction pressure.
• the reactor monomer feed stream is pressurized via a compressor to above reaction pressure.
• the solvent and comonomer feed is pressurized via a pump to above reaction pressure.
• the individual catalyst components are fed to the reactor using dedicated feed metering systems and pumps. All reaction feed flows are measured with mass flow meters and independently controlled with computer automated valve control systems.
• the first continuous solution polymerization reactor consists of a liquid full, non-adiabatic, isothermal, circulating, loop reactor which mimics a continuously stirred tank reactor (CSTR) with heat removal. Independent control of all fresh solvent, monomer, comonomer, hydrogen, and catalyst component feeds is possible.
• the total fresh feed stream to the first reactor (solvent, monomer, comonomer, and hydrogen) is temperature controlled to maintain a single solution phase by passing the feed stream through a heat exchanger.
• the total fresh feed to the first polymerization reactor is injected into the reactor at two locations with approximately equal reactor volumes between each inj ection location. The fresh feed is controlled with each inj ector receiving half of the total fresh feed mass flow.
• the catalyst components are injected into the polymerization reactor through dedicated injectors.
• the primary catalyst component feed is computer controlled to maintain the reactor monomer conversion at the specified target.
• the cocatalyst component are fed based on calculated specified molar ratios to the primary catalyst component.
• the feed streams are mixed with the circulating polymerization reactor contents with static mixing elements.
• the contents of the reactor are continuously circulated through heat exchangers responsible for removing much of the heat of reaction and with the temperature of the coolant side responsible for maintaining an isothermal reaction environment at the specified temperature. Circulation around the first reactor loop is provided by a pump.
• the effluent from the first polymerization reactor exits the first reactor and is added to the second reactor.
• the second continuous solution polymerization reactor consists of a liquid full, non-adiabatic, isothermal, circulating, loop reactor which mimics a continuously stirred tank reactor (CSTR) with heat removal. Independent control of all fresh solvent, monomer, comonomer, hydrogen, and catalyst component feeds is possible.
• the total fresh feed stream to the second reactor (solvent, monomer, comonomer, and hydrogen) is temperature controlled to maintain a single solution phase by passing the feed stream through a heat exchanger.
• the total fresh feed to the second polymerization reactor is injected into the reactor at two locations with approximately equal reactor volumes between each injection location.
• the fresh feed is controlled with each injector receiving half of the total fresh feed mass flow.
• the catalyst components are injected into the polymerization reactor through dedicated injectors.
• the primary catalyst component feed is computer controlled to maintain the reactor monomer conversion at the specified target.
• the cocatalyst component is fed based on a specified molar ratio to the primary catalyst component.
• the streams are mixed with the circulating polymerization reactor contents with static mixing elements.
• the contents of the second reactor are continuously circulated through heat exchangers responsible for removing much of the heat of reaction and with the temperature of the coolant side responsible for maintaining an isothermal reaction environment at the specified temperature. Circulation around the second reactor loop is provided by a pump.
• the final reactor effluent enters a zone where it is deactivated with the addition of and reaction with a suitable reagent (water) and a neutralizer added (calcium stearate).
• a suitable reagent water
• a neutralizer calcium stearate
• other additives are added for polymer stabilization (typical antioxidants suitable for stabilization during extrusion and blown film fabrication like Octadecyl 3,5-Di- Tert-Butyl-4-Hydroxyhydrocinnamate, Tetrakis(Methylene(3,5-Di-Tert-Butyl-4-
• the reactor effluent enters a devolatization system where the polymer is removed from the non-polymer stream.
• the isolated polymer melt is pelletized and collected.
• the non-polymer stream passes through various pieces of equipment which separate most of the ethylene which is removed from the system.
• Most of the solvent and unreacted comonomer is recycled back to the reactor after passing through a purification system. A small amount of solvent and comonomer is purged from the process.
• All raw materials (monomer and comonomer) and the process solvent (a narrow boiling range high-purity isoparaffinic solvent, Isopar-E) are purified with molecular sieves before introduction into the reaction environment. Hydrogen is supplied pressurized as a high purity grade and is not further purified.
• the reactor monomer feed stream is pressurized via a mechanical compressor to above reaction pressure.
• the solvent and comonomer feed is pressurized via a pump to above reaction pressure.
• the individual catalyst components are manually batch diluted with purified solvent and pressured to above reaction pressure. All reaction feed flows are measured with mass flow meters and independently controlled with computer automated valve control systems.
• the first continuous solution polymerization reactor consists of a liquid full, non-adiabatic, isothermal, circulating, loop reactor which mimics a continuously stirred tank reactor (CSTR) with heat removal. Independent control of all fresh solvent, monomer, comonomer (if used), hydrogen, and catalyst component feeds is possible.
• the total fresh feed stream to the first reactor (solvent, monomer, comonomer - if used, and hydrogen) is temperature controlled to maintain a single solution phase by passing the feed stream through a heat exchanger.
• the total fresh feed to the first polymerization reactor is injected into the reactor at three locations with approximately equal reactor volumes between each injection location.
• the fresh feed is controlled with each injector receiving one third of the total fresh feed mass flow.
• the catalyst components are injected into the polymerization reactor at two different locations with similar reactor volumes between each injection location.
• the primary catalyst component feed is computer controlled to maintain the reactor monomer conversion at the specified target.
• the cocatalyst components are fed based on calculated specified molar ratios to the primary catalyst component.
• the streams are mixed with the circulating polymerization reactor contents with static mixing elements.
• the contents of the reactor are continuously circulated through heat exchangers responsible for removing much of the heat of reaction and with the temperature of the coolant side responsible for maintaining an isothermal reaction environment at the specified temperature. Circulation around each reactor loop is provided by a pump.
• the second continuous solution polymerization reactor consists of a liquid full, non- adiabatic, isothermal, circulating, loop reactor which mimics a continuously stirred tank reactor (CSTR) with heat removal. Independent control of all fresh solvent, monomer, comonomer (if used), hydrogen, and catalyst component feeds is possible.
• the total fresh feed stream to the second reactor (solvent, monomer, comonomer - if used, and hydrogen) is temperature controlled to maintain a single solution phase by passing the feed stream through a heat exchanger.
• the total fresh feed to the polymerization reactor is injected into the reactor at two locations with approximately equal reactor volumes between each injection location. The fresh feed is controlled with each injector receiving half of the total fresh feed mass flow.
• the catalyst components are injected into the polymerization reactor through injection stingers.
• the primary catalyst component feed is computer controlled to maintain the reactor monomer conversion at the specified target.
• the boron containing cocatalyst component is fed based on calculated specified molar ratio to the primary catalyst component, and the Al containing cocatalyst component is fed to target a specified concentration in the reactor.
• the streams are mixed with the circulating polymerization reactor contents with static mixing elements.
• the contents of each reactor are continuously circulated through heat exchangers responsible for removing much of the heat of reaction and with the temperature of the coolant side responsible for maintaining an isothermal reaction environment at the specified temperature. Circulation around each reactor loop is provided by a pump.
• the effluent from the first polymerization reactor (containing solvent, monomer, comonomer, hydrogen, catalyst components, and polymer) exits the first reactor and is added to the second reactor.
• the final reactor effluent enters a zone where it is deactivated with the addition of and reaction with a suitable reagent (water).
• a suitable reagent water
• other additives are added for polymer stabilization (typical antioxidants suitable for stabilization during extrusion and blown film fabrication like Octadecyl 3,5-Di-Tert-Butyl-4-Hydroxyhydrocinnamate, Tetrakis(Methylene(3,5-Di-Tert-Butyl-4-Hydroxyhydrocinnamate))Methane, and Tris(2,4-Di- Tert-Butyl-Phenyl) Phosphite).
• the reactor effluent enters a devolatization system where the polymer is removed from the non-polymer stream.
• the isolated polymer melt is pelletized and collected.
• the non-polymer stream passes through various pieces of equipment which separate most of the ethylene which is removed from the system.
• Most of the solvent and unreacted comonomer is recycled back to the reactor after passing through a purification system. A small amount of solvent and comonomer is purged from the process.
• the reactor stream feed data flows that correspond to the values in Table 3 used to produced the example are graphically described in Diagram 3. The data are presented such that the complexity of the solvent recycle system is accounted for and the reaction system can be treated more simply as a once through flow diagram.
• CE2 DOWTM DGDA-6098 NT 7
• CE3 UNIV ALTM DMDA-6400 NT 7
• Films are formed from the polyethylene compositions (e.g., IE1 polyethylene composition is formed into film IE1 and so on per Tables 4 and 5). The gloss, total haze, and internal haze are measured. Each film is comprised of 99% of each of the inventive and comparative examples and 1% processing aid master batch commercially available from Ingenia polymers.
• the films are extruded on a single extruder mono-layer blown film line.
• the nominal film thickness is 25 microns.
• the line was comprised of a 3.5 inch, 30 L/D DSBII screw, 8 inch monolayer die, 70 mil die gap and internal bubble cooling (IBC).
• the melt temperature is 200° C-220° C.
• the blow-up ratio is 2.5: 1.
• the output rate is 250 Ibs/hr. Table 5 - Gloss and Haze
• IE1-3 have significantly lower gloss.
• the compositions have a similar density, Mw/Mn and Mz, but IE1 has significantly lower gloss.

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